Commit Graph

2150 Commits

Author SHA1 Message Date
Jason A. Donenfeld
622754e84b stackprotector: actually use get_random_canary()
The RNG always mixes in the Linux version extremely early in boot. It
also always includes a cycle counter, not only during early boot, but
each and every time it is invoked prior to being fully initialized.
Together, this means that the use of additional xors inside of the
various stackprotector.h files is superfluous and over-complicated.
Instead, we can get exactly the same thing, but better, by just calling
`get_random_canary()`.

Acked-by: Guo Ren <guoren@kernel.org> # for csky
Acked-by: Catalin Marinas <catalin.marinas@arm.com> # for arm64
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-11-18 02:18:10 +01:00
Linus Torvalds
676cb49573 - hfs and hfsplus kmap API modernization from Fabio Francesco
- Valentin Schneider makes crash-kexec work properly when invoked from
   an NMI-time panic.
 
 - ntfs bugfixes from Hawkins Jiawei
 
 - Jiebin Sun improves IPC msg scalability by replacing atomic_t's with
   percpu counters.
 
 - nilfs2 cleanups from Minghao Chi
 
 - lots of other single patches all over the tree!
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCY0Yf0gAKCRDdBJ7gKXxA
 joapAQDT1d1zu7T8yf9cQXkYnZVuBKCjxKE/IsYvqaq1a42MjQD/SeWZg0wV05B8
 DhJPj9nkEp6R3Rj3Mssip+3vNuceAQM=
 =lUQY
 -----END PGP SIGNATURE-----

Merge tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - hfs and hfsplus kmap API modernization (Fabio Francesco)

 - make crash-kexec work properly when invoked from an NMI-time panic
   (Valentin Schneider)

 - ntfs bugfixes (Hawkins Jiawei)

 - improve IPC msg scalability by replacing atomic_t's with percpu
   counters (Jiebin Sun)

 - nilfs2 cleanups (Minghao Chi)

 - lots of other single patches all over the tree!

* tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (71 commits)
  include/linux/entry-common.h: remove has_signal comment of arch_do_signal_or_restart() prototype
  proc: test how it holds up with mapping'less process
  mailmap: update Frank Rowand email address
  ia64: mca: use strscpy() is more robust and safer
  init/Kconfig: fix unmet direct dependencies
  ia64: update config files
  nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
  fork: remove duplicate included header files
  init/main.c: remove unnecessary (void*) conversions
  proc: mark more files as permanent
  nilfs2: remove the unneeded result variable
  nilfs2: delete unnecessary checks before brelse()
  checkpatch: warn for non-standard fixes tag style
  usr/gen_init_cpio.c: remove unnecessary -1 values from int file
  ipc/msg: mitigate the lock contention with percpu counter
  percpu: add percpu_counter_add_local and percpu_counter_sub_local
  fs/ocfs2: fix repeated words in comments
  relay: use kvcalloc to alloc page array in relay_alloc_page_array
  proc: make config PROC_CHILDREN depend on PROC_FS
  fs: uninline inode_maybe_inc_iversion()
  ...
2022-10-12 11:00:22 -07:00
Linus Torvalds
27bc50fc90 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
linux-next for a couple of months without, to my knowledge, any negative
   reports (or any positive ones, come to that).
 
 - Also the Maple Tree from Liam R.  Howlett.  An overlapping range-based
   tree for vmas.  It it apparently slight more efficient in its own right,
   but is mainly targeted at enabling work to reduce mmap_lock contention.
 
   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.
 
   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   (https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com).
   This has yet to be addressed due to Liam's unfortunately timed
   vacation.  He is now back and we'll get this fixed up.
 
 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer.  It uses
   clang-generated instrumentation to detect used-unintialized bugs down to
   the single bit level.
 
   KMSAN keeps finding bugs.  New ones, as well as the legacy ones.
 
 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.
 
 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support
   file/shmem-backed pages.
 
 - userfaultfd updates from Axel Rasmussen
 
 - zsmalloc cleanups from Alexey Romanov
 
 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure
 
 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.
 
 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.
 
 - memcg cleanups from Kairui Song.
 
 - memcg fixes and cleanups from Johannes Weiner.
 
 - Vishal Moola provides more folio conversions
 
 - Zhang Yi removed ll_rw_block() :(
 
 - migration enhancements from Peter Xu
 
 - migration error-path bugfixes from Huang Ying
 
 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths.  For optimizations by PMEM drivers, DRM
   drivers, etc.
 
 - vma merging improvements from Jakub Matěn.
 
 - NUMA hinting cleanups from David Hildenbrand.
 
 - xu xin added aditional userspace visibility into KSM merging activity.
 
 - THP & KSM code consolidation from Qi Zheng.
 
 - more folio work from Matthew Wilcox.
 
 - KASAN updates from Andrey Konovalov.
 
 - DAMON cleanups from Kaixu Xia.
 
 - DAMON work from SeongJae Park: fixes, cleanups.
 
 - hugetlb sysfs cleanups from Muchun Song.
 
 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCY0HaPgAKCRDdBJ7gKXxA
 joPjAQDZ5LlRCMWZ1oxLP2NOTp6nm63q9PWcGnmY50FjD/dNlwEAnx7OejCLWGWf
 bbTuk6U2+TKgJa4X7+pbbejeoqnt5QU=
 =xfWx
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
   linux-next for a couple of months without, to my knowledge, any
   negative reports (or any positive ones, come to that).

 - Also the Maple Tree from Liam Howlett. An overlapping range-based
   tree for vmas. It it apparently slightly more efficient in its own
   right, but is mainly targeted at enabling work to reduce mmap_lock
   contention.

   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.

   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   at [1]. This has yet to be addressed due to Liam's unfortunately
   timed vacation. He is now back and we'll get this fixed up.

 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses
   clang-generated instrumentation to detect used-unintialized bugs down
   to the single bit level.

   KMSAN keeps finding bugs. New ones, as well as the legacy ones.

 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.

 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to
   support file/shmem-backed pages.

 - userfaultfd updates from Axel Rasmussen

 - zsmalloc cleanups from Alexey Romanov

 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and
   memory-failure

 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.

 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.

 - memcg cleanups from Kairui Song.

 - memcg fixes and cleanups from Johannes Weiner.

 - Vishal Moola provides more folio conversions

 - Zhang Yi removed ll_rw_block() :(

 - migration enhancements from Peter Xu

 - migration error-path bugfixes from Huang Ying

 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths. For optimizations by PMEM drivers, DRM
   drivers, etc.

 - vma merging improvements from Jakub Matěn.

 - NUMA hinting cleanups from David Hildenbrand.

 - xu xin added aditional userspace visibility into KSM merging
   activity.

 - THP & KSM code consolidation from Qi Zheng.

 - more folio work from Matthew Wilcox.

 - KASAN updates from Andrey Konovalov.

 - DAMON cleanups from Kaixu Xia.

 - DAMON work from SeongJae Park: fixes, cleanups.

 - hugetlb sysfs cleanups from Muchun Song.

 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.

Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1]

* tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits)
  hugetlb: allocate vma lock for all sharable vmas
  hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer
  hugetlb: fix vma lock handling during split vma and range unmapping
  mglru: mm/vmscan.c: fix imprecise comments
  mm/mglru: don't sync disk for each aging cycle
  mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol
  mm: memcontrol: use do_memsw_account() in a few more places
  mm: memcontrol: deprecate swapaccounting=0 mode
  mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled
  mm/secretmem: remove reduntant return value
  mm/hugetlb: add available_huge_pages() func
  mm: remove unused inline functions from include/linux/mm_inline.h
  selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory
  selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd
  selftests/vm: add thp collapse shmem testing
  selftests/vm: add thp collapse file and tmpfs testing
  selftests/vm: modularize thp collapse memory operations
  selftests/vm: dedup THP helpers
  mm/khugepaged: add tracepoint to hpage_collapse_scan_file()
  mm/madvise: add file and shmem support to MADV_COLLAPSE
  ...
2022-10-10 17:53:04 -07:00
Linus Torvalds
e2302539dd Xtensa updates for v6.1
- add support for FDPIC and static PIE executable formats for noMMU
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEK2eFS5jlMn3N6xfYUfnMkfg/oEQFAmNEg54THGpjbXZia2Jj
 QGdtYWlsLmNvbQAKCRBR+cyR+D+gRDZHD/9FqjYXY16y66WRKbUN4DCzzYLuxWBV
 3mSdZyqjw+AB24XBbY4i81ppvdyTnA3i2nNrbjq6OWIp9uWUyGXdw+dnmGRlgulc
 EJLyRBbaal1YD+Tohn8n4sAuE8zpOtL1PHIb2Z7CySXVSNV7JxvIyUD43o9bUW45
 Qse0BWGq1hZHmFWeJ4J8K4NDAPxMEWCOrIbqjyEMODKOUy0zKWw1OT7fKDMEP/zm
 7H5o9k1QD0AcZPVAUGDq6PChSxjv8avAfD635UzvsYPpd/6ovnNT3bTrApARErdv
 XwgtVPcMEQ8oEr6ALAQGlmu092Cb9jwXZFnaYW1GBG8m6uT6BXybWf69zF8l6RrG
 lKcPc6F9HpHNR8ukfJ3pnEiHBGPQhu3lA6WDj9+URKY+BSbBDa3jtpf8p3uTRktb
 SfK7EXl9MSYfSq/tPqVLWL71L97Kx1n4OxylqU+UU0+SSfm6buZSsAMKPCUOjdKI
 SvTDFUk3XKIARAnT8KD8Nj1opmpRHSAi5r6LXpu6v2/InBx7SrGzVuh05yJ2jGUO
 0qeiDKTKTg254oUlnW9yVXkxrcu2THar17v4YgA6zu/zk5sOJSebCLly9upX+q4C
 oIXGSPB5UQi+cluEfYpvAo42YTONuDSaA/p26EeUhnBsbgIhInTi3zLWKXYWwezC
 YSQAsD1mOZICxg==
 =quUm
 -----END PGP SIGNATURE-----

Merge tag 'xtensa-20221010' of https://github.com/jcmvbkbc/linux-xtensa

Pull xtensa updates from Max Filippov:

 - add support for FDPIC and static PIE executable formats for noMMU

* tag 'xtensa-20221010' of https://github.com/jcmvbkbc/linux-xtensa:
  xtensa: add FDPIC and static PIE support for noMMU
  xtensa: clean up ELF_PLAT_INIT macro
2022-10-10 14:21:11 -07:00
Masahiro Yamada
ce697ccee1 kbuild: remove head-y syntax
Kbuild puts the objects listed in head-y at the head of vmlinux.
Conventionally, we do this for head*.S, which contains the kernel entry
point.

A counter approach is to control the section order by the linker script.
Actually, the code marked as __HEAD goes into the ".head.text" section,
which is placed before the normal ".text" section.

I do not know if both of them are needed. From the build system
perspective, head-y is not mandatory. If you can achieve the proper code
placement by the linker script only, it would be cleaner.

I collected the current head-y objects into head-object-list.txt. It is
a whitelist. My hope is it will be reduced in the long run.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2022-10-02 18:06:03 +09:00
Masahiro Yamada
3216484550 kbuild: use obj-y instead extra-y for objects placed at the head
The objects placed at the head of vmlinux need special treatments:

 - arch/$(SRCARCH)/Makefile adds them to head-y in order to place
   them before other archives in the linker command line.

 - arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of
   obj-y to avoid them going into built-in.a.

This commit gets rid of the latter.

Create vmlinux.a to collect all the objects that are unconditionally
linked to vmlinux. The objects listed in head-y are moved to the head
of vmlinux.a by using 'ar m'.

With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y
for builtin objects.

There is no *.o that is directly linked to vmlinux. Drop unneeded code
in scripts/clang-tools/gen_compile_commands.py.

$(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested
by Nathan Chancellor [1].

[1]: https://lore.kernel.org/llvm/YyjjT5gQ2hGMH0ni@dev-arch.thelio-3990X/

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2022-10-02 18:04:05 +09:00
Matthew Wilcox (Oracle)
49c40fb4b8 xtensa: remove vma linked list walks
Use the VMA iterator instead.  Since VMA can no longer be NULL in the
loop, then deal with out-of-memory outside the loop.  This means a
slightly longer run time in the failure case (-ENOMEM) - it will run to
the end of the VMAs before erroring instead of in the middle of the loop.

Link: https://lkml.kernel.org/r/20220906194824.2110408-37-Liam.Howlett@oracle.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-26 19:46:20 -07:00
Max Filippov
e3ddb8bbe0 xtensa: add FDPIC and static PIE support for noMMU
Define ELFOSABI_XTENSA_FDPIC and use it as an OSABI tag in the ELF
header to distinguish FDPIC ELF files from regular ELF files.
Define ELF_FDPIC_PLAT_INIT and put executable map, interpreter map and
executable dynamic section addresses into registers a4..a6.
Update start_thread macro to preserve register values in the current
register window.
Add definitions for PTRACE_GETFDPIC, PTRACE_GETFDPIC_EXEC and
PTRACE_GETFDPIC_INTERP.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-09-13 18:28:00 -07:00
Max Filippov
ccd2d9df6e xtensa: clean up ELF_PLAT_INIT macro
Wrap _r in parentheses in the macro body.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-09-13 18:21:56 -07:00
Kefeng Wang
2be9880dc8 kernel: exit: cleanup release_thread()
Only x86 has own release_thread(), introduce a new weak release_thread()
function to clean empty definitions in other ARCHs.

Link: https://lkml.kernel.org/r/20220819014406.32266-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Guo Ren <guoren@kernel.org>				[csky]
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Brian Cain <bcain@quicinc.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>			[powerpc]
Acked-by: Stafford Horne <shorne@gmail.com>			[openrisc]
Acked-by: Catalin Marinas <catalin.marinas@arm.com>		[arm64]
Acked-by: Huacai Chen <chenhuacai@kernel.org>			[LoongArch]
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org> [csky]
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Xuerui Wang <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:07 -07:00
Arnd Bergmann
64367f2e4f treewide: defconfig: address renamed CONFIG_DEBUG_INFO=y
CONFIG_DEBUG_INFO is now implicitly selected if one picks one of the
explicit options that could be DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT,
DEBUG_INFO_DWARF4, DEBUG_INFO_DWARF5.

This was actually not what I had in mind when I suggested making it a
'choice' statement, but it's too late to change again now, and the Kconfig
logic is more sensible in the new form.

Change any defconfig file that had CONFIG_DEBUG_INFO enabled but did not
pick DWARF4 or DWARF5 explicitly to now pick the toolchain default.

Link: https://lkml.kernel.org/r/20220811114609.2097335-1-arnd@kernel.org
Fixes: f9b3cd2457 ("Kconfig.debug: make DEBUG_INFO selectable from a choice")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Cc: Rich Felker <dalias@libc.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:05 -07:00
Zi Yan
0192445cb2 arch: mm: rename FORCE_MAX_ZONEORDER to ARCH_FORCE_MAX_ORDER
This Kconfig option is used by individual arch to set its desired
MAX_ORDER.  Rename it to reflect its actual use.

Link: https://lkml.kernel.org/r/20220815143959.1511278-1-zi.yan@sent.com
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Acked-by: Guo Ren <guoren@kernel.org>			[csky]
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>	[arm64]
Acked-by: Huacai Chen <chenhuacai@kernel.org>		[LoongArch]
Acked-by: Michael Ellerman <mpe@ellerman.id.au>		[powerpc]
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Qin Jian <qinjian@cqplus1.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 20:25:56 -07:00
Zach O'Keefe
7d8faaf155 mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse
This idea was introduced by David Rientjes[1].

Introduce a new madvise mode, MADV_COLLAPSE, that allows users to request
a synchronous collapse of memory at their own expense.

The benefits of this approach are:

* CPU is charged to the process that wants to spend the cycles for the
  THP
* Avoid unpredictable timing of khugepaged collapse

Semantics

This call is independent of the system-wide THP sysfs settings, but will
fail for memory marked VM_NOHUGEPAGE.  If the ranges provided span
multiple VMAs, the semantics of the collapse over each VMA is independent
from the others.  This implies a hugepage cannot cross a VMA boundary.  If
collapse of a given hugepage-aligned/sized region fails, the operation may
continue to attempt collapsing the remainder of memory specified.

The memory ranges provided must be page-aligned, but are not required to
be hugepage-aligned.  If the memory ranges are not hugepage-aligned, the
start/end of the range will be clamped to the first/last hugepage-aligned
address covered by said range.  The memory ranges must span at least one
hugepage-sized region.

All non-resident pages covered by the range will first be
swapped/faulted-in, before being internally copied onto a freshly
allocated hugepage.  Unmapped pages will have their data directly
initialized to 0 in the new hugepage.  However, for every eligible
hugepage aligned/sized region to-be collapsed, at least one page must
currently be backed by memory (a PMD covering the address range must
already exist).

Allocation for the new hugepage may enter direct reclaim and/or
compaction, regardless of VMA flags.  When the system has multiple NUMA
nodes, the hugepage will be allocated from the node providing the most
native pages.  This operation operates on the current state of the
specified process and makes no persistent changes or guarantees on how
pages will be mapped, constructed, or faulted in the future

Return Value

If all hugepage-sized/aligned regions covered by the provided range were
either successfully collapsed, or were already PMD-mapped THPs, this
operation will be deemed successful.  On success, process_madvise(2)
returns the number of bytes advised, and madvise(2) returns 0.  Else, -1
is returned and errno is set to indicate the error for the most-recently
attempted hugepage collapse.  Note that many failures might have occurred,
since the operation may continue to collapse in the event a single
hugepage-sized/aligned region fails.

	ENOMEM	Memory allocation failed or VMA not found
	EBUSY	Memcg charging failed
	EAGAIN	Required resource temporarily unavailable.  Try again
		might succeed.
	EINVAL	Other error: No PMD found, subpage doesn't have Present
		bit set, "Special" page no backed by struct page, VMA
		incorrectly sized, address not page-aligned, ...

Most notable here is ENOMEM and EBUSY (new to madvise) which are intended
to provide the caller with actionable feedback so they may take an
appropriate fallback measure.

Use Cases

An immediate user of this new functionality are malloc() implementations
that manage memory in hugepage-sized chunks, but sometimes subrelease
memory back to the system in native-sized chunks via MADV_DONTNEED;
zapping the pmd.  Later, when the memory is hot, the implementation could
madvise(MADV_COLLAPSE) to re-back the memory by THPs to regain hugepage
coverage and dTLB performance.  TCMalloc is such an implementation that
could benefit from this[2].

Only privately-mapped anon memory is supported for now, but additional
support for file, shmem, and HugeTLB high-granularity mappings[2] is
expected.  File and tmpfs/shmem support would permit:

* Backing executable text by THPs.  Current support provided by
  CONFIG_READ_ONLY_THP_FOR_FS may take a long time on a large system which
  might impair services from serving at their full rated load after
  (re)starting.  Tricks like mremap(2)'ing text onto anonymous memory to
  immediately realize iTLB performance prevents page sharing and demand
  paging, both of which increase steady state memory footprint.  With
  MADV_COLLAPSE, we get the best of both worlds: Peak upfront performance
  and lower RAM footprints.
* Backing guest memory by hugapages after the memory contents have been
  migrated in native-page-sized chunks to a new host, in a
  userfaultfd-based live-migration stack.

[1] https://lore.kernel.org/linux-mm/d098c392-273a-36a4-1a29-59731cdf5d3d@google.com/
[2] https://github.com/google/tcmalloc/tree/master/tcmalloc

[jrdr.linux@gmail.com: avoid possible memory leak in failure path]
  Link: https://lkml.kernel.org/r/20220713024109.62810-1-jrdr.linux@gmail.com
[zokeefe@google.com add missing kfree() to madvise_collapse()]
  Link: https://lore.kernel.org/linux-mm/20220713024109.62810-1-jrdr.linux@gmail.com/
  Link: https://lkml.kernel.org/r/20220713161851.1879439-1-zokeefe@google.com
[zokeefe@google.com: delay computation of hpage boundaries until use]]
  Link: https://lkml.kernel.org/r/20220720140603.1958773-4-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220706235936.2197195-10-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Suggested-by: David Rientjes <rientjes@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 20:25:46 -07:00
Linus Torvalds
6614a3c316 - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe
Lin, Yang Shi, Anshuman Khandual and Mike Rapoport
 
 - Some kmemleak fixes from Patrick Wang and Waiman Long
 
 - DAMON updates from SeongJae Park
 
 - memcg debug/visibility work from Roman Gushchin
 
 - vmalloc speedup from Uladzislau Rezki
 
 - more folio conversion work from Matthew Wilcox
 
 - enhancements for coherent device memory mapping from Alex Sierra
 
 - addition of shared pages tracking and CoW support for fsdax, from
   Shiyang Ruan
 
 - hugetlb optimizations from Mike Kravetz
 
 - Mel Gorman has contributed some pagealloc changes to improve latency
   and realtime behaviour.
 
 - mprotect soft-dirty checking has been improved by Peter Xu
 
 - Many other singleton patches all over the place
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCYuravgAKCRDdBJ7gKXxA
 jpqSAQDrXSdII+ht9kSHlaCVYjqRFQz/rRvURQrWQV74f6aeiAD+NHHeDPwZn11/
 SPktqEUrF1pxnGQxqLh1kUFUhsVZQgE=
 =w/UH
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Most of the MM queue. A few things are still pending.

  Liam's maple tree rework didn't make it. This has resulted in a few
  other minor patch series being held over for next time.

  Multi-gen LRU still isn't merged as we were waiting for mapletree to
  stabilize. The current plan is to merge MGLRU into -mm soon and to
  later reintroduce mapletree, with a view to hopefully getting both
  into 6.1-rc1.

  Summary:

   - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe
     Lin, Yang Shi, Anshuman Khandual and Mike Rapoport

   - Some kmemleak fixes from Patrick Wang and Waiman Long

   - DAMON updates from SeongJae Park

   - memcg debug/visibility work from Roman Gushchin

   - vmalloc speedup from Uladzislau Rezki

   - more folio conversion work from Matthew Wilcox

   - enhancements for coherent device memory mapping from Alex Sierra

   - addition of shared pages tracking and CoW support for fsdax, from
     Shiyang Ruan

   - hugetlb optimizations from Mike Kravetz

   - Mel Gorman has contributed some pagealloc changes to improve
     latency and realtime behaviour.

   - mprotect soft-dirty checking has been improved by Peter Xu

   - Many other singleton patches all over the place"

 [ XFS merge from hell as per Darrick Wong in

   https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ]

* tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits)
  tools/testing/selftests/vm/hmm-tests.c: fix build
  mm: Kconfig: fix typo
  mm: memory-failure: convert to pr_fmt()
  mm: use is_zone_movable_page() helper
  hugetlbfs: fix inaccurate comment in hugetlbfs_statfs()
  hugetlbfs: cleanup some comments in inode.c
  hugetlbfs: remove unneeded header file
  hugetlbfs: remove unneeded hugetlbfs_ops forward declaration
  hugetlbfs: use helper macro SZ_1{K,M}
  mm: cleanup is_highmem()
  mm/hmm: add a test for cross device private faults
  selftests: add soft-dirty into run_vmtests.sh
  selftests: soft-dirty: add test for mprotect
  mm/mprotect: fix soft-dirty check in can_change_pte_writable()
  mm: memcontrol: fix potential oom_lock recursion deadlock
  mm/gup.c: fix formatting in check_and_migrate_movable_page()
  xfs: fail dax mount if reflink is enabled on a partition
  mm/memcontrol.c: remove the redundant updating of stats_flush_threshold
  userfaultfd: don't fail on unrecognized features
  hugetlb_cgroup: fix wrong hugetlb cgroup numa stat
  ...
2022-08-05 16:32:45 -07:00
Linus Torvalds
3bd6e5854b asm-generic: updates for 6.0
There are three independent sets of changes:
 
  - Sai Prakash Ranjan adds tracing support to the asm-generic
    version of the MMIO accessors, which is intended to help
    understand problems with device drivers and has been part
    of Qualcomm's vendor kernels for many years.
 
  - A patch from Sebastian Siewior to rework the handling of
    IRQ stacks in softirqs across architectures, which is
    needed for enabling PREEMPT_RT.
 
  - The last patch to remove the CONFIG_VIRT_TO_BUS option and
    some of the code behind that, after the last users of this
    old interface made it in through the netdev, scsi, media and
    staging trees.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEo6/YBQwIrVS28WGKmmx57+YAGNkFAmLqPPEACgkQmmx57+YA
 GNlUbQ/+NpIsiA0JUrCGtySt8KrLHdA2dH9lJOR5/iuxfphscPFfWtpcPvcXQWmt
 a8u7wyI8SHW1ku4U0Y5sO0dBSldDnoIqJ5t4X5d7YNU9yVtEtucqQhZf+GkrPlVD
 1HkRu05B7y0k2BMn7BLhSvkpafs3f1lNGXjs8oFBdOF1/zwp/GjcrfCK7KFzqjwU
 dYrX0SOFlKFd4BZC75VfK+XcKg4LtwIOmJraRRl7alz2Q5Oop2hgjgZxXDPf//vn
 SPOhXJN/97i1FUpY2TkfHVH1NxbPfjCV4pUnjmLG0Y4NSy9UQ/ZcXHcywIdeuhfa
 0LySOIsAqBeccpYYYdg2ubiMDZOXkBfANu/sB9o/EhoHfB4svrbPRDhBIQZMFXJr
 MJYu+IYce2rvydA/nydo4q++pxR8v1ES1ZIo8bDux+q1CI/zbpQV+f98kPVRA0M7
 ajc+5GTIqNIsvHzzadq7eYxcj5Bi8Li2JA9sVkAQ+6iq1TVyeYayMc9eYwONlmqw
 MD+PFYc651pKtXZCfkLXPIKSwS0uPqBndAibuVhpZ0hxWaCBBdKvY9mrWcPxt0kA
 tMR8lrosbbrV2K48BFdWTOHvCs2FhHQxPGVPZ/iWuxTA0hHZ9tUlaEkSX+VM57IU
 KCYQLdWzT8J9vrgqSbgYKlb6pSPz6FIjTfut6NZMmshIbavHV/Q=
 =aTR0
 -----END PGP SIGNATURE-----

Merge tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic updates from Arnd Bergmann:
 "There are three independent sets of changes:

   - Sai Prakash Ranjan adds tracing support to the asm-generic version
     of the MMIO accessors, which is intended to help understand
     problems with device drivers and has been part of Qualcomm's vendor
     kernels for many years

   - A patch from Sebastian Siewior to rework the handling of IRQ stacks
     in softirqs across architectures, which is needed for enabling
     PREEMPT_RT

   - The last patch to remove the CONFIG_VIRT_TO_BUS option and some of
     the code behind that, after the last users of this old interface
     made it in through the netdev, scsi, media and staging trees"

* tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  uapi: asm-generic: fcntl: Fix typo 'the the' in comment
  arch/*/: remove CONFIG_VIRT_TO_BUS
  soc: qcom: geni: Disable MMIO tracing for GENI SE
  serial: qcom_geni_serial: Disable MMIO tracing for geni serial
  asm-generic/io: Add logging support for MMIO accessors
  KVM: arm64: Add a flag to disable MMIO trace for nVHE KVM
  lib: Add register read/write tracing support
  drm/meson: Fix overflow implicit truncation warnings
  irqchip/tegra: Fix overflow implicit truncation warnings
  coresight: etm4x: Use asm-generic IO memory barriers
  arm64: io: Use asm-generic high level MMIO accessors
  arch/*: Disable softirq stacks on PREEMPT_RT.
2022-08-05 10:07:23 -07:00
Linus Torvalds
eff0cb3d91 pci-v5.20-changes
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCgAyFiEEgMe7l+5h9hnxdsnuWYigwDrT+vwFAmLr+2wUHGJoZWxnYWFz
 QGdvb2dsZS5jb20ACgkQWYigwDrT+vxfZg//eChkC2EUdT6K3zuQDbJJhsGcuOQF
 lnZuUyDn4xw7BkEoZf8V6YdAnp7VvgKhLOq1/q3Geu/LBbCaczoEogOCaR/WcVOs
 C+MsN0RWZQtgfuZKncQoqp25NeLPK9PFToeiIX/xViAYZF7NVjDY7XQiZHQ6JkEA
 /7cUqv/4nS3KCMsKjfmiOxGnqohMWtICiw9qjFvJ40PEDnNB1b53rkiVTxBFePpI
 ePfsRfi/C7klE3xNfoiEgrPp+Jfw+oShsCwXUsId7bEL2oLBc7ClqP05ZYZD3bTK
 QQYyZ12Cq8TysciYpUGBjBnywUHS5DIO5YaV3wxyVAR2Z+6GY2/QVjOa2kKvoK0o
 Hba6TJf8bL58AhSI8Q62pBM0sS7dqJSff+9c2BGpZvII5spP/rQQLlJO56TJjwkw
 Dlf0d3thhZOc9vSKjKw+0v0FdAyc4L11EOwUsw95jZeT5WWgqJYGFnWPZwqBI1KM
 DI1E5wVO5tA2H3NEn+BTTHbLWL+UppqyXPXBHiW52b2q5Bt8fJWMsFvnEEjclxmG
 pYCI7VgF8jqbYKxjobxPFY2x6PH9hfaGMxwzZSdOX6e/Eh+1esgyyaC5APpCO+Pp
 e4OkJaOzCmggrD0jYeLWu+yDm5KRrYo5cdfKHrKgAof0Am41lAa1OhJ2iH4ckNqP
 1qmHereDOe0zNVw=
 =9TAR
 -----END PGP SIGNATURE-----

Merge tag 'pci-v5.20-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Consolidate duplicated 'next function' scanning and extend to allow
     'isolated functions' on s390, similar to existing hypervisors
     (Niklas Schnelle)

  Resource management:
   - Implement pci_iobar_pfn() for sparc, which allows us to remove the
     sparc-specific pci_mmap_page_range() and pci_mmap_resource_range().

     This removes the ability to map the entire PCI I/O space using
     /proc/bus/pci, but we believe that's already been broken since
     v2.6.28 (Arnd Bergmann)

   - Move common PCI definitions to asm-generic/pci.h and rework others
     to be be more specific and more encapsulated in arches that need
     them (Stafford Horne)

  Power management:

   - Convert drivers to new *_PM_OPS macros to avoid need for '#ifdef
     CONFIG_PM_SLEEP' or '__maybe_unused' (Bjorn Helgaas)

  Virtualization:

   - Add ACS quirk for Broadcom BCM5750x multifunction NICs that isolate
     the functions but don't advertise an ACS capability (Pavan Chebbi)

  Error handling:

   - Clear PCI Status register during enumeration in case firmware left
     errors logged (Kai-Heng Feng)

   - When we have native control of AER, enable error reporting for all
     devices that support AER. Previously only a few drivers enabled
     this (Stefan Roese)

   - Keep AER error reporting enabled for switches. Previously we
     enabled this during enumeration but immediately disabled it (Stefan
     Roese)

   - Iterate over error counters instead of error strings to avoid
     printing junk in AER sysfs counters (Mohamed Khalfella)

  ASPM:

   - Remove pcie_aspm_pm_state_change() so ASPM config changes, e.g.,
     via sysfs, are not lost across power state changes (Kai-Heng Feng)

  Endpoint framework:

   - Don't stop an EPC when unbinding an EPF from it (Shunsuke Mie)

  Endpoint embedded DMA controller driver:

   - Simplify and clean up support for the DesignWare embedded DMA
     (eDMA) controller (Frank Li, Serge Semin)

  Broadcom STB PCIe controller driver:

   - Avoid config space accesses when link is down because we can't
     recover from the CPU aborts these cause (Jim Quinlan)

   - Look for power regulators described under Root Ports in DT and
     enable them before scanning the secondary bus (Jim Quinlan)

   - Disable/enable regulators in suspend/resume (Jim Quinlan)

  Freescale i.MX6 PCIe controller driver:

   - Simplify and clean up clock and PHY management (Richard Zhu)

   - Disable/enable regulators in suspend/resume (Richard Zhu)

   - Set PCIE_DBI_RO_WR_EN before writing DBI registers (Richard Zhu)

   - Allow speeds faster than Gen2 (Richard Zhu)

   - Make link being down a non-fatal error so controller probe doesn't
     fail if there are no Endpoints connected (Richard Zhu)

  Loongson PCIe controller driver:

   - Add ACPI and MCFG support for Loongson LS7A (Huacai Chen)

   - Avoid config reads to non-existent LS2K/LS7A devices because a
     hardware defect causes machine hangs (Huacai Chen)

   - Work around LS7A integrated devices that report incorrect Interrupt
     Pin values (Jianmin Lv)

  Marvell Aardvark PCIe controller driver:

   - Add support for AER and Slot capability on emulated bridge (Pali
     Rohár)

  MediaTek PCIe controller driver:

   - Add Airoha EN7532 to DT binding (John Crispin)

   - Allow building of driver for ARCH_AIROHA (Felix Fietkau)

  MediaTek PCIe Gen3 controller driver:

   - Print decoded LTSSM state when the link doesn't come up (Jianjun
     Wang)

  NVIDIA Tegra194 PCIe controller driver:

   - Convert DT binding to json-schema (Vidya Sagar)

   - Add DT bindings and driver support for Tegra234 Root Port and
     Endpoint mode (Vidya Sagar)

   - Fix some Root Port interrupt handling issues (Vidya Sagar)

   - Set default Max Payload Size to 256 bytes (Vidya Sagar)

   - Fix Data Link Feature capability programming (Vidya Sagar)

   - Extend Endpoint mode support to devices beyond Controller-5 (Vidya
     Sagar)

  Qualcomm PCIe controller driver:

   - Rework clock, reset, PHY power-on ordering to avoid hangs and
     improve consistency (Robert Marko, Christian Marangi)

   - Move pipe_clk handling to PHY drivers (Dmitry Baryshkov)

   - Add IPQ60xx support (Selvam Sathappan Periakaruppan)

   - Allow ASPM L1 and substates for 2.7.0 (Krishna chaitanya chundru)

   - Add support for more than 32 MSI interrupts (Dmitry Baryshkov)

  Renesas R-Car PCIe controller driver:

   - Convert DT binding to json-schema (Herve Codina)

   - Add Renesas RZ/N1D (R9A06G032) to rcar-gen2 DT binding and driver
     (Herve Codina)

  Samsung Exynos PCIe controller driver:

   - Fix phy-exynos-pcie driver so it follows the 'phy_init() before
     phy_power_on()' PHY programming model (Marek Szyprowski)

  Synopsys DesignWare PCIe controller driver:

   - Simplify and clean up the DWC core extensively (Serge Semin)

   - Fix an issue with programming the ATU for regions that cross a 4GB
     boundary (Serge Semin)

   - Enable the CDM check if 'snps,enable-cdm-check' exists; previously
     we skipped it if 'num-lanes' was absent (Serge Semin)

   - Allocate a 32-bit DMA-able page to be MSI target instead of using a
     driver data structure that may not be addressable with 32-bit
     address (Will McVicker)

   - Add DWC core support for more than 32 MSI interrupts (Dmitry
     Baryshkov)

  Xilinx Versal CPM PCIe controller driver:

   - Add DT binding and driver support for Versal CPM5 Gen5 Root Port
     (Bharat Kumar Gogada)"

* tag 'pci-v5.20-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (150 commits)
  PCI: imx6: Support more than Gen2 speed link mode
  PCI: imx6: Set PCIE_DBI_RO_WR_EN before writing DBI registers
  PCI: imx6: Reformat suspend callback to keep symmetric with resume
  PCI: imx6: Move the imx6_pcie_ltssm_disable() earlier
  PCI: imx6: Disable clocks in reverse order of enable
  PCI: imx6: Do not hide PHY driver callbacks and refine the error handling
  PCI: imx6: Reduce resume time by only starting link if it was up before suspend
  PCI: imx6: Mark the link down as non-fatal error
  PCI: imx6: Move regulator enable out of imx6_pcie_deassert_core_reset()
  PCI: imx6: Turn off regulator when system is in suspend mode
  PCI: imx6: Call host init function directly in resume
  PCI: imx6: Disable i.MX6QDL clock when disabling ref clocks
  PCI: imx6: Propagate .host_init() errors to caller
  PCI: imx6: Collect clock enables in imx6_pcie_clk_enable()
  PCI: imx6: Factor out ref clock disable to match enable
  PCI: imx6: Move imx6_pcie_clk_disable() earlier
  PCI: imx6: Move imx6_pcie_enable_ref_clk() earlier
  PCI: imx6: Move PHY management functions together
  PCI: imx6: Move imx6_pcie_grp_offset(), imx6_pcie_configure_type() earlier
  PCI: imx6: Convert to NOIRQ_SYSTEM_SLEEP_PM_OPS()
  ...
2022-08-04 19:30:35 -07:00
Linus Torvalds
c040862bfb Xtensa updates for v5.20
- support KCOV
 - enable ARCH_HAS_GCOV_PROFILE_ALL
 - minor ISS network driver cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEK2eFS5jlMn3N6xfYUfnMkfg/oEQFAmLsCugTHGpjbXZia2Jj
 QGdtYWlsLmNvbQAKCRBR+cyR+D+gRI9xD/9R+LcQFYoWXKJv57XAopM3q5QsR8hZ
 sQNWnErzf+LpUVCZHlniyQkywf6KpILm6lRHTd4qs/ny8B5rjnbWLD2xx8qSZ9lq
 6YT5HtimCj6qeU7eQPp4OAf9NNC6bkpYOFF0D5eU+smgS1A2PyZnYGMvXWPwUhtM
 R+z4+CIB0XHRWazNC7hrJOAmge0rWQgpiDxRQMYCKTQH1o1MZc5F0k9V/OJtVDRt
 zLiC7fMI6Uijsw9woAU9sfl4zU7FnM0S10gXtL2J/e5DEKovDegHeGrHpXyNBtCG
 9xnCXu285XKRlGDXGtO+EnSgmHmPmaIxW4F5I3uK/fCdfex4NdbuLf+WWuK2eSPM
 KDWLlWq76F9/Fdv4yPQoysUWoEXNjbpsgESITZdatyLZMZtUGE7rM4ysHOxN/VOG
 cDa1jwY9Od7Mg6HfVO1sm+8ZcY4adsMKfyUVp55H5l6Dvd44o50wF5Eblrq0ouuC
 zkBlnFdxn5CxyaMFNgaGJuAcdW5BesQdRLhmjh06uAC9WXOSmq1aGjt9IcKjBH+4
 Uf/8iiVmQtcUanFokcbNlgByIaJ7Mwik13yMY6cVk7I4+3NoI15OWIF54241gtHb
 6glbBkbTOTO3S1l1MasqAUDZjYl2yJxtckoVAREzDmMMlsYqJZ5J8UEmjJNNiqN0
 f52eQXMUFZxjuQ==
 =CLFr
 -----END PGP SIGNATURE-----

Merge tag 'xtensa-20220804' of https://github.com/jcmvbkbc/linux-xtensa

Pull xtensa updates from Max Filippov:

 - support KCOV

 - enable ARCH_HAS_GCOV_PROFILE_ALL

 - minor ISS network driver cleanups

* tag 'xtensa-20220804' of https://github.com/jcmvbkbc/linux-xtensa:
  xtensa: enable ARCH_HAS_GCOV_PROFILE_ALL
  xtensa: enable KCOV support
  xtensa: iss: fix handling error cases in iss_net_configure()
  xtensa: iss/network: provide release() callback
  xtensa: iss/network: drop 'devices' list
2022-08-04 15:35:58 -07:00
Linus Torvalds
7d9d077c78 RCU pull request for v5.20 (or whatever)
This pull request contains the following branches:
 
 doc.2022.06.21a: Documentation updates.
 
 fixes.2022.07.19a: Miscellaneous fixes.
 
 nocb.2022.07.19a: Callback-offload updates, perhaps most notably a new
 	RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to
 	be offloaded at boot time, regardless of kernel boot parameters.
 	This is useful to battery-powered systems such as ChromeOS
 	and Android.  In addition, a new RCU_NOCB_CPU_CB_BOOST kernel
 	boot parameter prevents offloaded callbacks from interfering
 	with real-time workloads and with energy-efficiency mechanisms.
 
 poll.2022.07.21a: Polled grace-period updates, perhaps most notably
 	making these APIs account for both normal and expedited grace
 	periods.
 
 rcu-tasks.2022.06.21a: Tasks RCU updates, perhaps most notably reducing
 	the CPU overhead of RCU tasks trace grace periods by more than
 	a factor of two on a system with 15,000 tasks.	The reduction
 	is expected to increase with the number of tasks, so it seems
 	reasonable to hypothesize that a system with 150,000 tasks might
 	see a 20-fold reduction in CPU overhead.
 
 torture.2022.06.21a: Torture-test updates.
 
 ctxt.2022.07.05a: Updates that merge RCU's dyntick-idle tracking into
 	context tracking, thus reducing the overhead of transitioning to
 	kernel mode from either idle or nohz_full userspace execution
 	for kernels that track context independently of RCU.  This is
 	expected to be helpful primarily for kernels built with
 	CONFIG_NO_HZ_FULL=y.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEbK7UrM+RBIrCoViJnr8S83LZ+4wFAmLgMcgTHHBhdWxtY2tA
 a2VybmVsLm9yZwAKCRCevxLzctn7jArXD/0fjbCwqpRjHVTzjMY8jN4zDkqZZD6m
 g8Fx27hZ4ToNFwRptyHwNezrNj14skjAJEXfdjaVw32W62ivXvf0HINvSzsTLCSq
 k2kWyBdXLc9CwY5p5W4smnpn5VoAScjg5PoPL59INoZ/Zziji323C7Zepl/1DYJt
 0T6bPCQjo1ZQoDUCyVpSjDmAqxnderWG0MeJVt74GkLqmnYLANg0GH8c7mH4+9LL
 kVGlLp5nlPgNJ4FEoFdMwNU8T/ETmaVld/m2dkiawjkXjJzB2XKtBigU91DDmXz5
 7DIdV4ABrxiy4kGNqtIe/jFgnKyVD7xiDpyfjd6KTeDr/rDS8u2ZH7+1iHsyz3g0
 Np/tS3vcd0KR+gI/d0eXxPbgm5sKlCmKw/nU2eArpW/+4LmVXBUfHTG9Jg+LJmBc
 JrUh6aEdIZJZHgv/nOQBNig7GJW43IG50rjuJxAuzcxiZNEG5lUSS23ysaA9CPCL
 PxRWKSxIEfK3kdmvVO5IIbKTQmIBGWlcWMTcYictFSVfBgcCXpPAksGvqA5JiUkc
 egW+xLFo/7K+E158vSKsVqlWZcEeUbsNJ88QOlpqnRgH++I2Yv/LhK41XfJfpH+Y
 ALxVaDd+mAq6v+qSHNVq9wT3ozXIPy/zK1hDlMIqx40h2YvaEsH4je+521oSoN9r
 vX60+QNxvUBLwA==
 =vUNm
 -----END PGP SIGNATURE-----

Merge tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull RCU updates from Paul McKenney:

 - Documentation updates

 - Miscellaneous fixes

 - Callback-offload updates, perhaps most notably a new
   RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to be
   offloaded at boot time, regardless of kernel boot parameters.

   This is useful to battery-powered systems such as ChromeOS and
   Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel boot
   parameter prevents offloaded callbacks from interfering with
   real-time workloads and with energy-efficiency mechanisms

 - Polled grace-period updates, perhaps most notably making these APIs
   account for both normal and expedited grace periods

 - Tasks RCU updates, perhaps most notably reducing the CPU overhead of
   RCU tasks trace grace periods by more than a factor of two on a
   system with 15,000 tasks.

   The reduction is expected to increase with the number of tasks, so it
   seems reasonable to hypothesize that a system with 150,000 tasks
   might see a 20-fold reduction in CPU overhead

 - Torture-test updates

 - Updates that merge RCU's dyntick-idle tracking into context tracking,
   thus reducing the overhead of transitioning to kernel mode from
   either idle or nohz_full userspace execution for kernels that track
   context independently of RCU.

   This is expected to be helpful primarily for kernels built with
   CONFIG_NO_HZ_FULL=y

* tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (98 commits)
  rcu: Add irqs-disabled indicator to expedited RCU CPU stall warnings
  rcu: Diagnose extended sync_rcu_do_polled_gp() loops
  rcu: Put panic_on_rcu_stall() after expedited RCU CPU stall warnings
  rcutorture: Test polled expedited grace-period primitives
  rcu: Add polled expedited grace-period primitives
  rcutorture: Verify that polled GP API sees synchronous grace periods
  rcu: Make Tiny RCU grace periods visible to polled APIs
  rcu: Make polled grace-period API account for expedited grace periods
  rcu: Switch polled grace-period APIs to ->gp_seq_polled
  rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty
  rcu/nocb: Add option to opt rcuo kthreads out of RT priority
  rcu: Add nocb_cb_kthread check to rcu_is_callbacks_kthread()
  rcu/nocb: Add an option to offload all CPUs on boot
  rcu/nocb: Fix NOCB kthreads spawn failure with rcu_nocb_rdp_deoffload() direct call
  rcu/nocb: Invert rcu_state.barrier_mutex VS hotplug lock locking order
  rcu/nocb: Add/del rdp to iterate from rcuog itself
  rcu/tree: Add comment to describe GP-done condition in fqs loop
  rcu: Initialize first_gp_fqs at declaration in rcu_gp_fqs()
  rcu/kvfree: Remove useless monitor_todo flag
  rcu: Cleanup RCU urgency state for offline CPU
  ...
2022-08-02 19:12:45 -07:00
Linus Torvalds
c013d0af81 for-5.20/block-2022-07-29
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmLko3gQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpmQaD/90NKFj4v8I456TUQyg1jimXEsL+e84E6o2
 ALWVb6JzQvlPVQXNLnK5YKIunMWOTtTMz0nyB8sVRwVJVJO0P5d7QopAkZM8fkyU
 MK5OCzoryENw4DTc2wJS4in6cSbGylIuN74wMzlf7+M67JTImfoZQhbTMcjwzZfn
 b3OlL6sID7zMXwGcuOJPZyUJICCpDhzdSF9JXqKma5PQuG2SBmQyvFxJAcsoFBPc
 YetnoRIOIN6yBvsIZaPaYq7XI9MIvF0e67EQtyCEHj4tHpyVnyDWkeObVFULsISU
 gGEKbkYPvNUzRAU5Q1NBBHh1tTfkf/MaUxTuZwoEwZ/s04IGBGMmrZGyfvdfzYo6
 M7NwSEg/TrUSNfTwn65mQi7uOXu1pGkJrqz84Flm8u9Qid9Vd7LExLG5p/ggnWdH
 5th93MDEmtEg29e9DXpEAuS5d0t3TtSvosflaKpyfNNfr+P0rWCN6GM/uW62VUTK
 ls69SQh/AQJRbg64jU4xper6WhaYtSXK7TKEnxJycoEn9gYNyCcdot2uekth0xRH
 ChHGmRlteiqe/y4uFWn/2dcxWjoleiHbFjTaiRL75WVl8wIDEjw02LGuoZ61Ss9H
 WOV+MT7KqNjBGe6lreUY+O/PO02dzmoR6heJXN19p8zr/pBuLCTGX7UpO7rzgaBR
 4N1HEozvIw==
 =celk
 -----END PGP SIGNATURE-----

Merge tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - Improve the type checking of request flags (Bart)

 - Ensure queue mapping for a single queues always picks the right queue
   (Bart)

 - Sanitize the io priority handling (Jan)

 - rq-qos race fix (Jinke)

 - Reserved tags handling improvements (John)

 - Separate memory alignment from file/disk offset aligment for O_DIRECT
   (Keith)

 - Add new ublk driver, userspace block driver using io_uring for
   communication with the userspace backend (Ming)

 - Use try_cmpxchg() to cleanup the code in various spots (Uros)

 - Finally remove bdevname() (Christoph)

 - Clean up the zoned device handling (Christoph)

 - Clean up independent access range support (Christoph)

 - Clean up and improve block sysfs handling (Christoph)

 - Clean up and improve teardown of block devices.

   This turns the usual two step process into something that is simpler
   to implement and handle in block drivers (Christoph)

 - Clean up chunk size handling (Christoph)

 - Misc cleanups and fixes (Bart, Bo, Dan, GuoYong, Jason, Keith, Liu,
   Ming, Sebastian, Yang, Ying)

* tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block: (178 commits)
  ublk_drv: fix double shift bug
  ublk_drv: make sure that correct flags(features) returned to userspace
  ublk_drv: fix error handling of ublk_add_dev
  ublk_drv: fix lockdep warning
  block: remove __blk_get_queue
  block: call blk_mq_exit_queue from disk_release for never added disks
  blk-mq: fix error handling in __blk_mq_alloc_disk
  ublk: defer disk allocation
  ublk: rewrite ublk_ctrl_get_queue_affinity to not rely on hctx->cpumask
  ublk: fold __ublk_create_dev into ublk_ctrl_add_dev
  ublk: cleanup ublk_ctrl_uring_cmd
  ublk: simplify ublk_ch_open and ublk_ch_release
  ublk: remove the empty open and release block device operations
  ublk: remove UBLK_IO_F_PREFLUSH
  ublk: add a MAINTAINERS entry
  block: don't allow the same type rq_qos add more than once
  mmc: fix disk/queue leak in case of adding disk failure
  ublk_drv: fix an IS_ERR() vs NULL check
  ublk: remove UBLK_IO_F_INTEGRITY
  ublk_drv: remove unneeded semicolon
  ...
2022-08-02 13:46:35 -07:00
Linus Torvalds
9de1f9c8ca Updates for interrupt core and drivers:
core:
    - Fix a few inconsistencies between UP and SMP vs. interrupt affinities
    - Small updates and cleanups all over the place
 
  drivers:
    - New driver for the LoongArch interrupt controller
    - New driver for the Renesas RZ/G2L interrupt controller
 
    - Hotpath optimization for SiFive PLIC
    - Workaround for broken PLIC edge triggered interrupts
 
    - Simall cleanups and improvements as usual
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmLn5agTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoV2HD/4u0+09Fd8Awt1Knnb4CInmwFihZ/bu
 EiS1Air+MEJ/fyFb5sT/Dn8YdUWYA6a3ifpLMGBwrKCcb5pMwPEtI8uqjSmtgsN/
 2Z4o3N5v6EgM25CtrHNBrXK0E9Rz5Py49gm5p3K7+h4g63z9JwrM4G0Bvr8+krLS
 EV9IZU6kVmGC6gnG/MspkArsLk1rCM0PU0SJ2lEPsWd1fjhVSDfunvy/qnnzXRzz
 wjrcAf+a2Kgb1TMnpL6tx9d2Xx8KrKfODZTdOmPHrdv58F0EbJzapJnAVkYZDPtR
 LE2kQc2Qhdawx0kgNNNhvu9P6oZtpnK9N7KAhDQdw17sgrRygINjAMSEe2RykYL1
 lK+lJOIzfyd2JkEuC/8w1ZezL88S0EaTNawrkxjJ8L3fa7WDbwilCC+1w95QydCv
 sQB137OaLKgWetcRsht9PLWFb4ujkWzxoPf2cPPsm81EzCicNtBuNPLReBTcNrWJ
 X2VPpbaqRK8t8bnkXRqhahbq7f8c86feoICHfA4c7T4eZUp/Oq6T8aNvf6WPgjae
 I2/FO6kxZj3CQqFkhJGhiZRtGZdx6HLCsL84A+2Ktsra+D8+/qecZCnkHYtz0Vo6
 aFuGg+Wj+zuc2QfdaWwG8Dh5dijbxgHGHhzbh9znsWzytN9gfoBxuvBejf65i6sC
 In63mEkv35ttfA==
 =OnhF
 -----END PGP SIGNATURE-----

Merge tag 'irq-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "Updates for interrupt core and drivers:

  Core:

   - Fix a few inconsistencies between UP and SMP vs interrupt
     affinities

   - Small updates and cleanups all over the place

  New drivers:

   - LoongArch interrupt controller

   - Renesas RZ/G2L interrupt controller

  Updates:

   - Hotpath optimization for SiFive PLIC

   - Workaround for broken PLIC edge triggered interrupts

   - Simall cleanups and improvements as usual"

* tag 'irq-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  irqchip/mmp: Declare init functions in common header file
  irqchip/mips-gic: Check the return value of ioremap() in gic_of_init()
  genirq: Use for_each_action_of_desc in actions_show()
  irqchip / ACPI: Introduce ACPI_IRQ_MODEL_LPIC for LoongArch
  irqchip: Add LoongArch CPU interrupt controller support
  irqchip: Add Loongson Extended I/O interrupt controller support
  irqchip/loongson-liointc: Add ACPI init support
  irqchip/loongson-pch-msi: Add ACPI init support
  irqchip/loongson-pch-pic: Add ACPI init support
  irqchip: Add Loongson PCH LPC controller support
  LoongArch: Prepare to support multiple pch-pic and pch-msi irqdomain
  LoongArch: Use ACPI_GENERIC_GSI for gsi handling
  genirq/generic_chip: Export irq_unmap_generic_chip
  ACPI: irq: Allow acpi_gsi_to_irq() to have an arch-specific fallback
  APCI: irq: Add support for multiple GSI domains
  LoongArch: Provisionally add ACPICA data structures
  irqdomain: Use hwirq_max instead of revmap_size for NOMAP domains
  irqdomain: Report irq number for NOMAP domains
  irqchip/gic-v3: Fix comment typo
  dt-bindings: interrupt-controller: renesas,rzg2l-irqc: Document RZ/V2L SoC
  ...
2022-08-01 12:48:15 -07:00
Stafford Horne
abb4970ac3 PCI: Move isa_dma_bridge_buggy out of asm/dma.h
The isa_dma_bridge_buggy symbol is only used for x86_32, and only x86_32
platforms or quirks ever set it.

Add a new linux/isa-dma.h header that #defines isa_dma_bridge_buggy to 0
except on x86_32, where we keep it as a variable, and remove all the arch-
specific definitions.

[bhelgaas: commit log]
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/r/20220722214944.831438-3-shorne@gmail.com
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2022-07-22 17:24:47 -05:00
Stafford Horne
ae85b23c65 PCI: Remove pci_get_legacy_ide_irq() and asm-generic/pci.h
pci_get_legacy_ide_irq() is only used on platforms that support PNP, so
many architectures define it but never use it.  Replace uses of it with
ATA_PRIMARY_IRQ() and ATA_SECONDARY_IRQ(), which provide the same
functionality.

Since pci_get_legacy_ide_irq() is no longer used, remove all the
architecture-specific definitions of it as well as asm-generic/pci.h, which
only provides pci_get_legacy_ide_irq()

[bhelgaas: commit log]
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20220722214944.831438-2-shorne@gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-22 17:23:45 -05:00
Mike Rapoport
64c5ed22d6 xtensa: drop definition of PGD_ORDER
This is the order of the page table allocation, not the order of a PGD. 
Since its always hardwired to 0, simply drop it.

Link: https://lkml.kernel.org/r/20220703141203.147893-15-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Helge Deller <deller@gmx.de>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Xuerui Wang <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:44 -07:00
Anshuman Khandual
3d923c5f1e mm/mmap: drop ARCH_HAS_VM_GET_PAGE_PROT
Now all the platforms enable ARCH_HAS_GET_PAGE_PROT.  They define and
export own vm_get_page_prot() whether custom or standard
DECLARE_VM_GET_PAGE_PROT.  Hence there is no need for default generic
fallback for vm_get_page_prot().  Just drop this fallback and also
ARCH_HAS_GET_PAGE_PROT mechanism.

Link: https://lkml.kernel.org/r/20220711070600.2378316-27-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:41 -07:00
Anshuman Khandual
2de9eae10d xtensa/mm: enable ARCH_HAS_VM_GET_PAGE_PROT
This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports
standard vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT,
which looks up a private and static protection_map[] array.  Subsequently
all __SXXX and __PXXX macros can be dropped which are no longer needed.

Link: https://lkml.kernel.org/r/20220711070600.2378316-12-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Guo Ren <guoren@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:39 -07:00
Max Filippov
0847d167d0 xtensa: enable ARCH_HAS_GCOV_PROFILE_ALL
Select ARCH_HAS_GCOV_PROFILE_ALL and set GCOV_PROFILE = n inside
arch/xtensa/boot/lib.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-07-14 00:54:47 -07:00
Max Filippov
c49731a04e xtensa: enable KCOV support
Select ARCH_HAS_KCOV and set KCOV_INSTRUMENT = n inside
arch/xtensa/boot/lib.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-07-14 00:54:46 -07:00
Yang Yingliang
628ccfc8f5 xtensa: iss: fix handling error cases in iss_net_configure()
The 'pdev' and 'netdev' need to be released in error cases of
iss_net_configure().

Change the return type of iss_net_configure() to void, because it's
not used.

Fixes: 7282bee787 ("[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 8")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-07-14 00:54:31 -07:00
Max Filippov
8864fb8359 xtensa: iss/network: provide release() callback
Provide release() callback for the platform device embedded into struct
iss_net_private and registered in the iss_net_configure so that
platform_device_unregister could be called for it.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-07-14 00:54:31 -07:00
Max Filippov
0391334907 xtensa: iss/network: drop 'devices' list
There are two per-device lists in the ISS network driver: command line
parameters list and iss_net_private object list. The latter is only used
for duplicate checking in the function iss_net_setup where the former
should have been used.
Drop iss_net_private object list and associated code and use command
line parameters list in the iss_net_setup instead.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-07-14 00:54:31 -07:00
Samuel Holland
4d0b829881 genirq: Return a const cpumask from irq_data_get_affinity_mask
Now that the irq_data_update_affinity helper exists, enforce its use
by returning a a const cpumask from irq_data_get_affinity_mask.

Since the previous commit already updated places that needed to call
irq_data_update_affinity, this commit updates the remaining code that
either did not modify the cpumask or immediately passed the modified
mask to irq_set_affinity.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220701200056.46555-8-samuel@sholland.org
2022-07-07 09:38:04 +01:00
Frederic Weisbecker
24a9c54182 context_tracking: Split user tracking Kconfig
Context tracking is going to be used not only to track user transitions
but also idle/IRQs/NMIs. The user tracking part will then become a
separate feature. Prepare Kconfig for that.

[ frederic: Apply Max Filippov feedback. ]

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Uladzislau Rezki <uladzislau.rezki@sony.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Yu Liao <liaoyu15@huawei.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Paul Gortmaker<paul.gortmaker@windriver.com>
Cc: Alex Belits <abelits@marvell.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
2022-06-29 17:04:09 -07:00
Frederic Weisbecker
f163f0302a context_tracking: Rename context_tracking_user_enter/exit() to user_enter/exit_callable()
context_tracking_user_enter() and context_tracking_user_exit() are
ASM callable versions of user_enter() and user_exit() for architectures
that didn't manage to check the context tracking static key from ASM.
Change those function names to better reflect their purpose.

[ frederic: Apply Max Filippov feedback. ]

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Uladzislau Rezki <uladzislau.rezki@sony.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Yu Liao <liaoyu15@huawei.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Paul Gortmaker<paul.gortmaker@windriver.com>
Cc: Alex Belits <abelits@marvell.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
2022-06-29 17:03:27 -07:00
Christoph Hellwig
8b9ab62662 block: remove blk_cleanup_disk
blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-28 06:33:15 -06:00
Arnd Bergmann
4313a24985 arch/*/: remove CONFIG_VIRT_TO_BUS
All architecture-independent users of virt_to_bus() and bus_to_virt()
have been fixed to use the dma mapping interfaces or have been
removed now.  This means the definitions on most architectures, and the
CONFIG_VIRT_TO_BUS symbol are now obsolete and can be removed.

The only exceptions to this are a few network and scsi drivers for m68k
Amiga and VME machines and ppc32 Macintosh. These drivers work correctly
with the old interfaces and are probably not worth changing.

On alpha and parisc, virt_to_bus() were still used in asm/floppy.h.
alpha can use isa_virt_to_bus() like x86 does, and parisc can just
open-code the virt_to_phys() here, as this is architecture specific
code.

I tried updating the bus-virt-phys-mapping.rst documentation, which
started as an email from Linus to explain some details of the Linux-2.0
driver interfaces. The bits about virt_to_bus() were declared obsolete
backin 2000, and the rest is not all that relevant any more, so in the
end I just decided to remove the file completely.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-06-28 13:20:21 +02:00
akpm
46a3b11253 Merge branch 'master' into mm-stable 2022-06-27 10:31:34 -07:00
Max Filippov
a2d9b75b19 xtensa: change '.bss' to '.section .bss'
For some reason (ancient assembler?) the following build error is
reported by the kisskb:

  kisskb/src/arch/xtensa/kernel/entry.S: Error: unknown pseudo-op: `.bss':
  => 2176

Change abbreviated '.bss' to the full '.section .bss, "aw"' to fix this
error.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-06-20 02:50:34 -07:00
Liang He
173940b3ae xtensa: xtfpga: Fix refcount leak bug in setup
In machine_setup(), of_find_compatible_node() will return a node
pointer with refcount incremented. We should use of_node_put() when
it is not used anymore.

Cc: stable@vger.kernel.org
Signed-off-by: Liang He <windhl@126.com>
Message-Id: <20220617115323.4046905-1-windhl@126.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-06-18 14:47:41 -07:00
Liang He
a0117dc956 xtensa: Fix refcount leak bug in time.c
In calibrate_ccount(), of_find_compatible_node() will return a node
pointer with refcount incremented. We should use of_node_put() when
it is not used anymore.

Cc: stable@vger.kernel.org
Signed-off-by: Liang He <windhl@126.com>
Message-Id: <20220617124432.4049006-1-windhl@126.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-06-18 14:46:59 -07:00
Peter Xu
d92725256b mm: avoid unnecessary page fault retires on shared memory types
I observed that for each of the shared file-backed page faults, we're very
likely to retry one more time for the 1st write fault upon no page.  It's
because we'll need to release the mmap lock for dirty rate limit purpose
with balance_dirty_pages_ratelimited() (in fault_dirty_shared_page()).

Then after that throttling we return VM_FAULT_RETRY.

We did that probably because VM_FAULT_RETRY is the only way we can return
to the fault handler at that time telling it we've released the mmap lock.

However that's not ideal because it's very likely the fault does not need
to be retried at all since the pgtable was well installed before the
throttling, so the next continuous fault (including taking mmap read lock,
walk the pgtable, etc.) could be in most cases unnecessary.

It's not only slowing down page faults for shared file-backed, but also add
more mmap lock contention which is in most cases not needed at all.

To observe this, one could try to write to some shmem page and look at
"pgfault" value in /proc/vmstat, then we should expect 2 counts for each
shmem write simply because we retried, and vm event "pgfault" will capture
that.

To make it more efficient, add a new VM_FAULT_COMPLETED return code just to
show that we've completed the whole fault and released the lock.  It's also
a hint that we should very possibly not need another fault immediately on
this page because we've just completed it.

This patch provides a ~12% perf boost on my aarch64 test VM with a simple
program sequentially dirtying 400MB shmem file being mmap()ed and these are
the time it needs:

  Before: 650.980 ms (+-1.94%)
  After:  569.396 ms (+-1.38%)

I believe it could help more than that.

We need some special care on GUP and the s390 pgfault handler (for gmap
code before returning from pgfault), the rest changes in the page fault
handlers should be relatively straightforward.

Another thing to mention is that mm_account_fault() does take this new
fault as a generic fault to be accounted, unlike VM_FAULT_RETRY.

I explicitly didn't touch hmm_vma_fault() and break_ksm() because they do
not handle VM_FAULT_RETRY even with existing code, so I'm literally keeping
them as-is.

Link: https://lkml.kernel.org/r/20220530183450.42886-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vineet Gupta <vgupta@kernel.org>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>	[arm part]
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Stafford Horne <shorne@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Will Deacon <will@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Rich Felker <dalias@libc.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Helge Deller <deller@gmx.de>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-06-16 19:48:27 -07:00
Linus Torvalds
67850b7bdc While looking at the ptrace problems with PREEMPT_RT and the problems
of Peter Zijlstra was encountering with ptrace in his freezer rewrite
 I identified some cleanups to ptrace_stop that make sense on their own
 and move make resolving the other problems much simpler.
 
 The biggest issue is the habbit of the ptrace code to change task->__state
 from the tracer to suppress TASK_WAKEKILL from waking up the tracee.  No
 other code in the kernel does that and it is straight forward to update
 signal_wake_up and friends to make that unnecessary.
 
 Peter's task freezer sets frozen tasks to a new state TASK_FROZEN and
 then it stores them by calling "wake_up_state(t, TASK_FROZEN)" relying
 on the fact that all stopped states except the special stop states can
 tolerate spurious wake up and recover their state.
 
 The state of stopped and traced tasked is changed to be stored in
 task->jobctl as well as in task->__state.  This makes it possible for
 the freezer to recover tasks in these special states, as well as
 serving as a general cleanup.  With a little more work in that
 direction I believe TASK_STOPPED can learn to tolerate spurious wake
 ups and become an ordinary stop state.
 
 The TASK_TRACED state has to remain a special state as the registers for
 a process are only reliably available when the process is stopped in
 the scheduler.  Fundamentally ptrace needs acess to the saved
 register values of a task.
 
 There are bunch of semi-random ptrace related cleanups that were found
 while looking at these issues.
 
 One cleanup that deserves to be called out is from commit 57b6de08b5
 ("ptrace: Admit ptrace_stop can generate spuriuos SIGTRAPs").  This
 makes a change that is technically user space visible, in the handling
 of what happens to a tracee when a tracer dies unexpectedly.
 According to our testing and our understanding of userspace nothing
 cares that spurious SIGTRAPs can be generated in that case.
 
 The entire discussion can be found at:
   https://lkml.kernel.org/r/87a6bv6dl6.fsf_-_@email.froward.int.ebiederm.org
 
 Eric W. Biederman (11):
       signal: Rename send_signal send_signal_locked
       signal: Replace __group_send_sig_info with send_signal_locked
       ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP
       ptrace/xtensa: Replace PT_SINGLESTEP with TIF_SINGLESTEP
       ptrace: Remove arch_ptrace_attach
       signal: Use lockdep_assert_held instead of assert_spin_locked
       ptrace: Reimplement PTRACE_KILL by always sending SIGKILL
       ptrace: Document that wait_task_inactive can't fail
       ptrace: Admit ptrace_stop can generate spuriuos SIGTRAPs
       ptrace: Don't change __state
       ptrace: Always take siglock in ptrace_resume
 
 Peter Zijlstra (1):
       sched,signal,ptrace: Rework TASK_TRACED, TASK_STOPPED state
 
  arch/ia64/include/asm/ptrace.h    |   4 --
  arch/ia64/kernel/ptrace.c         |  57 ----------------
  arch/um/include/asm/thread_info.h |   2 +
  arch/um/kernel/exec.c             |   2 +-
  arch/um/kernel/process.c          |   2 +-
  arch/um/kernel/ptrace.c           |   8 +--
  arch/um/kernel/signal.c           |   4 +-
  arch/x86/kernel/step.c            |   3 +-
  arch/xtensa/kernel/ptrace.c       |   4 +-
  arch/xtensa/kernel/signal.c       |   4 +-
  drivers/tty/tty_jobctrl.c         |   4 +-
  include/linux/ptrace.h            |   7 --
  include/linux/sched.h             |  10 ++-
  include/linux/sched/jobctl.h      |   8 +++
  include/linux/sched/signal.h      |  20 ++++--
  include/linux/signal.h            |   3 +-
  kernel/ptrace.c                   |  87 ++++++++---------------
  kernel/sched/core.c               |   5 +-
  kernel/signal.c                   | 140 +++++++++++++++++---------------------
  kernel/time/posix-cpu-timers.c    |   6 +-
  20 files changed, 140 insertions(+), 240 deletions(-)
 
 Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEgjlraLDcwBA2B+6cC/v6Eiajj0AFAmKaXaYACgkQC/v6Eiaj
 j0CgoA/+JncSQ6PY2D5Jh1apvHzmnRsFXzr3DRvtv/CVx4oIebOXRQFyVDeD5tRn
 TmMgB29HpBlHRDLojlmlZRGAld1HR/aPEW9j8W1D3Sy/ZFO5L8lQitv9aDHO9Ntw
 4lZvlhS1M0KhATudVVBqSPixiG6CnV5SsGmixqdOyg7xcXSY6G1l2nB7Zk9I3Tat
 ZlmhuZ6R5Z5qsm4MEq0vUSrnsHiGxYrpk6uQOaVz8Wkv8ZFmbutt6XgxF0tsyZNn
 mHSmWSiZzIgBjTlaibEmxi8urYJTPj3vGBeJQVYHblFwLFi6+Oy7bDxQbWjQvaZh
 DsgWPScfBF4Jm0+8hhCiSYpvPp8XnZuklb4LNCeok/VFr+KfSmpJTIhn00kagQ1u
 vxQDqLws8YLW4qsfGydfx9uUIFCbQE/V2VDYk5J3Re3gkUNDOOR1A56hPniKv6VB
 2aqGO2Fl0RdBbUa3JF+XI5Pwq5y1WrqR93EUvj+5+u5W9rZL/8WLBHBMEz6gbmfD
 DhwFE0y8TG2WRlWJVEDRId+5zo3di/YvasH0vJZ5HbrxhS2RE/yIGAd+kKGx/lZO
 qWDJC7IHvFJ7Mw5KugacyF0SHeNdloyBM7KZW6HeXmgKn9IMJBpmwib92uUkRZJx
 D8j/bHHqD/zsgQ39nO+c4M0MmhO/DsPLG/dnGKrRCu7v1tmEnkY=
 =ZUuO
 -----END PGP SIGNATURE-----

Merge tag 'ptrace_stop-cleanup-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull ptrace_stop cleanups from Eric Biederman:
 "While looking at the ptrace problems with PREEMPT_RT and the problems
  Peter Zijlstra was encountering with ptrace in his freezer rewrite I
  identified some cleanups to ptrace_stop that make sense on their own
  and move make resolving the other problems much simpler.

  The biggest issue is the habit of the ptrace code to change
  task->__state from the tracer to suppress TASK_WAKEKILL from waking up
  the tracee. No other code in the kernel does that and it is straight
  forward to update signal_wake_up and friends to make that unnecessary.

  Peter's task freezer sets frozen tasks to a new state TASK_FROZEN and
  then it stores them by calling "wake_up_state(t, TASK_FROZEN)" relying
  on the fact that all stopped states except the special stop states can
  tolerate spurious wake up and recover their state.

  The state of stopped and traced tasked is changed to be stored in
  task->jobctl as well as in task->__state. This makes it possible for
  the freezer to recover tasks in these special states, as well as
  serving as a general cleanup. With a little more work in that
  direction I believe TASK_STOPPED can learn to tolerate spurious wake
  ups and become an ordinary stop state.

  The TASK_TRACED state has to remain a special state as the registers
  for a process are only reliably available when the process is stopped
  in the scheduler. Fundamentally ptrace needs acess to the saved
  register values of a task.

  There are bunch of semi-random ptrace related cleanups that were found
  while looking at these issues.

  One cleanup that deserves to be called out is from commit 57b6de08b5
  ("ptrace: Admit ptrace_stop can generate spuriuos SIGTRAPs"). This
  makes a change that is technically user space visible, in the handling
  of what happens to a tracee when a tracer dies unexpectedly. According
  to our testing and our understanding of userspace nothing cares that
  spurious SIGTRAPs can be generated in that case"

* tag 'ptrace_stop-cleanup-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  sched,signal,ptrace: Rework TASK_TRACED, TASK_STOPPED state
  ptrace: Always take siglock in ptrace_resume
  ptrace: Don't change __state
  ptrace: Admit ptrace_stop can generate spuriuos SIGTRAPs
  ptrace: Document that wait_task_inactive can't fail
  ptrace: Reimplement PTRACE_KILL by always sending SIGKILL
  signal: Use lockdep_assert_held instead of assert_spin_locked
  ptrace: Remove arch_ptrace_attach
  ptrace/xtensa: Replace PT_SINGLESTEP with TIF_SINGLESTEP
  ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP
  signal: Replace __group_send_sig_info with send_signal_locked
  signal: Rename send_signal send_signal_locked
2022-06-03 16:13:25 -07:00
Linus Torvalds
1ec6574a3c This set of changes updates init and user mode helper tasks to be
ordinary user mode tasks.
 
 In commit 40966e316f ("kthread: Ensure struct kthread is present for
 all kthreads") caused init and the user mode helper threads that call
 kernel_execve to have struct kthread allocated for them.  This struct
 kthread going away during execve in turned made a use after free of
 struct kthread possible.
 
 The commit 343f4c49f2 ("kthread: Don't allocate kthread_struct for
 init and umh") is enough to fix the use after free and is simple enough
 to be backportable.
 
 The rest of the changes pass struct kernel_clone_args to clean things
 up and cause the code to make sense.
 
 In making init and the user mode helpers tasks purely user mode tasks
 I ran into two complications.  The function task_tick_numa was
 detecting tasks without an mm by testing for the presence of
 PF_KTHREAD.  The initramfs code in populate_initrd_image was using
 flush_delayed_fput to ensuere the closing of all it's file descriptors
 was complete, and flush_delayed_fput does not work in a userspace thread.
 
 I have looked and looked and more complications and in my code review
 I have not found any, and neither has anyone else with the code sitting
 in linux-next.
 
 Link: https://lkml.kernel.org/r/87mtfu4up3.fsf@email.froward.int.ebiederm.org
 
 Eric W. Biederman (8):
       kthread: Don't allocate kthread_struct for init and umh
       fork: Pass struct kernel_clone_args into copy_thread
       fork: Explicity test for idle tasks in copy_thread
       fork: Generalize PF_IO_WORKER handling
       init: Deal with the init process being a user mode process
       fork: Explicitly set PF_KTHREAD
       fork: Stop allowing kthreads to call execve
       sched: Update task_tick_numa to ignore tasks without an mm
 
  arch/alpha/kernel/process.c      | 13 ++++++------
  arch/arc/kernel/process.c        | 13 ++++++------
  arch/arm/kernel/process.c        | 12 ++++++-----
  arch/arm64/kernel/process.c      | 12 ++++++-----
  arch/csky/kernel/process.c       | 15 ++++++-------
  arch/h8300/kernel/process.c      | 10 ++++-----
  arch/hexagon/kernel/process.c    | 12 ++++++-----
  arch/ia64/kernel/process.c       | 15 +++++++------
  arch/m68k/kernel/process.c       | 12 ++++++-----
  arch/microblaze/kernel/process.c | 12 ++++++-----
  arch/mips/kernel/process.c       | 13 ++++++------
  arch/nios2/kernel/process.c      | 12 ++++++-----
  arch/openrisc/kernel/process.c   | 12 ++++++-----
  arch/parisc/kernel/process.c     | 18 +++++++++-------
  arch/powerpc/kernel/process.c    | 15 +++++++------
  arch/riscv/kernel/process.c      | 12 ++++++-----
  arch/s390/kernel/process.c       | 12 ++++++-----
  arch/sh/kernel/process_32.c      | 12 ++++++-----
  arch/sparc/kernel/process_32.c   | 12 ++++++-----
  arch/sparc/kernel/process_64.c   | 12 ++++++-----
  arch/um/kernel/process.c         | 15 +++++++------
  arch/x86/include/asm/fpu/sched.h |  2 +-
  arch/x86/include/asm/switch_to.h |  8 +++----
  arch/x86/kernel/fpu/core.c       |  4 ++--
  arch/x86/kernel/process.c        | 18 +++++++++-------
  arch/xtensa/kernel/process.c     | 17 ++++++++-------
  fs/exec.c                        |  8 ++++---
  include/linux/sched/task.h       |  8 +++++--
  init/initramfs.c                 |  2 ++
  init/main.c                      |  2 +-
  kernel/fork.c                    | 46 +++++++++++++++++++++++++++++++++-------
  kernel/sched/fair.c              |  2 +-
  kernel/umh.c                     |  6 +++---
  33 files changed, 234 insertions(+), 160 deletions(-)
 
 Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEgjlraLDcwBA2B+6cC/v6Eiajj0AFAmKaR/MACgkQC/v6Eiaj
 j0Aayg/7Bx66872d9c6igkJ+MPCTuh+v9QKCGwiYEmiU4Q5sVAFB0HPJO27qC14u
 630X0RFNZTkPzNNEJNIW4kw6Dj8s8YRKf+FgQAVt4SzdRwT7eIPDjk1nGraopPJ3
 O04pjvuTmUyidyViRyFcf2ptx/pnkrwP8jUSc+bGTgfASAKAgAokqKE5ecjewbBc
 Y/EAkQ6QW7KxPjeSmpAHwI+t3BpBev9WEC4PbhRhsBCQFO2+PJiklvqdhVNBnIjv
 qUezll/1xv9UYgniB15Q4Nb722SmnWSU3r8as1eFPugzTHizKhufrrpyP+KMK1A0
 tdtEJNs5t2DZF7ZbGTFSPqJWmyTYLrghZdO+lOmnaSjHxK4Nda1d4NzbefJ0u+FE
 tutewowvHtBX6AFIbx+H3O+DOJM2IgNMf+ReQDU/TyNyVf3wBrTbsr9cLxypIJIp
 zze8npoLMlB7B4yxVo5ES5e63EXfi3iHl0L3/1EhoGwriRz1kWgVLUX/VZOUpscL
 RkJHsW6bT8sqxPWAA5kyWjEN+wNR2PxbXi8OE4arT0uJrEBMUgDCzydzOv5tJB00
 mSQdytxH9LVdsmxBKAOBp5X6WOLGA4yb1cZ6E/mEhlqXMpBDF1DaMfwbWqxSYi4q
 sp5zU3SBAW0qceiZSsWZXInfbjrcQXNV/DkDRDO9OmzEZP4m1j0=
 =x6fy
 -----END PGP SIGNATURE-----

Merge tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull kthread updates from Eric Biederman:
 "This updates init and user mode helper tasks to be ordinary user mode
  tasks.

  Commit 40966e316f ("kthread: Ensure struct kthread is present for
  all kthreads") caused init and the user mode helper threads that call
  kernel_execve to have struct kthread allocated for them. This struct
  kthread going away during execve in turned made a use after free of
  struct kthread possible.

  Here, commit 343f4c49f2 ("kthread: Don't allocate kthread_struct for
  init and umh") is enough to fix the use after free and is simple
  enough to be backportable.

  The rest of the changes pass struct kernel_clone_args to clean things
  up and cause the code to make sense.

  In making init and the user mode helpers tasks purely user mode tasks
  I ran into two complications. The function task_tick_numa was
  detecting tasks without an mm by testing for the presence of
  PF_KTHREAD. The initramfs code in populate_initrd_image was using
  flush_delayed_fput to ensuere the closing of all it's file descriptors
  was complete, and flush_delayed_fput does not work in a userspace
  thread.

  I have looked and looked and more complications and in my code review
  I have not found any, and neither has anyone else with the code
  sitting in linux-next"

* tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  sched: Update task_tick_numa to ignore tasks without an mm
  fork: Stop allowing kthreads to call execve
  fork: Explicitly set PF_KTHREAD
  init: Deal with the init process being a user mode process
  fork: Generalize PF_IO_WORKER handling
  fork: Explicity test for idle tasks in copy_thread
  fork: Pass struct kernel_clone_args into copy_thread
  kthread: Don't allocate kthread_struct for init and umh
2022-06-03 16:03:05 -07:00
Linus Torvalds
ac2ab99072 Random number generator updates for Linux 5.19-rc1.
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEq5lC5tSkz8NBJiCnSfxwEqXeA64FAmKKpM8ACgkQSfxwEqXe
 A6726w/+OJimGd4arvpSmdn+vxepSyDLgKfwM0x5zprRVd16xg8CjJr4eMonTesq
 YvtJRqpetb53MB+sMhutlvQqQzrjtf2MBkgPwF4I2gUrk7vLD45Q+AGdGhi/rUwz
 wHGA7xg1FHLHia2M/9idSqi8QlZmUP4u4l5ZnMyTUHiwvRD6XOrWKfqvUSawNzyh
 hCWlTUxDrjizsW5YpsJX/MkRadSC8loJEk5ByZebow6nRPfurJvqfrcOMgHyNrbY
 pOZ/CGPxcetMqotL2TuuJt5wKmenqYhIWGAp3YM2SWWgU2ueBZekW8AYeMfgUcvh
 LWV93RpSuAnE5wsdjIULvjFnEDJBf8ihfMnMrd9G5QjQu44tuKWfY2MghLSpYzaR
 V6UFbRmhrqhqiStHQXOvk1oqxtpbHlc9zzJLmvPmDJcbvzXQ9Opk5GVXAmdtnHnj
 M/ty3wGWxucY6mHqT8MkCShSSslbgEtc1pEIWHdrUgnaiSVoCVBEO+9LqLbjvOTm
 XA/6YtoiCE5FasK51pir1zVb2GORQn0v8HnuAOsusD/iPAlRQ/G5jZkaXbwRQI6j
 atYL1svqvSKn5POnzqAlMUXfMUr19K5xqJdp7i6qmlO1Vq6Z+tWbCQgD1JV+Wjkb
 CMyvXomFCFu4aYKGRE2SBRnWLRghG3kYHqEQ15yTPMQerxbUDNg=
 =SUr3
 -----END PGP SIGNATURE-----

Merge tag 'random-5.19-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random

Pull random number generator updates from Jason Donenfeld:
 "These updates continue to refine the work began in 5.17 and 5.18 of
  modernizing the RNG's crypto and streamlining and documenting its
  code.

  New for 5.19, the updates aim to improve entropy collection methods
  and make some initial decisions regarding the "premature next" problem
  and our threat model. The cloc utility now reports that random.c is
  931 lines of code and 466 lines of comments, not that basic metrics
  like that mean all that much, but at the very least it tells you that
  this is very much a manageable driver now.

  Here's a summary of the various updates:

   - The random_get_entropy() function now always returns something at
     least minimally useful. This is the primary entropy source in most
     collectors, which in the best case expands to something like RDTSC,
     but prior to this change, in the worst case it would just return 0,
     contributing nothing. For 5.19, additional architectures are wired
     up, and architectures that are entirely missing a cycle counter now
     have a generic fallback path, which uses the highest resolution
     clock available from the timekeeping subsystem.

     Some of those clocks can actually be quite good, despite the CPU
     not having a cycle counter of its own, and going off-core for a
     stamp is generally thought to increase jitter, something positive
     from the perspective of entropy gathering. Done very early on in
     the development cycle, this has been sitting in next getting some
     testing for a while now and has relevant acks from the archs, so it
     should be pretty well tested and fine, but is nonetheless the thing
     I'll be keeping my eye on most closely.

   - Of particular note with the random_get_entropy() improvements is
     MIPS, which, on CPUs that lack the c0 count register, will now
     combine the high-speed but short-cycle c0 random register with the
     lower-speed but long-cycle generic fallback path.

   - With random_get_entropy() now always returning something useful,
     the interrupt handler now collects entropy in a consistent
     construction.

   - Rather than comparing two samples of random_get_entropy() for the
     jitter dance, the algorithm now tests many samples, and uses the
     amount of differing ones to determine whether or not jitter entropy
     is usable and how laborious it must be. The problem with comparing
     only two samples was that if the cycle counter was extremely slow,
     but just so happened to be on the cusp of a change, the slowness
     wouldn't be detected. Taking many samples fixes that to some
     degree.

     This, combined with the other improvements to random_get_entropy(),
     should make future unification of /dev/random and /dev/urandom
     maybe more possible. At the very least, were we to attempt it again
     today (we're not), it wouldn't break any of Guenter's test rigs
     that broke when we tried it with 5.18. So, not today, but perhaps
     down the road, that's something we can revisit.

   - We attempt to reseed the RNG immediately upon waking up from system
     suspend or hibernation, making use of the various timestamps about
     suspend time and such available, as well as the usual inputs such
     as RDRAND when available.

   - Batched randomness now falls back to ordinary randomness before the
     RNG is initialized. This provides more consistent guarantees to the
     types of random numbers being returned by the various accessors.

   - The "pre-init injection" code is now gone for good. I suspect you
     in particular will be happy to read that, as I recall you
     expressing your distaste for it a few months ago. Instead, to avoid
     a "premature first" issue, while still allowing for maximal amount
     of entropy availability during system boot, the first 128 bits of
     estimated entropy are used immediately as it arrives, with the next
     128 bits being buffered. And, as before, after the RNG has been
     fully initialized, it winds up reseeding anyway a few seconds later
     in most cases. This resulted in a pretty big simplification of the
     initialization code and let us remove various ad-hoc mechanisms
     like the ugly crng_pre_init_inject().

   - The RNG no longer pretends to handle the "premature next" security
     model, something that various academics and other RNG designs have
     tried to care about in the past. After an interesting mailing list
     thread, these issues are thought to be a) mainly academic and not
     practical at all, and b) actively harming the real security of the
     RNG by delaying new entropy additions after a potential compromise,
     making a potentially bad situation even worse. As well, in the
     first place, our RNG never even properly handled the premature next
     issue, so removing an incomplete solution to a fake problem was
     particularly nice.

     This allowed for numerous other simplifications in the code, which
     is a lot cleaner as a consequence. If you didn't see it before,
     https://lore.kernel.org/lkml/YmlMGx6+uigkGiZ0@zx2c4.com/ may be a
     thread worth skimming through.

   - While the interrupt handler received a separate code path years ago
     that avoids locks by using per-cpu data structures and a faster
     mixing algorithm, in order to reduce interrupt latency, input and
     disk events that are triggered in hardirq handlers were still
     hitting locks and more expensive algorithms. Those are now
     redirected to use the faster per-cpu data structures.

   - Rather than having the fake-crypto almost-siphash-based random32
     implementation be used right and left, and in many places where
     cryptographically secure randomness is desirable, the batched
     entropy code is now fast enough to replace that.

   - As usual, numerous code quality and documentation cleanups. For
     example, the initialization state machine now uses enum symbolic
     constants instead of just hard coding numbers everywhere.

   - Since the RNG initializes once, and then is always initialized
     thereafter, a pretty heavy amount of code used during that
     initialization is never used again. It is now completely cordoned
     off using static branches and it winds up in the .text.unlikely
     section so that it doesn't reduce cache compactness after the RNG
     is ready.

   - A variety of functions meant for waiting on the RNG to be
     initialized were only used by vsprintf, and in not a particularly
     optimal way. Replacing that usage with a more ordinary setup made
     it possible to remove those functions.

   - A cleanup of how we warn userspace about the use of uninitialized
     /dev/urandom and uninitialized get_random_bytes() usage.
     Interestingly, with the change you merged for 5.18 that attempts to
     use jitter (but does not block if it can't), the majority of users
     should never see those warnings for /dev/urandom at all now, and
     the one for in-kernel usage is mainly a debug thing.

   - The file_operations struct for /dev/[u]random now implements
     .read_iter and .write_iter instead of .read and .write, allowing it
     to also implement .splice_read and .splice_write, which makes
     splice(2) work again after it was broken here (and in many other
     places in the tree) during the set_fs() removal. This was a bit of
     a last minute arrival from Jens that hasn't had as much time to
     bake, so I'll be keeping my eye on this as well, but it seems
     fairly ordinary. Unfortunately, read_iter() is around 3% slower
     than read() in my tests, which I'm not thrilled about. But Jens and
     Al, spurred by this observation, seem to be making progress in
     removing the bottlenecks on the iter paths in the VFS layer in
     general, which should remove the performance gap for all drivers.

   - Assorted other bug fixes, cleanups, and optimizations.

   - A small SipHash cleanup"

* tag 'random-5.19-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (49 commits)
  random: check for signals after page of pool writes
  random: wire up fops->splice_{read,write}_iter()
  random: convert to using fops->write_iter()
  random: convert to using fops->read_iter()
  random: unify batched entropy implementations
  random: move randomize_page() into mm where it belongs
  random: remove mostly unused async readiness notifier
  random: remove get_random_bytes_arch() and add rng_has_arch_random()
  random: move initialization functions out of hot pages
  random: make consistent use of buf and len
  random: use proper return types on get_random_{int,long}_wait()
  random: remove extern from functions in header
  random: use static branch for crng_ready()
  random: credit architectural init the exact amount
  random: handle latent entropy and command line from random_init()
  random: use proper jiffies comparison macro
  random: remove ratelimiting for in-kernel unseeded randomness
  random: move initialization out of reseeding hot path
  random: avoid initializing twice in credit race
  random: use symbolic constants for crng_init states
  ...
2022-05-24 11:58:10 -07:00
Yang Li
dc60001e1a xtensa: Return true/false (not 1/0) from bool function
Return boolean values ("true" or "false") instead of 1 or 0 from bool
function. This fixes the following warnings from coccicheck:

./arch/xtensa/kernel/traps.c:304:10-11: WARNING: return of 0/1 in
function 'check_div0' with return type bool

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Message-Id: <20220518230953.112266-1-yang.lee@linux.alibaba.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-23 00:33:05 -07:00
Max Filippov
5cc5f19f88 xtensa: improve call0 ABI probing
When call0 userspace ABI support by probing is enabled instructions that
cause illegal instruction exception when PS.WOE is clear are retried
with PS.WOE set before calling c-level exception handler. Record user pc
at which PS.WOE was set in the fast exception handler and clear PS.WOE
in the c-level exception handler if we get there from the same address.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-17 03:35:43 -07:00
Max Filippov
d74862007e xtensa: support artificial division by 0 exception
On xtensa cores wihout hardware division option division support
functions from libgcc react to division by 0 attempt by executing
illegal instruction followed by the characters 'DIV0'. Recognize this
pattern in illegal instruction exception handler and convert it to
division by 0.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-17 03:35:43 -07:00
Jason A. Donenfeld
e10e2f5803 xtensa: use fallback for random_get_entropy() instead of zero
In the event that random_get_entropy() can't access a cycle counter or
similar, falling back to returning 0 is really not the best we can do.
Instead, at least calling random_get_entropy_fallback() would be
preferable, because that always needs to return _something_, even
falling back to jiffies eventually. It's not as though
random_get_entropy_fallback() is super high precision or guaranteed to
be entropic, but basically anything that's not zero all the time is
better than returning zero all the time.

This is accomplished by just including the asm-generic code like on
other architectures, which means we can get rid of the empty stub
function here.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-05-13 23:59:23 +02:00
Max Filippov
408b1d3c0e xtensa: add trap handler for division by zero
Add c-level handler for the division by zero exception and kill the task
if it was thrown from the kernel space or send SIGFPE otherwise.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-13 08:43:36 -07:00
Eric W. Biederman
4a3d2717d1 ptrace/xtensa: Replace PT_SINGLESTEP with TIF_SINGLESTEP
xtensa is the last user of the PT_SINGLESTEP flag.  Changing tsk->ptrace in
user_enable_single_step and user_disable_single_step without locking could
potentiallly cause problems.

So use a thread info flag instead of a flag in tsk->ptrace.  Use TIF_SINGLESTEP
that xtensa already had defined but unused.

Remove the definitions of PT_SINGLESTEP and PT_BLOCKSTEP as they have no more users.

Cc: stable@vger.kernel.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/20220505182645.497868-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-05-11 14:33:44 -05:00
Yi Yang
b011946d03 xtensa/simdisk: fix proc_read_simdisk()
The commit a69755b187 ("xtensa simdisk: switch to proc_create_data()")
split read operation into two parts, first retrieving the path when it's
non-null and second retrieving the trailing '\n'. However when the path
is non-null the first simple_read_from_buffer updates ppos, and the
second simple_read_from_buffer returns 0 if ppos is greater than 1 (i.e.
almost always). As a result reading from that proc file is almost always
empty.

Fix it by making a temporary copy of the path with the trailing '\n' and
using simple_read_from_buffer on that copy.

Cc: stable@vger.kernel.org
Fixes: a69755b187 ("xtensa simdisk: switch to proc_create_data()")
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-11 02:15:38 -07:00