i915 will soon gain an eviction path that trylock a whole lot of locks
for eviction, getting dmesg failures like below:
BUG: MAX_LOCK_DEPTH too low!
turning off the locking correctness validator.
depth: 48 max: 48!
48 locks held by i915_selftest/5776:
#0: ffff888101a79240 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x88/0x160
#1: ffffc900009778c0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.63+0x39/0x1b0 [i915]
#2: ffff88800cf74de8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.63+0x5f/0x1b0 [i915]
#3: ffff88810c7f9e38 (&vm->mutex/1){+.+.}-{3:3}, at: i915_vma_pin_ww+0x1c4/0x9d0 [i915]
#4: ffff88810bad5768 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
#5: ffff88810bad60e8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
...
#46: ffff88811964d768 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
#47: ffff88811964e0e8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
INFO: lockdep is turned off.
Fixing eviction to nest into ww_class_acquire is a high priority, but
it requires a rework of the entire driver, which can only be done one
step at a time.
As an intermediate solution, add an acquire context to
ww_mutex_trylock, which allows us to do proper nesting annotations on
the trylocks, making the above lockdep splat disappear.
This is also useful in regulator_lock_nested, which may avoid dropping
regulator_nesting_mutex in the uncontended path, so use it there.
TTM may be another user for this, where we could lock a buffer in a
fastpath with list locks held, without dropping all locks we hold.
[peterz: rework actual ww_mutex_trylock() implementations]
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/YUBGPdDDjKlxAuXJ@hirez.programming.kicks-ass.net
Pull tracing fixes from Steven Rostedt:
"Minor fixes to the processing of the bootconfig tree"
* tag 'trace-v5.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
bootconfig: Rename xbc_node_find_child() to xbc_node_find_subkey()
tracing/boot: Fix to check the histogram control param is a leaf node
tracing/boot: Fix trace_boot_hist_add_array() to check array is value
Rename xbc_node_find_child() to xbc_node_find_subkey() for
clarifying that function returns a key node (no value node).
Since there are xbc_node_for_each_child() (loop on all child
nodes) and xbc_node_for_each_subkey() (loop on only subkey
nodes), this name distinction is necessary to avoid confusing
users.
Link: https://lkml.kernel.org/r/163119459826.161018.11200274779483115300.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull UML updates from Richard Weinberger:
- Support for VMAP_STACK
- Support for splice_write in hostfs
- Fixes for virt-pci
- Fixes for virtio_uml
- Various fixes
* tag 'for-linus-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: fix stub location calculation
um: virt-pci: fix uapi documentation
um: enable VMAP_STACK
um: virt-pci: don't do DMA from stack
hostfs: support splice_write
um: virtio_uml: fix memory leak on init failures
um: virtio_uml: include linux/virtio-uml.h
lib/logic_iomem: fix sparse warnings
um: make PCI emulation driver init/exit static
Merge more updates from Andrew Morton:
"147 patches, based on 7d2a07b769.
Subsystems affected by this patch series: mm (memory-hotplug, rmap,
ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
selftests, ipc, and scripts"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
scripts: check_extable: fix typo in user error message
mm/workingset: correct kernel-doc notations
ipc: replace costly bailout check in sysvipc_find_ipc()
selftests/memfd: remove unused variable
Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
configs: remove the obsolete CONFIG_INPUT_POLLDEV
prctl: allow to setup brk for et_dyn executables
pid: cleanup the stale comment mentioning pidmap_init().
kernel/fork.c: unexport get_{mm,task}_exe_file
coredump: fix memleak in dump_vma_snapshot()
fs/coredump.c: log if a core dump is aborted due to changed file permissions
nilfs2: use refcount_dec_and_lock() to fix potential UAF
nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
nilfs2: fix NULL pointer in nilfs_##name##_attr_release
nilfs2: fix memory leak in nilfs_sysfs_create_device_group
trap: cleanup trap_init()
init: move usermodehelper_enable() to populate_rootfs()
...
Fix all kernel-doc warnings in lib/iov_iter.c:
lib/iov_iter.c:695: warning: Function parameter or member 'i' not described in '_copy_mc_to_iter'
lib/iov_iter.c:695: warning: Excess function parameter 'iter' description in '_copy_mc_to_iter'
lib/iov_iter.c:695: warning: No description found for return value of '_copy_mc_to_iter'
lib/iov_iter.c:758: warning: Function parameter or member 'i' not described in '_copy_from_iter_flushcache'
lib/iov_iter.c:758: warning: Excess function parameter 'iter' description in '_copy_from_iter_flushcache'
lib/iov_iter.c:758: warning: No description found for return value of '_copy_from_iter_flushcache'
Link: https://lkml.kernel.org/r/20210809051053.6531-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This follows up commit ebd09577be ("lib/test: convert
lib/test_list_sort.c to use KUnit").
Converting this test to KUnit makes the test a bit shorter, standardizes
how it reports pass/fail, and adds an easier way to run the test [1].
Like ebd09577be, this leaves the file and Kconfig option name the same,
but slightly changes their dependencies (needs CONFIG_KUNIT).
[1] Can be run via
$ ./tools/testing/kunit/kunit.py run --kunitconfig /dev/stdin <<EOF
CONFIG_KUNIT=y
CONFIG_TEST_SORT=y
EOF
[11:30:27] Starting KUnit Kernel ...
[11:30:30] ============================================================
[11:30:30] ======== [PASSED] lib_sort ========
[11:30:30] [PASSED] test_sort
[11:30:30] ============================================================
[11:30:30] Testing complete. 1 tests run. 0 failed. 0 crashed. 0 skipped.
[11:30:30] Elapsed time: 37.032s total, 0.001s configuring, 34.090s building, 0.000s running
Note: this is the time it took after a `make mrproper`.
With an incremental rebuild, this looks more like:
[11:38:58] Elapsed time: 6.444s total, 0.001s configuring, 3.416s building, 0.000s running
Since the test has no dependencies, it can also be run (with some other
tests) with just:
$ ./tools/testing/kunit/kunit.py run
Link: https://lkml.kernel.org/r/20210715232441.1380885-1-dlatypov@google.com
Signed-off-by: Daniel Latypov <dlatypov@google.com>
Cc: Pravin Shedge <pravin.shedge4linux@gmail.com>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turns out that gcc has real trouble merging all the temporary
on-stack buffer allocation. So despite the fact that their lifetimes do
not overlap, gcc will allocate stack for all of them when they have
different types. Which they do in the number scanning test routines.
This is unfortunate in general, but with lots of test-cases in one
function, it becomes a real problem. gcc will allocate a huge stack
frame for no actual good reason.
We have tried to counteract this tendency of gcc not merging stack slots
(see "-fconserve-stack"), but that has limited effect (and should be on
by default these days, iirc).
So with all the debug options enabled on an i386 allmodconfig build, we
end up with overly big stack frames, and the resulting stack frame size
warnings (now errors):
lib/test_scanf.c: In function ‘numbers_list_field_width_val_width’:
lib/test_scanf.c:530:1: error: the frame size of 2088 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
530 | }
| ^
lib/test_scanf.c: In function ‘numbers_list_field_width_typemax’:
lib/test_scanf.c:488:1: error: the frame size of 2568 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
488 | }
| ^
lib/test_scanf.c: In function ‘numbers_list’:
lib/test_scanf.c:437:1: error: the frame size of 2088 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
437 | }
| ^
In this particular case, the reasonably straightforward solution is to
just split out the test routines into multiple more targeted versions.
That way we don't have one huge stack, but several smaller ones, and
they aren't active all at the same time.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull MAP_DENYWRITE removal from David Hildenbrand:
"Remove all in-tree usage of MAP_DENYWRITE from the kernel and remove
VM_DENYWRITE.
There are some (minor) user-visible changes:
- We no longer deny write access to shared libaries loaded via legacy
uselib(); this behavior matches modern user space e.g. dlopen().
- We no longer deny write access to the elf interpreter after exec
completed, treating it just like shared libraries (which it often
is).
- We always deny write access to the file linked via /proc/pid/exe:
sys_prctl(PR_SET_MM_MAP/EXE_FILE) will fail if write access to the
file cannot be denied, and write access to the file will remain
denied until the link is effectivel gone (exec, termination,
sys_prctl(PR_SET_MM_MAP/EXE_FILE)) -- just as if exec'ing the file.
Cross-compiled for a bunch of architectures (alpha, microblaze, i386,
s390x, ...) and verified via ltp that especially the relevant tests
(i.e., creat07 and execve04) continue working as expected"
* tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux:
fs: update documentation of get_write_access() and friends
mm: ignore MAP_DENYWRITE in ksys_mmap_pgoff()
mm: remove VM_DENYWRITE
binfmt: remove in-tree usage of MAP_DENYWRITE
kernel/fork: always deny write access to current MM exe_file
kernel/fork: factor out replacing the current MM exe_file
binfmt: don't use MAP_DENYWRITE when loading shared libraries via uselib()
Pull Kbuild updates from Masahiro Yamada:
- Add -s option (strict mode) to merge_config.sh to make it fail when
any symbol is redefined.
- Show a warning if a different compiler is used for building external
modules.
- Infer --target from ARCH for CC=clang to let you cross-compile the
kernel without CROSS_COMPILE.
- Make the integrated assembler default (LLVM_IAS=1) for CC=clang.
- Add <linux/stdarg.h> to the kernel source instead of borrowing
<stdarg.h> from the compiler.
- Add Nick Desaulniers as a Kbuild reviewer.
- Drop stale cc-option tests.
- Fix the combination of CONFIG_TRIM_UNUSED_KSYMS and CONFIG_LTO_CLANG
to handle symbols in inline assembly.
- Show a warning if 'FORCE' is missing for if_changed rules.
- Various cleanups
* tag 'kbuild-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
kbuild: redo fake deps at include/ksym/*.h
kbuild: clean up objtool_args slightly
modpost: get the *.mod file path more simply
checkkconfigsymbols.py: Fix the '--ignore' option
kbuild: merge vmlinux_link() between ARCH=um and other architectures
kbuild: do not remove 'linux' link in scripts/link-vmlinux.sh
kbuild: merge vmlinux_link() between the ordinary link and Clang LTO
kbuild: remove stale *.symversions
kbuild: remove unused quiet_cmd_update_lto_symversions
gen_compile_commands: extract compiler command from a series of commands
x86: remove cc-option-yn test for -mtune=
arc: replace cc-option-yn uses with cc-option
s390: replace cc-option-yn uses with cc-option
ia64: move core-y in arch/ia64/Makefile to arch/ia64/Kbuild
sparc: move the install rule to arch/sparc/Makefile
security: remove unneeded subdir-$(CONFIG_...)
kbuild: sh: remove unused install script
kbuild: Fix 'no symbols' warning when CONFIG_TRIM_UNUSD_KSYMS=y
kbuild: Switch to 'f' variants of integrated assembler flag
kbuild: Shuffle blank line to improve comment meaning
...
Merge misc updates from Andrew Morton:
"173 patches.
Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
oom-kill, migration, ksm, percpu, vmstat, and madvise)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
mm/madvise: add MADV_WILLNEED to process_madvise()
mm/vmstat: remove unneeded return value
mm/vmstat: simplify the array size calculation
mm/vmstat: correct some wrong comments
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
selftests: vm: add COW time test for KSM pages
selftests: vm: add KSM merging time test
mm: KSM: fix data type
selftests: vm: add KSM merging across nodes test
selftests: vm: add KSM zero page merging test
selftests: vm: add KSM unmerge test
selftests: vm: add KSM merge test
mm/migrate: correct kernel-doc notation
mm: wire up syscall process_mrelease
mm: introduce process_mrelease system call
memblock: make memblock_find_in_range method private
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
...
Patch series "kasan: test: avoid crashing the kernel with HW_TAGS", v2.
KASAN tests do out-of-bounds and use-after-free accesses. Running the
tests works fine for the GENERIC mode, as it uses qurantine and redzones.
But the HW_TAGS mode uses neither, and running the tests might crash the
kernel.
Rework the tests to avoid corrupting kernel memory.
This patch (of 8):
Rework kmalloc_oob_right() to do these bad access checks:
1. An unaligned access one byte past the requested kmalloc size
(can only be detected by KASAN_GENERIC).
2. An aligned access into the first out-of-bounds granule that falls
within the aligned kmalloc object.
3. Out-of-bounds access past the aligned kmalloc object.
Test #3 deliberately uses a read access to avoid corrupting memory.
Otherwise, this test might lead to crashes with the HW_TAGS mode, as it
neither uses quarantine nor redzones.
Link: https://lkml.kernel.org/r/cover.1628779805.git.andreyknvl@gmail.com
Link: https://lkml.kernel.org/r/474aa8b7b538c6737a4c6d0090350af2e1776bef.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Maarten Lankhorst
Linus Torvalds
Masami Hiramatsu
Lukas Bulwahn
Randy Dunlap
Daniel Latypov
Geert Uytterhoeven
Muchun Song
Andrey Konovalov
Uladzislau Rezki (Sony)