9863 Commits

Author	SHA1	Message	Date
Linus Torvalds	1d35aae78f	Kbuild updates for v6.9 ... - Generate a list of built DTB files (arch/*/boot/dts/dtbs-list) - Use more threads when building Debian packages in parallel - Fix warnings shown during the RPM kernel package uninstallation - Change OBJECT_FILES_NON_STANDARD_*.o etc. to take a relative path to Makefile - Support GCC's -fmin-function-alignment flag - Fix a null pointer dereference bug in modpost - Add the DTB support to the RPM package - Various fixes and cleanups in Kconfig -----BEGIN PGP SIGNATURE----- iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAmX8HGIVHG1hc2FoaXJv eUBrZXJuZWwub3JnAAoJED2LAQed4NsGYfIQAIl/zEFoNVSHGR4TIvO7SIwkT4MM VAm0W6XRFaXfIGw8HL/MXe+U9jAyeQ9yL9uUVv8PqFTO+LzBbW1X1X97tlmrlQsC 7mdxbA1KJXwkwt4wH/8/EZQMwHr327vtVH4AilSm+gAaWMXaSKAye3ulKQQ2gevz vP6aOcfbHIWOPdxA53cLdSl9LOGrYNczKySHXKV9O39T81F+ko7wPpdkiMWw5LWG ISRCV8bdXli8j10Pmg8jlbevSKl4Z5FG2BVw/Cl8rQ5tBBoCzFsUPnnp9A29G8QP OqRhbwxtkSm67BMJAYdHnhjp/l0AOEbmetTGpna+R06hirOuXhR3vc6YXZxhQjff LmKaqfG5YchRALS1fNDsRUNIkQxVJade+tOUG+V4WbxHQKWX7Ghu5EDlt2/x7P0p +XLPE48HoNQLQOJ+pgIOkaEDl7WLfGhoEtEgprZBuEP2h39xcdbYJyF10ZAAR4UZ FF6J9lDHbf7v1uqD2YnAQJQ6jJ06CvN6/s6SdiJnCWSs5cYRW0fnYigSIuwAgGHZ c/QFECoGEflXGGuqZDl5iXiIjhWKzH2nADSVEs7maP47vapcMWb9gA7VBNoOr5M0 IXuFo1khChF4V2pxqlDj3H5TkDlFENYT/Wjh+vvjx8XplKCRKaSh+LaZ39hja61V dWH7BPecS44h4KXx =tFdl -----END PGP SIGNATURE----- Merge tag 'kbuild-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Generate a list of built DTB files (arch/*/boot/dts/dtbs-list) - Use more threads when building Debian packages in parallel - Fix warnings shown during the RPM kernel package uninstallation - Change OBJECT_FILES_NON_STANDARD_*.o etc. to take a relative path to Makefile - Support GCC's -fmin-function-alignment flag - Fix a null pointer dereference bug in modpost - Add the DTB support to the RPM package - Various fixes and cleanups in Kconfig * tag 'kbuild-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (67 commits) kconfig: tests: test dependency after shuffling choices kconfig: tests: add a test for randconfig with dependent choices kconfig: tests: support KCONFIG_SEED for the randconfig runner kbuild: rpm-pkg: add dtb files in kernel rpm kconfig: remove unneeded menu_is_visible() call in conf_write_defconfig() kconfig: check prompt for choice while parsing kconfig: lxdialog: remove unused dialog colors kconfig: lxdialog: fix button color for blackbg theme modpost: fix null pointer dereference kbuild: remove GCC's default -Wpacked-bitfield-compat flag kbuild: unexport abs_srctree and abs_objtree kbuild: Move -Wenum-{compare-conditional,enum-conversion} into W=1 kconfig: remove named choice support kconfig: use linked list in get_symbol_str() to iterate over menus kconfig: link menus to a symbol kbuild: fix inconsistent indentation in top Makefile kbuild: Use -fmin-function-alignment when available alpha: merge two entries for CONFIG_ALPHA_GAMMA alpha: merge two entries for CONFIG_ALPHA_EV4 kbuild: change DTC_FLAGS_<basetarget>.o to take the path relative to $(obj) ...	2024-03-21 14:41:00 -07:00
Linus Torvalds	4f712ee0cb	S390: ... * Changes to FPU handling came in via the main s390 pull request * Only deliver to the guest the SCLP events that userspace has requested. * More virtual vs physical address fixes (only a cleanup since virtual and physical address spaces are currently the same). * Fix selftests undefined behavior. x86: * Fix a restriction that the guest can't program a PMU event whose encoding matches an architectural event that isn't included in the guest CPUID. The enumeration of an architectural event only says that if a CPU supports an architectural event, then the event can be programmed *using the architectural encoding*. The enumeration does NOT say anything about the encoding when the CPU doesn't report support the event *in general*. It might support it, and it might support it using the same encoding that made it into the architectural PMU spec. * Fix a variety of bugs in KVM's emulation of RDPMC (more details on individual commits) and add a selftest to verify KVM correctly emulates RDMPC, counter availability, and a variety of other PMC-related behaviors that depend on guest CPUID and therefore are easier to validate with selftests than with custom guests (aka kvm-unit-tests). * Zero out PMU state on AMD if the virtual PMU is disabled, it does not cause any bug but it wastes time in various cases where KVM would check if a PMC event needs to be synthesized. * Optimize triggering of emulated events, with a nice ~10% performance improvement in VM-Exit microbenchmarks when a vPMU is exposed to the guest. * Tighten the check for "PMI in guest" to reduce false positives if an NMI arrives in the host while KVM is handling an IRQ VM-Exit. * Fix a bug where KVM would report stale/bogus exit qualification information when exiting to userspace with an internal error exit code. * Add a VMX flag in /proc/cpuinfo to report 5-level EPT support. * Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for read, e.g. to avoid serializing vCPUs when userspace deletes a memslot. * Tear down TDP MMU page tables at 4KiB granularity (used to be 1GiB). KVM doesn't support yielding in the middle of processing a zap, and 1GiB granularity resulted in multi-millisecond lags that are quite impolite for CONFIG_PREEMPT kernels. * Allocate write-tracking metadata on-demand to avoid the memory overhead when a kernel is built with i915 virtualization support but the workloads use neither shadow paging nor i915 virtualization. * Explicitly initialize a variety of on-stack variables in the emulator that triggered KMSAN false positives. * Fix the debugregs ABI for 32-bit KVM. * Rework the "force immediate exit" code so that vendor code ultimately decides how and when to force the exit, which allowed some optimization for both Intel and AMD. * Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if vCPU creation ultimately failed, causing extra unnecessary work. * Cleanup the logic for checking if the currently loaded vCPU is in-kernel. * Harden against underflowing the active mmu_notifier invalidation count, so that "bad" invalidations (usually due to bugs elsehwere in the kernel) are detected earlier and are less likely to hang the kernel. x86 Xen emulation: * Overlay pages can now be cached based on host virtual address, instead of guest physical addresses. This removes the need to reconfigure and invalidate the cache if the guest changes the gpa but the underlying host virtual address remains the same. * When possible, use a single host TSC value when computing the deadline for Xen timers in order to improve the accuracy of the timer emulation. * Inject pending upcall events when the vCPU software-enables its APIC to fix a bug where an upcall can be lost (and to follow Xen's behavior). * Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen events fails, e.g. if the guest has aliased xAPIC IDs. RISC-V: * Support exception and interrupt handling in selftests * New self test for RISC-V architectural timer (Sstc extension) * New extension support (Ztso, Zacas) * Support userspace emulation of random number seed CSRs. ARM: * Infrastructure for building KVM's trap configuration based on the architectural features (or lack thereof) advertised in the VM's ID registers * Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to x86's WC) at stage-2, improving the performance of interacting with assigned devices that can tolerate it * Conversion of KVM's representation of LPIs to an xarray, utilized to address serialization some of the serialization on the LPI injection path * Support for _architectural_ VHE-only systems, advertised through the absence of FEAT_E2H0 in the CPU's ID register * Miscellaneous cleanups, fixes, and spelling corrections to KVM and selftests LoongArch: * Set reserved bits as zero in CPUCFG. * Start SW timer only when vcpu is blocking. * Do not restart SW timer when it is expired. * Remove unnecessary CSR register saving during enter guest. * Misc cleanups and fixes as usual. Generic: * cleanup Kconfig by removing CONFIG_HAVE_KVM, which was basically always true on all architectures except MIPS (where Kconfig determines the available depending on CPU capabilities). It is replaced either by an architecture-dependent symbol for MIPS, and IS_ENABLED(CONFIG_KVM) everywhere else. * Factor common "select" statements in common code instead of requiring each architecture to specify it * Remove thoroughly obsolete APIs from the uapi headers. * Move architecture-dependent stuff to uapi/asm/kvm.h * Always flush the async page fault workqueue when a work item is being removed, especially during vCPU destruction, to ensure that there are no workers running in KVM code when all references to KVM-the-module are gone, i.e. to prevent a very unlikely use-after-free if kvm.ko is unloaded. * Grab a reference to the VM's mm_struct in the async #PF worker itself instead of gifting the worker a reference, so that there's no need to remember to *conditionally* clean up after the worker. Selftests: * Reduce boilerplate especially when utilize selftest TAP infrastructure. * Add basic smoke tests for SEV and SEV-ES, along with a pile of library support for handling private/encrypted/protected memory. * Fix benign bugs where tests neglect to close() guest_memfd files. -----BEGIN PGP SIGNATURE----- iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmX0iP8UHHBib256aW5p QHJlZGhhdC5jb20ACgkQv/vSX3jHroND7wf+JZoNvwZ+bmwWe/4jn/YwNoYi/C5z eypn8M1gsWEccpCpqPBwznVm9T29rF4uOlcMvqLEkHfTpaL1EKUUjP1lXPz/ileP 6a2RdOGxAhyTiFC9fjy+wkkjtLbn1kZf6YsS0hjphP9+w0chNbdn0w81dFVnXryd j7XYI8R/bFAthNsJOuZXSEjCfIHxvTTG74OrTf1B1FEBB+arPmrgUeJftMVhffQK Sowgg8L/Ii/x6fgV5NZQVSIyVf1rp8z7c6UaHT4Fwb0+RAMW8p9pYv9Qp1YkKp8y 5j0V9UzOHP7FRaYimZ5BtwQoqiZXYylQ+VuU/Y2f4X85cvlLzSqxaEMAPA== =mqOV -----END PGP SIGNATURE----- Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm Pull kvm updates from Paolo Bonzini: "S390: - Changes to FPU handling came in via the main s390 pull request - Only deliver to the guest the SCLP events that userspace has requested - More virtual vs physical address fixes (only a cleanup since virtual and physical address spaces are currently the same) - Fix selftests undefined behavior x86: - Fix a restriction that the guest can't program a PMU event whose encoding matches an architectural event that isn't included in the guest CPUID. The enumeration of an architectural event only says that if a CPU supports an architectural event, then the event can be programmed *using the architectural encoding*. The enumeration does NOT say anything about the encoding when the CPU doesn't report support the event *in general*. It might support it, and it might support it using the same encoding that made it into the architectural PMU spec - Fix a variety of bugs in KVM's emulation of RDPMC (more details on individual commits) and add a selftest to verify KVM correctly emulates RDMPC, counter availability, and a variety of other PMC-related behaviors that depend on guest CPUID and therefore are easier to validate with selftests than with custom guests (aka kvm-unit-tests) - Zero out PMU state on AMD if the virtual PMU is disabled, it does not cause any bug but it wastes time in various cases where KVM would check if a PMC event needs to be synthesized - Optimize triggering of emulated events, with a nice ~10% performance improvement in VM-Exit microbenchmarks when a vPMU is exposed to the guest - Tighten the check for "PMI in guest" to reduce false positives if an NMI arrives in the host while KVM is handling an IRQ VM-Exit - Fix a bug where KVM would report stale/bogus exit qualification information when exiting to userspace with an internal error exit code - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support - Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for read, e.g. to avoid serializing vCPUs when userspace deletes a memslot - Tear down TDP MMU page tables at 4KiB granularity (used to be 1GiB). KVM doesn't support yielding in the middle of processing a zap, and 1GiB granularity resulted in multi-millisecond lags that are quite impolite for CONFIG_PREEMPT kernels - Allocate write-tracking metadata on-demand to avoid the memory overhead when a kernel is built with i915 virtualization support but the workloads use neither shadow paging nor i915 virtualization - Explicitly initialize a variety of on-stack variables in the emulator that triggered KMSAN false positives - Fix the debugregs ABI for 32-bit KVM - Rework the "force immediate exit" code so that vendor code ultimately decides how and when to force the exit, which allowed some optimization for both Intel and AMD - Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if vCPU creation ultimately failed, causing extra unnecessary work - Cleanup the logic for checking if the currently loaded vCPU is in-kernel - Harden against underflowing the active mmu_notifier invalidation count, so that "bad" invalidations (usually due to bugs elsehwere in the kernel) are detected earlier and are less likely to hang the kernel x86 Xen emulation: - Overlay pages can now be cached based on host virtual address, instead of guest physical addresses. This removes the need to reconfigure and invalidate the cache if the guest changes the gpa but the underlying host virtual address remains the same - When possible, use a single host TSC value when computing the deadline for Xen timers in order to improve the accuracy of the timer emulation - Inject pending upcall events when the vCPU software-enables its APIC to fix a bug where an upcall can be lost (and to follow Xen's behavior) - Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen events fails, e.g. if the guest has aliased xAPIC IDs RISC-V: - Support exception and interrupt handling in selftests - New self test for RISC-V architectural timer (Sstc extension) - New extension support (Ztso, Zacas) - Support userspace emulation of random number seed CSRs ARM: - Infrastructure for building KVM's trap configuration based on the architectural features (or lack thereof) advertised in the VM's ID registers - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to x86's WC) at stage-2, improving the performance of interacting with assigned devices that can tolerate it - Conversion of KVM's representation of LPIs to an xarray, utilized to address serialization some of the serialization on the LPI injection path - Support for _architectural_ VHE-only systems, advertised through the absence of FEAT_E2H0 in the CPU's ID register - Miscellaneous cleanups, fixes, and spelling corrections to KVM and selftests LoongArch: - Set reserved bits as zero in CPUCFG - Start SW timer only when vcpu is blocking - Do not restart SW timer when it is expired - Remove unnecessary CSR register saving during enter guest - Misc cleanups and fixes as usual Generic: - Clean up Kconfig by removing CONFIG_HAVE_KVM, which was basically always true on all architectures except MIPS (where Kconfig determines the available depending on CPU capabilities). It is replaced either by an architecture-dependent symbol for MIPS, and IS_ENABLED(CONFIG_KVM) everywhere else - Factor common "select" statements in common code instead of requiring each architecture to specify it - Remove thoroughly obsolete APIs from the uapi headers - Move architecture-dependent stuff to uapi/asm/kvm.h - Always flush the async page fault workqueue when a work item is being removed, especially during vCPU destruction, to ensure that there are no workers running in KVM code when all references to KVM-the-module are gone, i.e. to prevent a very unlikely use-after-free if kvm.ko is unloaded - Grab a reference to the VM's mm_struct in the async #PF worker itself instead of gifting the worker a reference, so that there's no need to remember to *conditionally* clean up after the worker Selftests: - Reduce boilerplate especially when utilize selftest TAP infrastructure - Add basic smoke tests for SEV and SEV-ES, along with a pile of library support for handling private/encrypted/protected memory - Fix benign bugs where tests neglect to close() guest_memfd files" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits) selftests: kvm: remove meaningless assignments in Makefiles KVM: riscv: selftests: Add Zacas extension to get-reg-list test RISC-V: KVM: Allow Zacas extension for Guest/VM KVM: riscv: selftests: Add Ztso extension to get-reg-list test RISC-V: KVM: Allow Ztso extension for Guest/VM RISC-V: KVM: Forward SEED CSR access to user space KVM: riscv: selftests: Add sstc timer test KVM: riscv: selftests: Change vcpu_has_ext to a common function KVM: riscv: selftests: Add guest helper to get vcpu id KVM: riscv: selftests: Add exception handling support LoongArch: KVM: Remove unnecessary CSR register saving during enter guest LoongArch: KVM: Do not restart SW timer when it is expired LoongArch: KVM: Start SW timer only when vcpu is blocking LoongArch: KVM: Set reserved bits as zero in CPUCFG KVM: selftests: Explicitly close guest_memfd files in some gmem tests KVM: x86/xen: fix recursive deadlock in timer injection KVM: pfncache: simplify locking and make more self-contained KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled KVM: x86/xen: improve accuracy of Xen timers ...	2024-03-15 13:03:13 -07:00
Linus Torvalds	902861e34c	- Sumanth Korikkar has taught s390 to allocate hotplug-time page frames ... from hotplugged memory rather than only from main memory. Series "implement "memmap on memory" feature on s390". - More folio conversions from Matthew Wilcox in the series "Convert memcontrol charge moving to use folios" "mm: convert mm counter to take a folio" - Chengming Zhou has optimized zswap's rbtree locking, providing significant reductions in system time and modest but measurable reductions in overall runtimes. The series is "mm/zswap: optimize the scalability of zswap rb-tree". - Chengming Zhou has also provided the series "mm/zswap: optimize zswap lru list" which provides measurable runtime benefits in some swap-intensive situations. - And Chengming Zhou further optimizes zswap in the series "mm/zswap: optimize for dynamic zswap_pools". Measured improvements are modest. - zswap cleanups and simplifications from Yosry Ahmed in the series "mm: zswap: simplify zswap_swapoff()". - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has contributed several DAX cleanups as well as adding a sysfs tunable to control the memmap_on_memory setting when the dax device is hotplugged as system memory. - Johannes Weiner has added the large series "mm: zswap: cleanups", which does that. - More DAMON work from SeongJae Park in the series "mm/damon: make DAMON debugfs interface deprecation unignorable" "selftests/damon: add more tests for core functionalities and corner cases" "Docs/mm/damon: misc readability improvements" "mm/damon: let DAMOS feeds and tame/auto-tune itself" - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs extension" Rakie Kim has developed a new mempolicy interleaving policy wherein we allocate memory across nodes in a weighted fashion rather than uniformly. This is beneficial in heterogeneous memory environments appearing with CXL. - Christophe Leroy has contributed some cleanup and consolidation work against the ARM pagetable dumping code in the series "mm: ptdump: Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute". - Luis Chamberlain has added some additional xarray selftesting in the series "test_xarray: advanced API multi-index tests". - Muhammad Usama Anjum has reworked the selftest code to make its human-readable output conform to the TAP ("Test Anything Protocol") format. Amongst other things, this opens up the use of third-party tools to parse and process out selftesting results. - Ryan Roberts has added fork()-time PTE batching of THP ptes in the series "mm/memory: optimize fork() with PTE-mapped THP". Mainly targeted at arm64, this significantly speeds up fork() when the process has a large number of pte-mapped folios. - David Hildenbrand also gets in on the THP pte batching game in his series "mm/memory: optimize unmap/zap with PTE-mapped THP". It implements batching during munmap() and other pte teardown situations. The microbenchmark improvements are nice. - And in the series "Transparent Contiguous PTEs for User Mappings" Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte mappings"). Kernel build times on arm64 improved nicely. Ryan's series "Address some contpte nits" provides some followup work. - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has fixed an obscure hugetlb race which was causing unnecessary page faults. He has also added a reproducer under the selftest code. - In the series "selftests/mm: Output cleanups for the compaction test", Mark Brown did what the title claims. - Kinsey Ho has added the series "mm/mglru: code cleanup and refactoring". - Even more zswap material from Nhat Pham. The series "fix and extend zswap kselftests" does as claimed. - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX regression" Mathieu Desnoyers has cleaned up and fixed rather a mess in our handling of DAX on archiecctures which have virtually aliasing data caches. The arm architecture is the main beneficiary. - Lokesh Gidra's series "per-vma locks in userfaultfd" provides dramatic improvements in worst-case mmap_lock hold times during certain userfaultfd operations. - Some page_owner enhancements and maintenance work from Oscar Salvador in his series "page_owner: print stacks and their outstanding allocations" "page_owner: Fixup and cleanup" - Uladzislau Rezki has contributed some vmalloc scalability improvements in his series "Mitigate a vmap lock contention". It realizes a 12x improvement for a certain microbenchmark. - Some kexec/crash cleanup work from Baoquan He in the series "Split crash out from kexec and clean up related config items". - Some zsmalloc maintenance work from Chengming Zhou in the series "mm/zsmalloc: fix and optimize objects/page migration" "mm/zsmalloc: some cleanup for get/set_zspage_mapping()" - Zi Yan has taught the MM to perform compaction on folios larger than order=0. This a step along the path to implementaton of the merging of large anonymous folios. The series is named "Enable >0 order folio memory compaction". - Christoph Hellwig has done quite a lot of cleanup work in the pagecache writeback code in his series "convert write_cache_pages() to an iterator". - Some modest hugetlb cleanups and speedups in Vishal Moola's series "Handle hugetlb faults under the VMA lock". - Zi Yan has changed the page splitting code so we can split huge pages into sizes other than order-0 to better utilize large folios. The series is named "Split a folio to any lower order folios". - David Hildenbrand has contributed the series "mm: remove total_mapcount()", a cleanup. - Matthew Wilcox has sought to improve the performance of bulk memory freeing in his series "Rearrange batched folio freeing". - Gang Li's series "hugetlb: parallelize hugetlb page init on boot" provides large improvements in bootup times on large machines which are configured to use large numbers of hugetlb pages. - Matthew Wilcox's series "PageFlags cleanups" does that. - Qi Zheng's series "minor fixes and supplement for ptdesc" does that also. S390 is affected. - Cleanups to our pagemap utility functions from Peter Xu in his series "mm/treewide: Replace pXd_large() with pXd_leaf()". - Nico Pache has fixed a few things with our hugepage selftests in his series "selftests/mm: Improve Hugepage Test Handling in MM Selftests". - Also, of course, many singleton patches to many things. Please see the individual changelogs for details. -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZfJpPQAKCRDdBJ7gKXxA joxeAP9TrcMEuHnLmBlhIXkWbIR4+ki+pA3v+gNTlJiBhnfVSgD9G55t1aBaRplx TMNhHfyiHYDTx/GAV9NXW84tasJSDgA= =TG55 -----END PGP SIGNATURE----- Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames from hotplugged memory rather than only from main memory. Series "implement "memmap on memory" feature on s390". - More folio conversions from Matthew Wilcox in the series "Convert memcontrol charge moving to use folios" "mm: convert mm counter to take a folio" - Chengming Zhou has optimized zswap's rbtree locking, providing significant reductions in system time and modest but measurable reductions in overall runtimes. The series is "mm/zswap: optimize the scalability of zswap rb-tree". - Chengming Zhou has also provided the series "mm/zswap: optimize zswap lru list" which provides measurable runtime benefits in some swap-intensive situations. - And Chengming Zhou further optimizes zswap in the series "mm/zswap: optimize for dynamic zswap_pools". Measured improvements are modest. - zswap cleanups and simplifications from Yosry Ahmed in the series "mm: zswap: simplify zswap_swapoff()". - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has contributed several DAX cleanups as well as adding a sysfs tunable to control the memmap_on_memory setting when the dax device is hotplugged as system memory. - Johannes Weiner has added the large series "mm: zswap: cleanups", which does that. - More DAMON work from SeongJae Park in the series "mm/damon: make DAMON debugfs interface deprecation unignorable" "selftests/damon: add more tests for core functionalities and corner cases" "Docs/mm/damon: misc readability improvements" "mm/damon: let DAMOS feeds and tame/auto-tune itself" - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs extension" Rakie Kim has developed a new mempolicy interleaving policy wherein we allocate memory across nodes in a weighted fashion rather than uniformly. This is beneficial in heterogeneous memory environments appearing with CXL. - Christophe Leroy has contributed some cleanup and consolidation work against the ARM pagetable dumping code in the series "mm: ptdump: Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute". - Luis Chamberlain has added some additional xarray selftesting in the series "test_xarray: advanced API multi-index tests". - Muhammad Usama Anjum has reworked the selftest code to make its human-readable output conform to the TAP ("Test Anything Protocol") format. Amongst other things, this opens up the use of third-party tools to parse and process out selftesting results. - Ryan Roberts has added fork()-time PTE batching of THP ptes in the series "mm/memory: optimize fork() with PTE-mapped THP". Mainly targeted at arm64, this significantly speeds up fork() when the process has a large number of pte-mapped folios. - David Hildenbrand also gets in on the THP pte batching game in his series "mm/memory: optimize unmap/zap with PTE-mapped THP". It implements batching during munmap() and other pte teardown situations. The microbenchmark improvements are nice. - And in the series "Transparent Contiguous PTEs for User Mappings" Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte mappings"). Kernel build times on arm64 improved nicely. Ryan's series "Address some contpte nits" provides some followup work. - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has fixed an obscure hugetlb race which was causing unnecessary page faults. He has also added a reproducer under the selftest code. - In the series "selftests/mm: Output cleanups for the compaction test", Mark Brown did what the title claims. - Kinsey Ho has added the series "mm/mglru: code cleanup and refactoring". - Even more zswap material from Nhat Pham. The series "fix and extend zswap kselftests" does as claimed. - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX regression" Mathieu Desnoyers has cleaned up and fixed rather a mess in our handling of DAX on archiecctures which have virtually aliasing data caches. The arm architecture is the main beneficiary. - Lokesh Gidra's series "per-vma locks in userfaultfd" provides dramatic improvements in worst-case mmap_lock hold times during certain userfaultfd operations. - Some page_owner enhancements and maintenance work from Oscar Salvador in his series "page_owner: print stacks and their outstanding allocations" "page_owner: Fixup and cleanup" - Uladzislau Rezki has contributed some vmalloc scalability improvements in his series "Mitigate a vmap lock contention". It realizes a 12x improvement for a certain microbenchmark. - Some kexec/crash cleanup work from Baoquan He in the series "Split crash out from kexec and clean up related config items". - Some zsmalloc maintenance work from Chengming Zhou in the series "mm/zsmalloc: fix and optimize objects/page migration" "mm/zsmalloc: some cleanup for get/set_zspage_mapping()" - Zi Yan has taught the MM to perform compaction on folios larger than order=0. This a step along the path to implementaton of the merging of large anonymous folios. The series is named "Enable >0 order folio memory compaction". - Christoph Hellwig has done quite a lot of cleanup work in the pagecache writeback code in his series "convert write_cache_pages() to an iterator". - Some modest hugetlb cleanups and speedups in Vishal Moola's series "Handle hugetlb faults under the VMA lock". - Zi Yan has changed the page splitting code so we can split huge pages into sizes other than order-0 to better utilize large folios. The series is named "Split a folio to any lower order folios". - David Hildenbrand has contributed the series "mm: remove total_mapcount()", a cleanup. - Matthew Wilcox has sought to improve the performance of bulk memory freeing in his series "Rearrange batched folio freeing". - Gang Li's series "hugetlb: parallelize hugetlb page init on boot" provides large improvements in bootup times on large machines which are configured to use large numbers of hugetlb pages. - Matthew Wilcox's series "PageFlags cleanups" does that. - Qi Zheng's series "minor fixes and supplement for ptdesc" does that also. S390 is affected. - Cleanups to our pagemap utility functions from Peter Xu in his series "mm/treewide: Replace pXd_large() with pXd_leaf()". - Nico Pache has fixed a few things with our hugepage selftests in his series "selftests/mm: Improve Hugepage Test Handling in MM Selftests". - Also, of course, many singleton patches to many things. Please see the individual changelogs for details. * tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits) mm/zswap: remove the memcpy if acomp is not sleepable crypto: introduce: acomp_is_async to expose if comp drivers might sleep memtest: use {READ,WRITE}_ONCE in memory scanning mm: prohibit the last subpage from reusing the entire large folio mm: recover pud_leaf() definitions in nopmd case selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements selftests/mm: skip uffd hugetlb tests with insufficient hugepages selftests/mm: dont fail testsuite due to a lack of hugepages mm/huge_memory: skip invalid debugfs new_order input for folio split mm/huge_memory: check new folio order when split a folio mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure mm: add an explicit smp_wmb() to UFFDIO_CONTINUE mm: fix list corruption in put_pages_list mm: remove folio from deferred split list before uncharging it filemap: avoid unnecessary major faults in filemap_fault() mm,page_owner: drop unnecessary check mm,page_owner: check for null stack_record before bumping its refcount mm: swap: fix race between free_swap_and_cache() and swapoff() mm/treewide: align up pXd_leaf() retval across archs mm/treewide: drop pXd_large() ...	2024-03-14 17:43:30 -07:00
Linus Torvalds	216532e147	hardening updates for v6.9-rc1 ... - string.h and related header cleanups (Tanzir Hasan, Andy Shevchenko) - VMCI memcpy() usage and struct_size() cleanups (Vasiliy Kovalev, Harshit Mogalapalli) - selftests/powerpc: Fix load_unaligned_zeropad build failure (Michael Ellerman) - hardened Kconfig fragment updates (Marco Elver, Lukas Bulwahn) - Handle tail call optimization better in LKDTM (Douglas Anderson) - Use long form types in overflow.h (Andy Shevchenko) - Add flags param to string_get_size() (Andy Shevchenko) - Add Coccinelle script for potential struct_size() use (Jacob Keller) - Fix objtool corner case under KCFI (Josh Poimboeuf) - Drop 13 year old backward compat CAP_SYS_ADMIN check (Jingzi Meng) - Add str_plural() helper (Michal Wajdeczko, Kees Cook) - Ignore relocations in .notes section - Add comments to explain how __is_constexpr() works - Fix m68k stack alignment expectations in stackinit Kunit test - Convert string selftests to KUnit - Add KUnit tests for fortified string functions - Improve reporting during fortified string warnings - Allow non-type arg to type_max() and type_min() - Allow strscpy() to be called with only 2 arguments - Add binary mode to leaking_addresses scanner - Various small cleanups to leaking_addresses scanner - Adding wrapping_*() arithmetic helper - Annotate initial signed integer wrap-around in refcount_t - Add explicit UBSAN section to MAINTAINERS - Fix UBSAN self-test warnings - Simplify UBSAN build via removal of CONFIG_UBSAN_SANITIZE_ALL - Reintroduce UBSAN's signed overflow sanitizer -----BEGIN PGP SIGNATURE----- iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAmXvm5kWHGtlZXNjb29r QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJiQqD/4mM6SWZpYHKlR1nEiqIyz7Hqr9 g4oguuw6HIVNJXLyeBI5Hd43CTeHPA0e++EETqhUAt7HhErxfYJY+JB221nRYmu+ zhhQ7N/xbTMV/Je7AR03kQjhiMm8LyEcM2X4BNrsAcoCieQzmO3g0zSp8ISzLUE0 PEEmf1lOzMe3gK2KOFCPt5Hiz9sGWyN6at+BQubY18tQGtjEXYAQNXkpD5qhGn4a EF693r/17wmc8hvSsjf4AGaWy1k8crG0WfpMCZsaqftjj0BbvOC60IDyx4eFjpcy tGyAJKETq161AkCdNweIh2Q107fG3tm0fcvw2dv8Wt1eQCko6M8dUGCBinQs/thh TexjJFS/XbSz+IvxLqgU+C5qkOP23E0M9m1dbIbOFxJAya/5n16WOBlGr3ae2Wdq /+t8wVSJw3vZiku5emWdFYP1VsdIHUjVa5QizFaaRhzLGRwhxVV49SP4IQC/5oM5 3MAgNOFTP6yRQn9Y9wP+SZs+SsfaIE7yfKa9zOi4S+Ve+LI2v4YFhh8NCRiLkeWZ R1dhp8Pgtuq76f/v0qUaWcuuVeGfJ37M31KOGIhi1sI/3sr7UMrngL8D1+F8UZMi zcLu+x4GtfUZCHl6znx1rNUBqE5S/5ndVhLpOqfCXKaQ+RAm7lkOJ3jXE2VhNkhp yVEmeSOLnlCaQjZvXQ== =OP+o -----END PGP SIGNATURE----- Merge tag 'hardening-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: "As is pretty normal for this tree, there are changes all over the place, especially for small fixes, selftest improvements, and improved macro usability. Some header changes ended up landing via this tree as they depended on the string header cleanups. Also, a notable set of changes is the work for the reintroduction of the UBSAN signed integer overflow sanitizer so that we can continue to make improvements on the compiler side to make this sanitizer a more viable future security hardening option. Summary: - string.h and related header cleanups (Tanzir Hasan, Andy Shevchenko) - VMCI memcpy() usage and struct_size() cleanups (Vasiliy Kovalev, Harshit Mogalapalli) - selftests/powerpc: Fix load_unaligned_zeropad build failure (Michael Ellerman) - hardened Kconfig fragment updates (Marco Elver, Lukas Bulwahn) - Handle tail call optimization better in LKDTM (Douglas Anderson) - Use long form types in overflow.h (Andy Shevchenko) - Add flags param to string_get_size() (Andy Shevchenko) - Add Coccinelle script for potential struct_size() use (Jacob Keller) - Fix objtool corner case under KCFI (Josh Poimboeuf) - Drop 13 year old backward compat CAP_SYS_ADMIN check (Jingzi Meng) - Add str_plural() helper (Michal Wajdeczko, Kees Cook) - Ignore relocations in .notes section - Add comments to explain how __is_constexpr() works - Fix m68k stack alignment expectations in stackinit Kunit test - Convert string selftests to KUnit - Add KUnit tests for fortified string functions - Improve reporting during fortified string warnings - Allow non-type arg to type_max() and type_min() - Allow strscpy() to be called with only 2 arguments - Add binary mode to leaking_addresses scanner - Various small cleanups to leaking_addresses scanner - Adding wrapping_*() arithmetic helper - Annotate initial signed integer wrap-around in refcount_t - Add explicit UBSAN section to MAINTAINERS - Fix UBSAN self-test warnings - Simplify UBSAN build via removal of CONFIG_UBSAN_SANITIZE_ALL - Reintroduce UBSAN's signed overflow sanitizer" * tag 'hardening-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (51 commits) selftests/powerpc: Fix load_unaligned_zeropad build failure string: Convert helpers selftest to KUnit string: Convert selftest to KUnit sh: Fix build with CONFIG_UBSAN=y compiler.h: Explain how __is_constexpr() works overflow: Allow non-type arg to type_max() and type_min() VMCI: Fix possible memcpy() run-time warning in vmci_datagram_invoke_guest_handler() lib/string_helpers: Add flags param to string_get_size() x86, relocs: Ignore relocations in .notes section objtool: Fix UNWIND_HINT_{SAVE,RESTORE} across basic blocks overflow: Use POD in check_shl_overflow() lib: stackinit: Adjust target string to 8 bytes for m68k sparc: vdso: Disable UBSAN instrumentation kernel.h: Move lib/cmdline.c prototypes to string.h leaking_addresses: Provide mechanism to scan binary files leaking_addresses: Ignore input device status lines leaking_addresses: Use File::Temp for /tmp files MAINTAINERS: Update LEAKING_ADDRESSES details fortify: Improve buffer overflow reporting fortify: Add KUnit tests for runtime overflows ...	2024-03-12 14:49:30 -07:00
Linus Torvalds	0e33cf955f	* Mitigate RFDS vulnerability ... -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmXvZgoACgkQaDWVMHDJ krC2Eg//aZKBp97/DSzRqXKDwJzVUr0sGJ9cii0gVT1sI+1U6ZZCh/roVH4xOT5/ HqtOOnQ+X0mwUx2VG3Yv2VPI7VW68sJ3/y9D8R4tnMEsyQ4CmDw96Pre3NyKr/Av jmW7SK94fOkpNFJOMk3zpk7GtRUlCsVkS1P61dOmMYduguhel/V20rWlx83BgnAY Rf/c3rBjqe8Ri3rzBP5icY/d6OgwoafuhME31DD/j6oKOh+EoQBvA4urj46yMTMX /mrK7hCm/wqwuOOvgGbo7sfZNBLCYy3SZ3EyF4beDERhPF1DaSvCwOULpGVJroqu SelFsKXAtEbYrDgsan+MYlx3bQv43q7PbHska1gjkH91plO4nAsssPr5VsusUKmT sq8jyBaauZb40oLOSgooL4RqAHrfs8q5695Ouwh/DB/XovMezUI1N/BkpGFmqpJI o2xH9P5q520pkB8pFhN9TbRuFSGe/dbWC24QTq1DUajo3M3RwcwX6ua9hoAKLtDF pCV5DNcVcXHD3Cxp0M5dQ5JEAiCnW+ZpUWgxPQamGDNW5PEvjDmFwql2uWw/qOuW lkheOIffq8ejUBQFbN8VXfIzzeeKQNFiIcViaqGITjIwhqdHAzVi28OuIGwtdh3g ywLzSC8yvyzgKrNBgtFMr3ucKN0FoPxpBro253xt2H7w8srXW64= =5V9t -----END PGP SIGNATURE----- Merge tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RFDS mitigation from Dave Hansen: "RFDS is a CPU vulnerability that may allow a malicious userspace to infer stale register values from kernel space. Kernel registers can have all kinds of secrets in them so the mitigation is basically to wait until the kernel is about to return to userspace and has user values in the registers. At that point there is little chance of kernel secrets ending up in the registers and the microarchitectural state can be cleared. This leverages some recent robustness fixes for the existing MDS vulnerability. Both MDS and RFDS use the VERW instruction for mitigation" * tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: KVM/x86: Export RFDS_NO and RFDS_CLEAR to guests x86/rfds: Mitigate Register File Data Sampling (RFDS) Documentation/hw-vuln: Add documentation for RFDS x86/mmio: Disable KVM mitigation when X86_FEATURE_CLEAR_CPU_BUF is set	2024-03-12 09:31:39 -07:00
Linus Torvalds	685d982112	Core x86 changes for v6.9: ... - The biggest change is the rework of the percpu code, to support the 'Named Address Spaces' GCC feature, by Uros Bizjak: - This allows C code to access GS and FS segment relative memory via variables declared with such attributes, which allows the compiler to better optimize those accesses than the previous inline assembly code. - The series also includes a number of micro-optimizations for various percpu access methods, plus a number of cleanups of %gs accesses in assembly code. - These changes have been exposed to linux-next testing for the last ~5 months, with no known regressions in this area. - Fix/clean up __switch_to()'s broken but accidentally working handling of FPU switching - which also generates better code. - Propagate more RIP-relative addressing in assembly code, to generate slightly better code. - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to make it easier for distros to follow & maintain these options. - Rework the x86 idle code to cure RCU violations and to clean up the logic. - Clean up the vDSO Makefile logic. - Misc cleanups and fixes. [ Please note that there's a higher number of merge commits in this branch (three) than is usual in x86 topic trees. This happened due to the long testing lifecycle of the percpu changes that involved 3 merge windows, which generated a longer history and various interactions with other core x86 changes that we felt better about to carry in a single branch. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmXvB0gRHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1jUqRAAqnEQPiabF5acQlHrwviX+cjSobDlqtH5 9q2AQy9qaEHapzD0XMOxvFye6XIvehGOGxSPvk6CoviSxBND8rb56lvnsEZuLeBV Bo5QSIL2x42Zrvo11iPHwgXZfTIusU90sBuKDRFkYBAxY3HK2naMDZe8MAsYCUE9 nwgHF8DDc/NYiSOXV8kosWoWpNIkoK/STyH5bvTQZMqZcwyZ49AIeP1jGZb/prbC e/rbnlrq5Eu6brpM7xo9kELO0Vhd34urV14KrrIpdkmUKytW2KIsyvW8D6fqgDBj NSaQLLcz0pCXbhF+8Nqvdh/1coR4L7Ymt08P1rfEjCsQgb/2WnSAGUQuC5JoGzaj ngkbFcZllIbD9gNzMQ1n4Aw5TiO+l9zxCqPC/r58Uuvstr+K9QKlwnp2+B3Q73Ft rojIJ04NJL6lCHdDgwAjTTks+TD2PT/eBWsDfJ/1pnUWttmv9IjMpnXD5sbHxoiU 2RGGKnYbxXczYdq/ALYDWM6JXpfnJZcXL3jJi0IDcCSsb92xRvTANYFHnTfyzGfw EHkhbF4e4Vy9f6QOkSP3CvW5H26BmZS9DKG0J9Il5R3u2lKdfbb5vmtUmVTqHmAD Ulo5cWZjEznlWCAYSI/aIidmBsp9OAEvYd+X7Z5SBIgTfSqV7VWHGt0BfA1heiVv F/mednG0gGc= =3v4F -----END PGP SIGNATURE----- Merge tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: - The biggest change is the rework of the percpu code, to support the 'Named Address Spaces' GCC feature, by Uros Bizjak: - This allows C code to access GS and FS segment relative memory via variables declared with such attributes, which allows the compiler to better optimize those accesses than the previous inline assembly code. - The series also includes a number of micro-optimizations for various percpu access methods, plus a number of cleanups of %gs accesses in assembly code. - These changes have been exposed to linux-next testing for the last ~5 months, with no known regressions in this area. - Fix/clean up __switch_to()'s broken but accidentally working handling of FPU switching - which also generates better code - Propagate more RIP-relative addressing in assembly code, to generate slightly better code - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to make it easier for distros to follow & maintain these options - Rework the x86 idle code to cure RCU violations and to clean up the logic - Clean up the vDSO Makefile logic - Misc cleanups and fixes * tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) x86/idle: Select idle routine only once x86/idle: Let prefer_mwait_c1_over_halt() return bool x86/idle: Cleanup idle_setup() x86/idle: Clean up idle selection x86/idle: Sanitize X86_BUG_AMD_E400 handling sched/idle: Conditionally handle tick broadcast in default_idle_call() x86: Increase brk randomness entropy for 64-bit systems x86/vdso: Move vDSO to mmap region x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o x86/retpoline: Ensure default return thunk isn't used at runtime x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32 x86/vdso: Use $(addprefix ) instead of $(foreach ) x86/vdso: Simplify obj-y addition x86/vdso: Consolidate targets and clean-files x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNK x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLS ...	2024-03-11 19:53:15 -07:00
Linus Torvalds	fcc196579a	Misc cleanups, including a large series from Thomas Gleixner to ... cure Sparse warnings. Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmXvAFQRHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1hkDRAAwASVCQ88kiGqNQtHibXlK54mAFGsc0xv T8OPds15DUzoLg/y8lw0X0DHly6MdGXVmygybejNIw2BN4lhLjQ7f4Ria7rv7LDy FcI1jfvysEMyYRFHGRefb/GBFzuEfKoROwf+QylGmKz0ZK674gNMngsI9pwOBdbe wElq3IkHoNuTUfH9QA4BvqGam1n122nvVTop3g0PMHWzx9ky8hd/BEUjXFZhfINL zZk3fwUbER2QYbhHt+BN2GRbdf2BrKvqTkXpKxyXTdnpiqAo0CzBGKerZ62H82qG n737Nib1lrsfM5yDHySnau02aamRXaGvCJUd6gpac1ZmNpZMWhEOT/0Tr/Nj5ztF lUAvKqMZn/CwwQky1/XxD0LHegnve0G+syqQt/7x7o1ELdiwTzOWMCx016UeodzB yyHf3Xx9J8nt3snlrlZBaGEfegg9ePLu5Vir7iXjg3vrloUW8A+GZM62NVxF4HVV QWF80BfWf8zbLQ/OS1382t1shaioIe5pEXzIjcnyVIZCiiP2/5kP2O6P4XVbwVlo Ca5eEt8U1rtsLUZaCzI2ZRTQf/8SLMQWyaV+ZmkVwcVdFoARC31EgdE5wYYoZOf6 7Vl+rXd+rZCuTWk0ZgznCZEm75aaqukaQCBa2V8hIVociLFVzhg/Tjedv7s0CspA hNfxdN1LDZc= =0eJ7 -----END PGP SIGNATURE----- Merge tag 'x86-cleanups-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Misc cleanups, including a large series from Thomas Gleixner to cure sparse warnings" * tag 'x86-cleanups-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi: Drop unused declaration of proc_nmi_enabled() x86/callthunks: Use EXPORT_PER_CPU_SYMBOL_GPL() for per CPU variables x86/cpu: Provide a declaration for itlb_multihit_kvm_mitigation x86/cpu: Use EXPORT_PER_CPU_SYMBOL_GPL() for x86_spec_ctrl_current x86/uaccess: Add missing __force to casts in __access_ok() and valid_user_address() x86/percpu: Cure per CPU madness on UP smp: Consolidate smp_prepare_boot_cpu() x86/msr: Add missing __percpu annotations x86/msr: Prepare for including <linux/percpu.h> into <asm/msr.h> perf/x86/amd/uncore: Fix __percpu annotation x86/nmi: Remove an unnecessary IS_ENABLED(CONFIG_SMP) x86/apm_32: Remove dead function apm_get_battery_status() x86/insn-eval: Fix function param name in get_eff_addr_sib()	2024-03-11 19:37:56 -07:00
Linus Torvalds	38b334fc76	- Add the x86 part of the SEV-SNP host support. This will allow the ... kernel to be used as a KVM hypervisor capable of running SNP (Secure Nested Paging) guests. Roughly speaking, SEV-SNP is the ultimate goal of the AMD confidential computing side, providing the most comprehensive confidential computing environment up to date. This is the x86 part and there is a KVM part which did not get ready in time for the merge window so latter will be forthcoming in the next cycle. - Rework the early code's position-dependent SEV variable references in order to allow building the kernel with clang and -fPIE/-fPIC and -mcmodel=kernel - The usual set of fixes, cleanups and improvements all over the place -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmXvH0wACgkQEsHwGGHe VUrzmA//VS/n6dhHRnm/nAGngr4PeegkgV1OhyKYFfiZ272rT6P9QvblQrgcY0dc Ij1DOhEKlke51pTHvMOQ33B3P4Fuc0mx3dpCLY0up5V26kzQiKCjRKEkC4U1bcw8 W4GqMejaR89bE14bYibmwpSib9T/uVsV65eM3xf1iF5UvsnoUaTziymDoy+nb43a B1pdd5vcl4mBNqXeEvt0qjg+xkMLpWUI9tJDB8mbMl/cnIFGgMZzBaY8oktHSROK QpuUnKegOgp1RXpfLbNjmZ2Q4Rkk4MNazzDzWq3EIxaRjXL3Qp507ePK7yeA2qa0 J3jCBQc9E2j7lfrIkUgNIzOWhMAXM2YH5bvH6UrIcMi1qsWJYDmkp2MF1nUedjdf Wj16/pJbeEw1aKKIywJGwsmViSQju158vY3SzXG83U/A/Iz7zZRHFmC/ALoxZptY Bi7VhfcOSpz98PE3axnG8CvvxRDWMfzBr2FY1VmQbg6VBNo1Xl1aP/IH1I8iQNKg /laBYl/qP+1286TygF1lthYROb1lfEIJprgi2xfO6jVYUqPb7/zq2sm78qZRfm7l 25PN/oHnuidfVfI/H3hzcGubjOG9Zwra8WWYBB2EEmelf21rT0OLqq+eS4T6pxFb GNVfc0AzG77UmqbrpkAMuPqL7LrGaSee4NdU3hkEdSphlx1/YTo= =c1ps -----END PGP SIGNATURE----- Merge tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV updates from Borislav Petkov: - Add the x86 part of the SEV-SNP host support. This will allow the kernel to be used as a KVM hypervisor capable of running SNP (Secure Nested Paging) guests. Roughly speaking, SEV-SNP is the ultimate goal of the AMD confidential computing side, providing the most comprehensive confidential computing environment up to date. This is the x86 part and there is a KVM part which did not get ready in time for the merge window so latter will be forthcoming in the next cycle. - Rework the early code's position-dependent SEV variable references in order to allow building the kernel with clang and -fPIE/-fPIC and -mcmodel=kernel - The usual set of fixes, cleanups and improvements all over the place * tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) x86/sev: Disable KMSAN for memory encryption TUs x86/sev: Dump SEV_STATUS crypto: ccp - Have it depend on AMD_IOMMU iommu/amd: Fix failure return from snp_lookup_rmpentry() x86/sev: Fix position dependent variable references in startup code crypto: ccp: Make snp_range_list static x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT Documentation: virt: Fix up pre-formatted text block for SEV ioctls crypto: ccp: Add the SNP_SET_CONFIG command crypto: ccp: Add the SNP_COMMIT command crypto: ccp: Add the SNP_PLATFORM_STATUS command x86/cpufeatures: Enable/unmask SEV-SNP CPU feature KVM: SEV: Make AVIC backing, VMSA and VMCB memory allocation SNP safe crypto: ccp: Add panic notifier for SEV/SNP firmware shutdown on kdump iommu/amd: Clean up RMP entries for IOMMU pages during SNP shutdown crypto: ccp: Handle legacy SEV commands when SNP is enabled crypto: ccp: Handle non-volatile INIT_EX data when SNP is enabled crypto: ccp: Handle the legacy TMR allocation when SNP is enabled x86/sev: Introduce an SNP leaked pages list crypto: ccp: Provide an API to issue SEV and SNP commands ...	2024-03-11 17:44:11 -07:00
Linus Torvalds	720c857907	Support for x86 Fast Return and Event Delivery (FRED): ... FRED is a replacement for IDT event delivery on x86 and addresses most of the technical nightmares which IDT exposes: 1) Exception cause registers like CR2 need to be manually preserved in nested exception scenarios. 2) Hardware interrupt stack switching is suboptimal for nested exceptions as the interrupt stack mechanism rewinds the stack on each entry which requires a massive effort in the low level entry of #NMI code to handle this. 3) No hardware distinction between entry from kernel or from user which makes establishing kernel context more complex than it needs to be especially for unconditionally nestable exceptions like NMI. 4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a problem when the perf NMI takes a fault when collecting a stack trace. 5) Partial restore of ESP when returning to a 16-bit segment 6) Limitation of the vector space which can cause vector exhaustion on large systems. 7) Inability to differentiate NMI sources FRED addresses these shortcomings by: 1) An extended exception stack frame which the CPU uses to save exception cause registers. This ensures that the meta information for each exception is preserved on stack and avoids the extra complexity of preserving it in software. 2) Hardware interrupt stack switching is non-rewinding if a nested exception uses the currently interrupt stack. 3) The entry points for kernel and user context are separate and GS BASE handling which is required to establish kernel context for per CPU variable access is done in hardware. 4) NMIs are now nesting protected. They are only reenabled on the return from NMI. 5) FRED guarantees full restore of ESP 6) FRED does not put a limitation on the vector space by design because it uses a central entry points for kernel and user space and the CPUstores the entry type (exception, trap, interrupt, syscall) on the entry stack along with the vector number. The entry code has to demultiplex this information, but this removes the vector space restriction. The first hardware implementations will still have the current restricted vector space because lifting this limitation requires further changes to the local APIC. 7) FRED stores the vector number and meta information on stack which allows having more than one NMI vector in future hardware when the required local APIC changes are in place. The series implements the initial FRED support by: - Reworking the existing entry and IDT handling infrastructure to accomodate for the alternative entry mechanism. - Expanding the stack frame to accomodate for the extra 16 bytes FRED requires to store context and meta information - Providing FRED specific C entry points for events which have information pushed to the extended stack frame, e.g. #PF and #DB. - Providing FRED specific C entry points for #NMI and #MCE - Implementing the FRED specific ASM entry points and the C code to demultiplex the events - Providing detection and initialization mechanisms and the necessary tweaks in context switching, GS BASE handling etc. The FRED integration aims for maximum code reuse vs. the existing IDT implementation to the extent possible and the deviation in hot paths like context switching are handled with alternatives to minimalize the impact. The low level entry and exit paths are seperate due to the extended stack frame and the hardware based GS BASE swichting and therefore have no impact on IDT based systems. It has been extensively tested on existing systems and on the FRED simulation and as of now there are know outstanding problems. -----BEGIN PGP SIGNATURE----- iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmXuKPgTHHRnbHhAbGlu dXRyb25peC5kZQAKCRCmGPVMDXSYoWyUEACevJMHU+Ot9zqBPizSWxByM1uunHbp bjQXhaFeskd3mt7k7HU6GsPRSmC3q4lliP1Y9ypfbU0DvYSI2h/PhMWizjhmot2y nIvFpl51r/NsI+JHx1oXcFetz0eGHEqBui/4YQ/swgOCMymYgfqgHhazXTdldV3g KpH9/8W3AeGvw79uzXFH9tjBzTkbvywpam3v0LYNDJWTCuDkilyo8PjhsgRZD4x3 V9f1nLD7nSHZW8XLoktdJJ38bKwI2Lhao91NQ0ErwopekA4/9WphZEKsDpidUSXJ sn1O148oQ8X92IO2OaQje8XC5pLGr5GqQBGPWzRH56P/Vd3+WOwBxaFoU6Drxc5s tIe23ZjkVcpA8EEG7BQBZV1Un/NX7XaCCnMniOt0RauXw+1NaslX7t/tnUAh5F1V TWCH4D0I0oJ0qJ7kNliGn2BP3agYXOVg81xVEUjT6KfHcYU4ImUrwi+BkeNXuXtL Ch5ADnbYAcUjWLFnAmEmaRtfmfNGY5T7PeGFHW2RRkaOJ88v5g14Voo6gPJaDUPn wMQ0nLq1xN4xZWF6ZgfRqAhArvh20k38ZujRku5vXEqnhOugQ76TF2UYiFEwOXbQ 8jcM+yEBLGgBz7tGMwmIAml6kfxaFF1KPpdrtcPxNkGlbE6KTSuIolLx2YGUvlSU 6/O8nwZy49ckmQ== =Ib7w -----END PGP SIGNATURE----- Merge tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 FRED support from Thomas Gleixner: "Support for x86 Fast Return and Event Delivery (FRED). FRED is a replacement for IDT event delivery on x86 and addresses most of the technical nightmares which IDT exposes: 1) Exception cause registers like CR2 need to be manually preserved in nested exception scenarios. 2) Hardware interrupt stack switching is suboptimal for nested exceptions as the interrupt stack mechanism rewinds the stack on each entry which requires a massive effort in the low level entry of #NMI code to handle this. 3) No hardware distinction between entry from kernel or from user which makes establishing kernel context more complex than it needs to be especially for unconditionally nestable exceptions like NMI. 4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a problem when the perf NMI takes a fault when collecting a stack trace. 5) Partial restore of ESP when returning to a 16-bit segment 6) Limitation of the vector space which can cause vector exhaustion on large systems. 7) Inability to differentiate NMI sources FRED addresses these shortcomings by: 1) An extended exception stack frame which the CPU uses to save exception cause registers. This ensures that the meta information for each exception is preserved on stack and avoids the extra complexity of preserving it in software. 2) Hardware interrupt stack switching is non-rewinding if a nested exception uses the currently interrupt stack. 3) The entry points for kernel and user context are separate and GS BASE handling which is required to establish kernel context for per CPU variable access is done in hardware. 4) NMIs are now nesting protected. They are only reenabled on the return from NMI. 5) FRED guarantees full restore of ESP 6) FRED does not put a limitation on the vector space by design because it uses a central entry points for kernel and user space and the CPUstores the entry type (exception, trap, interrupt, syscall) on the entry stack along with the vector number. The entry code has to demultiplex this information, but this removes the vector space restriction. The first hardware implementations will still have the current restricted vector space because lifting this limitation requires further changes to the local APIC. 7) FRED stores the vector number and meta information on stack which allows having more than one NMI vector in future hardware when the required local APIC changes are in place. The series implements the initial FRED support by: - Reworking the existing entry and IDT handling infrastructure to accomodate for the alternative entry mechanism. - Expanding the stack frame to accomodate for the extra 16 bytes FRED requires to store context and meta information - Providing FRED specific C entry points for events which have information pushed to the extended stack frame, e.g. #PF and #DB. - Providing FRED specific C entry points for #NMI and #MCE - Implementing the FRED specific ASM entry points and the C code to demultiplex the events - Providing detection and initialization mechanisms and the necessary tweaks in context switching, GS BASE handling etc. The FRED integration aims for maximum code reuse vs the existing IDT implementation to the extent possible and the deviation in hot paths like context switching are handled with alternatives to minimalize the impact. The low level entry and exit paths are seperate due to the extended stack frame and the hardware based GS BASE swichting and therefore have no impact on IDT based systems. It has been extensively tested on existing systems and on the FRED simulation and as of now there are no outstanding problems" * tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) x86/fred: Fix init_task thread stack pointer initialization MAINTAINERS: Add a maintainer entry for FRED x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly x86/fred: Invoke FRED initialization code to enable FRED x86/fred: Add FRED initialization functions x86/syscall: Split IDT syscall setup code into idt_syscall_init() KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled x86/traps: Add sysvec_install() to install a system interrupt handler x86/fred: FRED entry/exit and dispatch code x86/fred: Add a machine check entry stub for FRED x86/fred: Add a NMI entry stub for FRED x86/fred: Add a debug fault entry stub for FRED x86/idtentry: Incorporate definitions/declarations of the FRED entries x86/fred: Make exc_page_fault() work for FRED x86/fred: Allow single-step trap and NMI when starting a new task x86/fred: No ESPFIX needed when FRED is enabled ...	2024-03-11 16:00:17 -07:00
Pawan Gupta	2a0180129d	KVM/x86: Export RFDS_NO and RFDS_CLEAR to guests ... Mitigation for RFDS requires RFDS_CLEAR capability which is enumerated by MSR_IA32_ARCH_CAPABILITIES bit 27. If the host has it set, export it to guests so that they can deploy the mitigation. RFDS_NO indicates that the system is not vulnerable to RFDS, export it to guests so that they don't deploy the mitigation unnecessarily. When the host is not affected by X86_BUG_RFDS, but has RFDS_NO=0, synthesize RFDS_NO to the guest. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>	2024-03-11 13:13:50 -07:00
Paolo Bonzini	e9a2bba476	KVM Xen and pfncache changes for 6.9: ... - Rip out the half-baked support for using gfn_to_pfn caches to manage pages that are "mapped" into guests via physical addresses. - Add support for using gfn_to_pfn caches with only a host virtual address, i.e. to bypass the "gfn" stage of the cache. The primary use case is overlay pages, where the guest may change the gfn used to reference the overlay page, but the backing hva+pfn remains the same. - Add an ioctl() to allow mapping Xen's shared_info page using an hva instead of a gpa, so that userspace doesn't need to reconfigure and invalidate the cache/mapping if the guest changes the gpa (but userspace keeps the resolved hva the same). - When possible, use a single host TSC value when computing the deadline for Xen timers in order to improve the accuracy of the timer emulation. - Inject pending upcall events when the vCPU software-enables its APIC to fix a bug where an upcall can be lost (and to follow Xen's behavior). - Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen events fails, e.g. if the guest has aliased xAPIC IDs. - Extend gfn_to_pfn_cache's mutex to cover (de)activation (in addition to refresh), and drop a now-redundant acquisition of xen_lock (that was protecting the shared_info cache) to fix a deadlock due to recursively acquiring xen_lock. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEKTobbabEP7vbhhN9OlYIJqCjN/0FAmXrblYACgkQOlYIJqCj N/3K4Q/+KZ8lrnNXvdHNCQdosA5DDXpqUcRzhlTUp82fncpdJ0LqrSMzMots2Eh9 KC0jSPo8EkivF+Epug0+bpQBEaLXzTWhRcS1grePCDz2lBnxoHFSWjvaK2p14KlC LvxCJZjxyfLKHwKHpSndvO9hVFElCY3mvvE9KRcKeQAmrz1cz+DDMKelo1MuV8D+ GfymhYc+UXpY41+6hQdznx+WoGoXKRameo3iGYuBoJjvKOyl4Wxkx9WSXIxxxuqG kHxjiWTR/jF1ITJl6PeMrFcGl3cuGKM/UfTOM6W2h6Wi3mhLpXveoVLnqR1kipIj btSzSVHL7C4WTPwOcyhwPzap+dJmm31c6N0uPScT7r9yhs+q5BDj26vcVcyPZUHo efIwmsnO2eQvuw+f8C6QqWCPaxvw46N0zxzwgc5uA3jvAC93y0l4v+xlAQsC0wzV 0+BwU00cutH/3t3c/WPD5QcmRLH726VoFuTlaDufpoMU7gBVJ8rzjcusxR+5BKT+ GJcAgZxZhEgvnzmTKd4Ec/mt+xZ2Erd+kV3MKCHvDPyj8jqy8FQ4DAWKGBR+h3WR rqAs2k8NPHyh3i1a3FL1opmxEGsRS+Cnc6Bi77cj9DxTr22JkgDJEuFR+Ues1z6/ SpE889kt3w5zTo34+lNxNPlIKmO0ICwwhDL6pxJTWU7iWQnKypU= =GliW -----END PGP SIGNATURE----- Merge tag 'kvm-x86-xen-6.9' of https://github.com/kvm-x86/linux into HEAD KVM Xen and pfncache changes for 6.9: - Rip out the half-baked support for using gfn_to_pfn caches to manage pages that are "mapped" into guests via physical addresses. - Add support for using gfn_to_pfn caches with only a host virtual address, i.e. to bypass the "gfn" stage of the cache. The primary use case is overlay pages, where the guest may change the gfn used to reference the overlay page, but the backing hva+pfn remains the same. - Add an ioctl() to allow mapping Xen's shared_info page using an hva instead of a gpa, so that userspace doesn't need to reconfigure and invalidate the cache/mapping if the guest changes the gpa (but userspace keeps the resolved hva the same). - When possible, use a single host TSC value when computing the deadline for Xen timers in order to improve the accuracy of the timer emulation. - Inject pending upcall events when the vCPU software-enables its APIC to fix a bug where an upcall can be lost (and to follow Xen's behavior). - Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen events fails, e.g. if the guest has aliased xAPIC IDs. - Extend gfn_to_pfn_cache's mutex to cover (de)activation (in addition to refresh), and drop a now-redundant acquisition of xen_lock (that was protecting the shared_info cache) to fix a deadlock due to recursively acquiring xen_lock.	2024-03-11 10:42:55 -04:00
Paolo Bonzini	e9025cdd8c	KVM x86 PMU changes for 6.9: ... - Fix several bugs where KVM speciously prevents the guest from utilizing fixed counters and architectural event encodings based on whether or not guest CPUID reports support for the _architectural_ encoding. - Fix a variety of bugs in KVM's emulation of RDPMC, e.g. for "fast" reads, priority of VMX interception vs #GP, PMC types in architectural PMUs, etc. - Add a selftest to verify KVM correctly emulates RDMPC, counter availability, and a variety of other PMC-related behaviors that depend on guest CPUID, i.e. are difficult to validate via KVM-Unit-Tests. - Zero out PMU metadata on AMD if the virtual PMU is disabled to avoid wasting cycles, e.g. when checking if a PMC event needs to be synthesized when skipping an instruction. - Optimize triggering of emulated events, e.g. for "count instructions" events when skipping an instruction, which yields a ~10% performance improvement in VM-Exit microbenchmarks when a vPMU is exposed to the guest. - Tighten the check for "PMI in guest" to reduce false positives if an NMI arrives in the host while KVM is handling an IRQ VM-Exit. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEKTobbabEP7vbhhN9OlYIJqCjN/0FAmXrUFQACgkQOlYIJqCj N/11dhAAnr9e6mPmXvaH4YKcvOGgTmwIQdi5W4IBzGm27ErEb0Vyskx3UATRhRm+ gZyp3wNgEA9LeifICDNu4ypn7HZcl2VtRql6FYcB8Bcu8OiHfU8PhWL0/qrpY20e zffUj2tDweq2ft9Iks1SQJD0sxFkcXIcSKOffP7pRZJHFTKLltGORXwxzd9HJHPY nc4nERKegK2yH4A4gY6nZ0oV5L3OMUNHx815db5Y+HxXOIjBCjTQiNNd6mUdyX1N C5sIiElXLdvRTSDvirHfA32LqNwnajDGox4QKZkB3wszCxJ3kRd4OCkTEKMYKHxd KoKCJQnAdJFFW9xqbT8nNKXZ+hg2+ZQuoSaBuwKryf7jWi0e6a7jcV0OH+cQSZw7 UNudKhs3r4ambfvnFp2IVZlZREMDB+LAjo2So48Jn/JGCAzqte3XqwVKskn9pS9S qeauXCdOLioZALYtTBl8RM1rEY5mbwQrpPv9CzbeU09qQ/hpXV14W9GmbyeOZcI1 T1cYgEqlLuifRluwT/hxrY321+4noF116gSK1yb07x/sJU8/lhRooEk9V562066E qo6nIvc7Bv9gTGLwo6VReKSPcTT/6t3HwgPsRjqe+evso3EFN9f9hG+uPxtO6TUj pdPm3mkj2KfxDdJLf+Ys16gyGdiwI0ZImIkA0uLdM0zftNsrb4Y= =vayI -----END PGP SIGNATURE----- Merge tag 'kvm-x86-pmu-6.9' of https://github.com/kvm-x86/linux into HEAD KVM x86 PMU changes for 6.9: - Fix several bugs where KVM speciously prevents the guest from utilizing fixed counters and architectural event encodings based on whether or not guest CPUID reports support for the _architectural_ encoding. - Fix a variety of bugs in KVM's emulation of RDPMC, e.g. for "fast" reads, priority of VMX interception vs #GP, PMC types in architectural PMUs, etc. - Add a selftest to verify KVM correctly emulates RDMPC, counter availability, and a variety of other PMC-related behaviors that depend on guest CPUID, i.e. are difficult to validate via KVM-Unit-Tests. - Zero out PMU metadata on AMD if the virtual PMU is disabled to avoid wasting cycles, e.g. when checking if a PMC event needs to be synthesized when skipping an instruction. - Optimize triggering of emulated events, e.g. for "count instructions" events when skipping an instruction, which yields a ~10% performance improvement in VM-Exit microbenchmarks when a vPMU is exposed to the guest. - Tighten the check for "PMI in guest" to reduce false positives if an NMI arrives in the host while KVM is handling an IRQ VM-Exit.	2024-03-11 10:41:09 -04:00
Paolo Bonzini	b00471a552	KVM VMX changes for 6.9: ... - Fix a bug where KVM would report stale/bogus exit qualification information when exiting to userspace due to an unexpected VM-Exit while the CPU was vectoring an exception. - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support. - Clean up the logic for massaging the passthrough MSR bitmaps when userspace changes its MSR filter. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEKTobbabEP7vbhhN9OlYIJqCjN/0FAmXrUh4ACgkQOlYIJqCj N/2CRA//VKa4KE8zgF3xM6Btyt2NegPgmGYVyhmMHTvARyHDIl5nURy++uXseb4f UXQLGcoGS+CIiaMohQFhCOjoNvv/2LR9P72qVV2WjQjFxVGBchybz8bjrqIDSSvY TuiPJApIfZtLryFFcowo8jLEBQv3JKgfgn9r2hBwVDcYP13wSz0Z4AWntHIqBxNa DW75wo7wnBFzy2RfUdtAgucpbmEihqSoKA+YjUT+0GRLBI7rWbFxdEKqe3BIM/7n 4NoJXbOmw7mlhTNumZYsF5sKiyOihBOdtUL1TDgKWjJScgmwG+KCSvrp5Ko4PZpo uyWWcIbskQ+cTO6dHDoIJTVPsCDxo3PgVJKG1T60CV68NavwxXCUGri1n1ZNyYH/ bXxEW7dTGHX0TDSt3dcyVOYdZFHbaIbqpu1EXlrzBm1hnruQ1C1uBQGHZ/X+Yo86 0qdq9SgXJ48tykr8BDruIHMy0Q8jbXxl67oXR0CdRjJGM+H9f+7RefnRN9wPYFhy n6Hl3kbezwCZb+8RO34Hq2CpKzNlKRHlJDhUq1ypd2vXPw8FDq1aQYKih0jAzyJQ yCdUueBJgo8OJtSL4HGEHvgkLHR4/XERgbCOxpSYNbqIjahAwNtbfHryUnJRWRb5 V3QczG/TtGfEpVblbRzn3Atbft4rM5a9Z3+s0siB6C2w8wyPmZg= =oJso -----END PGP SIGNATURE----- Merge tag 'kvm-x86-vmx-6.9' of https://github.com/kvm-x86/linux into HEAD KVM VMX changes for 6.9: - Fix a bug where KVM would report stale/bogus exit qualification information when exiting to userspace due to an unexpected VM-Exit while the CPU was vectoring an exception. - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support. - Clean up the logic for massaging the passthrough MSR bitmaps when userspace changes its MSR filter.	2024-03-11 10:31:29 -04:00
Paolo Bonzini	41ebae2ecd	KVM x86 MMU changes for 6.9: ... - Clean up code related to unprotecting shadow pages when retrying a guest instruction after failed #PF-induced emulation. - Zap TDP MMU roots at 4KiB granularity to minimize the delay in yielding if a reschedule is needed, e.g. if a high priority task needs to run. Because KVM doesn't support yielding in the middle of processing a zapped non-leaf SPTE, zapping at 1GiB granularity can result in multi-millisecond lag when attempting to schedule in a high priority. - Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for read, e.g. to avoid serializing vCPUs when userspace deletes a memslot. - Allocate write-tracking metadata on-demand to avoid the memory overhead when running kernels built with KVMGT support (external write-tracking enabled), but for workloads that don't use nested virtualization (shadow paging) or KVMGT. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEKTobbabEP7vbhhN9OlYIJqCjN/0FAmXrTH4ACgkQOlYIJqCj N/1q3xAAh3wpUDzRfkNkgGUbulhuJmQ72PiaW3NRoMo/3Rowegsdgt1N3/ec+fcJ Awx0KUM8Cju8O2Zqp6NzKwUkddCni8dHmOa55NJQuK2M1OpnE0RjBB94n+AFJZki mm8wKSKNgjlVeJDG87+RLPnbaeEvqYPp22oNKJyAPsimTbxvmhIqtg8qdyujGPXA Jke7LXgtVGav+nEzXiLh86VU/agoBJc/zt+hiuLvamU5Y8so+zReqFbrDtvsgtpV ryvMbDZxcPXKrsBP+B7syqUAbODcmh/wkzOCZ4Tby5yurEaw1rwpZIH0BRKRgGx2 F2JqWayYsCOsrJ4DwQre8RfLMtbEKB2BBWkZlYyblAy0++1LcTP9pSk5YC5lSL71 5Oszql9DKi10Vq5IfR/ehsr6mHXFr3AB7C7QefiXpytGbObQs8/f/OxinxaEajcs ERBgh+rcQ5p3kfdiHzuQjn7y45J7z21CKVhka4iKJtTxypBK4ZvkDOVqHuHppb5O aw6rC5HR1EKhSW4jz7QWrDExtDZ2X5HeYl8TgfHncSSJRc7urKYcSCHhXJsB6BPs iQf0xbHaIOyH9jmoqLZjz0QZmXB9fydQ/zAlFVXZsrNHvomayVjqrpl8UFTMdhuI zll9ynfRRHMUkIi1YubUlmFMgBeqOXGkfBFh8QUH3+YiI7Cwzh4= =SgFo -----END PGP SIGNATURE----- Merge tag 'kvm-x86-mmu-6.9' of https://github.com/kvm-x86/linux into HEAD KVM x86 MMU changes for 6.9: - Clean up code related to unprotecting shadow pages when retrying a guest instruction after failed #PF-induced emulation. - Zap TDP MMU roots at 4KiB granularity to minimize the delay in yielding if a reschedule is needed, e.g. if a high priority task needs to run. Because KVM doesn't support yielding in the middle of processing a zapped non-leaf SPTE, zapping at 1GiB granularity can result in multi-millisecond lag when attempting to schedule in a high priority. - Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for read, e.g. to avoid serializing vCPUs when userspace deletes a memslot. - Allocate write-tracking metadata on-demand to avoid the memory overhead when running kernels built with KVMGT support (external write-tracking enabled), but for workloads that don't use nested virtualization (shadow paging) or KVMGT.	2024-03-11 10:29:22 -04:00
Paolo Bonzini	c9cd0beae9	KVM x86 misc changes for 6.9: ... - Explicitly initialize a variety of on-stack variables in the emulator that triggered KMSAN false positives (though in fairness in KMSAN, it's comically difficult to see that the uninitialized memory is never truly consumed). - Fix the deubgregs ABI for 32-bit KVM, and clean up code related to reading DR6 and DR7. - Rework the "force immediate exit" code so that vendor code ultimately decides how and when to force the exit. This allows VMX to further optimize handling preemption timer exits, and allows SVM to avoid sending a duplicate IPI (SVM also has a need to force an exit). - Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if vCPU creation ultimately failed, and add WARN to guard against similar bugs. - Provide a dedicated arch hook for checking if a different vCPU was in-kernel (for directed yield), and simplify the logic for checking if the currently loaded vCPU is in-kernel. - Misc cleanups and fixes. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEKTobbabEP7vbhhN9OlYIJqCjN/0FAmXrRjQACgkQOlYIJqCj N/2Dzw//b+ptSBAl1kGBRmk/DqsX7J9ZkQYCQOTeh1vXiUM+XRTSQoArN0Oo1roy 3wcEnQ0beVw7jMuzZ8UUuTfU8WUMja/kwltnqXYNHwLnb6yH0I/BIengXWdUdAMc FmgPZ4qJR2IzKYzvDsc3eEQ515O8UHWakyVDnmLBtiakAeBcUTYceHpEEPpzE5y5 ODASTQKM9o/h8R8JwKFTJ8/mrOLNcsu5SycwFdnmubLJCrNWtJWTijA6y1lh6shn hbEJex+ESoC2v8p7IP53u1SGJubVlPajt+RkYJtlEI3WVsevp024eYcF4nb1OjXi qS2Y3W7DQGWvyCBoSzoMY+9nRMgyOOpHYetdiz+9oZOmnjiYWY0ku59U7Gv+Aotj AUbCn4Ry/OpqsuZ7Oo7i3IT8R7uzsTeNNdxhYBn1OQquBEZ0KBYXlZkGfTk9K0t0 Fhka/5Zu6fBlg5J+zCyaXUGmsGWBo/9HxsC5z1JuKo8fatro5qyqYE5KiM01dkqc 6FET6gL+fFprC5c67JGRPdEtk6F9Emb+6oiTTA8/8q8JQQAKiJKk95Nlq7KzPfVS A5RQPTuTJ7acE/5CY4zB1DdxCjqgnonBEA2ULnA/J10Rk8orHJRnGJcEwKEyDrZh HpsxIIqt++i8KffORpCym6zSAVYuQjn1mu7MGth+zuCqhcEpBfc= =GX0O -----END PGP SIGNATURE----- Merge tag 'kvm-x86-misc-6.9' of https://github.com/kvm-x86/linux into HEAD KVM x86 misc changes for 6.9: - Explicitly initialize a variety of on-stack variables in the emulator that triggered KMSAN false positives (though in fairness in KMSAN, it's comically difficult to see that the uninitialized memory is never truly consumed). - Fix the deubgregs ABI for 32-bit KVM, and clean up code related to reading DR6 and DR7. - Rework the "force immediate exit" code so that vendor code ultimately decides how and when to force the exit. This allows VMX to further optimize handling preemption timer exits, and allows SVM to avoid sending a duplicate IPI (SVM also has a need to force an exit). - Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if vCPU creation ultimately failed, and add WARN to guard against similar bugs. - Provide a dedicated arch hook for checking if a different vCPU was in-kernel (for directed yield), and simplify the logic for checking if the currently loaded vCPU is in-kernel. - Misc cleanups and fixes.	2024-03-11 10:24:56 -04:00
Paolo Bonzini	961e2bfcf3	KVM/arm64 updates for 6.9 ... - Infrastructure for building KVM's trap configuration based on the architectural features (or lack thereof) advertised in the VM's ID registers - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to x86's WC) at stage-2, improving the performance of interacting with assigned devices that can tolerate it - Conversion of KVM's representation of LPIs to an xarray, utilized to address serialization some of the serialization on the LPI injection path - Support for _architectural_ VHE-only systems, advertised through the absence of FEAT_E2H0 in the CPU's ID register - Miscellaneous cleanups, fixes, and spelling corrections to KVM and selftests -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQSNXHjWXuzMZutrKNKivnWIJHzdFgUCZepBjgAKCRCivnWIJHzd FnngAP93VxjCkJ+5qSmYpFNG6r0ECVIbLHFQ59nKn0+GgvbPEgEAwt8svdLdW06h njFTpdzvl4Po+aD/V9xHgqVz3kVvZwE= =1FbW -----END PGP SIGNATURE----- Merge tag 'kvmarm-6.9' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 6.9 - Infrastructure for building KVM's trap configuration based on the architectural features (or lack thereof) advertised in the VM's ID registers - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to x86's WC) at stage-2, improving the performance of interacting with assigned devices that can tolerate it - Conversion of KVM's representation of LPIs to an xarray, utilized to address serialization some of the serialization on the LPI injection path - Support for _architectural_ VHE-only systems, advertised through the absence of FEAT_E2H0 in the CPU's ID register - Miscellaneous cleanups, fixes, and spelling corrections to KVM and selftests	2024-03-11 10:02:32 -04:00
Paolo Bonzini	233d0bc4d8	LoongArch KVM changes for v6.9 ... 1. Set reserved bits as zero in CPUCFG. 2. Start SW timer only when vcpu is blocking. 3. Do not restart SW timer when it is expired. 4. Remove unnecessary CSR register saving during enter guest. -----BEGIN PGP SIGNATURE----- iQJKBAABCAA0FiEEzOlt8mkP+tbeiYy5AoYrw/LiJnoFAmXoeWIWHGNoZW5odWFj YWlAa2VybmVsLm9yZwAKCRAChivD8uImehb3D/9C5IrdyU/2f3fEUuuXO0a2ZS1p l2OT+yr7C6/jATokGcd+53CF8MzYawzuAT3tSXYyoqAxRu0HUkvuS1oA/eFM4EwV iIoUC3jnqcsQ5LCPt6yt+Tzgug64Xm5F4btYWIpmXgCJWx/VVG6+z3JarXAfA2it vgVMGgrrfHt68sEsenNFNgiJ5tCCubjR7XFwjM8rsL7AzUDdmXpF7gFyH2Ufgosi a5CxcPPauO1y5ZCGU4JU9QvxnVqW1kt/TRZIGqqGfULtlBSoZbD9zP3OcCQkL+ai SPNxvU5I+BeX6honpmO6aR/F1EphQhRji3ZKxI8UBo4aJD5+FtMG/YOEPI+ZAS0/ JPuWpDqJH46SN3jfKTQay8jXc+mcnOYXJ9Yrixd4UCf66WJit/+BOma/wP638u2j RUzm1kqhNGad6QiDDtSjISM6sg6FozAGc/KhCkWAhV+lHLnfkXtaf3S+GIu5OiWz ETCKlmIGiy0y774+iftlD7RDRGmtrC4cx5ibl7cKKi62Y5vgujCdDofAyYC+D5cW puaIuHOx1hWtPRT9p1WfUL310ED+Qj3N2pDDcJcqdCIiRRZ5l/hxGS7V687a30WV GcegEqh19CjI9KDat4E1ld4jUHJxaFrw3pr2z3SP7cW3IgdngPJL57M0M2jSazaQ 479xZPJ/i4xhJaKACg== =8HOW -----END PGP SIGNATURE----- Merge tag 'loongarch-kvm-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD LoongArch KVM changes for v6.9 * Set reserved bits as zero in CPUCFG. * Start SW timer only when vcpu is blocking. * Do not restart SW timer when it is expired. * Remove unnecessary CSR register saving during enter guest.	2024-03-11 09:56:54 -04:00
Linus Torvalds	137e0ec05a	KVM GUEST_MEMFD fixes for 6.8: ... - Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to avoid creating an inconsistent ABI (KVM_MEM_GUEST_MEMFD is not writable from userspace, so there would be no way to write to a read-only guest_memfd). - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly clear that such VMs are purely for development and testing. - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan is to support confidential VMs with deterministic private memory (SNP and TDX) only in the TDP MMU. - Fix a bug in a GUEST_MEMFD dirty logging test that caused false passes. x86 fixes: - Fix missing marking of a guest page as dirty when emulating an atomic access. - Check for mmu_notifier invalidation events before faulting in the pfn, and before acquiring mmu_lock, to avoid unnecessary work and lock contention with preemptible kernels (including CONFIG_PREEMPT_DYNAMIC in non-preemptible mode). - Disable AMD DebugSwap by default, it breaks VMSA signing and will be re-enabled with a better VM creation API in 6.10. - Do the cache flush of converted pages in svm_register_enc_region() before dropping kvm->lock, to avoid a race with unregistering of the same region and the consequent use-after-free issue. -----BEGIN PGP SIGNATURE----- iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmXskdYUHHBib256aW5p QHJlZGhhdC5jb20ACgkQv/vSX3jHroN1TAf/SUGf4QuYG7nnfgWDR+goFO6Gx7NE pJr3kAwv6d2f+qTlURfGjnX929pgZDLgoTkXTNeZquN6LjgownxMjBIpymVobvAD AKvqJS/ECpryuehXbeqlxJxJn+TrxJ5r4QeNILMHc3AOZoiUqM6xl3zFfXWDNWVo IazwT8P3d8wxiHAxv1eG6OVWHxbcg31068FVKRX3f/bWPbVwROJrPkCopmz2BJvU 6KYdYcn2rkpDTEM3ouDC/6gxJ9vpSY3+nW7Q7dNtGtOH2+BddfSA6I0rphCQWCNs uXOxd5bDrC+KmkiULTPostuvwBgIm1k9wC2kW9A4P2VEf6Ay+ZHEdAOBJQ== =+MT/ -----END PGP SIGNATURE----- Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm Pull kvm fixes from Paolo Bonzini: "KVM GUEST_MEMFD fixes for 6.8: - Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to avoid creating an inconsistent ABI (KVM_MEM_GUEST_MEMFD is not writable from userspace, so there would be no way to write to a read-only guest_memfd). - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly clear that such VMs are purely for development and testing. - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan is to support confidential VMs with deterministic private memory (SNP and TDX) only in the TDP MMU. - Fix a bug in a GUEST_MEMFD dirty logging test that caused false passes. x86 fixes: - Fix missing marking of a guest page as dirty when emulating an atomic access. - Check for mmu_notifier invalidation events before faulting in the pfn, and before acquiring mmu_lock, to avoid unnecessary work and lock contention with preemptible kernels (including CONFIG_PREEMPT_DYNAMIC in non-preemptible mode). - Disable AMD DebugSwap by default, it breaks VMSA signing and will be re-enabled with a better VM creation API in 6.10. - Do the cache flush of converted pages in svm_register_enc_region() before dropping kvm->lock, to avoid a race with unregistering of the same region and the consequent use-after-free issue" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: SEV: disable SEV-ES DebugSwap by default KVM: x86/mmu: Retry fault before acquiring mmu_lock if mapping is changing KVM: SVM: Flush pages under kvm->lock to fix UAF in svm_register_enc_region() KVM: selftests: Add a testcase to verify GUEST_MEMFD and READONLY are exclusive KVM: selftests: Create GUEST_MEMFD for relevant invalid flags testcases KVM: x86/mmu: Restrict KVM_SW_PROTECTED_VM to the TDP MMU KVM: x86: Update KVM_SW_PROTECTED_VM docs to make it clear they're a WIP KVM: Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY KVM: x86: Mark target gfn of emulated atomic instruction as dirty	2024-03-10 09:27:39 -07:00
Paolo Bonzini	7d8942d8e7	KVM GUEST_MEMFD fixes for 6.8: ... - Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to avoid creating ABI that KVM can't sanely support. - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly clear that such VMs are purely a development and testing vehicle, and come with zero guarantees. - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan is to support confidential VMs with deterministic private memory (SNP and TDX) only in the TDP MMU. - Fix a bug in a GUEST_MEMFD negative test that resulted in false passes when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEKTobbabEP7vbhhN9OlYIJqCjN/0FAmXZB/8ACgkQOlYIJqCj N/3XlQ//RIsvqr38k7kELSKhCMyWgF4J57itABrHpMqAZu3gaAo5sETX8AGcHEe5 mxmquxyNQSf4cthhWy1kzxjGCy6+fk+Z0Z7wzfz0Yd5D+FI6vpo3HhkjovLb2gpt kSrHuhJyuj2vkftNvdaz0nHX1QalVyIEnXnR3oqTmxUUsg6lp1x/zr5SP0KBXjo8 ZzJtyFd0fkRXWpA792T7XPRBWrzPV31HYZBLX8sPlYmJATcbIx9rYSThgCN6XuVN bfE6wATsC+mwv5BpCoDFpCKmFcqSqamag9NGe5qE5mOby5DQGYTCRMCQB8YXXBR0 97ppaY9ZJV4nOVjrYJn6IMOSMVNfoG7nTRFfcd0eFP4tlPEgHwGr5BGDaBtQPkrd KcgWJw8nS02eCA2iOE+FtCXvGJwKhTTjQ45w7rU4EcfUk603L5J4GO1ddmjMhPcP upGGcWDK9vCGrSUFTm8pyWp/NKRJPvAQEiQd/BweSk9+isQHTX2RYCQgPAQnwlTS wTg7ZPNSLoUkRYmd6r+TUT32ELJGNc8GLftMnxIwweq6V7AgNMi0HE60eMovuBNO 7DAWWzfBEZmJv+0mNNZPGXczHVv4YvMWysRdKkhztBc3+sO7P3AL1zWIDlm5qwoG LpFeeI3qo3o5ZNaqGzkSop2pUUGNGpWCH46WmP0AG7RpzW/Natw= =M0td -----END PGP SIGNATURE----- Merge tag 'kvm-x86-guest_memfd_fixes-6.8' of https://github.com/kvm-x86/linux into HEAD KVM GUEST_MEMFD fixes for 6.8: - Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to avoid creating ABI that KVM can't sanely support. - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly clear that such VMs are purely a development and testing vehicle, and come with zero guarantees. - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan is to support confidential VMs with deterministic private memory (SNP and TDX) only in the TDP MMU. - Fix a bug in a GUEST_MEMFD negative test that resulted in false passes when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged.	2024-03-09 11:48:35 -05:00
Paolo Bonzini	5abf6dceb0	SEV: disable SEV-ES DebugSwap by default ... The DebugSwap feature of SEV-ES provides a way for confidential guests to use data breakpoints. However, because the status of the DebugSwap feature is recorded in the VMSA, enabling it by default invalidates the attestation signatures. In 6.10 we will introduce a new API to create SEV VMs that will allow enabling DebugSwap based on what the user tells KVM to do. Contextually, we will change the legacy KVM_SEV_ES_INIT API to never enable DebugSwap. For compatibility with kernels that pre-date the introduction of DebugSwap, as well as with those where KVM_SEV_ES_INIT will never enable it, do not enable the feature by default. If anybody wants to use it, for now they can enable the sev_es_debug_swap_enabled module parameter, but this will result in a warning. Fixes: d1f85fbe83 ("KVM: SEV: Enable data breakpoints in SEV-ES") Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>	2024-03-09 11:42:25 -05:00
Paolo Bonzini	39fee313fd	Merge tag 'kvm-x86-guest_memfd_fixes-6.8' of https://github.com/kvm-x86/linux into HEAD ... KVM GUEST_MEMFD fixes for 6.8: - Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to avoid creating ABI that KVM can't sanely support. - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly clear that such VMs are purely a development and testing vehicle, and come with zero guarantees. - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan is to support confidential VMs with deterministic private memory (SNP and TDX) only in the TDP MMU. - Fix a bug in a GUEST_MEMFD negative test that resulted in false passes when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged.	2024-03-09 11:42:17 -05:00
Paolo Bonzini	1b6c146df5	Merge tag 'kvm-x86-fixes-6.8-2' of https://github.com/kvm-x86/linux into HEAD ... KVM x86 fixes for 6.8, round 2: - When emulating an atomic access, mark the gfn as dirty in the memslot to fix a bug where KVM could fail to mark the slot as dirty during live migration, ultimately resulting in guest data corruption due to a dirty page not being re-copied from the source to the target. - Check for mmu_notifier invalidation events before faulting in the pfn, and before acquiring mmu_lock, to avoid unnecessary work and lock contention. Contending mmu_lock is especially problematic on preemptible kernels, as KVM may yield mmu_lock in response to the contention, which severely degrades overall performance due to vCPUs making it difficult for the task that triggered invalidation to make forward progress. Note, due to another kernel bug, this fix isn't limited to preemtible kernels, as any kernel built with CONFIG_PREEMPT_DYNAMIC=y will yield contended rwlocks and spinlocks. https://lore.kernel.org/all/20240110214723.695930-1-seanjc@google.com	2024-03-09 11:42:06 -05:00
Peter Xu	e72c7c2b88	mm/treewide: drop pXd_large() ... They're not used anymore, drop all of them. Link: https://lkml.kernel.org/r/20240305043750.93762-10-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>	2024-03-06 13:04:19 -08:00
Peter Xu	0a845e0f63	mm/treewide: replace pud_large() with pud_leaf() ... pud_large() is always defined as pud_leaf(). Merge their usages. Chose pud_leaf() because pud_leaf() is a global API, while pud_large() is not. Link: https://lkml.kernel.org/r/20240305043750.93762-9-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>	2024-03-06 13:04:19 -08:00
Peter Xu	2f709f7bfd	mm/treewide: replace pmd_large() with pmd_leaf() ... pmd_large() is always defined as pmd_leaf(). Merge their usages. Chose pmd_leaf() because pmd_leaf() is a global API, while pmd_large() is not. Link: https://lkml.kernel.org/r/20240305043750.93762-8-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>	2024-03-06 13:04:19 -08:00
David Woodhouse	7a36d68065	KVM: x86/xen: fix recursive deadlock in timer injection ... The fast-path timer delivery introduced a recursive locking deadlock when userspace configures a timer which has already expired and is delivered immediately. The call to kvm_xen_inject_timer_irqs() can call to kvm_xen_set_evtchn() which may take kvm->arch.xen.xen_lock, which is already held in kvm_xen_vcpu_get_attr(). ============================================ WARNING: possible recursive locking detected 6.8.0-smp--5e10b4d51d77-drs #232 Tainted: G O -------------------------------------------- xen_shinfo_test/250013 is trying to acquire lock: ffff938c9930cc30 (&kvm->arch.xen.xen_lock){+.+.}-{3:3}, at: kvm_xen_set_evtchn+0x74/0x170 [kvm] but task is already holding lock: ffff938c9930cc30 (&kvm->arch.xen.xen_lock){+.+.}-{3:3}, at: kvm_xen_vcpu_get_attr+0x38/0x250 [kvm] Now that the gfn_to_pfn_cache has its own self-sufficient locking, its callers no longer need to ensure serialization, so just stop taking kvm->arch.xen.xen_lock from kvm_xen_set_evtchn(). Fixes: 77c9b9dea4 ("KVM: x86/xen: Use fast path for Xen timer delivery") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org> Link: https://lore.kernel.org/r/20240227115648.3104-6-dwmw2@infradead.org Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-03-04 16:22:39 -08:00
David Woodhouse	66e3cf729b	KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery ... The kvm_xen_inject_vcpu_vector() function has a comment saying "the fast version will always work for physical unicast", justifying its use of kvm_irq_delivery_to_apic_fast() and the WARN_ON_ONCE() when that fails. In fact that assumption isn't true if X2APIC isn't in use by the guest and there is (8-bit x)APIC ID aliasing. A single "unicast" destination APIC ID *may* then be delivered to multiple vCPUs. Remove the warning, and in fact it might as well just call kvm_irq_delivery_to_apic(). Reported-by: Michal Luczaj <mhal@rbox.co> Fixes: fde0451be8 ("KVM: x86/xen: Support per-vCPU event channel upcall via local APIC") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org> Link: https://lore.kernel.org/r/20240227115648.3104-4-dwmw2@infradead.org Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-03-04 16:22:37 -08:00
David Woodhouse	8e62bf2bfa	KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled ... Linux guests since commit b1c3497e60 ("x86/xen: Add support for HVMOP_set_evtchn_upcall_vector") in v6.0 onwards will use the per-vCPU upcall vector when it's advertised in the Xen CPUID leaves. This upcall is injected through the guest's local APIC as an MSI, unlike the older system vector which was merely injected by the hypervisor any time the CPU was able to receive an interrupt and the upcall_pending flags is set in its vcpu_info. Effectively, that makes the per-CPU upcall edge triggered instead of level triggered, which results in the upcall being lost if the MSI is delivered when the local APIC is *disabled*. Xen checks the vcpu_info->evtchn_upcall_pending flag when the local APIC for a vCPU is software enabled (in fact, on any write to the SPIV register which doesn't disable the APIC). Do the same in KVM since KVM doesn't provide a way for userspace to intervene and trap accesses to the SPIV register of a local APIC emulated by KVM. Fixes: fde0451be8 ("KVM: x86/xen: Support per-vCPU event channel upcall via local APIC") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240227115648.3104-3-dwmw2@infradead.org Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-03-04 16:22:36 -08:00
David Woodhouse	451a707813	KVM: x86/xen: improve accuracy of Xen timers ... A test program such as http://david.woodhou.se/timerlat.c confirms user reports that timers are increasingly inaccurate as the lifetime of a guest increases. Reporting the actual delay observed when asking for 100µs of sleep, it starts off OK on a newly-launched guest but gets worse over time, giving incorrect sleep times: root@ip-10-0-193-21:~# ./timerlat -c -n 5 00000000 latency 103243/100000 (3.2430%) 00000001 latency 103243/100000 (3.2430%) 00000002 latency 103242/100000 (3.2420%) 00000003 latency 103245/100000 (3.2450%) 00000004 latency 103245/100000 (3.2450%) The biggest problem is that get_kvmclock_ns() returns inaccurate values when the guest TSC is scaled. The guest sees a TSC value scaled from the host TSC by a mul/shift conversion (hopefully done in hardware). The guest then converts that guest TSC value into nanoseconds using the mul/shift conversion given to it by the KVM pvclock information. But get_kvmclock_ns() performs only a single conversion directly from host TSC to nanoseconds, giving a different result. A test program at http://david.woodhou.se/tsdrift.c demonstrates the cumulative error over a day. It's non-trivial to fix get_kvmclock_ns(), although I'll come back to that. The actual guest hv_clock is per-CPU, and *theoretically* each vCPU could be running at a *different* frequency. But this patch is needed anyway because... The other issue with Xen timers was that the code would snapshot the host CLOCK_MONOTONIC at some point in time, and then... after a few interrupts may have occurred, some preemption perhaps... would also read the guest's kvmclock. Then it would proceed under the false assumption that those two happened at the *same* time. Any time which *actually* elapsed between reading the two clocks was introduced as inaccuracies in the time at which the timer fired. Fix it to use a variant of kvm_get_time_and_clockread(), which reads the host TSC just *once*, then use the returned TSC value to calculate the kvmclock (making sure to do that the way the guest would instead of making the same mistake get_kvmclock_ns() does). Sadly, hrtimers based on CLOCK_MONOTONIC_RAW are not supported, so Xen timers still have to use CLOCK_MONOTONIC. In practice the difference between the two won't matter over the timescales involved, as the *absolute* values don't matter; just the delta. This does mean a new variant of kvm_get_time_and_clockread() is needed; called kvm_get_monotonic_and_clockread() because that's what it does. Fixes: 5363952605 ("KVM: x86/xen: handle PV timers oneshot mode") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org> Link: https://lore.kernel.org/r/20240227115648.3104-2-dwmw2@infradead.org [sean: massage moved comment, tweak if statement formatting] Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-03-04 16:22:32 -08:00
Thomas Gleixner	65efc4dc12	x86/cpu: Provide a declaration for itlb_multihit_kvm_mitigation ... Sparse complains rightfully about the missing declaration which has been placed sloppily into the usage site: bugs.c:2223:6: sparse: warning: symbol 'itlb_multihit_kvm_mitigation' was not declared. Should it be static? Add it to <asm/spec-ctrl.h> where it belongs and remove the one in the KVM code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240304005104.787173239@linutronix.de	2024-03-04 12:09:13 +01:00
Sean Christopherson	259720c37d	KVM: VMX: Combine "check" and "get" APIs for passthrough MSR lookups ... Combine possible_passthrough_msr_slot() and is_valid_passthrough_msr() into a single function, vmx_get_passthrough_msr_slot(), and have the combined helper return the slot on success, using a negative value to indicate "failure". Combining the operations avoids iterating over the array of passthrough MSRs twice for relevant MSRs. Suggested-by: Dongli Zhang <dongli.zhang@oracle.com> Reviewed-by: Dongli Zhang <dongli.zhang@oracle.com> Link: https://lore.kernel.org/r/20240223202104.3330974-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-27 12:29:46 -08:00
Andrei Vagin	a364c014a2	kvm/x86: allocate the write-tracking metadata on-demand ... The write-track is used externally only by the gpu/drm/i915 driver. Currently, it is always enabled, if a kernel has been compiled with this driver. Enabling the write-track mechanism adds a two-byte overhead per page across all memory slots. It isn't significant for regular VMs. However in gVisor, where the entire process virtual address space is mapped into the VM, even with a 39-bit address space, the overhead amounts to 256MB. Rework the write-tracking mechanism to enable it on-demand in kvm_page_track_register_notifier. Here is Sean's comment about the locking scheme: The only potential hiccup would be if taking slots_arch_lock would deadlock, but it should be impossible for slots_arch_lock to be taken in any other path that involves VFIO and/or KVMGT *and* can be coincident. Except for kvm_arch_destroy_vm() (which deletes KVM's internal memslots), slots_arch_lock is taken only through KVM ioctls(), and the caller of kvm_page_track_register_notifier() *must* hold a reference to the VM. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Andrei Vagin <avagin@google.com> Link: https://lore.kernel.org/r/20240213192340.2023366-1-avagin@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-27 11:49:54 -08:00
Dongli Zhang	bab22040d7	KVM: VMX: return early if msr_bitmap is not supported ... The vmx_msr_filter_changed() may directly/indirectly calls only vmx_enable_intercept_for_msr() or vmx_disable_intercept_for_msr(). Those two functions may exit immediately if !cpu_has_vmx_msr_bitmap(). vmx_msr_filter_changed() -> vmx_disable_intercept_for_msr() -> pt_update_intercept_for_msr() -> vmx_set_intercept_for_msr() -> vmx_enable_intercept_for_msr() -> vmx_disable_intercept_for_msr() Therefore, we exit early if !cpu_has_vmx_msr_bitmap(). Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Link: https://lore.kernel.org/r/20240223202104.3330974-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-27 09:36:48 -08:00
Dongli Zhang	8e24eeedfd	KVM: VMX: fix comment to add LBR to passthrough MSRs ... According to the is_valid_passthrough_msr(), the LBR MSRs are also passthrough MSRs, since the commit 1b5ac3226a ("KVM: vmx/pmu: Pass-through LBR msrs when the guest LBR event is ACTIVE"). Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Link: https://lore.kernel.org/r/20240223202104.3330974-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-27 09:36:48 -08:00
Like Xu	812d432373	KVM: x86/pmu: Explicitly check NMI from guest to reducee false positives ... Explicitly check that the source of external interrupt is indeed an NMI in kvm_arch_pmi_in_guest(), which reduces perf-kvm false positive samples (host samples labelled as guest samples) generated by perf/core NMI mode if an NMI arrives after VM-Exit, but before kvm_after_interrupt(): # test: perf-record + cpu-cycles:HP (which collects host-only precise samples) # Symbol Overhead sys usr guest sys guest usr # ....................................... ........ ........ ........ ......... ......... # # Before: [g] entry_SYSCALL_64 24.63% 0.00% 0.00% 24.63% 0.00% [g] syscall_return_via_sysret 23.23% 0.00% 0.00% 23.23% 0.00% [g] files_lookup_fd_raw 6.35% 0.00% 0.00% 6.35% 0.00% # After: [k] perf_adjust_freq_unthr_context 57.23% 57.23% 0.00% 0.00% 0.00% [k] __vmx_vcpu_run 4.09% 4.09% 0.00% 0.00% 0.00% [k] vmx_update_host_rsp 3.17% 3.17% 0.00% 0.00% 0.00% In the above case, perf records the samples labelled '[g]', the RIPs behind the weird samples are actually being queried by perf_instruction_pointer() after determining whether it's in GUEST state or not, and here's the issue: If VM-Exit is caused by a non-NMI interrupt (such as hrtimer_interrupt) and at least one PMU counter is enabled on host, the kvm_arch_pmi_in_guest() will remain true (KVM_HANDLING_IRQ is set) until kvm_before_interrupt(). During this window, if a PMI occurs on host (since the KVM instructions on host are being executed), the control flow, with the help of the host NMI context, will be transferred to perf/core to generate performance samples, thus perf_instruction_pointer() and perf_guest_get_ip() is called. Since kvm_arch_pmi_in_guest() only checks if there is an interrupt, it may cause perf/core to mistakenly assume that the source RIP of the host NMI belongs to the guest world and use perf_guest_get_ip() to get the RIP of a vCPU that has already exited by a non-NMI interrupt. Error samples are recorded and presented to the end-user via perf-report. Such false positive samples could be eliminated by explicitly determining if the exit reason is KVM_HANDLING_NMI. Note that when VM-exit is indeed triggered by PMI and before HANDLING_NMI is cleared, it's also still possible that another PMI is generated on host. Also for perf/core timer mode, the false positives are still possible since those non-NMI sources of interrupts are not always being used by perf/core. For events that are host-only, perf/core can and should eliminate false positives by checking event->attr.exclude_guest, i.e. events that are configured to exclude KVM guests should never fire in the guest. Events that are configured to count host and guest are trickier, perhaps impossible to handle with 100% accuracy? And regardless of what accuracy is provided by perf/core, improving KVM's accuracy is cheap and easy, with no real downsides. Fixes: dd60d21706 ("KVM: x86: Fix perf timer mode IP reporting") Signed-off-by: Like Xu <likexu@tencent.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Link: https://lore.kernel.org/r/20231206032054.55070-1-likexu@tencent.com [sean: massage changelog, squash !!in_nmi() fixup from Like] Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-26 15:57:22 -08:00
Oliver Upton	284851ee5c	KVM: Get rid of return value from kvm_arch_create_vm_debugfs() ... The general expectation with debugfs is that any initialization failure is nonfatal. Nevertheless, kvm_arch_create_vm_debugfs() allows implementations to return an error and kvm_create_vm_debugfs() allows that to fail VM creation. Change to a void return to discourage architectures from making debugfs failures fatal for the VM. Seems like everyone already had the right idea, as all implementations already return 0 unconditionally. Acked-by: Marc Zyngier <maz@kernel.org> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20240216155941.2029458-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>	2024-02-23 21:44:58 +00:00
Sean Christopherson	d02c357e5b	KVM: x86/mmu: Retry fault before acquiring mmu_lock if mapping is changing ... Retry page faults without acquiring mmu_lock, and without even faulting the page into the primary MMU, if the resolved gfn is covered by an active invalidation. Contending for mmu_lock is especially problematic on preemptible kernels as the mmu_notifier invalidation task will yield mmu_lock (see rwlock_needbreak()), delay the in-progress invalidation, and ultimately increase the latency of resolving the page fault. And in the worst case scenario, yielding will be accompanied by a remote TLB flush, e.g. if the invalidation covers a large range of memory and vCPUs are accessing addresses that were already zapped. Faulting the page into the primary MMU is similarly problematic, as doing so may acquire locks that need to be taken for the invalidation to complete (the primary MMU has finer grained locks than KVM's MMU), and/or may cause unnecessary churn (getting/putting pages, marking them accessed, etc). Alternatively, the yielding issue could be mitigated by teaching KVM's MMU iterators to perform more work before yielding, but that wouldn't solve the lock contention and would negatively affect scenarios where a vCPU is trying to fault in an address that is NOT covered by the in-progress invalidation. Add a dedicated lockess version of the range-based retry check to avoid false positives on the sanity check on start+end WARN, and so that it's super obvious that checking for a racing invalidation without holding mmu_lock is unsafe (though obviously useful). Wrap mmu_invalidate_in_progress in READ_ONCE() to ensure that pre-checking invalidation in a loop won't put KVM into an infinite loop, e.g. due to caching the in-progress flag and never seeing it go to '0'. Force a load of mmu_invalidate_seq as well, even though it isn't strictly necessary to avoid an infinite loop, as doing so improves the probability that KVM will detect an invalidation that already completed before acquiring mmu_lock and bailing anyways. Do the pre-check even for non-preemptible kernels, as waiting to detect the invalidation until mmu_lock is held guarantees the vCPU will observe the worst case latency in terms of handling the fault, and can generate even more mmu_lock contention. E.g. the vCPU will acquire mmu_lock, detect retry, drop mmu_lock, re-enter the guest, retake the fault, and eventually re-acquire mmu_lock. This behavior is also why there are no new starvation issues due to losing the fairness guarantees provided by rwlocks: if the vCPU needs to retry, it _must_ drop mmu_lock, i.e. waiting on mmu_lock doesn't guarantee forward progress in the face of _another_ mmu_notifier invalidation event. Note, adding READ_ONCE() isn't entirely free, e.g. on x86, the READ_ONCE() may generate a load into a register instead of doing a direct comparison (MOV+TEST+Jcc instead of CMP+Jcc), but practically speaking the added cost is a few bytes of code and maaaaybe a cycle or three. Reported-by: Yan Zhao <yan.y.zhao@intel.com> Closes: https://lore.kernel.org/all/ZNnPF4W26ZbAyGto@yzhao56-desk.sh.intel.com Reported-by: Friedrich Weber <f.weber@proxmox.com> Cc: Kai Huang <kai.huang@intel.com> Cc: Yan Zhao <yan.y.zhao@intel.com> Cc: Yuan Yao <yuan.yao@linux.intel.com> Cc: Xu Yilun <yilun.xu@linux.intel.com> Acked-by: Kai Huang <kai.huang@intel.com> Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/r/20240222012640.2820927-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-23 10:14:34 -08:00
Masahiro Yamada	bf48d9b756	kbuild: change tool coverage variables to take the path relative to $(obj) ... Commit 54b8ae66ae ("kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)") changed the syntax of per-file compiler flags. The situation is the same for the following variables: OBJECT_FILES_NON_STANDARD_<basetarget>.o GCOV_PROFILE_<basetarget>.o KASAN_SANITIZE_<basetarget>.o KMSAN_SANITIZE_<basetarget>.o KMSAN_ENABLE_CHECKS_<basetarget>.o UBSAN_SANITIZE_<basetarget>.o KCOV_INSTRUMENT_<basetarget>.o KCSAN_SANITIZE_<basetarget>.o KCSAN_INSTRUMENT_BARRIERS_<basetarget>.o The <basetarget> is the filename of the target with its directory and suffix stripped. This syntax comes into a trouble when two files with the same basename appear in one Makefile, for example: obj-y += dir1/foo.o obj-y += dir2/foo.o OBJECT_FILES_NON_STANDARD_foo.o := y OBJECT_FILES_NON_STANDARD_foo.o is applied to both dir1/foo.o and dir2/foo.o. This syntax is not flexbile enough to handle cases where one of them is a standard object, but the other is not. It is more sensible to use the relative path to the Makefile, like this: obj-y += dir1/foo.o OBJECT_FILES_NON_STANDARD_dir1/foo.o := y obj-y += dir2/foo.o OBJECT_FILES_NON_STANDARD_dir2/foo.o := y To maintain the current behavior, I made adjustments to the following two Makefiles: - arch/x86/entry/vdso/Makefile, which compiles vclock_gettime.o, vgetcpu.o, and their vdso32 variants. - arch/x86/kvm/Makefile, which compiles vmx/vmenter.o and svm/vmenter.o Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> Acked-by: Sean Christopherson <seanjc@google.com>	2024-02-23 21:06:21 +09:00
Sean Christopherson	5ef1d8c1dd	KVM: SVM: Flush pages under kvm->lock to fix UAF in svm_register_enc_region() ... Do the cache flush of converted pages in svm_register_enc_region() before dropping kvm->lock to fix use-after-free issues where region and/or its array of pages could be freed by a different task, e.g. if userspace has __unregister_enc_region_locked() already queued up for the region. Note, the "obvious" alternative of using local variables doesn't fully resolve the bug, as region->pages is also dynamically allocated. I.e. the region structure itself would be fine, but region->pages could be freed. Flushing multiple pages under kvm->lock is unfortunate, but the entire flow is a rare slow path, and the manual flush is only needed on CPUs that lack coherency for encrypted memory. Fixes: 19a23da539 ("Fix unsynchronized access to sev members through svm_register_enc_region") Reported-by: Gabe Kirkpatrick <gkirkpatrick@google.com> Cc: Josh Eads <josheads@google.com> Cc: Peter Gonda <pgonda@google.com> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20240217013430.2079561-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>	2024-02-23 03:55:59 -05:00
Sean Christopherson	a1176ef5c9	KVM: x86/mmu: Restrict KVM_SW_PROTECTED_VM to the TDP MMU ... Advertise and support software-protected VMs if and only if the TDP MMU is enabled, i.e. disallow KVM_SW_PROTECTED_VM if TDP is enabled for KVM's legacy/shadow MMU. TDP support for the shadow MMU is maintenance-only, e.g. support for TDX and SNP will also be restricted to the TDP MMU. Fixes: 89ea60c2c7 ("KVM: x86: Add support for "protected VMs" that can utilize private memory") Link: https://lore.kernel.org/r/20240222190612.2942589-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 17:07:06 -08:00
Sean Christopherson	422692098c	KVM: x86: Update KVM_SW_PROTECTED_VM docs to make it clear they're a WIP ... Rewrite the help message for KVM_SW_PROTECTED_VM to make it clear that software-protected VMs are a development and testing vehicle for guest_memfd(), and that attempting to use KVM_SW_PROTECTED_VM for anything remotely resembling a "real" VM will fail. E.g. any memory accesses from KVM will incorrectly access shared memory, nested TDP is wildly broken, and so on and so forth. Update KVM's API documentation with similar warnings to discourage anyone from attempting to run anything but selftests with KVM_X86_SW_PROTECTED_VM. Fixes: 89ea60c2c7 ("KVM: x86: Add support for "protected VMs" that can utilize private memory") Link: https://lore.kernel.org/r/20240222190612.2942589-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 17:07:06 -08:00
Sean Christopherson	576a15de8d	KVM: x86/mmu: Free TDP MMU roots while holding mmy_lock for read ... Free TDP MMU roots from vCPU context while holding mmu_lock for read, it is completely legal to invoke kvm_tdp_mmu_put_root() as a reader. This eliminates the last mmu_lock writer in the TDP MMU's "fast zap" path after requesting vCPUs to reload roots, i.e. allows KVM to zap invalidated roots, free obsolete roots, and allocate new roots in parallel. On large VMs, e.g. 100+ vCPUs, allowing the bulk of the "fast zap" operation to run in parallel with freeing and allocating roots reduces the worst case latency for a vCPU to reload a root from 2-3ms to <100us. Link: https://lore.kernel.org/r/20240111020048.844847-9-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	dab285e4ec	KVM: x86/mmu: Alloc TDP MMU roots while holding mmu_lock for read ... Allocate TDP MMU roots while holding mmu_lock for read, and instead use tdp_mmu_pages_lock to guard against duplicate roots. This allows KVM to create new roots without forcing kvm_tdp_mmu_zap_invalidated_roots() to yield, e.g. allows vCPUs to load new roots after memslot deletion without forcing the zap thread to detect contention and yield (or complete if the kernel isn't preemptible). Note, creating a new TDP MMU root as an mmu_lock reader is safe for two reasons: (1) paths that must guarantee all roots/SPTEs are *visited* take mmu_lock for write and so are still mutually exclusive, e.g. mmu_notifier invalidations, and (2) paths that require all roots/SPTEs to *observe* some given state without holding mmu_lock for write must ensure freshness through some other means, e.g. toggling dirty logging must first wait for SRCU readers to recognize the memslot flags change before processing existing roots/SPTEs. Link: https://lore.kernel.org/r/20240111020048.844847-8-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	f5238c2a60	KVM: x86/mmu: Check for usable TDP MMU root while holding mmu_lock for read ... When allocating a new TDP MMU root, check for a usable root while holding mmu_lock for read and only acquire mmu_lock for write if a new root needs to be created. There is no need to serialize other MMU operations if a vCPU is simply grabbing a reference to an existing root, holding mmu_lock for write is "necessary" (spoiler alert, it's not strictly necessary) only to ensure KVM doesn't end up with duplicate roots. Allowing vCPUs to get "new" roots in parallel is beneficial to VM boot and to setups that frequently delete memslots, i.e. which force all vCPUs to reload all roots. Link: https://lore.kernel.org/r/20240111020048.844847-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	d746182337	KVM: x86/mmu: Skip invalid TDP MMU roots when write-protecting SPTEs ... When write-protecting SPTEs, don't process invalid roots as invalid roots are unreachable, i.e. can't be used to access guest memory and thus don't need to be write-protected. Note, this is *almost* a nop for kvm_tdp_mmu_clear_dirty_pt_masked(), which is called under slots_lock, i.e. is mutually exclusive with kvm_mmu_zap_all_fast(). But it's possible for something other than the "fast zap" thread to grab a reference to an invalid root and thus keep a root alive (but completely empty) after kvm_mmu_zap_all_fast() completes. The kvm_tdp_mmu_write_protect_gfn() case is more interesting as KVM write- protects SPTEs for reasons other than dirty logging, e.g. if a KVM creates a SPTE for a nested VM while a fast zap is in-progress. Add another TDP MMU iterator to visit only valid roots, and opportunistically convert kvm_tdp_mmu_get_vcpu_root_hpa() to said iterator. Link: https://lore.kernel.org/r/20240111020048.844847-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	99b85fda91	KVM: x86/mmu: Skip invalid roots when zapping leaf SPTEs for GFN range ... When zapping a GFN in response to an APICv or MTRR change, don't zap SPTEs for invalid roots as KVM only needs to ensure the guest can't use stale mappings for the GFN. Unlike kvm_tdp_mmu_unmap_gfn_range(), which must zap "unreachable" SPTEs to ensure KVM doesn't mark a page accessed/dirty, kvm_tdp_mmu_zap_leafs() isn't used (and isn't intended to be used) to handle freeing of host memory. Link: https://lore.kernel.org/r/20240111020048.844847-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	6577f1efdf	KVM: x86/mmu: Allow passing '-1' for "all" as_id for TDP MMU iterators ... Modify for_each_tdp_mmu_root() and __for_each_tdp_mmu_root_yield_safe() to accept -1 for _as_id to mean "process all memslot address spaces". That way code that wants to process both SMM and !SMM doesn't need to iterate over roots twice (and likely copy+paste code in the process). Deliberately don't cast _as_id to an "int", just in case not casting helps the compiler elide the "_as_id >=0" check when being passed an unsigned value, e.g. from a memslot. No functional change intended. Link: https://lore.kernel.org/r/20240111020048.844847-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	fcdffe97f8	KVM: x86/mmu: Don't do TLB flush when zappings SPTEs in invalid roots ... Don't force a TLB flush when zapping SPTEs in invalid roots as vCPUs can't be actively using invalid roots (zapping SPTEs in invalid roots is necessary only to ensure KVM doesn't mark a page accessed/dirty after it is freed by the primary MMU). Link: https://lore.kernel.org/r/20240111020048.844847-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	8ca983631f	KVM: x86/mmu: Zap invalidated TDP MMU roots at 4KiB granularity ... Zap invalidated TDP MMU roots at maximum granularity, i.e. with more frequent conditional resched checkpoints, in order to avoid running for an extended duration (milliseconds, or worse) without honoring a reschedule request. And for kernels running with full or real-time preempt models, zapping at 4KiB granularity also provides significantly reduced latency for other tasks that are contending for mmu_lock (which isn't necessarily an overall win for KVM, but KVM should do its best to honor the kernel's preemption model). To keep KVM's assertion that zapping at 1GiB granularity is functionally ok, which is the main reason 1GiB was selected in the past, skip straight to zapping at 1GiB if KVM is configured to prove the MMU. Zapping roots is far more common than a vCPU replacing a 1GiB page table with a hugepage, e.g. generally happens multiple times during boot, and so keeping the test coverage provided by root zaps is desirable, just not for production. Cc: David Matlack <dmatlack@google.com> Cc: Pattara Teerapong <pteerapong@google.com> Link: https://lore.kernel.org/r/20240111020048.844847-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:28:45 -08:00
Sean Christopherson	322d79f1db	KVM: x86: Clean up directed yield API for "has pending interrupt" ... Directly return the boolean result of whether or not a vCPU has a pending interrupt instead of effectively doing: if (true) return true; return false; Reviewed-by: Yuan Yao <yuan.yao@intel.com> Link: https://lore.kernel.org/r/20240110003938.490206-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2024-02-22 16:27:40 -08:00