QAT devices on Intel Sapphire Rapids and Emerald Rapids have a defect in
address translation service (ATS). These devices may inadvertently issue
ATS invalidation completion before posted writes initiated with
translated address that utilized translations matching the invalidation
address range, violating the invalidation completion ordering.
This patch adds an extra device TLB invalidation for the affected devices,
it is needed to ensure no more posted writes with translated address
following the invalidation completion. Therefore, the ordering is
preserved and data-corruption is prevented.
Device TLBs are invalidated under the following six conditions:
1. Device driver does DMA API unmap IOVA
2. Device driver unbind a PASID from a process, sva_unbind_device()
3. PASID is torn down, after PASID cache is flushed. e.g. process
exit_mmap() due to crash
4. Under SVA usage, called by mmu_notifier.invalidate_range() where
VM has to free pages that were unmapped
5. userspace driver unmaps a DMA buffer
6. Cache invalidation in vSVA usage (upcoming)
For #1 and #2, device drivers are responsible for stopping DMA traffic
before unmap/unbind. For #3, iommu driver gets mmu_notifier to
invalidate TLB the same way as normal user unmap which will do an extra
invalidation. The dTLB invalidation after PASID cache flush does not
need an extra invalidation.
Therefore, we only need to deal with #4 and #5 in this patch. #1 is also
covered by this patch due to common code path with #5.
Tested-by: Yuzhang Luo <yuzhang.luo@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Link: https://lore.kernel.org/r/20221130062449.1360063-1-jacob.jun.pan@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
SRS cap is the hardware cap telling if the hardware IOMMU can support
requests seeking supervisor privilege or not. SRE bit in scalable-mode
PASID table entry is treated as Reserved(0) for implementation not
supporting SRS cap.
Checking SRS cap before setting SRE bit can avoid the non-recoverable
fault of "Non-zero reserved field set in PASID Table Entry" caused by
setting SRE bit while there is no SRS cap support. The fault messages
look like below:
DMAR: DRHD: handling fault status reg 2
DMAR: [DMA Read NO_PASID] Request device [00:0d.0] fault addr 0x1154e1000
[fault reason 0x5a]
SM: Non-zero reserved field set in PASID Table Entry
Fixes: 6f7db75e1c ("iommu/vt-d: Add second level page table interface")
Cc: stable@vger.kernel.org
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Link: https://lore.kernel.org/r/20221115070346.1112273-1-tina.zhang@intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20221116051544.26540-3-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The A/D bits are preseted for IOVA over first level(FL) usage for both
kernel DMA (i.e, domain typs is IOMMU_DOMAIN_DMA) and user space DMA
usage (i.e., domain type is IOMMU_DOMAIN_UNMANAGED).
Presetting A bit in FL requires to preset the bit in every related paging
entries, including the non-leaf ones. Otherwise, hardware may treat this
as an error. For example, in a case of ECAP_REG.SMPWC==0, DMA faults might
occur with below DMAR fault messages (wrapped for line length) dumped.
DMAR: DRHD: handling fault status reg 2
DMAR: [DMA Read NO_PASID] Request device [aa:00.0] fault addr 0x10c3a6000
[fault reason 0x90]
SM: A/D bit update needed in first-level entry when set up in no snoop
Fixes: 289b3b005c ("iommu/vt-d: Preset A/D bits for user space DMA usage")
Cc: stable@vger.kernel.org
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Link: https://lore.kernel.org/r/20221113010324.1094483-1-tina.zhang@intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20221116051544.26540-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
A splat from kmem_cache_destroy() was seen with a kernel prior to
commit ee2653bbe8 ("iommu/vt-d: Remove domain and devinfo mempool")
when there was a failure in init_dmars(), because the iommu_domain
cache still had objects. While the mempool code is now gone, there
still is a leak of the si_domain memory if init_dmars() fails. So
clean up si_domain in the init_dmars() error path.
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Will Deacon <will@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Fixes: 86080ccc22 ("iommu/vt-d: Allocate si_domain in init_dmars()")
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20221010144842.308890-1-jsnitsel@redhat.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Commit 5f64ce5411 ("iommu/vt-d: Duplicate iommu_resv_region objects
per device list") converted rcu_lock in get_resv_regions to
dmar_global_lock to allow sleeping in iommu_alloc_resv_region(). This
introduced possible recursive locking if get_resv_regions is called from
within a section where intel_iommu_init() already holds dmar_global_lock.
Especially, after commit 57365a04c9 ("iommu: Move bus setup to IOMMU
device registration"), below lockdep splats could always be seen.
============================================
WARNING: possible recursive locking detected
6.0.0-rc4+ #325 Tainted: G I
--------------------------------------------
swapper/0/1 is trying to acquire lock:
ffffffffa8a18c90 (dmar_global_lock){++++}-{3:3}, at:
intel_iommu_get_resv_regions+0x25/0x270
but task is already holding lock:
ffffffffa8a18c90 (dmar_global_lock){++++}-{3:3}, at:
intel_iommu_init+0x36d/0x6ea
...
Call Trace:
<TASK>
dump_stack_lvl+0x48/0x5f
__lock_acquire.cold.73+0xad/0x2bb
lock_acquire+0xc2/0x2e0
? intel_iommu_get_resv_regions+0x25/0x270
? lock_is_held_type+0x9d/0x110
down_read+0x42/0x150
? intel_iommu_get_resv_regions+0x25/0x270
intel_iommu_get_resv_regions+0x25/0x270
iommu_create_device_direct_mappings.isra.28+0x8d/0x1c0
? iommu_get_dma_cookie+0x6d/0x90
bus_iommu_probe+0x19f/0x2e0
iommu_device_register+0xd4/0x130
intel_iommu_init+0x3e1/0x6ea
? iommu_setup+0x289/0x289
? rdinit_setup+0x34/0x34
pci_iommu_init+0x12/0x3a
do_one_initcall+0x65/0x320
? rdinit_setup+0x34/0x34
? rcu_read_lock_sched_held+0x5a/0x80
kernel_init_freeable+0x28a/0x2f3
? rest_init+0x1b0/0x1b0
kernel_init+0x1a/0x130
ret_from_fork+0x1f/0x30
</TASK>
This rolls back dmar_global_lock to rcu_lock in get_resv_regions to avoid
the lockdep splat.
Fixes: 57365a04c9 ("iommu: Move bus setup to IOMMU device registration")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20220927053109.4053662-3-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add gfp parameter to iommu_alloc_resv_region() for the callers to specify
the memory allocation behavior. Thus iommu_alloc_resv_region() could also
be available in critical contexts.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20220927053109.4053662-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Including:
- Removal of the bus_set_iommu() interface which became
unnecesary because of IOMMU per-device probing
- Make the dma-iommu.h header private
- Intel VT-d changes from Lu Baolu:
- Decouple PASID and PRI from SVA
- Add ESRTPS & ESIRTPS capability check
- Cleanups
- Apple DART support for the M1 Pro/MAX SOCs
- Support for AMD IOMMUv2 page-tables for the DMA-API layer. The
v2 page-tables are compatible with the x86 CPU page-tables.
Using them for DMA-API prepares support for hardware-assisted
IOMMU virtualization
- Support for MT6795 Helio X10 M4Us in the Mediatek IOMMU driver
- Some smaller fixes and cleanups
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Merge tag 'iommu-updates-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel:
- remove the bus_set_iommu() interface which became unnecesary because
of IOMMU per-device probing
- make the dma-iommu.h header private
- Intel VT-d changes from Lu Baolu:
- Decouple PASID and PRI from SVA
- Add ESRTPS & ESIRTPS capability check
- Cleanups
- Apple DART support for the M1 Pro/MAX SOCs
- support for AMD IOMMUv2 page-tables for the DMA-API layer.
The v2 page-tables are compatible with the x86 CPU page-tables. Using
them for DMA-API prepares support for hardware-assisted IOMMU
virtualization
- support for MT6795 Helio X10 M4Us in the Mediatek IOMMU driver
- some smaller fixes and cleanups
* tag 'iommu-updates-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (59 commits)
iommu/vt-d: Avoid unnecessary global DMA cache invalidation
iommu/vt-d: Avoid unnecessary global IRTE cache invalidation
iommu/vt-d: Rename cap_5lp_support to cap_fl5lp_support
iommu/vt-d: Remove pasid_set_eafe()
iommu/vt-d: Decouple PASID & PRI enabling from SVA
iommu/vt-d: Remove unnecessary SVA data accesses in page fault path
dt-bindings: iommu: arm,smmu-v3: Relax order of interrupt names
iommu: dart: Support t6000 variant
iommu/io-pgtable-dart: Add DART PTE support for t6000
iommu/io-pgtable: Add DART subpage protection support
iommu/io-pgtable: Move Apple DART support to its own file
iommu/mediatek: Add support for MT6795 Helio X10 M4Us
iommu/mediatek: Introduce new flag TF_PORT_TO_ADDR_MT8173
dt-bindings: mediatek: Add bindings for MT6795 M4U
iommu/iova: Fix module config properly
iommu/amd: Fix sparse warning
iommu/amd: Remove outdated comment
iommu/amd: Free domain ID after domain_flush_pages
iommu/amd: Free domain id in error path
iommu/virtio: Fix compile error with viommu_capable()
...
Here is the large set of char/misc and other small driver subsystem
changes for 6.1-rc1. Loads of different things in here:
- IIO driver updates, additions, and changes. Probably the largest
part of the diffstat
- habanalabs driver update with support for new hardware and features,
the second largest part of the diff.
- fpga subsystem driver updates and additions
- mhi subsystem updates
- Coresight driver updates
- gnss subsystem updates
- extcon driver updates
- icc subsystem updates
- fsi subsystem updates
- nvmem subsystem and driver updates
- misc driver updates
- speakup driver additions for new features
- lots of tiny driver updates and cleanups
All of these have been in the linux-next tree for a while with no
reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc and other driver updates from Greg KH:
"Here is the large set of char/misc and other small driver subsystem
changes for 6.1-rc1. Loads of different things in here:
- IIO driver updates, additions, and changes. Probably the largest
part of the diffstat
- habanalabs driver update with support for new hardware and
features, the second largest part of the diff.
- fpga subsystem driver updates and additions
- mhi subsystem updates
- Coresight driver updates
- gnss subsystem updates
- extcon driver updates
- icc subsystem updates
- fsi subsystem updates
- nvmem subsystem and driver updates
- misc driver updates
- speakup driver additions for new features
- lots of tiny driver updates and cleanups
All of these have been in the linux-next tree for a while with no
reported issues"
* tag 'char-misc-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (411 commits)
w1: Split memcpy() of struct cn_msg flexible array
spmi: pmic-arb: increase SPMI transaction timeout delay
spmi: pmic-arb: block access for invalid PMIC arbiter v5 SPMI writes
spmi: pmic-arb: correct duplicate APID to PPID mapping logic
spmi: pmic-arb: add support to dispatch interrupt based on IRQ status
spmi: pmic-arb: check apid against limits before calling irq handler
spmi: pmic-arb: do not ack and clear peripheral interrupts in cleanup_irq
spmi: pmic-arb: handle spurious interrupt
spmi: pmic-arb: add a print in cleanup_irq
drivers: spmi: Directly use ida_alloc()/free()
MAINTAINERS: add TI ECAP driver info
counter: ti-ecap-capture: capture driver support for ECAP
Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows items
dt-bindings: counter: add ti,am62-ecap-capture.yaml
counter: Introduce the COUNTER_COMP_ARRAY component type
counter: Consolidate Counter extension sysfs attribute creation
counter: Introduce the Count capture component
counter: 104-quad-8: Add Signal polarity component
counter: Introduce the Signal polarity component
counter: interrupt-cnt: Implement watch_validate callback
...
- arm64 perf: DDR PMU driver for Alibaba's T-Head Yitian 710 SoC, SVE
vector granule register added to the user regs together with SVE perf
extensions documentation.
- SVE updates: add HWCAP for SVE EBF16, update the SVE ABI documentation
to match the actual kernel behaviour (zeroing the registers on syscall
rather than "zeroed or preserved" previously).
- More conversions to automatic system registers generation.
- vDSO: use self-synchronising virtual counter access in gettimeofday()
if the architecture supports it.
- arm64 stacktrace cleanups and improvements.
- arm64 atomics improvements: always inline assembly, remove LL/SC
trampolines.
- Improve the reporting of EL1 exceptions: rework BTI and FPAC exception
handling, better EL1 undefs reporting.
- Cortex-A510 erratum 2658417: remove BF16 support due to incorrect
result.
- arm64 defconfig updates: build CoreSight as a module, enable options
necessary for docker, memory hotplug/hotremove, enable all PMUs
provided by Arm.
- arm64 ptrace() support for TPIDR2_EL0 (register provided with the SME
extensions).
- arm64 ftraces updates/fixes: fix module PLTs with mcount, remove
unused function.
- kselftest updates for arm64: simple HWCAP validation, FP stress test
improvements, validation of ZA regs in signal handlers, include larger
SVE and SME vector lengths in signal tests, various cleanups.
- arm64 alternatives (code patching) improvements to robustness and
consistency: replace cpucap static branches with equivalent
alternatives, associate callback alternatives with a cpucap.
- Miscellaneous updates: optimise kprobe performance of patching
single-step slots, simplify uaccess_mask_ptr(), move MTE registers
initialisation to C, support huge vmalloc() mappings, run softirqs on
the per-CPU IRQ stack, compat (arm32) misalignment fixups for
multiword accesses.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
- arm64 perf: DDR PMU driver for Alibaba's T-Head Yitian 710 SoC, SVE
vector granule register added to the user regs together with SVE perf
extensions documentation.
- SVE updates: add HWCAP for SVE EBF16, update the SVE ABI
documentation to match the actual kernel behaviour (zeroing the
registers on syscall rather than "zeroed or preserved" previously).
- More conversions to automatic system registers generation.
- vDSO: use self-synchronising virtual counter access in gettimeofday()
if the architecture supports it.
- arm64 stacktrace cleanups and improvements.
- arm64 atomics improvements: always inline assembly, remove LL/SC
trampolines.
- Improve the reporting of EL1 exceptions: rework BTI and FPAC
exception handling, better EL1 undefs reporting.
- Cortex-A510 erratum 2658417: remove BF16 support due to incorrect
result.
- arm64 defconfig updates: build CoreSight as a module, enable options
necessary for docker, memory hotplug/hotremove, enable all PMUs
provided by Arm.
- arm64 ptrace() support for TPIDR2_EL0 (register provided with the SME
extensions).
- arm64 ftraces updates/fixes: fix module PLTs with mcount, remove
unused function.
- kselftest updates for arm64: simple HWCAP validation, FP stress test
improvements, validation of ZA regs in signal handlers, include
larger SVE and SME vector lengths in signal tests, various cleanups.
- arm64 alternatives (code patching) improvements to robustness and
consistency: replace cpucap static branches with equivalent
alternatives, associate callback alternatives with a cpucap.
- Miscellaneous updates: optimise kprobe performance of patching
single-step slots, simplify uaccess_mask_ptr(), move MTE registers
initialisation to C, support huge vmalloc() mappings, run softirqs on
the per-CPU IRQ stack, compat (arm32) misalignment fixups for
multiword accesses.
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (126 commits)
arm64: alternatives: Use vdso/bits.h instead of linux/bits.h
arm64/kprobe: Optimize the performance of patching single-step slot
arm64: defconfig: Add Coresight as module
kselftest/arm64: Handle EINTR while reading data from children
kselftest/arm64: Flag fp-stress as exiting when we begin finishing up
kselftest/arm64: Don't repeat termination handler for fp-stress
ARM64: reloc_test: add __init/__exit annotations to module init/exit funcs
arm64/mm: fold check for KFENCE into can_set_direct_map()
arm64: ftrace: fix module PLTs with mcount
arm64: module: Remove unused plt_entry_is_initialized()
arm64: module: Make plt_equals_entry() static
arm64: fix the build with binutils 2.27
kselftest/arm64: Don't enable v8.5 for MTE selftest builds
arm64: uaccess: simplify uaccess_mask_ptr()
arm64: asm/perf_regs.h: Avoid C++-style comment in UAPI header
kselftest/arm64: Fix typo in hwcap check
arm64: mte: move register initialization to C
arm64: mm: handle ARM64_KERNEL_USES_PMD_MAPS in vmemmap_populate()
arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()
arm64/sve: Add Perf extensions documentation
...
Some VT-d hardware implementations invalidate all DMA remapping hardware
translation caches as part of SRTP flow. The VT-d spec adds a ESRTPS
(Enhanced Set Root Table Pointer Support, section 11.4.2 in VT-d spec)
capability bit to indicate this. With this bit set, software has no need
to issue the global invalidation request.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220919062523.3438951-3-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Some VT-d hardware implementations invalidate all interrupt remapping
hardware translation caches as part of SIRTP flow. The VT-d spec adds
a ESIRTPS (Enhanced Set Interrupt Remap Table Pointer Support, section
11.4.2 in VT-d spec) capability bit to indicate this.
The spec also states in 11.4.4 that hardware also performs global
invalidation on all interrupt remapping caches as part of Interrupt
Remapping Disable operation if ESIRTPS capability bit is set.
This checks the ESIRTPS capability bit and skip software global cache
invalidation if it's set.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220921065741.3572495-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This renaming better describes it is for first level page table (a.k.a
first stage page table since VT-d spec 3.4).
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220916071326.2223901-1-yi.l.liu@intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
It is not used anywhere in the tree. Remove it to avoid dead code.
No functional change intended.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220915081645.1834555-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Previously the PCI PASID and PRI capabilities are enabled in the path of
iommu device probe only if INTEL_IOMMU_SVM is configured and the device
supports ATS. As we've already decoupled the I/O page fault handler from
SVA, we could also decouple PASID and PRI enabling from it to make room
for growth of new features like kernel DMA with PASID, SIOV and nested
translation.
At the same time, the iommu_enable_dev_iotlb() helper is also called in
iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA) path. It's unnecessary
and duplicate. This cleanups this helper to make the code neat.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220915085814.2261409-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The existing I/O page fault handling code accesses the per-PASID SVA data
structures. This is unnecessary and makes the fault handling code only
suitable for SVA scenarios. This removes the SVA data accesses from the
I/O page fault reporting and responding code, so that the fault handling
code could be generic.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220914011821.400986-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The M1 Pro/Max/Ultra SoCs come with a new variant of DART which
supports a larger physical address space with a different PTE format.
Pass through the correct paddr address space size and the PTE format
to the io-pgtable code which will take care of the rest.
Signed-off-by: Sven Peter <sven@svenpeter.dev>
Co-developed-by: Janne Grunau <j@jannau.net>
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Hector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20220916094152.87137-6-j@jannau.net
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The DARTs present in the M1 Pro/Max/Ultra SoC use a diffent PTE format.
They support a 42bit physical address space by shifting the paddr and
extending its mask inside the PTE.
They also come with mandatory sub-page protection now which we just
configure to always allow access to the entire page. This feature is
already present but optional on the previous DARTs which allows to
unconditionally configure it.
Signed-off-by: Sven Peter <sven@svenpeter.dev>
Co-developed-by: Janne Grunau <j@jannau.net>
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Hector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20220916094152.87137-5-j@jannau.net
Signed-off-by: Joerg Roedel <jroedel@suse.de>
DART allows to only expose a subpage to the device. While this is an
optional feature on the M1 DARTs the new ones present on the Pro/Max
models require this field in every PTE.
Signed-off-by: Sven Peter <sven@svenpeter.dev>
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Hector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20220916094152.87137-4-j@jannau.net
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The pte format used by the DARTs found in the Apple M1 (t8103) is not
fully compatible with io-pgtable-arm. The 24 MSB are used for subpage
protection (mapping only parts of page) and conflict with the address
mask. In addition bit 1 is not available for tagging entries but disables
subpage protection. Subpage protection could be useful to support a CPU
granule of 4k with the fixed IOMMU page size of 16k.
The DARTs found on Apple M1 Pro/Max/Ultra use another different pte
format which is even less compatible. To support an output address size
of 42 bit the address is shifted down by 4. Subpage protection is
mandatory and bit 1 signifies uncached mappings used by the display
controller.
It would be advantageous to share code for all known Apple DART
variants to support common features. The page table allocator for DARTs
is less complex since it uses a two levels of translation table without
support for huge pages.
Signed-off-by: Janne Grunau <j@jannau.net>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Sven Peter <sven@svenpeter.dev>
Acked-by: Hector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20220916094152.87137-3-j@jannau.net
[ joro: Fix compile warning in __dart_alloc_pages()]
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add support for the M4Us found in the MT6795 Helio X10 SoC.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20220913151148.412312-4-angelogioacchino.delregno@collabora.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
In preparation for adding support for MT6795, add a new flag named
TF_PORT_TO_ADDR_MT8173 and use that instead of checking for m4u_plat
type in mtk_iommu_hw_init() to avoid seeing a long list of m4u_plat
checks there in the future.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20220913151148.412312-3-angelogioacchino.delregno@collabora.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
CHECK drivers/iommu/amd/iommu.c
drivers/iommu/amd/iommu.c:73:24: warning: symbol 'amd_iommu_ops' was not declared. Should it be static?
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220912063248.7909-6-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Coresight trace subsystem updates for v6.1 includes:
- Support for HiSilicon PTT trace
- Coresight cleanup of sysfs accessor functions, reduced
code size.
- Expose coresight timestamp source for ETMv4+
- DT binding updates to include missing properties
- Minor documentation, Kconfig text fixes.
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
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Merge tag 'coresight-next-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux into char-misc-next
Suzuki writes:
"coresight: Changes for v6.1
Coresight trace subsystem updates for v6.1 includes:
- Support for HiSilicon PTT trace
- Coresight cleanup of sysfs accessor functions, reduced
code size.
- Expose coresight timestamp source for ETMv4+
- DT binding updates to include missing properties
- Minor documentation, Kconfig text fixes.
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>"
* tag 'coresight-next-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux:
hwtracing: hisi_ptt: Fix up for "iommu/dma: Make header private"
MAINTAINERS: Add maintainer for HiSilicon PTT driver
docs: trace: Add HiSilicon PTT device driver documentation
hwtracing: hisi_ptt: Add tune function support for HiSilicon PCIe Tune and Trace device
hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device
iommu/arm-smmu-v3: Make default domain type of HiSilicon PTT device to identity
coresight: cti-sysfs: Mark coresight_cti_reg_store() as __maybe_unused
coresight: Make new csdev_access offsets unsigned
coresight: cti-sysfs: Re-use same functions for similar sysfs register accessors
coresight: Re-use same function for similar sysfs register accessors
coresight: Simplify sysfs accessors by using csdev_access abstraction
coresight: Remove unused function parameter
coresight: etm4x: docs: Add documentation for 'ts_source' sysfs interface
coresight: etm4x: Expose default timestamp source in sysfs
dt-bindings: arm: coresight-tmc: Add 'iommu' property
dt-bindings: arm: coresight: Add 'power-domains' property
coresight: docs: Fix a broken reference
coresight: trbe: fix Kconfig "its" grammar
This reverts commit 9cd4f14344.
Some issues were reported on the original commit. Some thunderbolt devices
don't work anymore due to the following DMA fault.
DMAR: DRHD: handling fault status reg 2
DMAR: [INTR-REMAP] Request device [09:00.0] fault index 0x8080
[fault reason 0x25]
Blocked a compatibility format interrupt request
Bring it back for now to avoid functional regression.
Fixes: 9cd4f14344 ("iommu/vt-d: Fix possible recursive locking in intel_iommu_init()")
Link: https://lore.kernel.org/linux-iommu/485A6EA5-6D58-42EA-B298-8571E97422DE@getmailspring.com/
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216497
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: <stable@vger.kernel.org> # 5.19.x
Reported-and-tested-by: George Hilliard <thirtythreeforty@gmail.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220920081701.3453504-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The AMD IOMMU driver cannot activate PASID mode on a RID without the RID's
translation being set to IDENTITY. Further it requires changing the RID's
page table layout from the normal v1 IOMMU_DOMAIN_IDENTITY layout to a
different v2 layout.
It does this by creating a new iommu_domain, configuring that domain for
v2 identity operation and then attaching it to the group, from within the
driver. This logic assumes the group is already set to the IDENTITY domain
and is being used by the DMA API.
However, since the ownership logic is based on the group's domain pointer
equaling the default domain to detect DMA API ownership, this causes it to
look like the group is not attached to the DMA API any more. This blocks
attaching drivers to any other devices in the group.
In a real system this manifests itself as the HD-audio devices on some AMD
platforms losing their device drivers.
Work around this unique behavior of the AMD driver by checking for
equality of IDENTITY domains based on their type, not their pointer
value. This allows the AMD driver to have two IDENTITY domains for
internal purposes without breaking the check.
Have the AMD driver properly declare that the special domain it created is
actually an IDENTITY domain.
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: stable@vger.kernel.org
Fixes: 512881eacf ("bus: platform,amba,fsl-mc,PCI: Add device DMA ownership management")
Reported-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0-v1-ea566e16b06b+811-amd_owner_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The global rwsem dmar_global_lock was introduced by commit 3a5670e8ac
("iommu/vt-d: Introduce a rwsem to protect global data structures"). It
is used to protect DMAR related global data from DMAR hotplug operations.
The dmar_global_lock used in the intel_iommu_init() might cause recursive
locking issue, for example, intel_iommu_get_resv_regions() is taking the
dmar_global_lock from within a section where intel_iommu_init() already
holds it via probe_acpi_namespace_devices().
Using dmar_global_lock in intel_iommu_init() could be relaxed since it is
unlikely that any IO board must be hot added before the IOMMU subsystem is
initialized. This eliminates the possible recursive locking issue by moving
down DMAR hotplug support after the IOMMU is initialized and removing the
uses of dmar_global_lock in intel_iommu_init().
Fixes: d5692d4af0 ("iommu/vt-d: Fix suspicious RCU usage in probe_acpi_namespace_devices()")
Reported-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/894db0ccae854b35c73814485569b634237b5538.1657034828.git.robin.murphy@arm.com
Link: https://lore.kernel.org/r/20220718235325.3952426-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
For some reason we refer to ID_AA64MMFR0_EL1.ASIDBits as ASID. Add BITS
into the name, bringing the naming into sync with DDI0487H.a. Due to the
large amount of MixedCase in this register which isn't really consistent
with either the kernel style or the majority of the architecture the use of
upper case is preserved. No functional changes.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-10-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64MMFR0_EL1 to follow the convention. No functional changes.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-5-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
A recent fix introduced viommu_capable() but other changes
from Robin change the function signature of the call-back it
is used for.
When both changes are merged a compile error will happen
because the function pointer types mismatch. Fix that by
updating the viommu_capable() signature after the merge.
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20220907151154.21911-1-joro@8bytes.org
The iovad->rcaches check in iova_rcache_get() is pretty much useless
without the same check in iova_rcache_insert().
Instead of adding this symmetric check to fastpath iova_rcache_insert(),
drop the check in iova_rcache_get() in favour of making the IOVA domain
rcache init more robust to failure in future.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1662557681-145906-4-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Two of the magazine helpers have BUG_ON() checks, as follows:
- iova_magazine_pop() - here we ensure that the mag is not empty. However
we already ensure that in the only caller, __iova_rcache_get().
- iova_magazine_push() - here we ensure that the mag is not full. However
we already ensure that in the only caller, __iova_rcache_insert().
As described, the two bug checks are pointless so drop them.
Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/1662557681-145906-3-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Since commit 32e92d9f6f ("iommu/iova: Separate out rcache init") it
has not been possible to have NULL CPU rcache "loaded" or "prev" magazine
pointers once the IOVA domain has been properly initialized. Previously it
was only possible to have NULL pointers from failure to allocate the
magazines in the IOVA domain initialization. The only other two functions
to modify these pointers - __iova_rcache_{get, insert}() - would already
ensure that these pointers were non-NULL if initially non-NULL.
As such, the mag NULL pointer checks in iova_magazine_full(),
iova_magazine_empty(), and iova_magazine_free_pfns() may be dropped.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/1662557681-145906-2-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The DMA operations of HiSilicon PTT device can only work properly with
identical mappings. So add a quirk for the device to force the domain
as passthrough.
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/20220816114414.4092-2-yangyicong@huawei.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
AMD IOMMU introduces support for Guest I/O protection where the request
from the I/O device without a PASID are treated as if they have PASID 0.
Co-developed-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20220825063939.8360-8-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Currently, PPR/ATS can be enabled only if the domain is type
identity mapping. However, when allowing the IOMMU v2 page table
to be used for DMA-API, the check is no longer valid.
Update the sanity check to only apply for when using AMD_IOMMU_V1
page table mode.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220825063939.8360-6-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The current function to enable IOMMU v2 also lock the domain.
In order to reuse the same code in different code path, in which
the domain has already been locked, refactor the function to separate
the locking from the enabling logic.
Co-developed-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20220825063939.8360-5-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Implement the map_pages() and unmap_pages() callback for the AMD IOMMU
driver to allow calls from iommu core to map and unmap multiple pages.
Also deprecate map/unmap callbacks.
Finally gatherer is not updated by iommu_v1_unmap_pages(). Hence pass
NULL instead of gather to iommu_v1_unmap_pages.
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220825063939.8360-4-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Implement the io_pgtable_ops->unmap_pages() callback for AMD driver
and deprecate io_pgtable_ops->unmap callback.
Also if fetch_pte() returns NULL then return from unmap_mapages()
instead of trying to continue to unmap remaining pages.
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220825063939.8360-3-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Commit e8ae0e140c ("vfio: Require that devices support DMA cache
coherence") requires IOMMU drivers to advertise
IOMMU_CAP_CACHE_COHERENCY, in order to be used by VFIO. Since VFIO does
not provide to userspace the ability to maintain coherency through cache
invalidations, it requires hardware coherency. Advertise the capability
in order to restore VFIO support.
The meaning of IOMMU_CAP_CACHE_COHERENCY also changed from "IOMMU can
enforce cache coherent DMA transactions" to "IOMMU_CACHE is supported".
While virtio-iommu cannot enforce coherency (of PCIe no-snoop
transactions), it does support IOMMU_CACHE.
We can distinguish different cases of non-coherent DMA:
(1) When accesses from a hardware endpoint are not coherent. The host
would describe such a device using firmware methods ('dma-coherent'
in device-tree, '_CCA' in ACPI), since they are also needed without
a vIOMMU. In this case mappings are created without IOMMU_CACHE.
virtio-iommu doesn't need any additional support. It sends the same
requests as for coherent devices.
(2) When the physical IOMMU supports non-cacheable mappings. Supporting
those would require a new feature in virtio-iommu, new PROBE request
property and MAP flags. Device drivers would use a new API to
discover this since it depends on the architecture and the physical
IOMMU.
(3) When the hardware supports PCIe no-snoop. It is possible for
assigned PCIe devices to issue no-snoop transactions, and the
virtio-iommu specification is lacking any mention of this.
Arm platforms don't necessarily support no-snoop, and those that do
cannot enforce coherency of no-snoop transactions. Device drivers
must be careful about assuming that no-snoop transactions won't end
up cached; see commit e02f5c1bb2 ("drm: disable uncached DMA
optimization for ARM and arm64"). On x86 platforms, the host may or
may not enforce coherency of no-snoop transactions with the physical
IOMMU. But according to the above commit, on x86 a driver which
assumes that no-snoop DMA is compatible with uncached CPU mappings
will also work if the host enforces coherency.
Although these issues are not specific to virtio-iommu, it could be
used to facilitate discovery and configuration of no-snoop. This
would require a new feature bit, PROBE property and ATTACH/MAP
flags.
Cc: stable@vger.kernel.org
Fixes: e8ae0e140c ("vfio: Require that devices support DMA cache coherence")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20220825154622.86759-1-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
