On arm64, building with CONFIG_KASAN_HW_TAGS now causes a compile-time
error:

mm/kasan/report.c: In function 'kasan_non_canonical_hook':
mm/kasan/report.c:637:20: error: 'KASAN_SHADOW_OFFSET' undeclared (first use in this function)
  637 |         if (addr < KASAN_SHADOW_OFFSET)
      |                    ^~~~~~~~~~~~~~~~~~~
mm/kasan/report.c:637:20: note: each undeclared identifier is reported only once for each function it appears in
mm/kasan/report.c:640:77: error: expected expression before ';' token
  640 |         orig_addr = (addr - KASAN_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT;

This was caused by removing the dependency on CONFIG_KASAN_INLINE that
used to prevent this from happening. Use the more specific dependency
on KASAN_SW_TAGS || KASAN_GENERIC to only ignore the function for hwasan
mode.

Link: https://lkml.kernel.org/r/20231016200925.984439-1-arnd@kernel.org
Fixes: 12ec6a919b0f ("kasan: print the original fault addr when access invalid shadow")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Haibo Li <haibo.li@mediatek.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

when the checked address is illegal,the corresponding shadow address from
kasan_mem_to_shadow may have no mapping in mmu table.  Access such shadow
address causes kernel oops.  Here is a sample about oops on arm64(VA
39bit) with KASAN_SW_TAGS and KASAN_OUTLINE on:

[ffffffb80aaaaaaa] pgd=000000005d3ce003, p4d=000000005d3ce003,
    pud=000000005d3ce003, pmd=0000000000000000
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 3 PID: 100 Comm: sh Not tainted 6.6.0-rc1-dirty #43
Hardware name: linux,dummy-virt (DT)
pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __hwasan_load8_noabort+0x5c/0x90
lr : do_ib_ob+0xf4/0x110
ffffffb80aaaaaaa is the shadow address for efffff80aaaaaaaa.
The problem is reading invalid shadow in kasan_check_range.

The generic kasan also has similar oops.

It only reports the shadow address which causes oops but not
the original address.

Commit 2f004eea("x86/kasan: Print original address on #GP")
introduce to kasan_non_canonical_hook but limit it to KASAN_INLINE.

This patch extends it to KASAN_OUTLINE mode.

Link: https://lkml.kernel.org/r/20231009073748.159228-1-haibo.li@mediatek.com
Fixes: 2f004eea("x86/kasan: Print original address on #GP")
Signed-off-by: Haibo Li <haibo.li@mediatek.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Haibo Li <haibo.li@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Malloc libraries, like jemalloc and tcalloc, take decisions on when to
call madvise independently from the code in the main application.

This sometimes results in the application page faulting on an address,
right after the malloc library has shot down the backing memory with
MADV_DONTNEED.

Usually this is harmless, because we always have some 4kB pages sitting
around to satisfy a page fault.  However, with hugetlbfs systems often
allocate only the exact number of huge pages that the application wants.

Due to TLB batching, hugetlbfs MADV_DONTNEED will free pages outside of
any lock taken on the page fault path, which can open up the following
race condition:

       CPU 1                            CPU 2

       MADV_DONTNEED
       unmap page
       shoot down TLB entry
                                       page fault
                                       fail to allocate a huge page
                                       killed with SIGBUS
       free page

Fix that race by pulling the locking from __unmap_hugepage_final_range
into helper functions called from zap_page_range_single.  This ensures
page faults stay locked out of the MADV_DONTNEED VMA until the huge pages
have actually been freed.

Link: https://lkml.kernel.org/r/20231006040020.3677377-4-riel@surriel.com
Fixes: 04ada095 ("hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing")
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Extend the locking scheme used to protect shared hugetlb mappings from
truncate vs page fault races, in order to protect private hugetlb mappings
(with resv_map) against MADV_DONTNEED.

Add a read-write semaphore to the resv_map data structure, and use that
from the hugetlb_vma_(un)lock_* functions, in preparation for closing the
race between MADV_DONTNEED and page faults.

Link: https://lkml.kernel.org/r/20231006040020.3677377-3-riel@surriel.com
Fixes: 04ada095 ("hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing")
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Patch series "hugetlbfs: close race between MADV_DONTNEED and page fault", v7.

Malloc libraries, like jemalloc and tcalloc, take decisions on when to
call madvise independently from the code in the main application.

This sometimes results in the application page faulting on an address,
right after the malloc library has shot down the backing memory with
MADV_DONTNEED.

Usually this is harmless, because we always have some 4kB pages sitting
around to satisfy a page fault.  However, with hugetlbfs systems often
allocate only the exact number of huge pages that the application wants.

Due to TLB batching, hugetlbfs MADV_DONTNEED will free pages outside of
any lock taken on the page fault path, which can open up the following
race condition:

       CPU 1                            CPU 2

       MADV_DONTNEED
       unmap page
       shoot down TLB entry
                                       page fault
                                       fail to allocate a huge page
                                       killed with SIGBUS
       free page

Fix that race by extending the hugetlb_vma_lock locking scheme to also
cover private hugetlb mappings (with resv_map), and pulling the locking
from __unmap_hugepage_final_range into helper functions called from
zap_page_range_single.  This ensures page faults stay locked out of the
MADV_DONTNEED VMA until the huge pages have actually been freed.


This patch (of 3):

Hugetlbfs leaves a dangling pointer in the VMA if mmap fails.  This has
not been a problem so far, but other code in this patch series tries to
follow that pointer.

Link: https://lkml.kernel.org/r/20231006040020.3677377-1-riel@surriel.com
Link: https://lkml.kernel.org/r/20231006040020.3677377-2-riel@surriel.com
Fixes: 04ada095 ("hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Rik van Riel <riel@surriel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When a zswap store fails due to the limit, it acquires a pool reference
and queues the shrinker.  When the shrinker runs, it drops the reference. 
However, there can be multiple store attempts before the shrinker wakes up
and runs once.  This results in reference leaks and eventual saturation
warnings for the pool refcount.

Fix this by dropping the reference again when the shrinker is already
queued.  This ensures one reference per shrinker run.

Link: https://lkml.kernel.org/r/20231006160024.170748-1-hannes@cmpxchg.org
Fixes: 45190f01 ("mm/zswap.c: add allocation hysteresis if pool limit is hit")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Chris Mason <clm@fb.com>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: <stable@vger.kernel.org>	[5.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

do_pages_move does not handle compat pointers for the page list. 
correctly.  Add in_compat_syscall check and appropriate get_user fetch
when iterating the page list.

It makes the syscall in compat mode (32-bit userspace, 64-bit kernel)
work the same way as the native 32-bit syscall again, restoring the
behavior before my broken commit 5b1b561b ("mm: simplify
compat_sys_move_pages").

More specifically, my patch moved the parsing of the 'pages' array from
the main entry point into do_pages_stat(), which left the syscall
working correctly for the 'stat' operation (nodes = NULL), while the
'move' operation (nodes != NULL) is now missing the conversion and
interprets 'pages' as an array of 64-bit pointers instead of the
intended 32-bit userspace pointers.

It is possible that nobody noticed this bug because the few
applications that actually call move_pages are unlikely to run in
compat mode because of their large memory requirements, but this
clearly fixes a user-visible regression and should have been caught by
ltp.

Link: https://lkml.kernel.org/r/20231003144857.752952-1-gregory.price@memverge.com
Fixes: 5b1b561b ("mm: simplify compat_sys_move_pages")
Signed-off-by: Gregory Price <gregory.price@memverge.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

We used to determine the number of page table entries to set for a NAPOT
hugepage by using the pte value which actually fails when the pte to set
is a swap entry.

So take advantage of a recent fix for arm64 reported in [1] which
introduces the size of the mapping as an argument of set_huge_pte_at(): we
can then use this size to compute the number of page table entries to set
for a NAPOT region.

Link: https://lkml.kernel.org/r/20230928151846.8229-3-alexghiti@rivosinc.com
Fixes: 82a1a1f3 ("riscv: mm: support Svnapot in hugetlb page")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reported-by: Ryan Roberts <ryan.roberts@arm.com>
Closes: https://lore.kernel.org/linux-arm-kernel/20230922115804.2043771-1-ryan.roberts@arm.com/ [1]
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Qinglin Pan <panqinglin2020@iscas.ac.cn>
Cc: Conor Dooley <conor@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Patch series "Fix set_huge_pte_at()".

A recent report [1] from Ryan for arm64 revealed that we do not handle
swap entries when setting a hugepage backed by a NAPOT region (the contpte
riscv equivalent).

As explained in [1], the issue was discovered by a new test in kselftest
which uses poison entries, but the symptoms are different from arm64 though:

- the riscv kernel bugs because we do not handle VM_FAULT_HWPOISON*,
  this is fixed by patch 1,
- after that, the test passes because the first pte_napot() fails (the
  poison entry does not have the N bit set), and then we only set the
  first page table entry covering the NAPOT hugepage, which is enough
  for hugetlb_fault() to correctly raise a VM_FAULT_HWPOISON wherever we
  write in this mapping since only this first page table entry is
  checked
  (see https://elixir.bootlin.com/linux/v6.6-rc3/source/mm/hugetlb.c#L6071).
  But this seems fragile so patch 2 sets all page table entries of a
  NAPOT mapping.

[1]: https://lore.kernel.org/linux-arm-kernel/20230922115804.2043771-1-ryan.roberts@arm.com/


This patch (of 2):

We used to panic when such faults were encountered but we should handle
those faults gracefully for userspace by sending a SIGBUS to the process,
like most architectures do.

Link: https://lkml.kernel.org/r/20230928151846.8229-1-alexghiti@rivosinc.com
Link: https://lkml.kernel.org/r/20230928151846.8229-2-alexghiti@rivosinc.comSigned-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Conor Dooley <conor@kernel.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Qinglin Pan <panqinglin2020@iscas.ac.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When the calling function fails after the dup_anon_vma(), the
duplication of the anon_vma is not being undone.  Add the necessary
unlink_anon_vma() call to the error paths that are missing them.

This issue showed up during inspection of the error path in vma_merge()
for an unrelated vma iterator issue.

Users may experience increased memory usage, which may be problematic as
the failure would likely be caused by a low memory situation.

Link: https://lkml.kernel.org/r/20230929183041.2835469-3-Liam.Howlett@oracle.com
Fixes: d4af56c5 ("mm: start tracking VMAs with maple tree")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

During the error path, the vma iterator may not be correctly positioned or
set to the correct range.  Undo the vma_prev() call by resetting to the
passed in address.  Re-walking to the same range will fix the range to the
area previously passed in.

Users would notice increased cycles as vma_merge() would be called an
extra time with vma == prev, and thus would fail to merge and return.

Link: https://lore.kernel.org/linux-mm/CAG48ez12VN1JAOtTNMY+Y2YnsU45yL5giS-Qn=ejtiHpgJAbdQ@mail.gmail.com/
Link: https://lkml.kernel.org/r/20230929183041.2835469-2-Liam.Howlett@oracle.com
Fixes: 18b098af ("vma_merge: set vma iterator to correct position.")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Jann Horn <jannh@google.com>
Closes: https://lore.kernel.org/linux-mm/CAG48ez12VN1JAOtTNMY+Y2YnsU45yL5giS-Qn=ejtiHpgJAbdQ@mail.gmail.com/Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Calling vm_brk_flags() with flags set other than VM_EXEC will exit the
function without releasing the mmap_write_lock.

Just do the sanity check before the lock is acquired.  This doesn't fix an
actual issue since no caller sets a flag other than VM_EXEC.

Link: https://lkml.kernel.org/r/20230929171937.work.697-kees@kernel.org
Fixes: 2e7ce7d3 ("mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap()")
Signed-off-by: Sebastian Ott <sebott@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The two users of mbind_range() are expecting that mbind_range() will
update the pointer to the previous VMA, or return an error.  However,
set_mempolicy_home_node() does not call mbind_range() if there is no VMA
policy.  The fix is to update the pointer to the previous VMA prior to
continuing iterating the VMAs when there is no policy.

Users may experience a WARN_ON() during VMA policy updates when updating
a range of VMAs on the home node.

Link: https://lkml.kernel.org/r/20230928172432.2246534-1-Liam.Howlett@oracle.com
Link: https://lore.kernel.org/linux-mm/CALcu4rbT+fMVNaO_F2izaCT+e7jzcAciFkOvk21HGJsmLcUuwQ@mail.gmail.com/
Fixes: f4e9e0e6 ("mm/mempolicy: fix use-after-free of VMA iterator")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Yikebaer Aizezi <yikebaer61@gmail.com>
Closes: https://lore.kernel.org/linux-mm/CALcu4rbT+fMVNaO_F2izaCT+e7jzcAciFkOvk21HGJsmLcUuwQ@mail.gmail.com/Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When guard page debug is enabled and set_page_guard returns success, we
miss to forward page to point to start of next split range and we will do
split unexpectedly in page range without target page.  Move start page
update before set_page_guard to fix this.

As we split to wrong target page, then splited pages are not able to merge
back to original order when target page is put back and splited pages
except target page is not usable.  To be specific:

Consider target page is the third page in buddy page with order 2.
| buddy-2 | Page | Target | Page |

After break down to target page, we will only set first page to Guard
because of bug.
| Guard   | Page | Target | Page |

When we try put_page_back_buddy with target page, the buddy page of target
if neither guard nor buddy, Then it's not able to construct original page
with order 2
| Guard | Page | buddy-0 | Page |

All pages except target page is not in free list and is not usable.

Link: https://lkml.kernel.org/r/20230927094401.68205-1-shikemeng@huaweicloud.com
Fixes: 06be6ff3 ("mm,hwpoison: rework soft offline for free pages")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Merge tag 'kbuild-fixes-v6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Fix the module compression with xz so the in-kernel decompressor
   works

 - Document a kconfig idiom to express an optional dependency between
   modules

 - Make modpost, when W=1 is given, detect broken drivers that reference
   .exit.* sections

 - Remove unused code

* tag 'kbuild-fixes-v6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: remove stale code for 'source' symlink in packaging scripts
  modpost: Don't let "driver"s reference .exit.*
  vmlinux.lds.h: remove unused CPU_KEEP and CPU_DISCARD macros
  modpost: add missing else to the "of" check
  Documentation: kbuild: explain handling optional dependencies
  kbuild: Use CRC32 and a 1MiB dictionary for XZ compressed modules

Merge tag 'mm-hotfixes-stable-2023-10-01-08-34' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Fourteen hotfixes, eleven of which are cc:stable. The remainder
  pertain to issues which were introduced after 6.5"

* tag 'mm-hotfixes-stable-2023-10-01-08-34' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  Crash: add lock to serialize crash hotplug handling
  selftests/mm: fix awk usage in charge_reserved_hugetlb.sh and hugetlb_reparenting_test.sh that may cause error
  mm: mempolicy: keep VMA walk if both MPOL_MF_STRICT and MPOL_MF_MOVE are specified
  mm/damon/vaddr-test: fix memory leak in damon_do_test_apply_three_regions()
  mm, memcg: reconsider kmem.limit_in_bytes deprecation
  mm: zswap: fix potential memory corruption on duplicate store
  arm64: hugetlb: fix set_huge_pte_at() to work with all swap entries
  mm: hugetlb: add huge page size param to set_huge_pte_at()
  maple_tree: add MAS_UNDERFLOW and MAS_OVERFLOW states
  maple_tree: add mas_is_active() to detect in-tree walks
  nilfs2: fix potential use after free in nilfs_gccache_submit_read_data()
  mm: abstract moving to the next PFN
  mm: report success more often from filemap_map_folio_range()
  fs: binfmt_elf_efpic: fix personality for ELF-FDPIC

Pull misc driver fix from Greg KH:
 "Here is a single, much requested, fix for a set of misc drivers to
  resolve a much reported regression in the -rc series that has also
  propagated back to the stable releases. Sorry for the delay, lots of
  conference travel for a few weeks put me very far behind in patch
  wrangling.

  It has been reported by many to resolve the reported problem, and has
  been in linux-next with no reported issues"

* tag 'char-misc-6.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  misc: rtsx: Fix some platforms can not boot and move the l1ss judgment to probe

Pull tty / serial driver fixes from Greg KH:
 "Here are two tty/serial driver fixes for 6.6-rc4 that resolve some
  reported regressions:

   - revert a n_gsm change that ended up causing problems

   - 8250_port fix for irq data

  both have been in linux-next for over a week with no reported
  problems"

* tag 'tty-6.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "tty: n_gsm: fix UAF in gsm_cleanup_mux"
  serial: 8250_port: Check IRQ data before use

Pull x86 fixes from Ingo Molnar:
 "Misc fixes: a kerneldoc build warning fix, add SRSO mitigation for
  AMD-derived Hygon processors, and fix a SGX kernel crash in the page
  fault handler that can trigger when ksgxd races to reclaim the SECS
  special page, by making the SECS page unswappable"

* tag 'x86-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sgx: Resolves SECS reclaim vs. page fault for EAUG race
  x86/srso: Add SRSO mitigation for Hygon processors
  x86/kgdb: Fix a kerneldoc warning when build with W=1

Pull timer fix from Ingo Molnar:
 "Fix a spurious kernel warning during CPU hotplug events that may
  trigger when timer/hrtimer softirqs are pending, which are otherwise
  hotplug-safe and don't merit a warning"

* tag 'timers-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers: Tag (hr)timer softirq as hotplug safe

Pull scheduler fix from Ingo Molnar:
 "Fix a RT tasks related lockup/live-lock during CPU offlining"

* tag 'sched-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Fix live lock between select_fallback_rq() and RT push

Pull perf event fixes from Ingo Molnar:
 "Misc fixes: work around an AMD microcode bug on certain models, and
  fix kexec kernel PMI handlers on AMD systems that get loaded on older
  kernels that have an unexpected register state"

* tag 'perf-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/amd: Do not WARN() on every IRQ
  perf/x86/amd/core: Fix overflow reset on hotplug

Since commit d8131c29 ("kbuild: remove $(MODLIB)/source symlink"),
modules_install does not create the 'source' symlink.

Remove the stale code from builddeb and kernel.spec.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Drivers must not reference functions marked with __exit as these likely
are not available when the code is built-in.

There are few creative offenders uncovered for example in ARCH=amd64
allmodconfig builds. So only trigger the section mismatch warning for
W=1 builds.

The dual rule that drivers must not reference .init.* is implemented
since commit 0db25245 ("modpost: don't allow *driver to reference
.init.*") which however missed that .exit.* should be handled in the
same way.

Thanks to Masahiro Yamada and Arnd Bergmann who gave valuable hints to
find this improvement.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Remove the left-over of commit e24f6628 ("modpost: remove all
traces of cpuinit/cpuexit sections").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Paul Gortmaker <paul.gortmaker@windriver.com>

Without this 'else' statement, an "usb" name goes into two handlers:
the first/previous 'if' statement _AND_ the for-loop over 'devtable',
but the latter is useless as it has no 'usb' device_id entry anyway.

Tested with allmodconfig before/after patch; no changes to *.mod.c:

    git checkout v6.6-rc3
    make -j$(nproc) allmodconfig
    make -j$(nproc) olddefconfig

    make -j$(nproc)
    find . -name '*.mod.c' | cpio -pd /tmp/before

    # apply patch

    make -j$(nproc)
    find . -name '*.mod.c' | cpio -pd /tmp/after

    diff -r /tmp/before/ /tmp/after/
    # no difference

Fixes: acbef7b7 ("modpost: fix module autoloading for OF devices with generic compatible property")
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Pull ARM SoC fixes from Arnd Bergmann:
 "These are the latest bug fixes that have come up in the soc tree. Most
  of these are fairly minor. Most notably, the majority of changes this
  time are not for dts files as usual.

   - Updates to the addresses of the broadcom and aspeed entries in the
     MAINTAINERS file.

   - Defconfig updates to address a regression on samsung and a build
     warning from an unknown Kconfig symbol

   - Build fixes for the StrongARM and Uniphier platforms

   - Code fixes for SCMI and FF-A firmware drivers, both of which had a
     simple bug that resulted in invalid data, and a lesser fix for the
     optee firmware driver

   - Multiple fixes for the recently added loongson/loongarch "guts" soc
     driver

   - Devicetree fixes for RISC-V on the startfive platform, addressing
     issues with NOR flash, usb and uart.

   - Multiple fixes for NXP i.MX8/i.MX9 dts files, fixing problems with
     clock, gpio, hdmi settings and the Makefile

   - Bug fixes for i.MX firmware code and the OCOTP soc driver

   - Multiple fixes for the TI sysc bus driver

   - Minor dts updates for TI omap dts files, to address boot time
     warnings and errors"

* tag 'soc-fixes-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (35 commits)
  MAINTAINERS: Fix Florian Fainelli's email address
  arm64: defconfig: enable syscon-poweroff driver
  ARM: locomo: fix locomolcd_power declaration
  soc: loongson: loongson2_guts: Remove unneeded semicolon
  soc: loongson: loongson2_guts: Convert to devm_platform_ioremap_resource()
  soc: loongson: loongson_pm2: Populate children syscon nodes
  dt-bindings: soc: loongson,ls2k-pmc: Allow syscon-reboot/syscon-poweroff as child
  soc: loongson: loongson_pm2: Drop useless of_device_id compatible
  dt-bindings: soc: loongson,ls2k-pmc: Use fallbacks for ls2k-pmc compatible
  soc: loongson: loongson_pm2: Add dependency for INPUT
  arm64: defconfig: remove CONFIG_COMMON_CLK_NPCM8XX=y
  ARM: uniphier: fix cache kernel-doc warnings
  MAINTAINERS: aspeed: Update Andrew's email address
  MAINTAINERS: aspeed: Update git tree URL
  firmware: arm_ffa: Don't set the memory region attributes for MEM_LEND
  arm64: dts: imx: Add imx8mm-prt8mm.dtb to build
  arm64: dts: imx8mm-evk: Fix hdmi@3d node
  soc: imx8m: Enable OCOTP clock for imx8mm before reading registers
  arm64: dts: imx8mp-beacon-kit: Fix audio_pll2 clock
  arm64: dts: imx8mp: Fix SDMA2/3 clocks
  ...

Pull tracing fixes from Steven Rostedt:

 - Make sure 32-bit applications using user events have aligned access
   when running on a 64-bit kernel.

 - Add cond_resched in the loop that handles converting enums in
   print_fmt string is trace events.

 - Fix premature wake ups of polling processes in the tracing ring
   buffer. When a task polls waiting for a percentage of the ring buffer
   to be filled, the writer still will wake it up at every event. Add
   the polling's percentage to the "shortest_full" list to tell the
   writer when to wake it up.

 - For eventfs dir lookups on dynamic events, an event system's only
   event could be removed, leaving its dentry with no children. This is
   totally legitimate. But in eventfs_release() it must not access the
   children array, as it is only allocated when the dentry has children.

* tag 'trace-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  eventfs: Test for dentries array allocated in eventfs_release()
  tracing/user_events: Align set_bit() address for all archs
  tracing: relax trace_event_eval_update() execution with cond_resched()
  ring-buffer: Update "shortest_full" in polling

The dcache_dir_open_wrapper() could be called when a dynamic event is
being deleted leaving a dentry with no children. In this case the
dlist->dentries array will never be allocated. This needs to be checked
for in eventfs_release(), otherwise it will trigger a NULL pointer
dereference.

Link: https://lore.kernel.org/linux-trace-kernel/20230930090106.1c3164e9@rorschach.local.home

Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Fixes: ef36b4f9 ("eventfs: Remember what dentries were created on dir open")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

All architectures should use a long aligned address passed to set_bit().
User processes can pass either a 32-bit or 64-bit sized value to be
updated when tracing is enabled when on a 64-bit kernel. Both cases are
ensured to be naturally aligned, however, that is not enough. The
address must be long aligned without affecting checks on the value
within the user process which require different adjustments for the bit
for little and big endian CPUs.

Add a compat flag to user_event_enabler that indicates when a 32-bit
value is being used on a 64-bit kernel. Long align addresses and correct
the bit to be used by set_bit() to account for this alignment. Ensure
compat flags are copied during forks and used during deletion clears.

Link: https://lore.kernel.org/linux-trace-kernel/20230925230829.341-2-beaub@linux.microsoft.com
Link: https://lore.kernel.org/linux-trace-kernel/20230914131102.179100-1-cleger@rivosinc.com/

Cc: stable@vger.kernel.org
Fixes: 72357590 ("tracing/user_events: Use remote writes for event enablement")
Reported-by: Clément Léger <cleger@rivosinc.com>
Suggested-by: Clément Léger <cleger@rivosinc.com>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

When kernel is compiled without preemption, the eval_map_work_func()
(which calls trace_event_eval_update()) will not be preempted up to its
complete execution. This can actually cause a problem since if another
CPU call stop_machine(), the call will have to wait for the
eval_map_work_func() function to finish executing in the workqueue
before being able to be scheduled. This problem was observe on a SMP
system at boot time, when the CPU calling the initcalls executed
clocksource_done_booting() which in the end calls stop_machine(). We
observed a 1 second delay because one CPU was executing
eval_map_work_func() and was not preempted by the stop_machine() task.

Adding a call to cond_resched() in trace_event_eval_update() allows
other tasks to be executed and thus continue working asynchronously
like before without blocking any pending task at boot time.

Link: https://lore.kernel.org/linux-trace-kernel/20230929191637.416931-1-cleger@rivosinc.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

It was discovered that the ring buffer polling was incorrectly stating
that read would not block, but that's because polling did not take into
account that reads will block if the "buffer-percent" was set. Instead,
the ring buffer polling would say reads would not block if there was any
data in the ring buffer. This was incorrect behavior from a user space
point of view. This was fixed by commit 42fb0a1e by having the polling
code check if the ring buffer had more data than what the user specified
"buffer percent" had.

The problem now is that the polling code did not register itself to the
writer that it wanted to wait for a specific "full" value of the ring
buffer. The result was that the writer would wake the polling waiter
whenever there was a new event. The polling waiter would then wake up, see
that there's not enough data in the ring buffer to notify user space and
then go back to sleep. The next event would wake it up again.

Before the polling fix was added, the code would wake up around 100 times
for a hackbench 30 benchmark. After the "fix", due to the constant waking
of the writer, it would wake up over 11,0000 times! It would never leave
the kernel, so the user space behavior was still "correct", but this
definitely is not the desired effect.

To fix this, have the polling code add what it's waiting for to the
"shortest_full" variable, to tell the writer not to wake it up if the
buffer is not as full as it expects to be.

Note, after this fix, it appears that the waiter is now woken up around 2x
the times it was before (~200). This is a tremendous improvement from the
11,000 times, but I will need to spend some time to see why polling is
more aggressive in its wakeups than the read blocking code.

Link: https://lore.kernel.org/linux-trace-kernel/20230929180113.01c2cae3@rorschach.local.home

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: 42fb0a1e ("tracing/ring-buffer: Have polling block on watermark")
Reported-by: Julia Lawall <julia.lawall@inria.fr>
Tested-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Pull dma-mapping fixes from Christoph Hellwig:

 - fix the narea calculation in swiotlb initialization (Ross Lagerwall)

 - fix the check whether a device has used swiotlb (Petr Tesarik)

* tag 'dma-mapping-6.6-2023-09-30' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: fix the check whether a device has used software IO TLB
  swiotlb: use the calculated number of areas

Pull iomap fixes from Darrick Wong:

 - Handle a race between writing and shrinking block devices by
   returning EIO

 - Fix a typo in a comment

* tag 'iomap-6.6-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: Spelling s/preceeding/preceding/g
  iomap: add a workaround for racy i_size updates on block devices

Pull i2c fixes from Wolfram Sang:
 "Usual business: a driver fix, a DT fix, a minor core fix"

* tag 'i2c-for-6.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: npcm7xx: Fix callback completion ordering
  i2c: mux: Avoid potential false error message in i2c_mux_add_adapter
  dt-bindings: i2c: mxs: Pass ref and 'unevaluatedProperties: false'

Pull ACPI fix from Rafael Wysocki:
 "Fix a possible NULL pointer dereference in the error path of
  acpi_video_bus_add() resulting from recent changes (Dinghao Liu)"

* tag 'acpi-6.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: video: Fix NULL pointer dereference in acpi_video_bus_add()

Pull powerpc fixes from Michael Ellerman:

 - Fix arch_stack_walk_reliable(), used by live patching

 - Fix powerpc selftests to work with run_kselftest.sh

Thanks to Joe Lawrence and Petr Mladek.

* tag 'powerpc-6.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  selftests/powerpc: Fix emit_tests to work with run_kselftest.sh
  powerpc/stacktrace: Fix arch_stack_walk_reliable()

Pull nfsd fix from Chuck Lever:

 - Fix NFSv4 READ corner case

* tag 'nfsd-6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: Fix zero NFSv4 READ results when RQ_SPLICE_OK is not set

Pull smb client fix from Steve French:
 "Fix for password freeing potential oops (also for stable)"

* tag '6.6-rc3-smb3-client-fix' of git://git.samba.org/sfrench/cifs-2.6:
  fs/smb/client: Reset password pointer to NULL