Oleg Nesterov cf4b8c39b9 fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats ... [ Upstream commit 7601df8031 ] lock_task_sighand() can trigger a hard lockup. If NR_CPUS threads call do_task_stat() at the same time and the process has NR_THREADS, it will spin with irqs disabled O(NR_CPUS * NR_THREADS) time. Change do_task_stat() to use sig->stats_lock to gather the statistics outside of ->siglock protected section, in the likely case this code will run lockless. Link: https://lkml.kernel.org/r/20240123153357.GA21857@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Dylan Hatch <dylanbhatch@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2024-03-15 10:48:22 -04:00
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Kconfig	…
Makefile	…
array.c	fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats	2024-03-15 10:48:22 -04:00
base.c	procfs: block chmod on /proc/thread-self/comm	2023-09-13 09:43:02 +02:00
bootconfig.c	…
cmdline.c	…
consoles.c	…
cpuinfo.c	…
devices.c	…
fd.c	…
fd.h	…
generic.c	…
inode.c	…
internal.h	proc: nommu: fix empty /proc/<pid>/maps	2023-10-06 14:56:42 +02:00
interrupts.c	…
kcore.c	…
kmsg.c	printk changes for 6.1	2022-10-10 11:24:19 -07:00
loadavg.c	…
meminfo.c	proc/meminfo: fix spacing in SecPageTables	2022-11-22 18:50:44 -08:00
namespaces.c	…
nommu.c	…
page.c	…
proc_net.c	…
proc_sysctl.c	watchdog: move softlockup_panic back to early_param	2023-11-28 17:07:09 +00:00
proc_tty.c	…
root.c	…
self.c	…
softirqs.c	…
stat.c	…
task_mmu.c	mm: hugetlb: proc: check for hugetlb shared PMD in /proc/PID/smaps	2023-02-09 11:28:20 +01:00
task_nommu.c	proc: nommu: fix empty /proc/<pid>/maps	2023-10-06 14:56:42 +02:00
thread_self.c	…
uptime.c	…
util.c	…
version.c	…
vmcore.c	proc/vmcore: fix signedness bug in read_from_oldmem()	2023-08-03 10:24:14 +02:00