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
acct.c	acct: fix potential integer overflow in encode_comp_t()	2022-11-30 16:13:18 -08:00
async.c
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: use fsnotify group lock helpers	2022-04-25 14:37:28 +02:00
audit_watch.c	audit_init_parent(): constify path	2022-09-01 17:39:30 -04:00
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
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_pm.c	cpuidle, cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}()	2023-01-13 11:48:15 +01:00
cpu.c	cpu/hotplug: Fix off by one in cpuhp_bringup_mask()	2023-05-23 18:06:40 +02:00
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	context_tracking: Take NMI eqs entrypoints over RCU	2022-07-05 13:32:59 -07:00
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_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
kallsyms.c	kallsyms: strip LTO-only suffixes from promoted global functions	2023-07-12 15:39:34 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c	kcov: add prototypes for helper functions	2023-06-09 17:44:17 -07:00
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
kexec.c	kexec: introduce sysctl parameters kexec_load_limit_*	2023-02-02 22:50:05 -08:00
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
Makefile	v6.5-rc1-modules-next	2023-06-28 15:51:08 -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_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
pid.c	pid: use struct_size_t() helper	2023-07-01 08:26:23 -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_kunit.c
resource.c	dax/kmem: Fix leak of memory-hotplug resources	2023-02-17 14:58:01 -08:00
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_inline.c	static_call: Add call depth tracking support	2022-10-17 16:41:16 +02:00
static_call.c
stop_machine.c	Scheduler changes in this cycle were:	2022-05-24 11:11:13 -07:00
sys_ni.c	asm-generic updates for 6.5	2023-07-06 10:06:04 -07:00
sys.c	prctl: move PR_GET_AUXV out of PR_MCE_KILL	2023-07-17 12:53:21 -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	taskstats: version 12 with thread group and exe info	2022-04-29 14:38:03 -07:00
ucount.c	ucounts: Split rlimit and ucount values and max values	2022-05-18 18:24:57 -05:00
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_namespace.c	userns: fix a struct's kernel-doc notation	2023-02-02 22:50:04 -08:00
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
usermode_driver.c	blob_to_mnt(): kern_unmount() is needed to undo kern_mount()	2022-05-19 23:25:47 -04:00
utsname_sysctl.c	utsname: simplify one-level sysctl registration for uts_kern_table	2023-04-13 11:49:35 -07:00
utsname.c
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_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
watchdog.c	watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64	2023-06-19 16:25:29 -07:00
workqueue_internal.h	workqueue: Automatically mark CPU-hogging work items CPU_INTENSIVE	2023-05-17 17:02:08 -10:00
workqueue.c	workqueue: Changes for v6.5	2023-06-27 16:32:52 -07:00