Al Viro [Sat, 6 Dec 2025 18:01:06 +0000 (13:01 -0500)]
namei.c: switch user pathname imports to CLASS(filename{,_flags})
filename_flags is used by user_path_at(). I suspect that mixing
LOOKUP_EMPTY with real lookup flags had been a mistake all along; the
former belongs to pathname import, the latter - to pathwalk. Right now
none of the remaining in-tree callers of user_path_at() are getting
LOOKUP_EMPTY in flags, so user_path_at() could probably be switched
to CLASS(filename)...
Al Viro [Wed, 7 Jan 2026 04:19:10 +0000 (23:19 -0500)]
non-consuming variant of do_renameat2()
filename_renameat2() replaces do_renameat2(); unlike the latter,
it does not drop filename references - these days it can be just
as easily arranged in the caller.
Al Viro [Tue, 28 Oct 2025 06:29:04 +0000 (02:29 -0400)]
switch {alloc,free}_bprm() to CLASS()
All linux_binprm instances come from alloc_bprm() and are unconditionally
destroyed by free_bprm() in the end of the same scope. IOW, CLASS()
machinery is a decent fit for those.
Al Viro [Wed, 7 Jan 2026 20:16:24 +0000 (15:16 -0500)]
execve: fold {compat_,}do_execve{,at}() into their sole callers
All of them are wrappers for do_execveat_common() and each has
exactly one caller. The only difference is in the way they are
constructing argv/envp arguments for do_execveat_common() and
that's easy to do with less boilerplate.
Al Viro [Thu, 25 Sep 2025 21:11:36 +0000 (17:11 -0400)]
simplify the callers of file_open_name()
It accepts ERR_PTR() for name and does the right thing in that case.
That allows to simplify the logics in callers, making them trivial
to switch to CLASS(filename).
Al Viro [Tue, 28 Oct 2025 04:11:45 +0000 (00:11 -0400)]
rename do_filp_open() to do_file_open()
"filp" thing never made sense; seeing that there are exactly 4 callers
in the entire tree (and it's neither exported nor even declared in
linux/*/*.h), there's no point keeping that ugliness.
FWIW, the 'filp' thing did originate in OSD&I; for some reason Tanenbaum
decided to call the object representing an opened file 'struct filp',
the last letter standing for 'position'. In all Unices, Linux included,
the corresponding object had always been 'struct file'...
Al Viro [Thu, 25 Sep 2025 21:02:28 +0000 (17:02 -0400)]
do_filp_open(): DTRT when getting ERR_PTR() as pathname
The rest of the set_nameidata() callers treat IS_ERR(pathname) as
"bail out immediately with PTR_ERR(pathname) as error". Makes
life simpler for callers; do_filp_open() is the only exception
and its callers would also benefit from such calling conventions
change.
Al Viro [Sun, 2 Nov 2025 05:01:47 +0000 (01:01 -0400)]
struct filename ->refcnt doesn't need to be atomic
... or visible outside of audit, really. Note that references
held in delayed_filename always have refcount 1, and from the
moment of complete_getname() or equivalent point in getname...()
there won't be any references to struct filename instance left
in places visible to other threads.
Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro [Sun, 2 Nov 2025 00:29:06 +0000 (20:29 -0400)]
allow incomplete imports of filenames
There are two filename-related problems in io_uring and its
interplay with audit.
Filenames are imported when request is submitted and used when
it is processed. Unfortunately, the latter may very well
happen in a different thread. In that case the reference to
filename is put into the wrong audit_context - that of submitting
thread, not the processing one. Audit logics is called by
the latter, and it really wants to be able to find the names
in audit_context current (== processing) thread.
Another related problem is the headache with refcounts -
normally all references to given struct filename are visible
only to one thread (the one that uses that struct filename).
io_uring violates that - an extra reference is stashed in
audit_context of submitter. It gets dropped when submitter
returns to userland, which can happen simultaneously with
processing thread deciding to drop the reference it got.
We paper over that by making refcount atomic, but that means
pointless headache for everyone.
Solution: the notion of partially imported filenames. Namely,
already copied from userland, but *not* exposed to audit yet.
io_uring can create that in submitter thread, and complete the
import (obtaining the usual reference to struct filename) in
processing thread.
Object: struct delayed_filename.
Primitives for working with it:
delayed_getname(&delayed_filename, user_string) - copies the name from
userland, returning 0 and stashing the address of (still incomplete)
struct filename in delayed_filename on success and returning -E... on
error.
delayed_getname_uflags(&delayed_filename, user_string, atflags) -
similar, in the same relation to delayed_getname() as getname_uflags()
is to getname()
complete_getname(&delayed_filename) - completes the import of filename
stashed in delayed_filename and returns struct filename to caller,
emptying delayed_filename.
CLASS(filename_complete_delayed, name)(&delayed_filename) - variant of
CLASS(filename) with complete_getname() for constructor.
dismiss_delayed_filename(&delayed_filename) - destructor; drops whatever
might be stashed in delayed_filename, emptying it.
putname_to_delayed(&delayed_filename, name) - if name is shared, stashes
its copy into delayed_filename and drops the reference to name, otherwise
stashes the name itself in there.
Al Viro [Thu, 20 Nov 2025 00:45:04 +0000 (19:45 -0500)]
struct filename: saner handling of long names
Always allocate struct filename from names_cachep, long name or short;
short names would be embedded into struct filename. Longer ones do
not cannibalize the original struct filename - put them into kmalloc'ed
buffers (PATH_MAX-sized for import from userland, strlen() + 1 - for
ones originating kernel-side, where we know the length beforehand).
Cutoff length for short names is chosen so that struct filename would be
192 bytes long - that's both a multiple of 64 and large enough to cover
the majority of real-world uses.
Simplifies logics in getname()/putname() and friends.
[fixed an embarrassing braino in EMBEDDED_NAME_MAX, first reported by
Dan Carpenter]
Al Viro [Thu, 20 Nov 2025 00:19:24 +0000 (19:19 -0500)]
struct filename: use names_cachep only for getname() and friends
Instances of struct filename come from names_cachep (via
__getname()). That is done by getname_flags() and getname_kernel()
and these two are the main callers of __getname(). However, there are
other callers that simply want to allocate PATH_MAX bytes for uses that
have nothing to do with struct filename.
We want saner allocation rules for long pathnames, so that struct
filename would *always* come from names_cachep, with the out-of-line
pathname getting kmalloc'ed. For that we need to be able to change the
size of objects allocated by getname_flags()/getname_kernel().
That requires the rest of __getname() users to stop using
names_cachep; we could explicitly switch all of those to kmalloc(),
but that would cause quite a bit of noise. So the plan is to switch
getname_...() to new helpers and turn __getname() into a wrapper for
kmalloc(). Remaining __getname() users could be converted to explicit
kmalloc() at leisure, hopefully along with figuring out what size do
they really want - PATH_MAX is an overkill for some of them, used out
of laziness ("we have a convenient helper that does 4K allocations and
that's large enough, let's use it").
As a side benefit, names_cachep is no longer used outside
of fs/namei.c, so we can move it there and be done with that.
Al Viro [Wed, 19 Nov 2025 22:15:23 +0000 (17:15 -0500)]
getname_flags() massage, part 1
In case of long name don't reread what we'd already copied.
memmove() it instead. That avoids the possibility of ending
up with empty name there and the need to look at the flags
on the slow path.
Al Viro [Wed, 19 Nov 2025 21:15:04 +0000 (16:15 -0500)]
ntfs: ->d_compare() must not block
... so don't use __getname() there. Switch it (and ntfs_d_hash(), while
we are at it) to kmalloc(PATH_MAX, GFP_NOWAIT). Yes, ntfs_d_hash()
almost certainly can do with smaller allocations, but let ntfs folks
deal with that - keep the allocation size as-is for now.
Stop abusing names_cachep in ntfs, period - various uses of that thing
in there have nothing to do with pathnames; just use k[mz]alloc() and
be done with that. For now let's keep sizes as-in, but AFAICS none of
the users actually want PATH_MAX.
Al Viro [Sat, 1 Nov 2025 05:54:52 +0000 (01:54 -0400)]
get rid of audit_reusename()
Originally we tried to avoid multiple insertions into audit names array
during retry loop by a cute hack - memorize the userland pointer and
if there already is a match, just grab an extra reference to it.
Cute as it had been, it had problems - two identical pointers had
audit aux entries merged, two identical strings did not. Having
different behaviour for syscalls that differ only by addresses of
otherwise identical string arguments is obviously wrong - if nothing
else, compiler can decide to merge identical string literals.
Besides, this hack does nothing for non-audited processes - they get
a fresh copy for retry. It's not time-critical, but having behaviour
subtly differ that way is bogus.
These days we have very few places that import filename more than once
(9 functions total) and it's easy to massage them so we get rid of all
re-imports. With that done, we don't need audit_reusename() anymore.
There's no need to memorize userland pointer either.
Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
do_readlinkat(): import pathname only once
Take getname_flags() and putname() outside of retry loop.
Since getname_flags() is the only thing that cares about LOOKUP_EMPTY,
don't bother with setting LOOKUP_EMPTY in lookup_flags - just pass it
to getname_flags() and be done with that.
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
do_sys_truncate(): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
In this case we never pass LOOKUP_EMPTY, so getname_flags() is equivalent
to plain getname().
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
user_statfs(): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
In this case we never pass LOOKUP_EMPTY, so getname_flags() is equivalent
to plain getname().
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
chroot(2): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
In this case we never pass LOOKUP_EMPTY, so getname_flags() is equivalent
to plain getname().
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
chdir(2): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
In this case we never pass LOOKUP_EMPTY, so getname_flags() is equivalent
to plain getname().
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
do_utimes_path(): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
Since we have the default logics for use of LOOKUP_EMPTY (passed iff
AT_EMPTY_PATH is present in flags), just use getname_uflags() and
don't bother with setting LOOKUP_EMPTY in lookup_flags - getname_uflags()
will pass the right thing to getname_flags() and filename_lookup()
doesn't care about LOOKUP_EMPTY at all.
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
do_fchownat(): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
Since we have the default logics for use of LOOKUP_EMPTY (passed iff
AT_EMPTY_PATH is present in flags), just use getname_uflags() and
don't bother with setting LOOKUP_EMPTY in lookup_flags - getname_uflags()
will pass the right thing to getname_flags() and filename_lookup()
doesn't care about LOOKUP_EMPTY at all.
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
do_fchmodat(): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
Since we have the default logics for use of LOOKUP_EMPTY (passed iff
AT_EMPTY_PATH is present in flags), just use getname_uflags() and
don't bother with setting LOOKUP_EMPTY in lookup_flags - getname_uflags()
will pass the right thing to getname_flags() and filename_lookup()
doesn't care about LOOKUP_EMPTY at all.
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
Al Viro [Sat, 1 Nov 2025 04:48:31 +0000 (00:48 -0400)]
do_faccessat(): import pathname only once
Convert the user_path_at() call inside a retry loop into getname_flags() +
filename_lookup() + putname() and leave only filename_lookup() inside
the loop.
Since we have the default logics for use of LOOKUP_EMPTY (passed iff
AT_EMPTY_PATH is present in flags), just use getname_uflags() and
don't bother with setting LOOKUP_EMPTY in lookup_flags - getname_uflags()
will pass the right thing to getname_flags() and filename_lookup()
doesn't care about LOOKUP_EMPTY at all.
The things could be further simplified by use of cleanup.h stuff, but
let's not clutter the patch with that.
"flags" in filename_flags is in LOOKUP_... space, only LOOKUP_EMPTY matters.
"flags" in filename_uflags and filename_maybe_null is in AT_...... space,
and only AT_EMPTY_PATH matters.
filename_flags conventions might be worth reconsidering later (it might or
might not be better off with boolean instead)
Linus Torvalds [Mon, 12 Jan 2026 01:07:56 +0000 (15:07 -1000)]
Merge tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull crypto library fixes from Eric Biggers:
- A couple more fixes for the lib/crypto KUnit tests
- Fix missing MMU protection for the AES S-box
* tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
lib/crypto: aes: Fix missing MMU protection for AES S-box
MAINTAINERS: add test vector generation scripts to "CRYPTO LIBRARY"
lib/crypto: tests: Fix syntax error for old python versions
lib/crypto: tests: polyval_kunit: Increase iterations for preparekey in IRQs
Linus Torvalds [Sun, 11 Jan 2026 17:27:44 +0000 (07:27 -1000)]
Merge tag 'char-misc-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are some small char/misc driver fixes for some reported issues.
Included in here is:
- much reported rust_binder fix
- counter driver fixes
- new device ids for the mei driver
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
rust_binder: remove spin_lock() in rust_shrink_free_page()
mei: me: add nova lake point S DID
counter: 104-quad-8: Fix incorrect return value in IRQ handler
counter: interrupt-cnt: Drop IRQF_NO_THREAD flag
Linus Torvalds [Sun, 11 Jan 2026 17:11:53 +0000 (07:11 -1000)]
Merge tag 'sched-urgent-2026-01-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Ingo Molnar:
"Fix a crash in sched_mm_cid_after_execve()"
* tag 'sched-urgent-2026-01-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/mm_cid: Prevent NULL mm dereference in sched_mm_cid_after_execve()
Linus Torvalds [Sun, 11 Jan 2026 16:36:20 +0000 (06:36 -1000)]
Merge tag 'irq-urgent-2026-01-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc irqchip fixes from Ingo Molnar:
- Fix an endianness bug in the gic-v5 irqchip driver
- Revert a broken commit from the riscv-imsic irqchip driver
* tag 'irq-urgent-2026-01-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "irqchip/riscv-imsic: Embed the vector array in lpriv"
irqchip/gic-v5: Fix gicv5_its_map_event() ITTE read endianness
Linus Torvalds [Sun, 11 Jan 2026 01:54:41 +0000 (15:54 -1000)]
Merge tag 'riscv-for-linus-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Paul Walmsley:
"Notable changes include a fix to close one common microarchitectural
attack vector for out-of-order cores. Another patch exposed an
omission in my boot test coverage, which is currently missing
relocatable kernels. Otherwise, the fixes seem to be settling down for
us.
- Fix CONFIG_RELOCATABLE=y boots by building Image files from
vmlinux, rather than vmlinux.unstripped, now that the .modinfo
section is included in vmlinux.unstripped
- Prevent branch predictor poisoning microarchitectural attacks that
use the syscall index as a vector by using array_index_nospec() to
clamp the index after the bounds check (as x86 and ARM64 already
do)
- Fix a crash in test_kprobes when building with Clang
- Fix a deadlock possible when tracing is enabled for SBI ecalls
- Fix the definition of the Zk standard RISC-V ISA extension bundle,
which was missing the Zknh extension
- A few other miscellaneous non-functional cleanups, removing unused
macros, fixing an out-of-date path in code comments, resolving a
compile-time warning for a type mismatch in a pr_crit(), and
removing an unnecessary header file inclusion"
* tag 'riscv-for-linus-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: trace: fix snapshot deadlock with sbi ecall
riscv: remove irqflags.h inclusion in asm/bitops.h
riscv: cpu_ops_sbi: smp_processor_id() returns int, not unsigned int
riscv: configs: Clean up references to non-existing configs
riscv: kexec_image: Fix dead link to boot-image-header.rst
riscv: pgtable: Cleanup useless VA_USER_XXX definitions
riscv: cpufeature: Fix Zk bundled extension missing Zknh
riscv: fix KUnit test_kprobes crash when building with Clang
riscv: Sanitize syscall table indexing under speculation
riscv: boot: Always make Image from vmlinux, not vmlinux.unstripped
Linus Torvalds [Sun, 11 Jan 2026 00:57:55 +0000 (14:57 -1000)]
Merge tag 'linux_kselftest-fixes-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest fix from Shuah Khan:
"Fix tracing test_multiple_writes stalls when buffer_size_kb is less
than 12KB"
* tag 'linux_kselftest-fixes-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
selftests/tracing: Fix test_multiple_writes stall
Linus Torvalds [Sat, 10 Jan 2026 17:14:40 +0000 (07:14 -1000)]
Merge tag 'iommu-fixes-v6.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux
Pull iomu fixes from Joerg Roedel:
- several Kconfig-related build fixes
- fix for when gcc 8.5 on PPC refuses to inline a function from a
header file
* tag 'iommu-fixes-v6.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux:
iommupt: Make pt_feature() always_inline
iommufd/selftest: Prevent module/builtin conflicts in kconfig
iommufd/selftest: Add missing kconfig for DMA_SHARED_BUFFER
iommupt: Fix the kunit building
Gao Xiang [Sat, 10 Jan 2026 11:47:03 +0000 (19:47 +0800)]
erofs: fix file-backed mounts no longer working on EROFS partitions
Sheng Yong reported [1] that Android APEX images didn't work with commit 072a7c7cdbea ("erofs: don't bother with s_stack_depth increasing for
now") because "EROFS-formatted APEX file images can be stored within an
EROFS-formatted Android system partition."
In response, I sent a quick fat-fingered [PATCH v3] to address the
report. Unfortunately, the updated condition was incorrect:
The condition `!sb->s_bdev` is always true for all file-backed EROFS
mounts, making the check effectively a no-op.
The real fix tested and confirmed by Sheng Yong [2] at that time was
[PATCH v3 RESEND], which correctly ensures the following EROFS^2 setup
works:
EROFS (on a block device) + EROFS (file-backed mount)
But sadly I screwed it up again by upstreaming the outdated [PATCH v3].
This patch applies the same logic as the delta between the upstream
[PATCH v3] and the real fix [PATCH v3 RESEND].
Jason Gunthorpe [Fri, 9 Jan 2026 14:29:52 +0000 (10:29 -0400)]
iommupt: Make pt_feature() always_inline
gcc 8.5 on powerpc does not automatically inline these functions even
though they evaluate to constants in key cases. Since the constant
propagation is essential for some code elimination and built-time checks
this causes a build failure:
if (pts_feature(&pts, PT_FEAT_DMA_INCOHERENT) &&
!pt_test_sw_bit_acquire(&pts,
SW_BIT_CACHE_FLUSH_DONE))
flush_writes_item(&pts);
Where pts_feature() evaluates to a constant false. Mark them as
__always_inline to force it to evaluate to a constant and trigger the code
elimination.
Fixes: 7c5b184db714 ("genpt: Generic Page Table base API") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202512230720.9y9DtWIo-lkp@intel.com/ Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Jason Gunthorpe [Tue, 6 Jan 2026 19:22:12 +0000 (15:22 -0400)]
iommufd/selftest: Prevent module/builtin conflicts in kconfig
The selftest now depends on the AMDv1 page table, however the selftest
kconfig itself is just an sub-option of the main IOMMUFD module kconfig.
This means it cannot be modular and so kconfig allowed a modular
IOMMU_PT_AMDV1 with a built in IOMMUFD. This causes link failures:
ld: vmlinux.o: in function `mock_domain_alloc_pgtable.isra.0':
selftest.c:(.text+0x12e8ad3): undefined reference to `pt_iommu_amdv1_init'
ld: vmlinux.o: in function `BSWAP_SHUFB_CTL':
sha1-avx2-asm.o:(.rodata+0xaa36a8): undefined reference to `pt_iommu_amdv1_read_and_clear_dirty'
ld: sha1-avx2-asm.o:(.rodata+0xaa36f0): undefined reference to `pt_iommu_amdv1_map_pages'
ld: sha1-avx2-asm.o:(.rodata+0xaa36f8): undefined reference to `pt_iommu_amdv1_unmap_pages'
ld: sha1-avx2-asm.o:(.rodata+0xaa3720): undefined reference to `pt_iommu_amdv1_iova_to_phys'
Adjust the kconfig to disable IOMMUFD_TEST if IOMMU_PT_AMDV1 is incompatible.
Fixes: e93d5945ed5b ("iommufd: Change the selftest to use iommupt instead of xarray") Suggested-by: Arnd Bergmann <arnd@arndb.de> Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202512210135.freQWpxa-lkp@intel.com/ Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Jason Gunthorpe [Tue, 6 Jan 2026 19:22:11 +0000 (15:22 -0400)]
iommufd/selftest: Add missing kconfig for DMA_SHARED_BUFFER
The test doesn't build without it, dma-buf.h does not provide stub
functions if it is not enabled. Compilation can fail with:
ERROR:root:ld: vmlinux.o: in function `iommufd_test':
(.text+0x3b1cdd): undefined reference to `dma_buf_get'
ld: (.text+0x3b1d08): undefined reference to `dma_buf_put'
ld: (.text+0x3b2105): undefined reference to `dma_buf_export'
ld: (.text+0x3b211f): undefined reference to `dma_buf_fd'
ld: (.text+0x3b2e47): undefined reference to `dma_buf_move_notify'
Add the missing select.
Fixes: d2041f1f11dd ("iommufd/selftest: Add some tests for the dmabuf flow") Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Jason Gunthorpe [Tue, 6 Jan 2026 19:22:10 +0000 (15:22 -0400)]
iommupt: Fix the kunit building
The kunit doesn't work since the below commit made GENERIC_PT
unselectable:
$ make ARCH=x86_64 O=build_kunit_x86_64 olddefconfig
ERROR:root:Not all Kconfig options selected in kunitconfig were in the generated .config.
This is probably due to unsatisfied dependencies.
Missing: CONFIG_DEBUG_GENERIC_PT=y, CONFIG_IOMMUFD_TEST=y,
CONFIG_IOMMU_PT_X86_64=y, CONFIG_GENERIC_PT=y, CONFIG_IOMMU_PT_AMDV1=y,
CONFIG_IOMMU_PT_VTDSS=y, CONFIG_IOMMU_PT=y, CONFIG_IOMMU_PT_KUNIT_TEST=y
Also remove the unneeded CONFIG_IOMMUFD_TEST reference as the iommupt kunit
doesn't interact with iommufd, and it doesn't currently build for the
kunit due problems with DMA_SHARED buffer either.
Fixes: 01569c216dde ("genpt: Make GENERIC_PT invisible") Fixes: 1dd4187f53c3 ("iommupt: Add a kunit test for Generic Page Table") Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Linus Torvalds [Sat, 10 Jan 2026 05:34:50 +0000 (19:34 -1000)]
Merge tag 'erofs-for-6.19-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fix from Gao Xiang:
- Don't increase s_stack_depth which caused regressions in some
composefs mount setups (EROFS + ovl^2)
Instead just allow one extra unaccounted fs stacking level for
straightforward cases.
* tag 'erofs-for-6.19-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: don't bother with s_stack_depth increasing for now
Gao Xiang [Thu, 8 Jan 2026 02:38:31 +0000 (10:38 +0800)]
erofs: don't bother with s_stack_depth increasing for now
Previously, commit d53cd891f0e4 ("erofs: limit the level of fs stacking
for file-backed mounts") bumped `s_stack_depth` by one to avoid kernel
stack overflow when stacking an unlimited number of EROFS on top of
each other.
This fix breaks composefs mounts, which need EROFS+ovl^2 sometimes
(and such setups are already used in production for quite a long time).
One way to fix this regression is to bump FILESYSTEM_MAX_STACK_DEPTH
from 2 to 3, but proving that this is safe in general is a high bar.
After a long discussion on GitHub issues [1] about possible solutions,
one conclusion is that there is no need to support nesting file-backed
EROFS mounts on stacked filesystems, because there is always the option
to use loopback devices as a fallback.
As a quick fix for the composefs regression for this cycle, instead of
bumping `s_stack_depth` for file backed EROFS mounts, we disallow
nesting file-backed EROFS over EROFS and over filesystems with
`s_stack_depth` > 0.
This works for all known file-backed mount use cases (composefs,
containerd, and Android APEX for some Android vendors), and the fix is
self-contained.
Essentially, we are allowing one extra unaccounted fs stacking level of
EROFS below stacking filesystems, but EROFS can only be used in the read
path (i.e. overlayfs lower layers), which typically has much lower stack
usage than the write path.
We can consider increasing FILESYSTEM_MAX_STACK_DEPTH later, after more
stack usage analysis or using alternative approaches, such as splitting
the `s_stack_depth` limitation according to different combinations of
stacking.
Linus Torvalds [Sat, 10 Jan 2026 01:42:46 +0000 (15:42 -1000)]
Merge tag 'block-6.19-20260109' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block fixes from Jens Axboe:
- Kill unlikely checks for blk-rq-qos. These checks are really
all-or-nothing, either the branch is taken all the time, or it's not.
Depending on the configuration, either one of those cases may be
true. Just remove the annotation
- Fix for merging bios with different app tags set
- Fix for a recently introduced slowdown due to RCU synchronization
- Fix for a status change on loop while it's in use, and then a later
fix for that fix
- Fix for the async partition scanning in ublk
* tag 'block-6.19-20260109' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
ublk: fix use-after-free in ublk_partition_scan_work
blk-mq: avoid stall during boot due to synchronize_rcu_expedited
loop: add missing bd_abort_claiming in loop_set_status
block: don't merge bios with different app_tags
blk-rq-qos: Remove unlikely() hints from QoS checks
loop: don't change loop device under exclusive opener in loop_set_status
Linus Torvalds [Sat, 10 Jan 2026 01:21:15 +0000 (15:21 -1000)]
Merge tag 'io_uring-6.19-20260109' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull io_uring fixes from Jens Axboe:
"A single fix for a regression introduced in 6.15, where a failure to
wake up idle io-wq workers at ring exit will wait for the timeout to
expire.
This isn't normally noticeable, as the exit is async.
But if a parent task created a thread that sets up a ring and uses
requests that cause io-wq threads to be created, and the parent task
then waits for the thread to exit, then it can take 5 seconds for that
pthread_join() to succeed as the child thread is waiting for its
children to exit.
On top of that, just a basic cleanup as well"
* tag 'io_uring-6.19-20260109' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
io_uring/io-wq: remove io_wq_for_each_worker() return value
io_uring/io-wq: fix incorrect io_wq_for_each_worker() termination logic
Linus Torvalds [Sat, 10 Jan 2026 01:17:48 +0000 (15:17 -1000)]
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Do not return false if !preemptible() in current_in_efi(). EFI
runtime services can now run with preemption enabled
- Fix uninitialised variable in the arm MPAM driver, reported by sparse
- Fix partial kasan_reset_tag() use in change_memory_common() when
calculating page indices or comparing ranges
- Save/restore TCR2_EL1 during suspend/resume, otherwise the E0POE bit
is lost
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Fix cleared E0POE bit after cpu_suspend()/resume()
arm64: mm: Fix incomplete tag reset in change_memory_common()
arm_mpam: Stop using uninitialized variables in __ris_msmon_read()
arm64/efi: Don't fail check current_in_efi() if preemptible
Linus Torvalds [Sat, 10 Jan 2026 01:05:19 +0000 (15:05 -1000)]
Merge tag 'ceph-for-6.19-rc5' of https://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
"A bunch of libceph fixes split evenly between memory safety and
implementation correctness issues (all marked for stable) and a change
in maintainers for CephFS: Slava and Alex have formally taken over
Xiubo's role"
* tag 'ceph-for-6.19-rc5' of https://github.com/ceph/ceph-client:
libceph: make calc_target() set t->paused, not just clear it
libceph: reset sparse-read state in osd_fault()
libceph: return the handler error from mon_handle_auth_done()
libceph: make free_choose_arg_map() resilient to partial allocation
ceph: update co-maintainers list in MAINTAINERS
libceph: replace overzealous BUG_ON in osdmap_apply_incremental()
libceph: prevent potential out-of-bounds reads in handle_auth_done()
Fushuai Wang [Fri, 9 Jan 2026 03:36:20 +0000 (11:36 +0800)]
selftests/tracing: Fix test_multiple_writes stall
When /sys/kernel/tracing/buffer_size_kb is less than 12KB,
the test_multiple_writes test will stall and wait for more
input due to insufficient buffer space.
Check current buffer_size_kb value before the test. If it is
less than 12KB, it temporarily increase the buffer to 12KB,
and restore the original value after the tests are completed.
Link: https://lore.kernel.org/r/20260109033620.25727-1-fushuai.wang@linux.dev Fixes: 37f46601383a ("selftests/tracing: Add basic test for trace_marker_raw file") Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Fushuai Wang <wangfushuai@baidu.com> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Linus Torvalds [Fri, 9 Jan 2026 17:02:38 +0000 (07:02 -1000)]
Merge tag 'for-6.19-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- fix potential NULL pointer dereference when replaying tree log after
an error
- release path before initializing extent tree to avoid potential
deadlock when allocating new inode
- on filesystems with block size > page size
- fix potential read out of bounds during encoded read of an inline
extent
- only enforce free space tree if v1 cache is required
- print correct tree id in error message
* tag 'for-6.19-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: show correct warning if can't read data reloc tree
btrfs: fix NULL pointer dereference in do_abort_log_replay()
btrfs: force free space tree for bs > ps cases
btrfs: only enforce free space tree if v1 cache is required for bs < ps cases
btrfs: release path before initializing extent tree in btrfs_read_locked_inode()
btrfs: avoid access-beyond-folio for bs > ps encoded writes
Linus Torvalds [Fri, 9 Jan 2026 16:41:10 +0000 (06:41 -1000)]
Merge tag 'pci-v6.19-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull PCI fixes from Bjorn Helgaas:
- Remove ASPM L0s support for MSM8996 SoC since we now enable L0s when
advertised, and it caused random hangs on this device (Manivannan
Sadhasivam)
- Fix meson-pcie to report that the link is up while in ASPM L0s or L1,
since those are active states from the software point of view, and
treating the link as down caused config access failures (Bjorn
Helgaas)
- Fix up sparc DTS BAR descriptions that are above 4GB but not marked
as prefetchable, which caused resource assignment and driver probe
failures after we converted from the SPARC pcibios_enable_device() to
the generic version (Ilpo Järvinen)
* tag 'pci-v6.19-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
sparc/PCI: Correct 64-bit non-pref -> pref BAR resources
PCI: meson: Report that link is up while in ASPM L0s and L1 states
PCI: qcom: Remove ASPM L0s support for MSM8996 SoC
Linus Torvalds [Fri, 9 Jan 2026 16:20:15 +0000 (06:20 -1000)]
Merge tag 'acpi-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI support fix from Rafael Wysocki:
"This fixes the ACPI/PCI legacy interrupts (INTx) parsing in the case
when the ACPI Global System Interrupt (GSI) value is a 32-bit one with
the MSB set.
That was interpreted as a negative integer and caused
acpi_pci_link_allocate_irq() to fail and acpi_irq_get_penalty() to
trigger an out-of-bounds array dereference (Lorenzo Pieralisi)"
* tag 'acpi-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: PCI: IRQ: Fix INTx GSIs signedness
Linus Torvalds [Fri, 9 Jan 2026 16:18:05 +0000 (06:18 -1000)]
Merge tag 'pm-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"This fixes a crash in the hibernation image saving code that can be
triggered when the given compression algorithm is unavailable (Malaya
Kumar Rout)"
* tag 'pm-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: hibernate: Fix crash when freeing invalid crypto compressor
Linus Torvalds [Fri, 9 Jan 2026 16:10:22 +0000 (06:10 -1000)]
Merge tag 'gpio-fixes-for-v6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio fixes from Bartosz Golaszewski:
"There are several ordinary driver fixes and a fix to a race between
the registration of two chips that causes a crash in GPIO core.
The bulk of the changed lines however, concerns the management of
shared GPIOs that landed in v6.19-rc1. Enabling it for ARCH_QCOM
enabled it in defconfig which effectively enabled it for all arm64
platforms and exposed the code to quite a lot of testing (which is
good, right? :)).
As a resukt, I received a number of bug reports, which I progressively
fixed over the course of last weeks. This explains the number of lines
higher than what I normally aim for at this stage.
- balance superio enter/exit calls in error path in gpio-it87
- fix a race where we try to take the SRCU read lock of the GPIO
device before it's been initialized causing a NULL-pointer
dereference
- fix handling of short-pulse interrupts in gpio-pca053x
- fix a reference leak in error path in gpio-mpsse
- mark the GPIO controller as sleeping (it calls sleeping functions)
in gpio-rockchip
- fix several issues in management of shared GPIOs"
* tag 'gpio-fixes-for-v6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio: shared: fix a false-positive sharing detection with reset-gpios
gpiolib: fix lookup table matching
gpio: shared: don't allocate the lookup table until we really need it
gpio: shared: fix a race condition
gpio: shared: assign the correct firmware node for reset-gpio use-case
gpio: rockchip: mark the GPIO controller as sleeping
gpio: mpsse: fix reference leak in gpio_mpsse_probe() error paths
gpio: pca953x: handle short interrupt pulses on PCAL devices
gpiolib: fix race condition for gdev->srcu
gpio: shared: allow sharing a reset-gpios pin between reset-gpio and gpiolib
gpio: shared: verify con_id when adding proxy lookup
gpiolib: allow multiple lookup tables per consumer
gpio: it87: balance superio enter/exit calls in error path
Linus Torvalds [Fri, 9 Jan 2026 16:04:05 +0000 (06:04 -1000)]
Merge tag 'drm-fixes-2026-01-09' of https://gitlab.freedesktop.org/drm/kernel
Pull drm fixes from Dave Airlie:
"I missed the drm-rust fixes tree for last week, so this catches up on
that, along with amdgpu, and then some misc fixes across a few
drivers. I hadn't got an xe pull by the time I sent this, I suspect
one will arrive 10 mins after, but I don't think there is anything
that can't wait for next week.
Things seem to have picked up a little with people coming back from
holidays,
MAINTAINERS:
- Fix Nova GPU driver git links
- Fix typo in TYR driver entry preventing correct behavior of
scripts/get_maintainer.pl
- Exclude TYR driver from DRM MISC
nova-core:
- Correctly select RUST_FW_LOADER_ABSTRACTIONS to prevent build
errors
- Regenerate nova-core bindgen bindings with '--explicit-padding' to
avoid uninitialized bytes
- Fix length of received GSP messages, due to miscalculated message
payload size
- Regenerate bindings to derive MaybeZeroable
- Use a bindings alias to derive the firmware version
exynos:
- hdmi: replace system_wq with system_percpu_wq
pl111:
- Fix error handling in probe
mediatek/atomic/tidss:
- Fix tidss in another way and revert reordering of pre-enable and
post-disable operations, as it breaks other bridge drivers
nouveau:
- Fix regression from fwsec s/r fix
pci/vga:
- Fix multiple gpu's being reported a 'boot_display'
fb-helper:
- Fix vblank timeout during suspend/reset
amdgpu:
- Clang fixes
- Navi1x PCIe DPM fixes
- Ring reset fixes
- ISP suspend fix
- Analog DC fixes
- VPE fixes
- Mode1 reset fix
radeon:
- Variable sized array fix"
* tag 'drm-fixes-2026-01-09' of https://gitlab.freedesktop.org/drm/kernel: (32 commits)
Reapply "Revert "drm/amd: Skip power ungate during suspend for VPE""
drm/amd/display: Check NULL before calling dac_load_detection
drm/amd/pm: Disable MMIO access during SMU Mode 1 reset
drm/exynos: hdmi: replace use of system_wq with system_percpu_wq
drm/fb-helper: Fix vblank timeout during suspend/reset
PCI/VGA: Don't assume the only VGA device on a system is `boot_vga`
drm/amdgpu: Fix query for VPE block_type and ip_count
drm/amd/display: Add missing encoder setup to DACnEncoderControl
drm/amd/display: Correct color depth for SelectCRTC_Source
drm/amd/amdgpu: Fix SMU warning during isp suspend-resume
drm/amdgpu: always backup and reemit fences
drm/amdgpu: don't reemit ring contents more than once
drm/amd/pm: force send pcie parmater on navi1x
drm/amd/pm: fix wrong pcie parameter on navi1x
drm/radeon: Remove __counted_by from ClockInfoArray.clockInfo[]
drm/amd/display: Reduce number of arguments of dcn30's CalculateWatermarksAndDRAMSpeedChangeSupport()
drm/amd/display: Reduce number of arguments of dcn30's CalculatePrefetchSchedule()
drm/amd/display: Apply e4479aecf658 to dml
nouveau: don't attempt fwsec on sb on newer platforms
drm/tidss: Fix enable/disable order
...
Linus Torvalds [Fri, 9 Jan 2026 15:57:57 +0000 (05:57 -1000)]
Merge tag 'vfs-6.19-rc5.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
- Remove incorrect __user annotation from struct xattr_args::value
- Documentation fix: Add missing kernel-doc description for the @isnew
parameter in ilookup5_nowait() to silence Sphinx warnings
- Documentation fix: Fix kernel-doc comment for __start_dirop() - the
function name in the comment was wrong and the @state parameter was
undocumented
- Replace dynamic folio_batch allocation with stack allocation in
iomap_zero_range(). The dynamic allocation was problematic for
ext4-on-iomap work (didn't handle allocation failure properly) and
triggered lockdep complaints. Uses a flag instead to control batch
usage
- Re-add #ifdef guards around PIDFD_GET_<ns-type>_NAMESPACE ioctls.
When a namespace type is disabled, ns->ops is NULL, causes crashes
during inode eviction when closing the fd. The ifdefs were removed in
a recent simplification but are still needed
- Fixe a race where a folio could be unlocked before the trailing zeros
(for EOF within the page) were written
- Split out a dedicated lease_dispose_list() helper since lease code
paths always know they're disposing of leases. Removes unnecessary
runtime flag checks and prepares for upcoming lease_manager
enhancements
- Fix userland delegation requests succeeding despite conflicting
opens. Previously, FL_LAYOUT and FL_DELEG leases bypassed conflict
checks (a hack for nfsd). Adds new ->lm_open_conflict() lease_manager
operation so userland delegations get proper conflict checking while
nfsd can continue its own conflict handling
- Fix LOOKUP_CACHED path lookups incorrectly falling through to the
slow path. After legitimize_links() calls were conditionally elided,
the routine would always fail with LOOKUP_CACHED regardless of
whether there were any links. Now the flag is checked at the two
callsites before calling legitimize_links()
- Fix bug in media fd allocation in media_request_alloc()
- Fix mismatched API calls in ecryptfs_mknod(): was calling
end_removing() instead of end_creating() after
ecryptfs_start_creating_dentry()
- Fix dentry reference count leak in ecryptfs_mkdir(): a dget() of the
lower parent dir was added but never dput()'d, causing BUG during
lower filesystem unmount due to the still-in-use dentry
* tag 'vfs-6.19-rc5.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
pidfs: protect PIDFD_GET_* ioctls() via ifdef
ecryptfs: Release lower parent dentry after creating dir
ecryptfs: Fix improper mknod pairing of start_creating()/end_removing()
get rid of bogus __user in struct xattr_args::value
VFS: fix __start_dirop() kernel-doc warnings
fs: Describe @isnew parameter in ilookup5_nowait()
fs: make sure to fail try_to_unlazy() and try_to_unlazy() for LOOKUP_CACHED
netfs: Fix early read unlock of page with EOF in middle
filelock: allow lease_managers to dictate what qualifies as a conflict
filelock: add lease_dispose_list() helper
iomap: replace folio_batch allocation with stack allocation
media: mc: fix potential use-after-free in media_request_alloc()
Anup Patel [Tue, 23 Dec 2025 14:35:44 +0000 (20:05 +0530)]
Revert "irqchip/riscv-imsic: Embed the vector array in lpriv"
The __alloc_percpu() fails when the number of IDs are greater than 959
because size parameter of __alloc_percpu() must be less than 32768 (aka
PCPU_MIN_UNIT_SIZE). This failure is observed with KVMTOOL when AIA is
trap-n-emulated by in-kernel KVM because in this case KVM guest has 2047
interrupt IDs.
To address this issue, don't embed vector array in struct imsic_local_priv
until __alloc_percpu() support size parameter greater than 32768.
This reverts commit 79eaabc61dfb ("irqchip/riscv-imsic: Embed the vector
array in lpriv").
Ming Lei [Fri, 9 Jan 2026 12:14:54 +0000 (20:14 +0800)]
ublk: fix use-after-free in ublk_partition_scan_work
A race condition exists between the async partition scan work and device
teardown that can lead to a use-after-free of ub->ub_disk:
1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk()
2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does:
- del_gendisk(ub->ub_disk)
- ublk_detach_disk() sets ub->ub_disk = NULL
- put_disk() which may free the disk
3. The worker ublk_partition_scan_work() then dereferences ub->ub_disk
leading to UAF
Fix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold
a reference to the disk during the partition scan. The spinlock in
ublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker
either gets a valid reference or sees NULL and exits early.
Also change flush_work() to cancel_work_sync() to avoid running the
partition scan work unnecessarily when the disk is already detached.
Fixes: 7fc4da6a304b ("ublk: scan partition in async way") Reported-by: Ruikai Peng <ruikai@pwno.io> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>