Michal Hocko b2b469939e proc, oom: do not report alien mms when setting oom_score_adj ... Tetsuo has reported that creating a thousands of processes sharing MM without SIGHAND (aka alien threads) and setting /proc/<pid>/oom_score_adj will swamp the kernel log and takes ages [1] to finish. This is especially worrisome that all that printing is done under RCU lock and this can potentially trigger RCU stall or softlockup detector. The primary reason for the printk was to catch potential users who might depend on the behavior prior to 44a70adec9 ("mm, oom_adj: make sure processes sharing mm have same view of oom_score_adj") but after more than 2 years without a single report I guess it is safe to simply remove the printk altogether. The next step should be moving oom_score_adj over to the mm struct and remove all the tasks crawling as suggested by [2] [1] http://lkml.kernel.org/r/97fce864-6f75-bca5-14bc-12c9f890e740@i-love.sakura.ne.jp [2] http://lkml.kernel.org/r/20190117155159.GA4087@dhcp22.suse.cz Link: http://lkml.kernel.org/r/20190212102129.26288-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Cc: Yong-Taek Lee <ytk.lee@samsung.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2019-02-21 09:01:00 -08:00
..
array.c	mm, proc: report PR_SET_THP_DISABLE in proc	2018-12-28 12:11:50 -08:00
base.c	proc, oom: do not report alien mms when setting oom_score_adj	2019-02-21 09:01:00 -08:00
cmdline.c
consoles.c
cpuinfo.c
devices.c
fd.c	proc: use "unsigned int" in proc_fill_cache()	2018-06-07 17:34:38 -07:00
fd.h
generic.c	proc: fix /proc/net/* after setns(2)	2019-02-01 15:46:22 -08:00
inode.c	fs/proc/inode.c: delete unnecessary variable in proc_alloc_inode()	2019-01-04 13:13:45 -08:00
internal.h	proc: fix /proc/net/* after setns(2)	2019-02-01 15:46:22 -08:00
interrupts.c
Kconfig	proc/kcore: add vmcoreinfo note to /proc/kcore	2018-08-22 10:52:46 -07:00
kcore.c	mm: remove include/linux/bootmem.h	2018-10-31 08:54:16 -07:00
kmsg.c
loadavg.c	sched: loadavg: consolidate LOAD_INT, LOAD_FRAC, CALC_LOAD	2018-10-26 16:26:32 -07:00
Makefile
meminfo.c	mm, proc: add KReclaimable to /proc/meminfo	2018-10-26 16:26:32 -07:00
namespaces.c	procfs: switch instantiate_t to d_splice_alias()	2018-05-26 14:20:50 -04:00
nommu.c
page.c	/proc/kpagecount: return 0 for special pages that are never mapped	2018-12-28 12:11:50 -08:00
proc_net.c	proc: fix /proc/net/* after setns(2)	2019-02-01 15:46:22 -08:00
proc_sysctl.c	proc/sysctl: don't return ENOMEM on lookup when a table is unregistering	2018-12-13 20:59:44 -05:00
proc_tty.c
root.c	proc: Make inline name size calculation automatic	2018-06-15 00:48:57 -04:00
self.c
softirqs.c
stat.c	proc: use "unsigned int" in /proc/stat hook	2018-08-22 10:52:46 -07:00
task_mmu.c	mm: proc: smaps_rollup: fix pss_locked calculation	2019-02-12 16:33:18 -08:00
task_nommu.c	mm: /proc/pid/*maps remove is_pid and related wrappers	2018-08-22 10:52:44 -07:00
thread_self.c
uptime.c	fs/proc/uptime.c: use ktime_get_boottime_ts64	2018-08-22 10:52:45 -07:00
util.c	fs/proc/util.c: include fs/proc/internal.h for name_to_int()	2019-01-04 13:13:45 -08:00
version.c
vmcore.c	mm: remove include/linux/bootmem.h	2018-10-31 08:54:16 -07:00