Oleg Nesterov cf4b8c39b9 fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats ... [ Upstream commit 7601df8031fd67310af891897ef6cc0df4209305 ] 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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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
bootconfig.c
cmdline.c
consoles.c
cpuinfo.c
devices.c
fd.c
fd.h
generic.c
inode.c
internal.h
interrupts.c
Kconfig
kcore.c
kmsg.c
loadavg.c
Makefile
meminfo.c
namespaces.c
nommu.c
page.c
proc_net.c
proc_sysctl.c
proc_tty.c
root.c
self.c
softirqs.c
stat.c
task_mmu.c
task_nommu.c
thread_self.c
uptime.c
util.c
version.c
vmcore.c