diff options
| author | Anton Vorontsov <anton.vorontsov@linaro.org> | 2012-02-07 07:49:51 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-09 18:03:30 +0100 |
| commit | d3a532a9c617106a0169232d40164ee35d0440b5 (patch) | |
| tree | 4204ef5560c353f91cd275fb8303d799869dd97c | |
| parent | sysrq: Fix possible race with exiting task (diff) | |
| download | linux-d3a532a9c617106a0169232d40164ee35d0440b5.tar.xz linux-d3a532a9c617106a0169232d40164ee35d0440b5.zip | |
sysrq: Properly check for kernel threads
There's a real possibility of killing kernel threads that might
have issued use_mm(), so kthread's mm might become non-NULL.
This patch fixes the issue by checking for PF_KTHREAD (just as
get_task_mm()).
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/sysrq.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index a1bcad7ef739..8db9125133b8 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -324,9 +324,12 @@ static void send_sig_all(int sig) read_lock(&tasklist_lock); for_each_process(p) { - if (p->mm && !is_global_init(p)) - /* Not swapper, init nor kernel thread */ - force_sig(sig, p); + if (p->flags & PF_KTHREAD) + continue; + if (is_global_init(p)) + continue; + + force_sig(sig, p); } read_unlock(&tasklist_lock); } |