The unusual function calling conventions on SuperH ended up causing
sync_file_range to have the wrong argument order, with the 'flags'
argument getting sorted before 'nbytes' by the compiler.
In userspace, I found that musl, glibc, uclibc and strace all expect the
normal calling conventions with 'nbytes' last, so changing the kernel
to match them should make all of those work.
In order to be able to also fix libc implementations to work with existing
kernels, they need to be able to tell which ABI is used. An easy way
to do this is to add yet another system call using the sync_file_range2
ABI that works the same on all architectures.
Old user binaries can now work on new kernels, and new binaries can
try the new sync_file_range2() to work with new kernels or fall back
to the old sync_file_range() version if that doesn't exist.
Cc: stable@vger.kernel.org
Fixes: 75c92acdd5 ("sh: Wire up new syscalls.")
Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Patch series "Introduce mseal", v10.
This patchset proposes a new mseal() syscall for the Linux kernel.
In a nutshell, mseal() protects the VMAs of a given virtual memory range
against modifications, such as changes to their permission bits.
Modern CPUs support memory permissions, such as the read/write (RW) and
no-execute (NX) bits. Linux has supported NX since the release of kernel
version 2.6.8 in August 2004 [1]. The memory permission feature improves
the security stance on memory corruption bugs, as an attacker cannot
simply write to arbitrary memory and point the code to it. The memory
must be marked with the X bit, or else an exception will occur.
Internally, the kernel maintains the memory permissions in a data
structure called VMA (vm_area_struct). mseal() additionally protects the
VMA itself against modifications of the selected seal type.
Memory sealing is useful to mitigate memory corruption issues where a
corrupted pointer is passed to a memory management system. For example,
such an attacker primitive can break control-flow integrity guarantees
since read-only memory that is supposed to be trusted can become writable
or .text pages can get remapped. Memory sealing can automatically be
applied by the runtime loader to seal .text and .rodata pages and
applications can additionally seal security critical data at runtime. A
similar feature already exists in the XNU kernel with the
VM_FLAGS_PERMANENT [3] flag and on OpenBSD with the mimmutable syscall
[4]. Also, Chrome wants to adopt this feature for their CFI work [2] and
this patchset has been designed to be compatible with the Chrome use case.
Two system calls are involved in sealing the map: mmap() and mseal().
The new mseal() is an syscall on 64 bit CPU, and with following signature:
int mseal(void addr, size_t len, unsigned long flags)
addr/len: memory range.
flags: reserved.
mseal() blocks following operations for the given memory range.
1> Unmapping, moving to another location, and shrinking the size,
via munmap() and mremap(), can leave an empty space, therefore can
be replaced with a VMA with a new set of attributes.
2> Moving or expanding a different VMA into the current location,
via mremap().
3> Modifying a VMA via mmap(MAP_FIXED).
4> Size expansion, via mremap(), does not appear to pose any specific
risks to sealed VMAs. It is included anyway because the use case is
unclear. In any case, users can rely on merging to expand a sealed VMA.
5> mprotect() and pkey_mprotect().
6> Some destructive madvice() behaviors (e.g. MADV_DONTNEED) for anonymous
memory, when users don't have write permission to the memory. Those
behaviors can alter region contents by discarding pages, effectively a
memset(0) for anonymous memory.
The idea that inspired this patch comes from Stephen Röttger’s work in
V8 CFI [5]. Chrome browser in ChromeOS will be the first user of this
API.
Indeed, the Chrome browser has very specific requirements for sealing,
which are distinct from those of most applications. For example, in the
case of libc, sealing is only applied to read-only (RO) or read-execute
(RX) memory segments (such as .text and .RELRO) to prevent them from
becoming writable, the lifetime of those mappings are tied to the lifetime
of the process.
Chrome wants to seal two large address space reservations that are managed
by different allocators. The memory is mapped RW- and RWX respectively
but write access to it is restricted using pkeys (or in the future ARM
permission overlay extensions). The lifetime of those mappings are not
tied to the lifetime of the process, therefore, while the memory is
sealed, the allocators still need to free or discard the unused memory.
For example, with madvise(DONTNEED).
However, always allowing madvise(DONTNEED) on this range poses a security
risk. For example if a jump instruction crosses a page boundary and the
second page gets discarded, it will overwrite the target bytes with zeros
and change the control flow. Checking write-permission before the discard
operation allows us to control when the operation is valid. In this case,
the madvise will only succeed if the executing thread has PKEY write
permissions and PKRU changes are protected in software by control-flow
integrity.
Although the initial version of this patch series is targeting the Chrome
browser as its first user, it became evident during upstream discussions
that we would also want to ensure that the patch set eventually is a
complete solution for memory sealing and compatible with other use cases.
The specific scenario currently in mind is glibc's use case of loading and
sealing ELF executables. To this end, Stephen is working on a change to
glibc to add sealing support to the dynamic linker, which will seal all
non-writable segments at startup. Once this work is completed, all
applications will be able to automatically benefit from these new
protections.
In closing, I would like to formally acknowledge the valuable
contributions received during the RFC process, which were instrumental in
shaping this patch:
Jann Horn: raising awareness and providing valuable insights on the
destructive madvise operations.
Liam R. Howlett: perf optimization.
Linus Torvalds: assisting in defining system call signature and scope.
Theo de Raadt: sharing the experiences and insight gained from
implementing mimmutable() in OpenBSD.
MM perf benchmarks
==================
This patch adds a loop in the mprotect/munmap/madvise(DONTNEED) to
check the VMAs’ sealing flag, so that no partial update can be made,
when any segment within the given memory range is sealed.
To measure the performance impact of this loop, two tests are developed.
[8]
The first is measuring the time taken for a particular system call,
by using clock_gettime(CLOCK_MONOTONIC). The second is using
PERF_COUNT_HW_REF_CPU_CYCLES (exclude user space). Both tests have
similar results.
The tests have roughly below sequence:
for (i = 0; i < 1000, i++)
create 1000 mappings (1 page per VMA)
start the sampling
for (j = 0; j < 1000, j++)
mprotect one mapping
stop and save the sample
delete 1000 mappings
calculates all samples.
Below tests are performed on Intel(R) Pentium(R) Gold 7505 @ 2.00GHz,
4G memory, Chromebook.
Based on the latest upstream code:
The first test (measuring time)
syscall__ vmas t t_mseal delta_ns per_vma %
munmap__ 1 909 944 35 35 104%
munmap__ 2 1398 1502 104 52 107%
munmap__ 4 2444 2594 149 37 106%
munmap__ 8 4029 4323 293 37 107%
munmap__ 16 6647 6935 288 18 104%
munmap__ 32 11811 12398 587 18 105%
mprotect 1 439 465 26 26 106%
mprotect 2 1659 1745 86 43 105%
mprotect 4 3747 3889 142 36 104%
mprotect 8 6755 6969 215 27 103%
mprotect 16 13748 14144 396 25 103%
mprotect 32 27827 28969 1142 36 104%
madvise_ 1 240 262 22 22 109%
madvise_ 2 366 442 76 38 121%
madvise_ 4 623 751 128 32 121%
madvise_ 8 1110 1324 215 27 119%
madvise_ 16 2127 2451 324 20 115%
madvise_ 32 4109 4642 534 17 113%
The second test (measuring cpu cycle)
syscall__ vmas cpu cmseal delta_cpu per_vma %
munmap__ 1 1790 1890 100 100 106%
munmap__ 2 2819 3033 214 107 108%
munmap__ 4 4959 5271 312 78 106%
munmap__ 8 8262 8745 483 60 106%
munmap__ 16 13099 14116 1017 64 108%
munmap__ 32 23221 24785 1565 49 107%
mprotect 1 906 967 62 62 107%
mprotect 2 3019 3203 184 92 106%
mprotect 4 6149 6569 420 105 107%
mprotect 8 9978 10524 545 68 105%
mprotect 16 20448 21427 979 61 105%
mprotect 32 40972 42935 1963 61 105%
madvise_ 1 434 497 63 63 115%
madvise_ 2 752 899 147 74 120%
madvise_ 4 1313 1513 200 50 115%
madvise_ 8 2271 2627 356 44 116%
madvise_ 16 4312 4883 571 36 113%
madvise_ 32 8376 9319 943 29 111%
Based on the result, for 6.8 kernel, sealing check adds
20-40 nano seconds, or around 50-100 CPU cycles, per VMA.
In addition, I applied the sealing to 5.10 kernel:
The first test (measuring time)
syscall__ vmas t tmseal delta_ns per_vma %
munmap__ 1 357 390 33 33 109%
munmap__ 2 442 463 21 11 105%
munmap__ 4 614 634 20 5 103%
munmap__ 8 1017 1137 120 15 112%
munmap__ 16 1889 2153 263 16 114%
munmap__ 32 4109 4088 -21 -1 99%
mprotect 1 235 227 -7 -7 97%
mprotect 2 495 464 -30 -15 94%
mprotect 4 741 764 24 6 103%
mprotect 8 1434 1437 2 0 100%
mprotect 16 2958 2991 33 2 101%
mprotect 32 6431 6608 177 6 103%
madvise_ 1 191 208 16 16 109%
madvise_ 2 300 324 24 12 108%
madvise_ 4 450 473 23 6 105%
madvise_ 8 753 806 53 7 107%
madvise_ 16 1467 1592 125 8 108%
madvise_ 32 2795 3405 610 19 122%
The second test (measuring cpu cycle)
syscall__ nbr_vma cpu cmseal delta_cpu per_vma %
munmap__ 1 684 715 31 31 105%
munmap__ 2 861 898 38 19 104%
munmap__ 4 1183 1235 51 13 104%
munmap__ 8 1999 2045 46 6 102%
munmap__ 16 3839 3816 -23 -1 99%
munmap__ 32 7672 7887 216 7 103%
mprotect 1 397 443 46 46 112%
mprotect 2 738 788 50 25 107%
mprotect 4 1221 1256 35 9 103%
mprotect 8 2356 2429 72 9 103%
mprotect 16 4961 4935 -26 -2 99%
mprotect 32 9882 10172 291 9 103%
madvise_ 1 351 380 29 29 108%
madvise_ 2 565 615 49 25 109%
madvise_ 4 872 933 61 15 107%
madvise_ 8 1508 1640 132 16 109%
madvise_ 16 3078 3323 245 15 108%
madvise_ 32 5893 6704 811 25 114%
For 5.10 kernel, sealing check adds 0-15 ns in time, or 10-30
CPU cycles, there is even decrease in some cases.
It might be interesting to compare 5.10 and 6.8 kernel
The first test (measuring time)
syscall__ vmas t_5_10 t_6_8 delta_ns per_vma %
munmap__ 1 357 909 552 552 254%
munmap__ 2 442 1398 956 478 316%
munmap__ 4 614 2444 1830 458 398%
munmap__ 8 1017 4029 3012 377 396%
munmap__ 16 1889 6647 4758 297 352%
munmap__ 32 4109 11811 7702 241 287%
mprotect 1 235 439 204 204 187%
mprotect 2 495 1659 1164 582 335%
mprotect 4 741 3747 3006 752 506%
mprotect 8 1434 6755 5320 665 471%
mprotect 16 2958 13748 10790 674 465%
mprotect 32 6431 27827 21397 669 433%
madvise_ 1 191 240 49 49 125%
madvise_ 2 300 366 67 33 122%
madvise_ 4 450 623 173 43 138%
madvise_ 8 753 1110 357 45 147%
madvise_ 16 1467 2127 660 41 145%
madvise_ 32 2795 4109 1314 41 147%
The second test (measuring cpu cycle)
syscall__ vmas cpu_5_10 c_6_8 delta_cpu per_vma %
munmap__ 1 684 1790 1106 1106 262%
munmap__ 2 861 2819 1958 979 327%
munmap__ 4 1183 4959 3776 944 419%
munmap__ 8 1999 8262 6263 783 413%
munmap__ 16 3839 13099 9260 579 341%
munmap__ 32 7672 23221 15549 486 303%
mprotect 1 397 906 509 509 228%
mprotect 2 738 3019 2281 1140 409%
mprotect 4 1221 6149 4929 1232 504%
mprotect 8 2356 9978 7622 953 423%
mprotect 16 4961 20448 15487 968 412%
mprotect 32 9882 40972 31091 972 415%
madvise_ 1 351 434 82 82 123%
madvise_ 2 565 752 186 93 133%
madvise_ 4 872 1313 442 110 151%
madvise_ 8 1508 2271 763 95 151%
madvise_ 16 3078 4312 1234 77 140%
madvise_ 32 5893 8376 2483 78 142%
From 5.10 to 6.8
munmap: added 250-550 ns in time, or 500-1100 in cpu cycle, per vma.
mprotect: added 200-750 ns in time, or 500-1200 in cpu cycle, per vma.
madvise: added 33-50 ns in time, or 70-110 in cpu cycle, per vma.
In comparison to mseal, which adds 20-40 ns or 50-100 CPU cycles, the
increase from 5.10 to 6.8 is significantly larger, approximately ten times
greater for munmap and mprotect.
When I discuss the mm performance with Brian Makin, an engineer who worked
on performance, it was brought to my attention that such performance
benchmarks, which measuring millions of mm syscall in a tight loop, may
not accurately reflect real-world scenarios, such as that of a database
service. Also this is tested using a single HW and ChromeOS, the data
from another HW or distribution might be different. It might be best to
take this data with a grain of salt.
This patch (of 5):
Wire up mseal syscall for all architectures.
Link: https://lkml.kernel.org/r/20240415163527.626541-1-jeffxu@chromium.org
Link: https://lkml.kernel.org/r/20240415163527.626541-2-jeffxu@chromium.org
Signed-off-by: Jeff Xu <jeffxu@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Jann Horn <jannh@google.com> [Bug #2]
Cc: Jeff Xu <jeffxu@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Jorge Lucangeli Obes <jorgelo@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Cc: Stephen Röttger <sroettger@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Amer Al Shanawany <amer.shanawany@gmail.com>
Cc: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
These are a few cross-architecture cleanup patches:
- Thomas Zimmermann works on separating fbdev support from the asm/video.h
contents that may be used by either the old fbdev drivers or the
newer drm display code.
- Thorsten Blum contributes cleanups for the generic bitops code
and asm-generic/bug.h
- I remove the orphaned include/asm-generic/page.h header that used to
included by long-removed mmu-less architectures.
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Merge tag 'asm-generic-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic cleanups from Arnd Bergmann:
"These are a few cross-architecture cleanup patches:
- separate out fbdev support from the asm/video.h contents that may
be used by either the old fbdev drivers or the newer drm display
code (Thomas Zimmermann)
- cleanups for the generic bitops code and asm-generic/bug.h
(Thorsten Blum)
- remove the orphaned include/asm-generic/page.h header that used to
be included by long-removed mmu-less architectures (me)"
* tag 'asm-generic-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
arch: Fix name collision with ACPI's video.o
bug: Improve comment
asm-generic: remove unused asm-generic/page.h
arch: Rename fbdev header and source files
arch: Remove struct fb_info from video helpers
arch: Select fbdev helpers with CONFIG_VIDEO
bitops: Change function return types from long to int
documented (hopefully adequately) in the respective changelogs. Notable
series include:
- Lucas Stach has provided some page-mapping
cleanup/consolidation/maintainability work in the series "mm/treewide:
Remove pXd_huge() API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one
test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being allocated:
number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in largely
similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene" Johannes
Weiner has fixed the page allocator's handling of migratetype requests,
with resulting improvements in compaction efficiency.
- In the series "make the hugetlb migration strategy consistent" Baolin
Wang has fixed a hugetlb migration issue, which should improve hugetlb
allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when memory
almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting" Kairui
Song has optimized pagecache insertion, yielding ~10% performance
improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various page->flags
cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb
functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series
"mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs. This
is a simple first-cut implementation for now. The series is "support
multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in the
series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts in
the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call it
GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to
use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes". Fixes
the initialization code so that migration between different memory types
works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant driver
in the series "mm: follow_pte() improvements and acrn follow_pte()
fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to folio
in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size THP's
in the series "mm: add per-order mTHP alloc and swpout counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled
and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His series
"mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes
the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback instrumentation
in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series "Fix
and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the
series "Improve anon_vma scalability for anon VMAs". Intel's test bot
reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking".
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Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:
"The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.
Notable series include:
- Lucas Stach has provided some page-mapping cleanup/consolidation/
maintainability work in the series "mm/treewide: Remove pXd_huge()
API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
one test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being
allocated: number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in
largely similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene"
Johannes Weiner has fixed the page allocator's handling of
migratetype requests, with resulting improvements in compaction
efficiency.
- In the series "make the hugetlb migration strategy consistent"
Baolin Wang has fixed a hugetlb migration issue, which should
improve hugetlb allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when
memory almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting"
Kairui Song has optimized pagecache insertion, yielding ~10%
performance improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various
page->flags cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series:
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert
hugetlb functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
series "mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs.
This is a simple first-cut implementation for now. The series is
"support multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in
the series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts
in the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call
it GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
path to use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes".
Fixes the initialization code so that migration between different
memory types works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant
driver in the series "mm: follow_pte() improvements and acrn
follow_pte() fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to
folio in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size
THP's in the series "mm: add per-order mTHP alloc and swpout
counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap
same-filled and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His
series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
optimizes the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback
instrumentation in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series
"Fix and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
the series "Improve anon_vma scalability for anon VMAs". Intel's
test bot reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as
XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking""
* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
selftests: cgroup: add tests to verify the zswap writeback path
mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
mm/damon/core: fix return value from damos_wmark_metric_value
mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
selftests: cgroup: remove redundant enabling of memory controller
Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
Docs/mm/damon/design: use a list for supported filters
Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
selftests/damon: classify tests for functionalities and regressions
selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
selftests/damon: add a test for DAMOS quota goal
...
- Avoid 'constexpr', which is a keyword in C23
- Allow 'dtbs_check' and 'dt_compatible_check' run independently of
'dt_binding_check'
- Fix weak references to avoid GOT entries in position-independent
code generation
- Convert the last use of 'optional' property in arch/sh/Kconfig
- Remove support for the 'optional' property in Kconfig
- Remove support for Clang's ThinLTO caching, which does not work with
the .incbin directive
- Change the semantics of $(src) so it always points to the source
directory, which fixes Makefile inconsistencies between upstream and
downstream
- Fix 'make tar-pkg' for RISC-V to produce a consistent package
- Provide reasonable default coverage for objtool, sanitizers, and
profilers
- Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
- Remove the last use of tristate choice in drivers/rapidio/Kconfig
- Various cleanups and fixes in Kconfig
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Merge tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Avoid 'constexpr', which is a keyword in C23
- Allow 'dtbs_check' and 'dt_compatible_check' run independently of
'dt_binding_check'
- Fix weak references to avoid GOT entries in position-independent code
generation
- Convert the last use of 'optional' property in arch/sh/Kconfig
- Remove support for the 'optional' property in Kconfig
- Remove support for Clang's ThinLTO caching, which does not work with
the .incbin directive
- Change the semantics of $(src) so it always points to the source
directory, which fixes Makefile inconsistencies between upstream and
downstream
- Fix 'make tar-pkg' for RISC-V to produce a consistent package
- Provide reasonable default coverage for objtool, sanitizers, and
profilers
- Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
- Remove the last use of tristate choice in drivers/rapidio/Kconfig
- Various cleanups and fixes in Kconfig
* tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits)
kconfig: use sym_get_choice_menu() in sym_check_prop()
rapidio: remove choice for enumeration
kconfig: lxdialog: remove initialization with A_NORMAL
kconfig: m/nconf: merge two item_add_str() calls
kconfig: m/nconf: remove dead code to display value of bool choice
kconfig: m/nconf: remove dead code to display children of choice members
kconfig: gconf: show checkbox for choice correctly
kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal
Makefile: remove redundant tool coverage variables
kbuild: provide reasonable defaults for tool coverage
modules: Drop the .export_symbol section from the final modules
kconfig: use menu_list_for_each_sym() in sym_check_choice_deps()
kconfig: use sym_get_choice_menu() in conf_write_defconfig()
kconfig: add sym_get_choice_menu() helper
kconfig: turn defaults and additional prompt for choice members into error
kconfig: turn missing prompt for choice members into error
kconfig: turn conf_choice() into void function
kconfig: use linked list in sym_set_changed()
kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED
kconfig: gconf: remove debug code
...
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Merge tag 'printk-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Use no_printk() instead of "if (0) printk()" constructs to avoid
generating printk index for messages disabled at compile time
- Remove deprecated strncpy/strcpy from printk.c
- Remove redundant CONFIG_BASE_FULL in favor of CONFIG_BASE_SMALL
* tag 'printk-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: cleanup deprecated uses of strncpy/strcpy
printk: Remove redundant CONFIG_BASE_FULL
printk: Change type of CONFIG_BASE_SMALL to bool
printk: Fix LOG_CPU_MAX_BUF_SHIFT when BASE_SMALL is enabled
ceph: Use no_printk() helper
dyndbg: Use *no_printk() helpers
dev_printk: Add and use dev_no_printk()
printk: Let no_printk() use _printk()
Now Kbuild provides reasonable defaults for objtool, sanitizers, and
profilers.
Remove redundant variables.
Note:
This commit changes the coverage for some objects:
- include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV
- include arch/sparc/vdso/vdso-image-*.o into UBSAN
- include arch/sparc/vdso/vma.o into UBSAN
- include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vma.o into GCOV, KCOV
- include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV
I believe these are positive effects because all of them are kernel
space objects.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Roberto Sassu <roberto.sassu@huawei.com>
arch/sh/kernel/smp.c:326:5: warning: no previous prototype for 'setup_profiling_timer' [-Wmissing-prototypes]
The function is unconditionally defined in smp.c, but conditionally
declared in <linux/profile.h>.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/effa5eecbd2389c6661974e91bb834db210989ea.1715606232.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/boards/of-generic.c:146:20: warning: no previous prototype for 'arch_init_clk_ops' [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/942621553ed82e3331e2e91485b643892d2d08bc.1715606232.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
The G2-to-PCI bridge chip found in SEGA Dreamcast assumes P2 area
relative addresses.
Set the appropriate IOPORT base offset.
Tested-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20240511191614.68561-2-contact@artur-rojek.eu
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
CONFIG_BASE_FULL is equivalent to !CONFIG_BASE_SMALL and is enabled by
default: CONFIG_BASE_SMALL is the special case to take care of.
So, remove CONFIG_BASE_FULL and move the config choice to
CONFIG_BASE_SMALL (which defaults to 'n')
For defconfigs explicitely disabling BASE_FULL, explicitely enable
BASE_SMALL.
For defconfigs explicitely enabling BASE_FULL, drop it as it is the
default.
Signed-off-by: Yoann Congal <yoann.congal@smile.fr>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240505080343.1471198-4-yoann.congal@smile.fr
Signed-off-by: Petr Mladek <pmladek@suse.com>
We want to limit the use of page_mapcount() to the places where it is
absolutely necessary.
We're already using folio_mapped in copy_user_highpage() and
copy_to_user_page() for a similar purpose so ... let's also simply use it
for copy_from_user_page().
There is no change for small folios. Likely we won't stumble over many
large folios on sh in that code either way.
Link: https://lkml.kernel.org/r/20240409192301.907377-13-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The per-architecture fbdev code has no dependencies on fbdev and can
be used for any video-related subsystem. Rename the files to 'video'.
Use video-sti.c on parisc as the source file depends on CONFIG_STI_CORE.
On arc, arm, arm64, sh, and um the asm header file is an empty wrapper
around the file in asm-generic. Let Kbuild generate the file. The build
system does this automatically. Only um needs to generate video.h
explicitly, so that it overrides the host architecture's header. The
latter would otherwise interfere with the build.
Further update all includes statements, include guards, and Makefiles.
Also update a few strings and comments to refer to video instead of
fbdev.
v3:
- arc, arm, arm64, sh: generate asm header via build system (Sam,
Helge, Arnd)
- um: rename fb.h to video.h
- fix typo in commit message (Sam)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
These are generated files. Prefix them with $(obj)/ instead of $(src)/.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Helge Deller <deller@gmx.de>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
The 'choice' statement is primarily used to exclusively select one
option, but the 'optional' property allows all entries to be disabled.
This feature is rarely used. In fact, it is only used in arch/sh/Kconfig
because the equivalent outcome can be achieved by inserting one more
entry.
The 'optional' property support will be removed from Kconfig.
This commit replaces the 'optional' property with a dummy option,
CMDLINE_FROM_BOOTLOADER, as seen in some other architectures.
Note:
The 'default CMDLINE_OVERWRITE' statement does not work as intended
in combination with 'optional'. If neither CONFIG_CMDLINE_OVERWRITE
nor CONFIG_CMDLINE_EXTEND is specified in a defconfig file, both of
them are disabled. This is a bug. To maintain the current behavior,
I added CONFIG_CMDLINE_FROM_BOOTLOADER=y to those defconfig files.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/boot/compressed/misc.c:110:6: warning: no previous prototype for ‘ftrace_stub’ [-Wmissing-prototypes]
arch/sh/boot/compressed/misc.c:113:6: warning: no previous prototype for ‘arch_ftrace_ops_list_func’ [-Wmissing-prototypes]
arch/sh/boot/compressed/misc.c:123:6: warning: no previous prototype for ‘decompress_kernel’ [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/b7ea770a3bf26fb2a5f59f4bb83072b2526f7134.1713959841.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Commit 37744feebc ("sh: remove sh5 support") in v5.8 forgot to
remove the sh5 cache handling.
Suggested-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/23e9b3fd0d78e46c9fc1835852ba226aba92c3ca.1713959531.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
The J2 SPI controller bindings never allowed spi-max-frequency property
in the controller node. Neither old spi-bus.txt bindings, nor new DT
schema allows it. Linux driver does not parse that property from
controller node, thus drop it from DTS as incorrect hardware
description. The SPI child device has already the same property with
the same value, so functionality should not be affected.
Cc: Kousik Sanagavarapu <five231003@gmail.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Tested-by: Rob Landley <rob@landley.net>
Link: https://lore.kernel.org/r/20240322064221.25776-1-krzysztof.kozlowski@linaro.org
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20240306211947.97103-2-u.kleine-koenig@pengutronix.de
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/boards/board-sh7785lcr.c:298:13: warning: no previous prototype for ‘init_sh7785lcr_IRQ’ [-Wmissing-prototypes]
There are no users outside this file, so make it static.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/cbe9da98a1106cdab686766e2f23f768399dbdbf.1709579038.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/cpu/sh4a/setup-sh7757.c:1240:13: warning: no previous prototype for ‘plat_mem_setup’ [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/c9c26472151d16a2ca91f14bccd64af07a6abdd8.1709579038.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/boards/board-sh7757lcr.c:572:13: warning: no previous prototype for 'init_sh7757lcr_IRQ' [-Wmissing-prototypes]
There are no users outside this file, so make it static.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/fba00424b5b0bee0f9b9cbc63d649a86854d202f.1709579038.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/boards/mach-sh03/rtc.c:123:5: warning: no previous prototype for ‘sh03_rtc_settimeofday’ [-Wmissing-prototypes]
There are no users outside this file, so make it static.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/95417f2a3eb1561af7c2ee064efbc3ef3f03dac3.1709579038.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/boards/mach-highlander/pinmux-r7785rp.c:9:13: warning: no previous prototype for ‘highlander_plat_pinmux_setup’ [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/bbbc833d2c5b565122baaf9277ddf4a2f2cadead.1709579038.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
If CONFIG_SH_DSP=y (e.g. se7343_defconfig):
arch/sh/kernel/traps_32.c:572:5: warning: no previous prototype for ‘is_dsp_inst’ [-Wmissing-prototypes]
There are no users outside this file, so make it static.
While at it, convert the dummy for the CONFIG_SH_DSP=n case from a macro
to a static inline function, to increase type-safety.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/8525fe446e7f24649a83b8cd6ca8b736ab746b80.1709579038.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/cpu/init.c:99:29: warning: no previous prototype for 'l2_cache_init' [-Wmissing-prototypes]
arch/sh/kernel/cpu/sh4a/setup-sh7723.c:422:6: warning: no previous prototype for 'l2_cache_init' [-Wmissing-prototypes]
arch/sh/kernel/cpu/sh4a/setup-sh7724.c:842:6: warning: no previous prototype for 'l2_cache_init' [-Wmissing-prototypes]
arch/sh/mm/cache-j2.c:48:13: warning: no previous prototype for 'j2_cache_init' [-Wmissing-prototypes]
arch/sh/mm/cache-sh2.c:85:13: warning: no previous prototype for 'sh2_cache_init' [-Wmissing-prototypes]
arch/sh/mm/cache-sh2a.c:181:13: warning: no previous prototype for 'sh2a_cache_init' [-Wmissing-prototypes]
arch/sh/mm/cache-sh3.c:90:13: warning: no previous prototype for 'sh3_cache_init' [-Wmissing-prototypes]
arch/sh/mm/cache-sh4.c:384:13: warning: no previous prototype for 'sh4_cache_init' [-Wmissing-prototypes]
arch/sh/mm/cache-shx3.c:18:13: warning: no previous prototype for 'shx3_cache_init' [-Wmissing-prototypes]
arch/sh/mm/flush-sh4.c:106:13: warning: no previous prototype for 'sh4__flush_region_init' [-Wmissing-prototypes]
arch/sh/mm/cache-sh7705.c:190:13: warning: no previous prototype for 'sh7705_cache_init' [-Wmissing-prototypes]
Fix this by moving all cache-related forward declarations to
<asm/cacheflush.h>, and by including the latter where needed.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/f47ab87636d16db4c47bebe1bf62650045f61989.1709579038.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
dma_extend(), get_dma_info_by_name(), register_chan_caps(), and
request_dma_bycap() are unused. Remove them, and all related code.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/2beb81fdd7592a94329e3c9a6ba56959f6094019.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/dwarf.c:347:19: warning: no previous prototype for 'dwarf_lookup_fde' [-Wmissing-prototypes]
There are no users outside this file, so make it static.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/55e8261a354e8ec4d375754e404c6c1d303af715.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/kprobes.c:299:15: warning: no previous prototype for 'trampoline_probe_handler' [-Wmissing-prototypes]
There are no users outside this file, so make it static.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/42f30b7f767ee1293f6e687a605f7d907ae2daa6.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/kprobes.c:52:16: warning: no previous prototype for 'arch_copy_kprobe' [-Wmissing-prototypes]
Although SH kprobes support was only merged in v2.6.28, it missed the
earlier removal of the arch_copy_kprobe() callback in v2.6.15.
Based on the powerpc part of commit 49a2a1b83b ("[PATCH] kprobes:
changed from using spinlock to mutex").
Fixes: d39f545014 ("sh: Add kprobes support.")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/717d47a19689cc944fae6e981a1ad7cae1642c89.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/smp.c:173:17: warning: no previous prototype for 'start_secondary' [-Wmissing-prototypes]
arch/sh/kernel/smp.c:324:5: warning: no previous prototype for 'setup_profiling_timer' [-Wmissing-prototypes]
Make start_secondary() static, as it is only used in this file.
Include <linux/profile.h> to fix the other warning.
There are no users outside this file, so make it static.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/6b6b9a84b30ee56f57f409a7550c69d4aece5dc3.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/cpu/sh4a/setup-sh7786.c:411:13: warning: no previous prototype for 'sh7786_usb_use_exclock' [-Wmissing-prototypes]
Upstream never had a user of sh7786_usb_use_exclock(), remove it.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/a87c6c0edcf81937b8eb2c899d286d82d71ad513.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/cpu/sh2a/opcode_helper.c:34:14: warning: no previous prototype for 'instruction_size' [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/8314dd9a966394dd1fd82d88095c57d9778fcfc9.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/drivers/dma/dma-api.c:164:5: warning: no previous prototype for 'dmac_search_free_channel' [-Wmissing-prototypes]
dmac_search_free_channel() never had a user in upstream, remove it.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/82d5efdde44f9489c5a7d11d0a19750445116c95.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/mm/nommu.c:76:13: warning: no previous prototype for 'kmap_coherent_init' [-Wmissing-prototypes]
arch/sh/mm/nommu.c:80:7: warning: no previous prototype for 'kmap_coherent' [-Wmissing-prototypes]
arch/sh/mm/nommu.c:86:6: warning: no previous prototype for 'kunmap_coherent' [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/d4b2a43fcedddee3d27cfd87ff2e0bf511588aa0.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/ftrace.c:130:6: warning: no previous prototype for ‘arch_ftrace_nmi_enter’ [-Wmissing-prototypes]
arch/sh/kernel/ftrace.c:140:6: warning: no previous prototype for ‘arch_ftrace_nmi_exit’ [-Wmissing-prototypes]
arch/sh/kernel/ftrace.c:316:6: warning: no previous prototype for ‘prepare_ftrace_return’ [-Wmissing-prototypes]
Fix this by moving existing forward declarations to <asm/ftrace.h>, and
adding the missing forward declaration for prepare_ftrace_return().
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/910c8846a025e1c3b744a83ddf8e2816a3c5569d.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/hw_breakpoint.c:135:5: warning: no previous prototype for ‘arch_bp_generic_fields’ [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/566af354bf51ddc38e9eb95eac51ec00c4e42024.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/traps_32.c:735:6: warning: no previous prototype for ‘per_cpu_trap_init’ [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/a7750e57cc077ca6e27d0b9bd6b123d42894bc17.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/return_address.c:49:7: warning: no previous prototype for ‘return_address’ [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/45685f62c9132aca5dc3c028471218393b51f34c.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/kernel/cpu/sh4/fpu.c:389:6: warning: no previous prototype for ‘float_raise’ [-Wmissing-prototypes]
arch/sh/kernel/cpu/sh4/fpu.c:394:5: warning: no previous prototype for ‘float_rounding_mode’ [-Wmissing-prototypes]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/1847145fc2181313b78bea8a81e6f0269d765968.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
arch/sh/mm/pgtable.c:12:6: warning: no previous prototype for 'pgd_ctor' [-Wmissing-prototypes]
arch/sh/mm/pgtable.c:34:8: warning: no previous prototype for 'pgd_alloc' [-Wmissing-prototypes]
arch/sh/mm/pgtable.c:39:6: warning: no previous prototype for 'pgd_free' [-Wmissing-prototypes]
arch/sh/mm/pgtable.c:45:6: warning: no previous prototype for 'pud_populate' [-Wmissing-prototypes]
arch/sh/mm/pgtable.c:50:8: warning: no previous prototype for 'pmd_alloc_one' [-Wmissing-prototypes]
arch/sh/mm/pgtable.c:55:6: warning: no previous prototype for 'pmd_free' [-Wmissing-prototypes]
Make pgd_ctor() static, as it is only used in this file.
Include <asm/pgalloc.h> to fix the other warnings.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/aa1328ea3327d6685aab76d5787cb77c996052c0.1709326528.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Nowadays, we call it "GUP-fast", the external interface includes functions
like "get_user_pages_fast()", and we renamed all internal functions to
reflect that as well.
Let's make the config option reflect that.
Link: https://lkml.kernel.org/r/20240402125516.223131-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Future changes will need to add a new member to struct
vm_unmapped_area_info. This would cause trouble for any call site that
doesn't initialize the struct. Currently every caller sets each member
manually, so if new ones are added they will be uninitialized and the core
code parsing the struct will see garbage in the new member.
It could be possible to initialize the new member manually to 0 at each
call site. This and a couple other options were discussed. Having some
struct vm_unmapped_area_info instances not zero initialized will put those
sites at risk of feeding garbage into vm_unmapped_area(), if the
convention is to zero initialize the struct and any new field addition
missed a call site that initializes each field manually. So it is useful
to do things similar across the kernel.
The consensus (see links) was that in general the best way to accomplish
taking into account both code cleanliness and minimizing the chance of
introducing bugs, was to do C99 static initialization. As in: struct
vm_unmapped_area_info info = {};
With this method of initialization, the whole struct will be zero
initialized, and any statements setting fields to zero will be unneeded.
The change should not leave cleanup at the call sides.
While iterating though the possible solutions a few archs kindly acked
other variations that still zero initialized the struct. These sites have
been modified in previous changes using the pattern acked by the
respective arch.
So to be reduce the chance of bugs via uninitialized fields, perform a
tree wide change using the consensus for the best general way to do this
change. Use C99 static initializing to zero the struct and remove and
statements that simply set members to zero.
Link: https://lkml.kernel.org/r/20240326021656.202649-11-rick.p.edgecombe@intel.com
Link: https://lore.kernel.org/lkml/202402280912.33AEE7A9CF@keescook/#t
Link: https://lore.kernel.org/lkml/j7bfvig3gew3qruouxrh7z7ehjjafrgkbcmg6tcghhfh3rhmzi@wzlcoecgy5rs/
Link: https://lore.kernel.org/lkml/ec3e377a-c0a0-4dd3-9cb9-96517e54d17e@csgroup.eu/
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Deepak Gupta <debug@rivosinc.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: H. Peter Anvin (Intel) <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All implementations that aren't no-ops just set a bit in the flags, and we
want to use the folio flags rather than the page flags for that. Rename
it to arch_clear_hugetlb_flags() while we're touching it so nobody thinks
it's used for THP.
[willy@infradead.org: fix arm64 build]
Link: https://lkml.kernel.org/r/ZgQvNKGdlDkwhQEX@casper.infradead.org
Link: https://lkml.kernel.org/r/20240326171045.410737-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
