diff options
| author | Andrey Ryabinin <aryabinin@virtuozzo.com> | 2016-11-10 10:46:38 -0800 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2017-02-23 03:51:00 +0000 |
| commit | 5065c7059125e6ddb122535b1fa70af740294d88 (patch) | |
| tree | eb2d5da1da0e8028336b618519c994d752b18c4f /fs | |
| parent | 77d745a108e548e11bc0f2297e853127908c2a10 (diff) | |
coredump: fix unfreezable coredumping task
commit 70d78fe7c8b640b5acfad56ad341985b3810998a upstream.
It could be not possible to freeze coredumping task when it waits for
'core_state->startup' completion, because threads are frozen in
get_signal() before they got a chance to complete 'core_state->startup'.
Inability to freeze a task during suspend will cause suspend to fail.
Also CRIU uses cgroup freezer during dump operation. So with an
unfreezable task the CRIU dump will fail because it waits for a
transition from 'FREEZING' to 'FROZEN' state which will never happen.
Use freezer_do_not_count() to tell freezer to ignore coredumping task
while it waits for core_state->startup completion.
Link: http://lkml.kernel.org/r/1475225434-3753-1-git-send-email-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/exec.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/exec.c b/fs/exec.c index a0006d85785c..3f8d8f331a98 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -25,6 +25,7 @@ #include <linux/slab.h> #include <linux/file.h> #include <linux/fdtable.h> +#include <linux/freezer.h> #include <linux/mm.h> #include <linux/stat.h> #include <linux/fcntl.h> @@ -1974,8 +1975,11 @@ static int coredump_wait(int exit_code, struct core_state *core_state) complete(vfork_done); } - if (core_waiters) + if (core_waiters > 0) { + freezer_do_not_count(); wait_for_completion(&core_state->startup); + freezer_count(); + } fail: return core_waiters; } |