string:
- add mem_is_zero()
core:
- support more device numbers
- use XArray for minor ids
- add backlight constants
- Split dma fence array creation into alloc and arm
fbdev:
- remove usage of old fbdev hooks
kms:
- Add might_fault() to drm_modeset_lock priming
- Add dynamic per-crtc vblank configuration support
dma-buf:
- docs cleanup
buddy:
- Add start address support for trim function
printk:
- pass description to kmsg_dump
scheduler;
- Remove full_recover from drm_sched_start
ttm:
- Make LRU walk restartable after dropping locks
- Allow direct reclaim to allocate local memory
panic:
- add display QR code (in rust)
displayport:
- mst: GUID improvements
bridge:
- Silence error message on -EPROBE_DEFER
- analogix: Clean aup
- bridge-connector: Fix double free
- lt6505: Disable interrupt when powered off
- tc358767: Make default DP port preemphasis configurable
- lt9611uxc: require DRM_BRIDGE_ATTACH_NO_CONNECTOR
- anx7625: simplify OF array handling
- dw-hdmi: simplify clock handling
- lontium-lt8912b: fix mode validation
- nwl-dsi: fix mode vsync/hsync polarity
xe:
- Enable LunarLake and Battlemage support
- Introducing Xe2 ccs modifiers for integrated and discrete graphics
- rename xe perf to xe observation
- use wb caching on DGFX for system memory
- add fence timeouts
- Lunar Lake graphics/media/display workarounds
- Battlemage workarounds
- Battlemage GSC support
- GSC and HuC fw updates for LL/BM
- use dma_fence_chain_free
- refactor hw engine lookup and mmio access
- enable priority mem read for Xe2
- Add first GuC BMG fw
- fix dma-resv lock
- Fix DGFX display suspend/resume
- Use xe_managed for kernel BOs
- Use reserved copy engine for user binds on faulting devices
- Allow mixing dma-fence jobs and long-running faulting jobs
- fix media TLB invalidation
- fix rpm in TTM swapout path
- track resources and VF state by PF
i915:
- Type-C programming fix for MTL+
- FBC cleanup
- Calc vblank delay more accurately
- On DP MST, Enable LT fallback for UHBR<->non-UHBR rates
- Fix DP LTTPR detection
- limit relocations to INT_MAX
- fix long hangs in buddy allocator on DG2/A380
amdgpu:
- Per-queue reset support
- SDMA devcoredump support
- DCN 4.0.1 updates
- GFX12/VCN4/JPEG4 updates
- Convert vbios embedded EDID to drm_edid
- GFX9.3/9.4 devcoredump support
- process isolation framework for GFX 9.4.3/4
- take IOMMU mappings into account for P2P DMA
amdkfd:
- CRIU fixes
- HMM fix
- Enable process isolation support for GFX 9.4.3/4
- Allow users to target recommended SDMA engines
- KFD support for targetting queues on recommended SDMA engines
radeon:
- remove .load and drm_dev_alloc
- Fix vbios embedded EDID size handling
- Convert vbios embedded EDID to drm_edid
- Use GEM references instead of TTM
- r100 cp init cleanup
- Fix potential overflows in evergreen CS offset tracking
msm:
- DPU:
- implement DP/PHY mapping on SC8180X
- Enable writeback on SM8150, SC8180X, SM6125, SM6350
- DP:
- Enable widebus on all relevant chipsets
- MSM8998 HDMI support
- GPU:
- A642L speedbin support
- A615/A306/A621 support
- A7xx devcoredump support
ast:
- astdp: Support AST2600 with VGA
- Clean up HPD
- Fix timeout loop for DP link training
- reorganize output code by type (VGA, DP, etc)
- convert to struct drm_edid
- fix BMC handling for all outputs
exynos:
- drop stale MAINTAINERS pattern
- constify struct
loongson:
- use GEM refcount over TTM
mgag200:
- Improve BMC handling
- Support VBLANK intterupts
- transparently support BMC outputs
nouveau:
- Refactor and clean up internals
- Use GEM refcount over TTM's
gm12u320:
- convert to struct drm_edid
gma500:
- update i2c terms
lcdif:
- pixel clock fix
host1x:
- fix syncpoint IRQ during resume
- use iommu_paging_domain_alloc()
imx:
- ipuv3: convert to struct drm_edid
omapdrm:
- improve error handling
- use common helper for_each_endpoint_of_node()
panel:
- add support for BOE TV101WUM-LL2 plus DT bindings
- novatek-nt35950: improve error handling
- nv3051d: improve error handling
- panel-edp: add support for BOE NE140WUM-N6G; revert support for
SDC ATNA45AF01
- visionox-vtdr6130: improve error handling; use
devm_regulator_bulk_get_const()
- boe-th101mb31ig002: Support for starry-er88577 MIPI-DSI panel plus
DT; Fix porch parameter
- edp: Support AOU B116XTN02.3, AUO B116XAN06.1, AOU B116XAT04.1,
BOE NV140WUM-N41, BOE NV133WUM-N63, BOE NV116WHM-A4D, CMN N116BCA-EA2,
CMN N116BCP-EA2, CSW MNB601LS1-4
- himax-hx8394: Support Microchip AC40T08A MIPI Display panel plus DT
- ilitek-ili9806e: Support Densitron DMT028VGHMCMI-1D TFT plus DT
- jd9365da: Support Melfas lmfbx101117480 MIPI-DSI panel plus DT; Refactor
for code sharing
- panel-edp: fix name for HKC MB116AN01
- jd9365da: fix "exit sleep" commands
- jdi-fhd-r63452: simplify error handling with DSI multi-style
helpers
- mantix-mlaf057we51: simplify error handling with DSI multi-style
helpers
- simple:
support Innolux G070ACE-LH3 plus DT bindings
support On Tat Industrial Company KD50G21-40NT-A1 plus DT bindings
- st7701:
decouple DSI and DRM code
add SPI support
support Anbernic RG28XX plus DT bindings
mediatek:
- support alpha blending
- remove cl in struct cmdq_pkt
- ovl adaptor fix
- add power domain binding for mediatek DPI controller
renesas:
- rz-du: add support for RZ/G2UL plus DT bindings
rockchip:
- Improve DP sink-capability reporting
- dw_hdmi: Support 4k@60Hz
- vop: Support RGB display on Rockchip RK3066; Support 4096px width
sti:
- convert to struct drm_edid
stm:
- Avoid UAF wih managed plane and CRTC helpers
- Fix module owner
- Fix error handling in probe
- Depend on COMMON_CLK
- ltdc: Fix transparency after disabling plane; Remove unused interrupt
tegra:
- gr3d: improve PM domain handling
- convert to struct drm_edid
- Call drm_atomic_helper_shutdown()
vc4:
- fix PM during detect
- replace DRM_ERROR() with drm_error()
- v3d: simplify clock retrieval
v3d:
- Clean up perfmon
virtio:
- add DRM capset
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Merge tag 'drm-next-2024-09-19' of https://gitlab.freedesktop.org/drm/kernel
Pull drm updates from Dave Airlie:
"This adds a couple of patches outside the drm core, all should be
acked appropriately, the string and pstore ones are the main ones that
come to mind.
Otherwise it's the usual drivers, xe is getting enabled by default on
some new hardware, we've changed the device number handling to allow
more devices, and we added some optional rust code to create QR codes
in the panic handler, an idea first suggested I think 10 years ago :-)
string:
- add mem_is_zero()
core:
- support more device numbers
- use XArray for minor ids
- add backlight constants
- Split dma fence array creation into alloc and arm
fbdev:
- remove usage of old fbdev hooks
kms:
- Add might_fault() to drm_modeset_lock priming
- Add dynamic per-crtc vblank configuration support
dma-buf:
- docs cleanup
buddy:
- Add start address support for trim function
printk:
- pass description to kmsg_dump
scheduler:
- Remove full_recover from drm_sched_start
ttm:
- Make LRU walk restartable after dropping locks
- Allow direct reclaim to allocate local memory
panic:
- add display QR code (in rust)
displayport:
- mst: GUID improvements
bridge:
- Silence error message on -EPROBE_DEFER
- analogix: Clean aup
- bridge-connector: Fix double free
- lt6505: Disable interrupt when powered off
- tc358767: Make default DP port preemphasis configurable
- lt9611uxc: require DRM_BRIDGE_ATTACH_NO_CONNECTOR
- anx7625: simplify OF array handling
- dw-hdmi: simplify clock handling
- lontium-lt8912b: fix mode validation
- nwl-dsi: fix mode vsync/hsync polarity
xe:
- Enable LunarLake and Battlemage support
- Introducing Xe2 ccs modifiers for integrated and discrete graphics
- rename xe perf to xe observation
- use wb caching on DGFX for system memory
- add fence timeouts
- Lunar Lake graphics/media/display workarounds
- Battlemage workarounds
- Battlemage GSC support
- GSC and HuC fw updates for LL/BM
- use dma_fence_chain_free
- refactor hw engine lookup and mmio access
- enable priority mem read for Xe2
- Add first GuC BMG fw
- fix dma-resv lock
- Fix DGFX display suspend/resume
- Use xe_managed for kernel BOs
- Use reserved copy engine for user binds on faulting devices
- Allow mixing dma-fence jobs and long-running faulting jobs
- fix media TLB invalidation
- fix rpm in TTM swapout path
- track resources and VF state by PF
i915:
- Type-C programming fix for MTL+
- FBC cleanup
- Calc vblank delay more accurately
- On DP MST, Enable LT fallback for UHBR<->non-UHBR rates
- Fix DP LTTPR detection
- limit relocations to INT_MAX
- fix long hangs in buddy allocator on DG2/A380
amdgpu:
- Per-queue reset support
- SDMA devcoredump support
- DCN 4.0.1 updates
- GFX12/VCN4/JPEG4 updates
- Convert vbios embedded EDID to drm_edid
- GFX9.3/9.4 devcoredump support
- process isolation framework for GFX 9.4.3/4
- take IOMMU mappings into account for P2P DMA
amdkfd:
- CRIU fixes
- HMM fix
- Enable process isolation support for GFX 9.4.3/4
- Allow users to target recommended SDMA engines
- KFD support for targetting queues on recommended SDMA engines
radeon:
- remove .load and drm_dev_alloc
- Fix vbios embedded EDID size handling
- Convert vbios embedded EDID to drm_edid
- Use GEM references instead of TTM
- r100 cp init cleanup
- Fix potential overflows in evergreen CS offset tracking
msm:
- DPU:
- implement DP/PHY mapping on SC8180X
- Enable writeback on SM8150, SC8180X, SM6125, SM6350
- DP:
- Enable widebus on all relevant chipsets
- MSM8998 HDMI support
- GPU:
- A642L speedbin support
- A615/A306/A621 support
- A7xx devcoredump support
ast:
- astdp: Support AST2600 with VGA
- Clean up HPD
- Fix timeout loop for DP link training
- reorganize output code by type (VGA, DP, etc)
- convert to struct drm_edid
- fix BMC handling for all outputs
exynos:
- drop stale MAINTAINERS pattern
- constify struct
loongson:
- use GEM refcount over TTM
mgag200:
- Improve BMC handling
- Support VBLANK intterupts
- transparently support BMC outputs
nouveau:
- Refactor and clean up internals
- Use GEM refcount over TTM's
gm12u320:
- convert to struct drm_edid
gma500:
- update i2c terms
lcdif:
- pixel clock fix
host1x:
- fix syncpoint IRQ during resume
- use iommu_paging_domain_alloc()
imx:
- ipuv3: convert to struct drm_edid
omapdrm:
- improve error handling
- use common helper for_each_endpoint_of_node()
panel:
- add support for BOE TV101WUM-LL2 plus DT bindings
- novatek-nt35950: improve error handling
- nv3051d: improve error handling
- panel-edp:
- add support for BOE NE140WUM-N6G
- revert support for SDC ATNA45AF01
- visionox-vtdr6130:
- improve error handling
- use devm_regulator_bulk_get_const()
- boe-th101mb31ig002:
- Support for starry-er88577 MIPI-DSI panel plus DT
- Fix porch parameter
- edp: Support AOU B116XTN02.3, AUO B116XAN06.1, AOU B116XAT04.1, BOE
NV140WUM-N41, BOE NV133WUM-N63, BOE NV116WHM-A4D, CMN N116BCA-EA2,
CMN N116BCP-EA2, CSW MNB601LS1-4
- himax-hx8394: Support Microchip AC40T08A MIPI Display panel plus DT
- ilitek-ili9806e: Support Densitron DMT028VGHMCMI-1D TFT plus DT
- jd9365da:
- Support Melfas lmfbx101117480 MIPI-DSI panel plus DT
- Refactor for code sharing
- panel-edp: fix name for HKC MB116AN01
- jd9365da: fix "exit sleep" commands
- jdi-fhd-r63452: simplify error handling with DSI multi-style
helpers
- mantix-mlaf057we51: simplify error handling with DSI multi-style
helpers
- simple:
- support Innolux G070ACE-LH3 plus DT bindings
- support On Tat Industrial Company KD50G21-40NT-A1 plus DT
bindings
- st7701:
- decouple DSI and DRM code
- add SPI support
- support Anbernic RG28XX plus DT bindings
mediatek:
- support alpha blending
- remove cl in struct cmdq_pkt
- ovl adaptor fix
- add power domain binding for mediatek DPI controller
renesas:
- rz-du: add support for RZ/G2UL plus DT bindings
rockchip:
- Improve DP sink-capability reporting
- dw_hdmi: Support 4k@60Hz
- vop:
- Support RGB display on Rockchip RK3066
- Support 4096px width
sti:
- convert to struct drm_edid
stm:
- Avoid UAF wih managed plane and CRTC helpers
- Fix module owner
- Fix error handling in probe
- Depend on COMMON_CLK
- ltdc:
- Fix transparency after disabling plane
- Remove unused interrupt
tegra:
- gr3d: improve PM domain handling
- convert to struct drm_edid
- Call drm_atomic_helper_shutdown()
vc4:
- fix PM during detect
- replace DRM_ERROR() with drm_error()
- v3d: simplify clock retrieval
v3d:
- Clean up perfmon
virtio:
- add DRM capset"
* tag 'drm-next-2024-09-19' of https://gitlab.freedesktop.org/drm/kernel: (1326 commits)
drm/xe: Fix missing conversion to xe_display_pm_runtime_resume
drm/xe/xe2hpg: Add Wa_15016589081
drm/xe: Don't keep stale pointer to bo->ggtt_node
drm/xe: fix missing 'xe_vm_put'
drm/xe: fix build warning with CONFIG_PM=n
drm/xe: Suppress missing outer rpm protection warning
drm/xe: prevent potential UAF in pf_provision_vf_ggtt()
drm/amd/display: Add all planes on CRTC to state for overlay cursor
drm/i915/bios: fix printk format width
drm/i915/display: Fix BMG CCS modifiers
drm/amdgpu: get rid of bogus includes of fdtable.h
drm/amdkfd: CRIU fixes
drm/amdgpu: fix a race in kfd_mem_export_dmabuf()
drm: new helper: drm_gem_prime_handle_to_dmabuf()
drm/amdgpu/atomfirmware: Silence UBSAN warning
drm/amdgpu: Fix kdoc entry in 'amdgpu_vm_cpu_prepare'
drm/amd/amdgpu: apply command submission parser for JPEG v1
drm/amd/amdgpu: apply command submission parser for JPEG v2+
drm/amd/pm: fix the pp_dpm_pcie issue on smu v14.0.2/3
drm/amd/pm: update the features set on smu v14.0.2/3
...
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Merge v6.11-rc5 into drm-next
amdgpu pr conconflicts due to patches cherry-picked to -fixes, I might
as well catch up with a backmerge and handle them all. Plus both misc
and intel maintainers asked for a backmerge anyway.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Mark an emergency section beginning with oops_enter() until the
end of oops_exit(). In this section, every printk() call will
attempt to directly flush to the consoles using the EMERGENCY
priority.
The very end of oops_exit() performs a kmsg_dump(). This is not
included in the emergency section because it is another
flushing mechanism that should occur after the consoles have
flushed the oops messages.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240820063001.36405-34-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Mark the full contents of __warn() as an emergency section. In
this section, every printk() call will attempt to directly
flush to the consoles using the EMERGENCY priority.
Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240820063001.36405-33-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
If legacy and nbcon consoles are registered and the nbcon
consoles are allowed to flush (i.e. no boot consoles
registered), the legacy consoles will no longer perform
direct printing on the panic CPU until after the backtrace
has been stored. This will give the safe nbcon consoles a
chance to print the panic messages before allowing the
unsafe legacy consoles to print.
If no nbcon consoles are registered or they are not allowed
to flush because boot consoles are registered, there is no
change in behavior (i.e. legacy consoles will always attempt
to print from the printk() caller context).
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240820063001.36405-30-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Add nbcon_atomic_flush_unsafe() to flush all nbcon consoles
using the write_atomic() callback and allowing unsafe hostile
takeovers. Call this at the end of panic() as a final attempt
to flush any pending messages.
Note that legacy consoles use unsafe methods for flushing
from the beginning of panic (see bust_spinlocks()). Therefore,
systems using both legacy and nbcon consoles may still fail to
see panic messages due to unsafe legacy console usage.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240820063001.36405-27-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
commit 779dbc2e78 ("printk: Avoid non-panic CPUs writing
to ringbuffer") disabled non-panic CPUs to further write messages to
ringbuffer after panicked.
Since the commit, non-panicked CPU's are not allowed to write to
ring buffer after panicked and CPU backtrace which is triggered
after panicked to sample non-panicked CPUs' backtrace no longer
serves its function as it has nothing to print.
Fix the issue by allowing non-panicked CPUs to write into ringbuffer
while CPU backtrace is in flight.
Fixes: 779dbc2e78 ("printk: Avoid non-panic CPUs writing to ringbuffer")
Signed-off-by: Ryo Takakura <takakura@valinux.co.jp>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240812072703.339690-1-takakura@valinux.co.jp
Signed-off-by: Petr Mladek <pmladek@suse.com>
kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
callback.
This patch adds a new struct kmsg_dump_detail, that will hold the
reason and description, and pass it to the dump() callback.
To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
function and a macro for backward compatibility.
I've written this for drm_panic, but it can be useful for other
kmsg_dumper.
It allows to see the panic reason, like "sysrq triggered crash"
or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
v2:
* Use a struct kmsg_dump_detail to hold the reason and description
pointer, for more flexibility if we want to add other parameters.
(Kees Cook)
* Fix powerpc/nvram_64 build, as I didn't update the forward
declaration of oops_to_nvram()
Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Kees Cook <kees@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240702122639.248110-1-jfalempe@redhat.com
With nearly 20 taint flags and respective characters, it's getting a bit
difficult to remember what each taint flag character means. Add verbose
logging of the set taints in the format:
Tainted: [P]=PROPRIETARY_MODULE, [W]=WARN
in dump_stack_print_info() when there are taints.
Note that the "negative flag" G is not included.
Link: https://lkml.kernel.org/r/7321e306166cb2ca2807ab8639e665baa2462e9c.1717146197.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Convert print_tainted() to use struct seq_buf internally in order to be
more aware of the buffer constraints as well as make it easier to extend
in follow-up work.
Link: https://lkml.kernel.org/r/cb6006fa7c0f82a6b6885e8eea2920fcdc4fc9d0.1717146197.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)
Remove the sentinel from ctl_table arrays. Reduce by one the values used
to compare the size of the adjusted arrays.
Signed-off-by: Joel Granados <j.granados@samsung.com>
heap optimizations".
- Kuan-Wei Chiu has also sped up the library sorting code in the series
"lib/sort: Optimize the number of swaps and comparisons".
- Alexey Gladkov has added the ability for code running within an IPC
namespace to alter its IPC and MQ limits. The series is "Allow to
change ipc/mq sysctls inside ipc namespace".
- Geert Uytterhoeven has contributed some dhrystone maintenance work in
the series "lib: dhry: miscellaneous cleanups".
- Ryusuke Konishi continues nilfs2 maintenance work in the series
"nilfs2: eliminate kmap and kmap_atomic calls"
"nilfs2: fix kernel bug at submit_bh_wbc()"
- Nathan Chancellor has updated our build tools requirements in the
series "Bump the minimum supported version of LLVM to 13.0.1".
- Muhammad Usama Anjum continues with the selftests maintenance work in
the series "selftests/mm: Improve run_vmtests.sh".
- Oleg Nesterov has done some maintenance work against the signal code
in the series "get_signal: minor cleanups and fix".
Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.
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Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
- Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
heap optimizations".
- Kuan-Wei Chiu has also sped up the library sorting code in the series
"lib/sort: Optimize the number of swaps and comparisons".
- Alexey Gladkov has added the ability for code running within an IPC
namespace to alter its IPC and MQ limits. The series is "Allow to
change ipc/mq sysctls inside ipc namespace".
- Geert Uytterhoeven has contributed some dhrystone maintenance work in
the series "lib: dhry: miscellaneous cleanups".
- Ryusuke Konishi continues nilfs2 maintenance work in the series
"nilfs2: eliminate kmap and kmap_atomic calls"
"nilfs2: fix kernel bug at submit_bh_wbc()"
- Nathan Chancellor has updated our build tools requirements in the
series "Bump the minimum supported version of LLVM to 13.0.1".
- Muhammad Usama Anjum continues with the selftests maintenance work in
the series "selftests/mm: Improve run_vmtests.sh".
- Oleg Nesterov has done some maintenance work against the signal code
in the series "get_signal: minor cleanups and fix".
Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.
* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
nilfs2: prevent kernel bug at submit_bh_wbc()
nilfs2: fix failure to detect DAT corruption in btree and direct mappings
ocfs2: enable ocfs2_listxattr for special files
ocfs2: remove SLAB_MEM_SPREAD flag usage
assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
buildid: use kmap_local_page()
watchdog/core: remove sysctl handlers from public header
nilfs2: use div64_ul() instead of do_div()
mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
kexec: copy only happens before uchunk goes to zero
get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
get_signal: don't abuse ksig->info.si_signo and ksig->sig
const_structs.checkpatch: add device_type
Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>"
dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
list: leverage list_is_head() for list_entry_is_head()
nilfs2: MAINTAINERS: drop unreachable project mirror site
smp: make __smp_processor_id() 0-argument macro
fat: fix uninitialized field in nostale filehandles
...
For debugging kernel panics and other bugs, there is already an option of
panic_print to dump all tasks' call stacks. On today's large servers
running many containers, there could be thousands of tasks or more, and
this will print out huge amount of call stacks, taking a lot of time (for
serial console which is main target user case of panic_print).
And in many cases, only those several tasks being blocked are key for the
panic, so add an option to only dump blocked tasks' call stacks.
[akpm@linux-foundation.org: clarify documentation a little]
Link: https://lkml.kernel.org/r/20240202132042.3609657-1-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
with GCC 13.2.1 and W=1, there's compiling warning like this:
kernel/panic.c: In function `__warn':
kernel/panic.c:676:17: warning: function `__warn' might be a candidate for `gnu_printf' format attribute [-Wsuggest-attribute=format]
676 | vprintk(args->fmt, args->args);
| ^~~~~~~
The normal __printf(x,y) adding can't fix it. So add workaround which
disables -Wsuggest-attribute=format to mute it.
Link: https://lkml.kernel.org/r/20240107091641.579849-1-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If the kernel crashes in a context where printk() calls always
defer printing (such as in NMI or inside a printk_safe section)
then the final panic messages will be deferred to irq_work. But
if irq_work is not available, the messages will not get printed
unless explicitly flushed. The result is that the final
"end Kernel panic" banner does not get printed.
Add one final flush after the last printk() call to make sure
the final panic messages make it out as well.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240207134103.1357162-14-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Use atomic_try_cmpxchg instead of atomic_cmpxchg (*ptr, old, new) == old
in panic() and nmi_panic(). x86 CMPXCHG instruction returns success in ZF
flag, so this change saves a compare after cmpxchg (and related move
instruction in front of cmpxchg).
Also, rename cpu variable to this_cpu in nmi_panic() and try to unify
logic flow between panic() and nmi_panic().
No functional change intended.
[ubizjak@gmail.com: clean up if/else block]
Link: https://lkml.kernel.org/r/20230906191200.68707-1-ubizjak@gmail.com
Link: https://lkml.kernel.org/r/20230904152230.9227-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit:
5a5d7e9bad ("cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG")
amended warn_slowpath_fmt() to disable preemption until the WARN splat
has been emitted.
However the commit neglected to reenable preemption in the !fmt codepath,
i.e. when a WARN splat is emitted without additional format string.
One consequence is that users may see more splats than intended. E.g. a
WARN splat emitted in a work item results in at least two extra splats:
BUG: workqueue leaked lock or atomic
(emitted by process_one_work())
BUG: scheduling while atomic
(emitted by worker_thread() -> schedule())
Ironically the point of the commit was to *avoid* extra splats. ;)
Fix it.
Fixes: 5a5d7e9bad ("cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/3ec48fde01e4ee6505f77908ba351bad200ae3d1.1694763684.git.lukas@wunner.de
All callers of show_mem() pass 0 and NULL, so we can remove the two
arguments by directly calling __show_mem(0, NULL, MAX_NR_ZONES - 1) in
show_mem().
Link: https://lkml.kernel.org/r/20230630062253.189440-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Building with W=1 shows warnings about two functions that have no
declaration or caller in certain configurations:
kernel/panic.c:688:6: error: no previous prototype for 'warn_slowpath_fmt' [-Werror=missing-prototypes]
kernel/panic.c:710:6: error: no previous prototype for '__warn_printk' [-Werror=missing-prototypes]
Enclose the definition in the same #ifdef check as the declaration.
Link: https://lkml.kernel.org/r/20230517131102.934196-8-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit 8d470a45d1 ("panic: add option to dump all CPUs backtraces in
panic_print") introduced a setting for the "panic_print" kernel parameter
to allow users to request a NMI backtrace on panic. Problem is that the
panic_print handling happens after the secondary CPUs are already
disabled, hence this option ended-up being kind of a no-op - kernel skips
the NMI trace in idling CPUs, which is the case of offline CPUs.
Fix it by checking the NMI backtrace bit in the panic_print prior to the
CPU disabling function.
Link: https://lkml.kernel.org/r/20230226160838.414257-1-gpiccoli@igalia.com
Fixes: 8d470a45d1 ("panic: add option to dump all CPUs backtraces in panic_print")
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Cc: <stable@vger.kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In order to avoid WARN/BUG from generating nested or even recursive
warnings, force rcu_is_watching() true during
WARN/lockdep_rcu_suspicious().
Notably things like unwinding the stack can trigger rcu_dereference()
warnings, which then triggers more unwinding which then triggers more
warnings etc..
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230126151323.408156109@infradead.org
Use a temporary variable to take full advantage of READ_ONCE() behavior.
Without this, the report (and even the test) might be out of sync with
the initial test.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/lkml/Y5x7GXeluFmZ8E0E@hirez.programming.kicks-ass.net
Fixes: 9fc9e278a5 ("panic: Introduce warn_limit")
Fixes: d4ccd54d28 ("exit: Put an upper limit on how often we can oops")
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jann Horn <jannh@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Kees Cook <keescook@chromium.org>
- Convert flexible array members, fix -Wstringop-overflow warnings,
and fix KCFI function type mismatches that went ignored by
maintainers (Gustavo A. R. Silva, Nathan Chancellor, Kees Cook).
- Remove the remaining side-effect users of ksize() by converting
dma-buf, btrfs, and coredump to using kmalloc_size_roundup(),
add more __alloc_size attributes, and introduce full testing
of all allocator functions. Finally remove the ksize() side-effect
so that each allocation-aware checker can finally behave without
exceptions.
- Introduce oops_limit (default 10,000) and warn_limit (default off)
to provide greater granularity of control for panic_on_oops and
panic_on_warn (Jann Horn, Kees Cook).
- Introduce overflows_type() and castable_to_type() helpers for
cleaner overflow checking.
- Improve code generation for strscpy() and update str*() kern-doc.
- Convert strscpy and sigphash tests to KUnit, and expand memcpy
tests.
- Always use a non-NULL argument for prepare_kernel_cred().
- Disable structleak plugin in FORTIFY KUnit test (Anders Roxell).
- Adjust orphan linker section checking to respect CONFIG_WERROR
(Xin Li).
- Make sure siginfo is cleared for forced SIGKILL (haifeng.xu).
- Fix um vs FORTIFY warnings for always-NULL arguments.
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Merge tag 'hardening-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull kernel hardening updates from Kees Cook:
- Convert flexible array members, fix -Wstringop-overflow warnings, and
fix KCFI function type mismatches that went ignored by maintainers
(Gustavo A. R. Silva, Nathan Chancellor, Kees Cook)
- Remove the remaining side-effect users of ksize() by converting
dma-buf, btrfs, and coredump to using kmalloc_size_roundup(), add
more __alloc_size attributes, and introduce full testing of all
allocator functions. Finally remove the ksize() side-effect so that
each allocation-aware checker can finally behave without exceptions
- Introduce oops_limit (default 10,000) and warn_limit (default off) to
provide greater granularity of control for panic_on_oops and
panic_on_warn (Jann Horn, Kees Cook)
- Introduce overflows_type() and castable_to_type() helpers for cleaner
overflow checking
- Improve code generation for strscpy() and update str*() kern-doc
- Convert strscpy and sigphash tests to KUnit, and expand memcpy tests
- Always use a non-NULL argument for prepare_kernel_cred()
- Disable structleak plugin in FORTIFY KUnit test (Anders Roxell)
- Adjust orphan linker section checking to respect CONFIG_WERROR (Xin
Li)
- Make sure siginfo is cleared for forced SIGKILL (haifeng.xu)
- Fix um vs FORTIFY warnings for always-NULL arguments
* tag 'hardening-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (31 commits)
ksmbd: replace one-element arrays with flexible-array members
hpet: Replace one-element array with flexible-array member
um: virt-pci: Avoid GCC non-NULL warning
signal: Initialize the info in ksignal
lib: fortify_kunit: build without structleak plugin
panic: Expose "warn_count" to sysfs
panic: Introduce warn_limit
panic: Consolidate open-coded panic_on_warn checks
exit: Allow oops_limit to be disabled
exit: Expose "oops_count" to sysfs
exit: Put an upper limit on how often we can oops
panic: Separate sysctl logic from CONFIG_SMP
mm/pgtable: Fix multiple -Wstringop-overflow warnings
mm: Make ksize() a reporting-only function
kunit/fortify: Validate __alloc_size attribute results
drm/sti: Fix return type of sti_{dvo,hda,hdmi}_connector_mode_valid()
drm/fsl-dcu: Fix return type of fsl_dcu_drm_connector_mode_valid()
driver core: Add __alloc_size hint to devm allocators
overflow: Introduce overflows_type() and castable_to_type()
coredump: Proactively round up to kmalloc bucket size
...
Since Warn count is now tracked and is a fairly interesting signal, add
the entry /sys/kernel/warn_count to expose it to userspace.
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221117234328.594699-6-keescook@chromium.org
Like oops_limit, add warn_limit for limiting the number of warnings when
panic_on_warn is not set.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-doc@vger.kernel.org
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221117234328.594699-5-keescook@chromium.org
Several run-time checkers (KASAN, UBSAN, KFENCE, KCSAN, sched) roll
their own warnings, and each check "panic_on_warn". Consolidate this
into a single function so that future instrumentation can be added in
a single location.
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Gow <davidgow@google.com>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: Jann Horn <jannh@google.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: kasan-dev@googlegroups.com
Cc: linux-mm@kvack.org
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20221117234328.594699-4-keescook@chromium.org
In preparation for adding more sysctls directly in kernel/panic.c, split
CONFIG_SMP from the logic that adds sysctls.
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221117234328.594699-1-keescook@chromium.org
console_unblank() does this too (called in both places right after),
and with a lot more confidence inspiring approach to locking.
Reconstructing this story is very strange:
In b61312d353 ("oops handling: ensure that any oops is flushed to
the mtdoops console") it is claimed that a printk(" "); flushed out
the console buffer, which was removed in e3e8a75d2a ("[PATCH]
Extract and use wake_up_klogd()"). In todays kernels this is done way
earlier in console_flush_on_panic with some really nasty tricks. I
didn't bother to fully reconstruct this all, least because the call to
bust_spinlock(0); gets moved every few years, depending upon how the
wind blows (or well, who screamed loudest about the various issue each
call site caused).
Before that commit the only calls to console_unblank() where in s390
arch code.
The other side here is the console->unblank callback, which was
introduced in 2.1.31 for the vt driver. Which predates the
console_unblank() function by a lot, which was added (without users)
in 2.4.14.3. So pretty much impossible to guess at any motivation
here. Also afaict the vt driver is the only (and always was the only)
console driver implementing the unblank callback, so no idea why a
call to console_unblank() was added for the mtdooops driver - the
action actually flushing out the console buffers is done from
console_unlock() only.
Note that as prep for the s390 users the locking was adjusted in
2.5.22 (I couldn't figure out how to properly reference the BK commit
from the historical git trees) from a normal semaphore to a trylock.
Note that a copy of the direct unblank_screen() call was added to
panic() in c7c3f05e34 ("panic: avoid deadlocks in re-entrant console
drivers"), which partially inlined the bust_spinlocks(0); call.
Long story short, I have no idea why the direct call to unblank_screen
survived for so long (the infrastructure to do it properly existed for
years), nor why it wasn't removed when the console_unblank() call was
finally added. But it makes a ton more sense to finally do that than
not - it's just better encapsulation to go through the console
functions instead of doing a direct call, so let's dare. Plus it
really does not make much sense to call the only unblank
implementation there is twice, once without, and once with appropriate
locking.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Xuezhi Zhang <zhangxuezhi1@coolpad.com>
Cc: Yangxi Xiang <xyangxi5@gmail.com>
Cc: nick black <dankamongmen@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Marco Elver <elver@google.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: David Gow <davidgow@google.com>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20220830145004.430545-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This KUnit update for Linux 5.20-rc1 consists of several fixes and an
important feature to discourage running KUnit tests on production
systems. Running tests on a production system could leave the system
in a bad state. This new feature adds:
- adds a new taint type, TAINT_TEST to signal that a test has been run.
This should discourage people from running these tests on production
systems, and to make it easier to tell if tests have been run
accidentally (by loading the wrong configuration, etc.)
- several documentation and tool enhancements and fixes.
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Merge tag 'linux-kselftest-kunit-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull KUnit updates from Shuah Khan:
"This consists of several fixes and an important feature to discourage
running KUnit tests on production systems. Running tests on a
production system could leave the system in a bad state.
Summary:
- Add a new taint type, TAINT_TEST to signal that a test has been
run.
This should discourage people from running these tests on
production systems, and to make it easier to tell if tests have
been run accidentally (by loading the wrong configuration, etc)
- Several documentation and tool enhancements and fixes"
* tag 'linux-kselftest-kunit-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (29 commits)
Documentation: KUnit: Fix example with compilation error
Documentation: kunit: Add CLI args for kunit_tool
kcsan: test: Add a .kunitconfig to run KCSAN tests
kunit: executor: Fix a memory leak on failure in kunit_filter_tests
clk: explicitly disable CONFIG_UML_PCI_OVER_VIRTIO in .kunitconfig
mmc: sdhci-of-aspeed: test: Use kunit_test_suite() macro
nitro_enclaves: test: Use kunit_test_suite() macro
thunderbolt: test: Use kunit_test_suite() macro
kunit: flatten kunit_suite*** to kunit_suite** in .kunit_test_suites
kunit: unify module and builtin suite definitions
selftest: Taint kernel when test module loaded
module: panic: Taint the kernel when selftest modules load
Documentation: kunit: fix example run_kunit func to allow spaces in args
Documentation: kunit: Cleanup run_wrapper, fix x-ref
kunit: test.h: fix a kernel-doc markup
kunit: tool: Enable virtio/PCI by default on UML
kunit: tool: make --kunitconfig repeatable, blindly concat
kunit: add coverage_uml.config to enable GCOV on UML
kunit: tool: refactor internal kconfig handling, allow overriding
kunit: tool: introduce --qemu_args
...
Most in-kernel tests (such as KUnit tests) are not supposed to run on
production systems: they may do deliberately illegal things to trigger
errors, and have security implications (for example, KUnit assertions
will often deliberately leak kernel addresses).
Add a new taint type, TAINT_TEST to signal that a test has been run.
This will be printed as 'N' (originally for kuNit, as every other
sensible letter was taken.)
This should discourage people from running these tests on production
systems, and to make it easier to tell if tests have been run
accidentally (by loading the wrong configuration, etc.)
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
This reverts commit 2bb2b7b57f.
The testing of 5.19 release candidates revealed missing synchronization
between early and regular console functionality.
It would be possible to start the console kthreads later as a workaround.
But it is clear that console lock serialized console drivers between
each other. It opens a big area of possible problems that were not
considered by people involved in the development and review.
printk() is crucial for debugging kernel issues and console output is
very important part of it. The number of consoles is huge and a proper
review would take some time. As a result it need to be reverted for 5.19.
Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220623145157.21938-7-pmladek@suse.com
This reverts commit b87f02307d.
The testing of 5.19 release candidates revealed missing synchronization
between early and regular console functionality.
It would be possible to start the console kthreads later as a workaround.
But it is clear that console lock serialized console drivers between
each other. It opens a big area of possible problems that were not
considered by people involved in the development and review.
printk() is crucial for debugging kernel issues and console output is
very important part of it. The number of consoles is huge and a proper
review would take some time. As a result it need to be reverted for 5.19.
Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220623145157.21938-2-pmladek@suse.com
There are reports that the console kthreads block the global console
lock when the system is going down, for example, reboot, panic.
First part of the solution was to block kthreads in these problematic
system states so they stopped handling newly added messages.
Second part of the solution is to wait when for the kthreads when
they are actively printing. It solves the problem when a message
was printed before the system entered the problematic state and
the kthreads managed to step in.
A busy waiting has to be used because panic() can be called in any
context and in an unknown state of the scheduler.
There must be a timeout because the kthread might get stuck or sleeping
and never release the lock. The timeout 10s is an arbitrary value
inspired by the softlockup timeout.
Link: https://lore.kernel.org/r/20220610205038.GA3050413@paulmck-ThinkPad-P17-Gen-1
Link: https://lore.kernel.org/r/CAMdYzYpF4FNTBPZsEFeWRuEwSies36QM_As8osPWZSr2q-viEA@mail.gmail.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220615162805.27962-3-pmladek@suse.com
For two kernel releases now kernel/sysctl.c has been being cleaned up
slowly, since the tables were grossly long, sprinkled with tons of #ifdefs and
all this caused merge conflicts with one susbystem or another.
This tree was put together to help try to avoid conflicts with these cleanups
going on different trees at time. So nothing exciting on this pull request,
just cleanups.
I actually had this sysctl-next tree up since v5.18 but I missed sending a
pull request for it on time during the last merge window. And so these changes
have been being soaking up on sysctl-next and so linux-next for a while.
The last change was merged May 4th.
Most of the compile issues were reported by 0day and fixed.
To help avoid a conflict with bpf folks at Daniel Borkmann's request
I merged bpf-next/pr/bpf-sysctl into sysctl-next to get the effor which
moves the BPF sysctls from kernel/sysctl.c to BPF core.
Possible merge conflicts and known resolutions as per linux-next:
bfp:
https://lkml.kernel.org/r/20220414112812.652190b5@canb.auug.org.au
rcu:
https://lkml.kernel.org/r/20220420153746.4790d532@canb.auug.org.au
powerpc:
https://lkml.kernel.org/r/20220520154055.7f964b76@canb.auug.org.au
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Merge tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull sysctl updates from Luis Chamberlain:
"For two kernel releases now kernel/sysctl.c has been being cleaned up
slowly, since the tables were grossly long, sprinkled with tons of
#ifdefs and all this caused merge conflicts with one susbystem or
another.
This tree was put together to help try to avoid conflicts with these
cleanups going on different trees at time. So nothing exciting on this
pull request, just cleanups.
Thanks a lot to the Uniontech and Huawei folks for doing some of this
nasty work"
* tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (28 commits)
sched: Fix build warning without CONFIG_SYSCTL
reboot: Fix build warning without CONFIG_SYSCTL
kernel/kexec_core: move kexec_core sysctls into its own file
sysctl: minor cleanup in new_dir()
ftrace: fix building with SYSCTL=y but DYNAMIC_FTRACE=n
fs/proc: Introduce list_for_each_table_entry for proc sysctl
mm: fix unused variable kernel warning when SYSCTL=n
latencytop: move sysctl to its own file
ftrace: fix building with SYSCTL=n but DYNAMIC_FTRACE=y
ftrace: Fix build warning
ftrace: move sysctl_ftrace_enabled to ftrace.c
kernel/do_mount_initrd: move real_root_dev sysctls to its own file
kernel/delayacct: move delayacct sysctls to its own file
kernel/acct: move acct sysctls to its own file
kernel/panic: move panic sysctls to its own file
kernel/lockdep: move lockdep sysctls to its own file
mm: move page-writeback sysctls to their own file
mm: move oom_kill sysctls to their own file
kernel/reboot: move reboot sysctls to its own file
sched: Move energy_aware sysctls to topology.c
...
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Merge tag 'printk-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Offload writing printk() messages on consoles to per-console
kthreads.
It prevents soft-lockups when an extensive amount of messages is
printed. It was observed, for example, during boot of large systems
with a lot of peripherals like disks or network interfaces.
It prevents live-lockups that were observed, for example, when
messages about allocation failures were reported and a CPU handled
consoles instead of reclaiming the memory. It was hard to solve even
with rate limiting because it would need to take into account the
amount of messages and the speed of all consoles.
It is a must to have for real time. Otherwise, any printk() might
break latency guarantees.
The per-console kthreads allow to handle each console on its own
speed. Slow consoles do not longer slow down faster ones. And
printk() does not longer unpredictably slows down various code paths.
There are situations when the kthreads are either not available or
not reliable, for example, early boot, suspend, or panic. In these
situations, printk() uses the legacy mode and tries to handle
consoles immediately.
- Add documentation for the printk index.
* tag 'printk-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk, tracing: fix console tracepoint
printk: remove @console_locked
printk: extend console_lock for per-console locking
printk: add kthread console printers
printk: add functions to prefer direct printing
printk: add pr_flush()
printk: move buffer definitions into console_emit_next_record() caller
printk: refactor and rework printing logic
printk: add con_printk() macro for console details
printk: call boot_delay_msec() in printk_delay()
printk: get caller_id/timestamp after migration disable
printk: wake waiters for safe and NMI contexts
printk: wake up all waiters
printk: add missing memory barrier to wake_up_klogd()
printk: cpu sync always disable interrupts
printk: rename cpulock functions
printk/index: Printk index feature documentation
MAINTAINERS: Add printk indexing maintainers on mention of printk_index
In preparation for Clang supporting randstruct, reorganize the Kconfigs,
move the attribute macros, and generalize the feature to be named
CONFIG_RANDSTRUCT for on/off, CONFIG_RANDSTRUCT_FULL for the full
randomization mode, and CONFIG_RANDSTRUCT_PERFORMANCE for the cache-line
sized mode.
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220503205503.3054173-4-keescook@chromium.org
Once kthread printing is available, console printing will no longer
occur in the context of the printk caller. However, there are some
special contexts where it is desirable for the printk caller to
directly print out kernel messages. Using pr_flush() to wait for
threaded printers is only possible if the caller is in a sleepable
context and the kthreads are active. That is not always the case.
Introduce printk_prefer_direct_enter() and printk_prefer_direct_exit()
functions to explicitly (and globally) activate/deactivate preferred
direct console printing. The term "direct console printing" refers to
printing to all enabled consoles from the context of the printk
caller. The term "prefer" is used because this type of printing is
only best effort. If the console is currently locked or other
printers are already actively printing, the printk caller will need
to rely on the other contexts to handle the printing.
This preferred direct printing is how all printing has been handled
until now (unless it was explicitly deferred).
When kthread printing is introduced, there may be some unanticipated
problems due to kthreads being unable to flush important messages.
In order to minimize such risks, preferred direct printing is
activated for the primary important messages when the system
experiences general types of major errors. These are:
- emergency reboot/shutdown
- cpu and rcu stalls
- hard and soft lockups
- hung tasks
- warn
- sysrq
Note that since kthread printing does not yet exist, no behavior
changes result from this commit. This is only implementing the
counter and marking the various places where preferred direct
printing is active.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org> # for RCU
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220421212250.565456-13-john.ogness@linutronix.de
kernel/sysctl.c is a kitchen sink where everyone leaves their dirty
dishes, this makes it very difficult to maintain.
To help with this maintenance let's start by moving sysctls to places
where they actually belong. The proc sysctl maintainers do not want to
know what sysctl knobs you wish to add for your own piece of code, we
just care about the core logic.
All filesystem syctls now get reviewed by fs folks. This commit
follows the commit of fs, move the oops_all_cpu_backtrace sysctl to
its own file, kernel/panic.c.
Signed-off-by: tangmeng <tangmeng@uniontech.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
The panic_print setting allows users to collect more information in a
panic event, like memory stats, tasks, CPUs backtraces, etc. This is an
interesting debug mechanism, but currently the print event happens *after*
kmsg_dump(), meaning that pstore, for example, cannot collect a dmesg with
the panic_print extra information.
This patch changes that in 2 steps:
(a) The panic_print setting allows to replay the existing kernel log
buffer to the console (bit 5), besides the extra information dump.
This functionality makes sense only at the end of the panic()
function. So, we hereby allow to distinguish the two situations by a
new boolean parameter in the function panic_print_sys_info().
(b) With the above change, we can safely call panic_print_sys_info()
before kmsg_dump(), allowing to dump the extra information when using
pstore or other kmsg dumpers.
The additional messages from panic_print could overwrite the oldest
messages when the buffer is full. The only reasonable solution is to use
a large enough log buffer, hence we added an advice into the kernel
parameters documentation about that.
Link: https://lkml.kernel.org/r/20220214141308.841525-1-gpiccoli@igalia.com
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Acked-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently the "panic_print" parameter/sysctl allows some interesting debug
information to be printed during a panic event. This is useful for
example in cases the user cannot kdump due to resource limits, or if the
user collects panic logs in a serial output (or pstore) and prefers a fast
reboot instead of a kdump.
Happens that currently there's no way to see all CPUs backtraces in a
panic using "panic_print" on architectures that support that. We do have
"oops_all_cpu_backtrace" sysctl, but although partially overlapping in the
functionality, they are orthogonal in nature: "panic_print" is a panic
tuning (and we have panics without oopses, like direct calls to panic() or
maybe other paths that don't go through oops_enter() function), and the
original purpose of "oops_all_cpu_backtrace" is to provide more
information on oopses for cases in which the users desire to continue
running the kernel even after an oops, i.e., used in non-panic scenarios.
So, we hereby introduce an additional bit for "panic_print" to allow
dumping the CPUs backtraces during a panic event.
Link: https://lkml.kernel.org/r/20211109202848.610874-3-gpiccoli@igalia.com
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Reviewed-by: Feng Tang <feng.tang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the current code, the following three places need to unset
panic_on_warn before calling panic() to avoid recursive panics:
kernel/kcsan/report.c: print_report()
kernel/sched/core.c: __schedule_bug()
mm/kfence/report.c: kfence_report_error()
In order to avoid copy-pasting "panic_on_warn = 0" all over the places,
it is better to move it inside panic() and then remove it from the other
places.
Link: https://lkml.kernel.org/r/1644324666-15947-4-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
