mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity
linux-stable/kernel
History
Linus Torvalds 5f0bc0b042 mm: suppress mm fault logging if fatal signal already pending 
Commit eda0047296 ("mm: make the page fault mmap locking killable")
intentionally made it much easier to trigger the "page fault fails
because a fatal signal is pending" situation, by having the mmap locking
fail early in that case.

We have long aborted page faults in other fatal cases when the actual IO
for a page is interrupted by SIGKILL - which is particularly useful for
the traditional case of NFS hanging due to network issues, but local
filesystems could cause it too if you happened to get the SIGKILL while
waiting for a page to be faulted in (eg lock_folio_maybe_drop_mmap()).

So aborting the page fault wasn't a new condition - but it now triggers
earlier, before we even get to 'handle_mm_fault()'.  And as a result the
error doesn't go through our 'fault_signal_pending()' logic, and doesn't
get filtered away there.

Normally you'd never even notice, because if a fatal signal is pending,
the new SIGSEGV we send ends up being ignored anyway.

But it turns out that there is one very noticeable exception: if you
enable 'show_unhandled_signals', the aborted page fault will be logged
in the kernel messages, and you'll get a scary line looking something
like this in your logs:

  pverados[2183248]: segfault at 55e5a00f9ae0 ip 000055e5a00f9ae0 sp 00007ffc0720bea8 error 14 in perl[55e5a00d4000+195000] likely on CPU 10 (core 4, socket 0)

which is rather misleading.  It's not really a segfault at all, it's
just "the thread was killed before the page fault completed, so we
aborted the page fault".

Fix this by just making it clear that a pending fatal signal means that
any new signal coming in after that is implicitly handled.  This will
avoid the misleading logging, since now the signal isn't 'unhandled' any
more.

Reported-and-tested-by: Fiona Ebner <f.ebner@proxmox.com>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Link: https://lore.kernel.org/lkml/8d063a26-43f5-0bb7-3203-c6a04dc159f8@proxmox.com/
Acked-by: Oleg Nesterov <oleg@redhat.com>
Fixes: eda0047296 ("mm: make the page fault mmap locking killable")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 		2023-07-26 10:51:59 -07:00
..
bpf bpf: Repeat check_max_stack_depth for async callbacks 2023-07-18 15:21:09 -07:00
cgroup sched/psi: use kernfs polling functions for PSI trigger polling 2023-07-10 09:52:30 +02:00
configs mm/slab: rename CONFIG_SLAB to CONFIG_SLAB_DEPRECATED 2023-05-26 19:01:47 +02:00
debug kdb: move kdb_send_sig() declaration to a better header file 2023-07-03 09:27:12 +01:00
dma dma-mapping fixes for Linux 6.5 2023-07-09 10:24:22 -07:00
entry ptrace: Provide set/get interface for syscall user dispatch 2023-04-16 14:23:07 +02:00
events cxl for v6.5 2023-07-01 08:58:41 -07:00
futex - Prevent the leaking of a debug timer in futex_waitv() 2023-01-01 11:15:05 -08:00
gcov gcov: add support for checksum field 2022-12-21 14:31:52 -08:00
irq irqdomain: Use return value of strreplace() 2023-06-30 11:13:44 +02:00
kcsan kcsan: Don't expect 64 bits atomic builtins from 32 bits architectures 2023-06-09 23:29:50 +10:00
livepatch livepatch: Make 'klp_stack_entries' static 2023-06-05 13:56:52 +02:00
locking - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in 2023-06-28 10:59:38 -07:00
module module: fix init_module_from_file() error handling 2023-07-04 10:17:11 -07:00
power Merge branches 'pm-sleep' and 'pm-qos' 2023-07-14 19:13:21 +02:00
printk seqlock/latch: Provide raw_read_seqcount_latch_retry() 2023-06-05 21:11:03 +02:00
rcu Merge branches 'doc.2023.05.10a', 'fixes.2023.05.11a', 'kvfree.2023.05.10a', 'nocb.2023.05.11a', 'rcu-tasks.2023.05.10a', 'torture.2023.05.15a' and 'rcu-urgent.2023.06.06a' into HEAD 2023-06-07 13:44:06 -07:00
sched sched/psi: use kernfs polling functions for PSI trigger polling 2023-07-10 09:52:30 +02:00
time hardening updates for v6.5-rc1 2023-06-27 21:24:18 -07:00
trace tracing/histograms: Return an error if we fail to add histogram to hist_vars list 2023-07-23 11:18:52 -04:00
.gitignore
…
Kconfig.freezer
…
Kconfig.hz
…
Kconfig.locks
…
Kconfig.preempt
…
Makefile v6.5-rc1-modules-next 2023-06-28 15:51:08 -07:00
acct.c acct: fix potential integer overflow in encode_comp_t() 2022-11-30 16:13:18 -08:00
async.c
…
audit.c audit: use time_after to compare time 2022-08-29 19:47:03 -04:00
audit.h audit: avoid missing-prototype warnings 2023-05-17 11:34:55 -04:00
audit_fsnotify.c audit: fix potential double free on error path from fsnotify_add_inode_mark 2022-08-22 18:50:06 -04:00
audit_tree.c
…
audit_watch.c audit_init_parent(): constify path 2022-09-01 17:39:30 -04:00
auditfilter.c
…
auditsc.c capability: just use a 'u64' instead of a 'u32[2]' array 2023-03-01 10:01:22 -08:00
backtracetest.c
…
bounds.c mm: multi-gen LRU: minimal implementation 2022-09-26 19:46:09 -07:00
capability.c capability: fix kernel-doc warnings in capability.c 2023-05-22 14:30:52 -04:00
cfi.c cfi: Switch to -fsanitize=kcfi 2022-09-26 10:13:13 -07:00
compat.c sched_getaffinity: don't assume 'cpumask_size()' is fully initialized 2023-03-14 19:32:38 -07:00
configs.c
…
context_tracking.c locking/atomic: treewide: use raw_atomic*_<op>() 2023-06-05 09:57:20 +02:00
cpu.c cpu/hotplug: Fix off by one in cpuhp_bringup_mask() 2023-05-23 18:06:40 +02:00
cpu_pm.c cpuidle, cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}() 2023-01-13 11:48:15 +01:00
crash_core.c mm, treewide: redefine MAX_ORDER sanely 2023-04-05 19:42:46 -07:00
crash_dump.c
…
cred.c cred: Do not default to init_cred in prepare_kernel_cred() 2022-11-01 10:04:52 -07:00
delayacct.c delayacct: track delays from IRQ/SOFTIRQ 2023-04-18 16:39:34 -07:00
dma.c
…
exec_domain.c
…
exit.c fork, vhost: Use CLONE_THREAD to fix freezer/ps regression 2023-06-01 17:15:33 -04:00
extable.c
…
fail_function.c kernel/fail_function: fix memory leak with using debugfs_lookup() 2023-02-08 13:36:22 +01:00
fork.c fork: lock VMAs of the parent process when forking 2023-07-08 14:08:02 -07:00
freezer.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
gen_kheaders.sh Revert "kheaders: substituting --sort in archive creation" 2023-05-28 16:20:21 +09:00
groups.c security: Add LSM hook to setgroups() syscall 2022-07-15 18:21:49 +00:00
hung_task.c kernel/hung_task.c: set some hung_task.c variables storage-class-specifier to static 2023-04-08 13:45:37 -07:00
iomem.c
…
irq_work.c trace: Add trace_ipi_send_cpu() 2023-03-24 11:01:29 +01:00
jump_label.c jump_label: Prevent key->enabled int overflow 2022-12-01 15:53:05 -08:00
kallsyms.c kallsyms: strip LTO-only suffixes from promoted global functions 2023-07-12 15:39:34 -07:00
kallsyms_internal.h kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[] 2022-11-12 18:47:36 -08:00
kallsyms_selftest.c kallsyms: Delete an unused parameter related to {module_}kallsyms_on_each_symbol() 2023-03-19 13:27:19 -07:00
kallsyms_selftest.h kallsyms: Add self-test facility 2022-11-15 00:42:02 -08:00
kcmp.c
…
kcov.c kcov: add prototypes for helper functions 2023-06-09 17:44:17 -07:00
kexec.c kexec: introduce sysctl parameters kexec_load_limit_* 2023-02-02 22:50:05 -08:00
kexec_core.c kexec: enable kexec_crash_size to support two crash kernel regions 2023-06-09 17:44:24 -07:00
kexec_elf.c
…
kexec_file.c - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in 2023-06-28 10:59:38 -07:00
kexec_internal.h panic, kexec: make __crash_kexec() NMI safe 2022-09-11 21:55:06 -07:00
kheaders.c kheaders: Use array declaration instead of char 2023-03-24 20:10:59 -07:00
kprobes.c Probes fixes and clean ups for v6.5-rc1: 2023-07-12 12:01:16 -07:00
ksyms_common.c kallsyms: make kallsyms_show_value() as generic function 2023-06-08 12:27:20 -07:00
ksysfs.c kernel/ksysfs.c: use sysfs_emit for sysfs show handlers 2023-03-24 17:09:14 +01:00
kthread.c - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in 2023-06-28 10:59:38 -07:00
latencytop.c latencytop: use the last element of latency_record of system 2022-09-11 21:55:12 -07:00
module_signature.c
…
notifier.c notifiers: add tracepoints to the notifiers infrastructure 2023-04-08 13:45:38 -07:00
nsproxy.c convert setns(2) to fdget()/fdput() 2023-04-20 22:55:35 -04:00
padata.c padata: use alignment when calculating the number of worker threads 2023-03-14 17:06:44 +08:00
panic.c panic: hide unused global functions 2023-06-09 17:44:15 -07:00
params.c kallsyms: Replace all non-returning strlcpy with strscpy 2023-06-14 12:27:38 -07:00
pid.c pid: use struct_size_t() helper 2023-07-01 08:26:23 -07:00
pid_namespace.c pid: use struct_size_t() helper 2023-07-01 08:26:23 -07:00
pid_sysctl.h kernel: pid_namespace: remove unused set_memfd_noexec_scope() 2023-06-19 16:19:28 -07:00
profile.c kernel/profile.c: simplify duplicated code in profile_setup() 2022-09-11 21:55:12 -07:00
ptrace.c ptrace: Provide set/get interface for syscall user dispatch 2023-04-16 14:23:07 +02:00
range.c
…
reboot.c kernel/reboot: Add SYS_OFF_MODE_RESTART_PREPARE mode 2022-10-04 15:59:36 +02:00
regset.c
…
relay.c relayfs: fix out-of-bounds access in relay_file_read 2023-05-02 17:23:27 -07:00
resource.c dax/kmem: Fix leak of memory-hotplug resources 2023-02-17 14:58:01 -08:00
resource_kunit.c
…
rseq.c rseq: Extend struct rseq with per-memory-map concurrency ID 2022-12-27 12:52:12 +01:00
scftorture.c
…
scs.c scs: add support for dynamic shadow call stacks 2022-11-09 18:06:35 +00:00
seccomp.c seccomp: simplify sysctls with register_sysctl_init() 2023-04-13 11:49:20 -07:00
signal.c mm: suppress mm fault logging if fatal signal already pending 2023-07-26 10:51:59 -07:00
smp.c trace,smp: Add tracepoints for scheduling remotelly called functions 2023-06-16 22:08:09 +02:00
smpboot.c cpu/hotplug: Remove unused state functions 2023-05-15 13:45:00 +02:00
smpboot.h
…
softirq.c Revert "softirq: Let ksoftirqd do its job" 2023-05-09 21:50:27 +02:00
stackleak.c stackleak: allow to specify arch specific stackleak poison function 2023-04-20 11:36:35 +02:00
stacktrace.c
…
static_call.c
…
static_call_inline.c static_call: Add call depth tracking support 2022-10-17 16:41:16 +02:00
stop_machine.c
…
sys.c prctl: move PR_GET_AUXV out of PR_MCE_KILL 2023-07-17 12:53:21 -07:00
sys_ni.c asm-generic updates for 6.5 2023-07-06 10:06:04 -07:00
sysctl-test.c kernel/sysctl-test: use SYSCTL_{ZERO/ONE_HUNDRED} instead of i_{zero/one_hundred} 2022-09-08 16:56:45 -07:00
sysctl.c v6.5-rc1-sysctl-next 2023-06-28 16:05:21 -07:00
task_work.c task_work: use try_cmpxchg in task_work_add, task_work_cancel_match and task_work_run 2022-09-11 21:55:10 -07:00
taskstats.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
torture.c torture: Fix hang during kthread shutdown phase 2023-01-05 12:10:35 -08:00
tracepoint.c tracepoint: Allow livepatch module add trace event 2023-02-18 14:34:36 -05:00
tsacct.c
…
ucount.c
…
uid16.c
…
uid16.h
…
umh.c sysctl: fix unused proc_cap_handler() function warning 2023-06-29 15:19:43 -07:00
up.c
…
user-return-notifier.c
…
user.c kernel/user: Allow user_struct::locked_vm to be usable for iommufd 2022-11-30 20:16:49 -04:00
user_namespace.c userns: fix a struct's kernel-doc notation 2023-02-02 22:50:04 -08:00
usermode_driver.c
…
utsname.c
…
utsname_sysctl.c utsname: simplify one-level sysctl registration for uts_kern_table 2023-04-13 11:49:35 -07:00
vhost_task.c vhost: Fix worker hangs due to missed wake up calls 2023-06-08 15:43:09 -04:00
watch_queue.c watch_queue: prevent dangling pipe pointer 2023-06-06 10:47:04 +02:00
watchdog.c watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64 2023-06-19 16:25:29 -07:00
watchdog_buddy.c watchdog/hardlockup: move SMP barriers from common code to buddy code 2023-06-19 16:25:28 -07:00
watchdog_perf.c watchdog/perf: add a weak function for an arch to detect if perf can use NMIs 2023-06-09 17:44:21 -07:00
workqueue.c workqueue: Changes for v6.5 2023-06-27 16:32:52 -07:00
workqueue_internal.h workqueue: Automatically mark CPU-hogging work items CPU_INTENSIVE 2023-05-17 17:02:08 -10:00