Linux kernel
============
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Pull xfs fixes from Carlos Maiolino:
"Just a single bug fix (and documentation for the issue)"
* tag 'xfs-fixes-6.18-rc4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: document another racy GC case in xfs_zoned_map_extent
xfs: prevent gc from picking the same zone twice
Pull Kbuild fixes from Nathan Chancellor:
- Formally adopt Kconfig in MAINTAINERS
- Fix install-extmod-build for more O= paths
- Align end of .modinfo to fix Authenticode calculation in EDK2
- Restore dynamic check for '-fsanitize=kernel-memory' in
CONFIG_HAVE_KMSAN_COMPILER to ensure backend target has support
for it
- Initialize locale in menuconfig and nconfig to fix UTF-8 terminals
that may not support VT100 ACS by default like PuTTY
* tag 'kbuild-fixes-6.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
kconfig/nconf: Initialize the default locale at startup
kconfig/mconf: Initialize the default locale at startup
KMSAN: Restore dynamic check for '-fsanitize=kernel-memory'
kbuild: align modinfo section for Secureboot Authenticode EDK2 compat
kbuild: install-extmod-build: Fix when given dir outside the build dir
MAINTAINERS: Update Kconfig section
Besides blocks being invalidated, there is another case when the original
mapping could have changed between querying the rmap for GC and calling
xfs_zoned_map_extent. Document it there as it took us quite some time
to figure out what is going on while developing the multiple-GC
protection fix.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Pull bpf fixes from Alexei Starovoitov:
- Mark migrate_disable/enable() as always_inline to avoid issues with
partial inlining (Yonghong Song)
- Fix powerpc stack register definition in libbpf bpf_tracing.h (Andrii
Nakryiko)
- Reject negative head_room in __bpf_skb_change_head (Daniel Borkmann)
- Conditionally include dynptr copy kfuncs (Malin Jonsson)
- Sync pending IRQ work before freeing BPF ring buffer (Noorain Eqbal)
- Do not audit capability check in x86 do_jit() (Ondrej Mosnacek)
- Fix arm64 JIT of BPF_ST insn when it writes into arena memory
(Puranjay Mohan)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf/arm64: Fix BPF_ST into arena memory
bpf: Make migrate_disable always inline to avoid partial inlining
bpf: Reject negative head_room in __bpf_skb_change_head
bpf: Conditionally include dynptr copy kfuncs
libbpf: Fix powerpc's stack register definition in bpf_tracing.h
bpf: Do not audit capability check in do_jit()
bpf: Sync pending IRQ work before freeing ring buffer
Fix bug where make nconfig doesn't initialize the default locale, which
causes ncurses menu borders to be displayed incorrectly (lqqqqk) in
UTF-8 terminals that don't support VT100 ACS by default, such as PuTTY.
Signed-off-by: Jakub Horký <jakub.git@horky.net>
Link: https://patch.msgid.link/20251014144405.3975275-2-jakub.git@horky.net
[nathan: Alphabetize locale.h include]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
When we are picking a zone for gc it might already be in the pipeline
which can lead to us moving the same data twice resulting in in write
amplification and a very unfortunate case where we keep on garbage
collecting the zone we just filled with migrated data stopping all
forward progress.
Fix this by introducing a count of on-going GC operations on a zone, and
skip any zone with ongoing GC when picking a new victim.
Fixes: 080d01c41 ("xfs: implement zoned garbage collection")
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Co-developed-by: Hans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Pull drm fixes from Simona Vetter:
"Looks like stochastics conspired to make this one a bit bigger, but
nothing scary at all. Also first examples of the new Link: tags, yay!
Next week Dave should be back.
Drivers:
- mediatek: uaf in unbind, fixes -rc2 boot regression
- radeon: devm conversion fixes
- amdgpu: VPE idle handler, re-enable DM idle optimization, DCN3,
SMU, vblank, HDP eDP, powerplay fixes for fiji/iceland
- msm: bunch of gem error path fixes, gmu fw parsing fix, dpu fixes
- intel: fix dmc/dc6 asserts on ADL-S
- xe: fix xe_validation_guard(), wake device handling around gt reset
- ast: fix display output on AST2300
- etnaviv: fix gpu flush
- imx: fix parallel bridge handling
- nouveau: scheduler locking fix
- panel: fixes for kingdisplay-kd097d04 and sitronix-st7789v
Core Changes:
- CI: disable broken sanity job
- sysfb: fix NULL pointer access
- sched: fix SIGKILL handling, locking for race condition
- dma_fence: better timeline name for signalled fences"
* tag 'drm-fixes-2025-10-31' of https://gitlab.freedesktop.org/drm/kernel: (44 commits)
drm/ast: Clear preserved bits from register output value
drm/imx: parallel-display: add the bridge before attaching it
drm/imx: parallel-display: convert to devm_drm_bridge_alloc() API
drm/panel: kingdisplay-kd097d04: Disable EoTp
drm/panel: sitronix-st7789v: fix sync flags for t28cp45tn89
drm/xe: Do not wake device during a GT reset
drm/xe: Fix uninitialized return value from xe_validation_guard()
drm/msm/dpu: Fix adjusted mode clock check for 3d merge
drm/msm/dpu: Disable broken YUV on QSEED2 hardware
drm/msm/dpu: Require linear modifier for writeback framebuffers
drm/msm/dpu: Fix pixel extension sub-sampling
drm/msm/dpu: Disable scaling for unsupported scaler types
drm/msm/dpu: Propagate error from dpu_assign_plane_resources
drm/msm/dpu: Fix allocation of RGB SSPPs without scaling
drm/msm: dsi: fix PLL init in bonded mode
drm/i915/dmc: Clear HRR EVT_CTL/HTP to zero on ADL-S
drm/amd/display: Fix incorrect return of vblank enable on unconfigured crtc
drm/amd/display: Add HDR workaround for a specific eDP
drm/amdgpu: fix SPDX header on cyan_skillfish_reg_init.c
drm/amdgpu: fix SPDX header on irqsrcs_vcn_5_0.h
...
The arm64 JIT supports BPF_ST with BPF_PROBE_MEM32 (arena) by using the
tmp2 register to hold the dst + arena_vm_base value and using tmp2 as the
new dst register. But this is broken because in case is_lsi_offset()
returns false the tmp2 will be clobbered by emit_a64_mov_i(1, tmp2, off,
ctx); and hence the emitted store instruction will be of the form:
strb w10, [x11, x11]
Fix this by using the third temporary register to hold the dst +
arena_vm_base.
Fixes: 339af577ec05 ("bpf: Add arm64 JIT support for PROBE_MEM32 pseudo instructions.")
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Link: https://lore.kernel.org/r/20251030121715.55214-1-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Fix bug where make menuconfig doesn't initialize the default locale, which
causes ncurses menu borders to be displayed incorrectly (lqqqqk) in
UTF-8 terminals that don't support VT100 ACS by default, such as PuTTY.
Signed-off-by: Jakub Horký <jakub.git@horky.net>
Link: https://patch.msgid.link/20251014154933.3990990-1-jakub.git@horky.net
[nathan: Alphabetize locale.h include]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
On a filesystem with parent pointers, xchk_nlinks_collect_dir walks both
the directory entries (data fork) and the parent pointers (attr fork) to
determine the correct link count. Unfortunately I forgot to update the
lock mode logic to handle the case of a directory whose attr fork is in
btree format and has not yet been loaded *and* whose data fork doesn't
need loading.
This leads to a bunch of assertions from xfs/286 in xfs_iread_extents
because we only took ILOCK_SHARED, not ILOCK_EXCL. You'd need the rare
happenstance of a directory with a large number of non-pptr extended
attributes set and enough memory pressure to cause the directory to be
evicted and partially reloaded from disk.
I /think/ this only started in 6.18-rc1 because I've started seeing OOM
errors with the maple tree slab using 70% of memory, and this didn't
happen in 6.17. Yay dynamic systems!
Cc: stable@vger.kernel.org # v6.10
Fixes: 77ede5f44b0d86 ("xfs: walk directory parent pointers to determine backref count")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Pull pci fixes from Bjorn Helgaas:
- Restore custom qcom ASPM enablement code so L1 PM Substates are
enabled as they were in v6.17 even though the PCI core now enables
just L0s and L1 by default (Bjorn Helgaas)
- Size prefetchable bridge windows only when they actually exist, to
avoid a WARN_ON() regression (Ilpo Järvinen)
* tag 'pci-v6.18-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
PCI: Do not size non-existing prefetchable window
Revert "PCI: qcom: Remove custom ASPM enablement code"
Driver Changes:
- Fix xe_validation_guard() not guarding (Thomas Hellström)
- Do not wake device during a GT reset (Matthew Brost)
Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch>
From: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patch.msgid.link/o2b3lucyitafbbcd5bewpfqnslavtnnpc6ck4qatnou2wwukix@rz6seyfw75uy
The build fails with llvm 21/22:
$ make LLVM=1 -j
...
LD vmlinux.o
GEN .vmlinux.objs
...
BTF .tmp_vmlinux1.btf.o
...
AS .tmp_vmlinux2.kallsyms.o
LD vmlinux.unstripped
BTFIDS vmlinux.unstripped
WARN: resolve_btfids: unresolved symbol migrate_enable
WARN: resolve_btfids: unresolved symbol migrate_disable
make[2]: *** [vmlinux.unstripped] Error 255
make[2]: *** Deleting file 'vmlinux.unstripped'
make[1]: *** [Makefile:1242: vmlinux] Error 2
make: *** [Makefile:248: __sub-make] Error 2
Two functions with identical names but different addresses are
considered ambiguous and removed by "pahole" from vmlinux BTF.
Later resolve_btfids warns since it cannot find them.
Commit 378b7708194f ("sched: Make migrate_{en,dis}able() inline") made
them inlineable in most places, but in vmlinux built with llvm 21 and 22
there are four symbols for migrate_{enable,disable}:
three static functions and one global function.
Fix the issue by marking migrate_{enable,disable} as always inline.
The alternative is to mark them as notrace/nokprobe which is more
drastic. Only bpf programs are prevented from attaching to these
functions. The rest of the tracing shouldn't be affected.
[note: Peter ok-ed the patch, Alexei rewrote commit log]
Fixes: 378b7708194f ("sched: Make migrate_{en,dis}able() inline")
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Menglong Dong <menglong.dong@linux.dev>
Link: https://lore.kernel.org/r/20251029183646.3811774-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit 5ff8c11775c7 ("KMSAN: Remove tautological checks") changed
CONFIG_HAVE_KMSAN_COMPILER from a dynamic check for
'-fsanitize=kernel-memory' to just being true for CONFIG_CC_IS_CLANG.
This missed the fact that not all architectures supported
'-fsanitize=kernel-memory' at the same time. For example, SystemZ / s390
gained support for KMSAN in clang-18 [1], so builds with clang-15
through clang-17 can select KMSAN but they error with:
clang-16: error: unsupported option '-fsanitize=kernel-memory' for target 's390x-unknown-linux-gnu'
Restore the cc-option check for '-fsanitize=kernel-memory' to make sure
the compiler target properly supports '-fsanitize=kernel-memory'. The
check for '-msan-disable-checks=1' does not need to be restored because
all supported clang versions for building the kernel support it.
Fixes: 5ff8c11775c7 ("KMSAN: Remove tautological checks")
Link: https://github.com/llvm/llvm-project/commit/a3e56a8792ffaf3a3d3538736e1042b8db45ab89 [1]
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/r/202510220236.AVuXXCYy-lkp@intel.com/
Acked-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/20251023-fix-kmsan-check-s390-clang-v1-1-4e6df477a4cc@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Apparently we can never deprecate mount options in this project, because
it will invariably turn out that some foolish userspace depends on some
behavior and break. From Oleksandr Natalenko:
In v6.18, the attr2 XFS mount option is removed. This may silently
break system boot if the attr2 option is still present in /etc/fstab
for rootfs.
Consider Arch Linux that is being set up from scratch with / being
formatted as XFS. The genfstab command that is used to generate
/etc/fstab produces something like this by default:
/dev/sda2 on / type xfs (rw,relatime,attr2,discard,inode64,logbufs=8,logbsize=32k,noquota)
Once the system is set up and rebooted, there's no deprecation warning
seen in the kernel log:
# cat /proc/cmdline
root=UUID=77b42de2-397e-47ee-a1ef-4dfd430e47e9 rootflags=discard rd.luks.options=discard quiet
# dmesg | grep -i xfs
[ 2.409818] SGI XFS with ACLs, security attributes, realtime, scrub, repair, quota, no debug enabled
[ 2.415341] XFS (sda2): Mounting V5 Filesystem 77b42de2-397e-47ee-a1ef-4dfd430e47e9
[ 2.442546] XFS (sda2): Ending clean mount
Although as per the deprecation intention, it should be there.
Vlastimil (in Cc) suggests this is because xfs_fs_warn_deprecated()
doesn't produce any warning by design if the XFS FS is set to be
rootfs and gets remounted read-write during boot. This imposes two
problems:
1) a user doesn't see the deprecation warning; and
2) with v6.18 kernel, the read-write remount fails because of unknown
attr2 option rendering system unusable:
systemd[1]: Switching root.
systemd-remount-fs[225]: /usr/bin/mount for / exited with exit status 32.
# mount -o rw /
mount: /: fsconfig() failed: xfs: Unknown parameter 'attr2'.
Thorsten (in Cc) suggested reporting this as a user-visible regression.
From my PoV, although the deprecation is in place for 5 years already,
it may not be visible enough as the warning is not emitted for rootfs.
Considering the amount of systems set up with XFS on /, this may
impose a mass problem for users.
Vlastimil suggested making attr2 option a complete noop instead of
removing it.
IOWs, the initrd mounts the root fs with (I assume) no mount options,
and mount -a remounts with whatever options are in fstab. However,
XFS doesn't complain about deprecated mount options during a remount, so
technically speaking we were not warning all users in all combinations
that they were heading for a cliff.
Gotcha!!
Now, how did 'attr2' get slurped up on so many systems? The old code
would put that in /proc/mounts if the filesystem happened to be in attr2
mode, even if user hadn't mounted with any such option. IOWs, this is
because someone thought it would be a good idea to advertise system
state via /proc/mounts.
The easy way to fix this is to reintroduce the four mount options but
map them to a no-op option that ignores them, and hope that nobody's
depending on attr2 to appear in /proc/mounts. (Hint: use the fsgeometry
ioctl). But we've learned our lesson, so complain as LOUDLY as possible
about the deprecation.
Lessons learned:
1. Don't expose system state via /proc/mounts; the only strings that
ought to be there are options *explicitly* provided by the user.
2. Never tidy, it's not worth the stress and irritation.
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: stable@vger.kernel.org # v6.18-rc1
Fixes: b9a176e54162f8 ("xfs: remove deprecated mount options")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Pull VFIO fixes from Alex Williamson:
- Fix overflows in vfio type1 backend for mappings at the end of the
64-bit address space, resulting in leaked pinned memory.
New selftest support included to avoid such issues in the future
(Alex Mastro)
* tag 'vfio-v6.18-rc4' of https://github.com/awilliam/linux-vfio:
vfio: selftests: add end of address space DMA map/unmap tests
vfio: selftests: update DMA map/unmap helpers to support more test kinds
vfio/type1: handle DMA map/unmap up to the addressable limit
vfio/type1: move iova increment to unmap_unpin_*() caller
vfio/type1: sanitize for overflow using check_*_overflow()