From 5375b708f2547f70cd2bee2fd8663ab7035f9551 Mon Sep 17 00:00:00 2001 From: HATAYAMA Daisuke Date: Tue, 30 Jun 2015 14:57:46 -0700 Subject: kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path Commit f06e5153f4ae2e ("kernel/panic.c: add "crash_kexec_post_notifiers" option for kdump after panic_notifers") introduced "crash_kexec_post_notifiers" kernel boot option, which toggles wheather panic() calls crash_kexec() before panic_notifiers and dump kmsg or after. The problem is that the commit overlooks panic_on_oops kernel boot option. If it is enabled, crash_kexec() is called directly without going through panic() in oops path. To fix this issue, this patch adds a check to "crash_kexec_post_notifiers" in the condition of kexec_should_crash(). Also, put a comment in kexec_should_crash() to explain not obvious things on this patch. Signed-off-by: HATAYAMA Daisuke Acked-by: Baoquan He Tested-by: Hidehiro Kawai Reviewed-by: Masami Hiramatsu Cc: Vivek Goyal Cc: Ingo Molnar Cc: Hidehiro Kawai Cc: Baoquan He Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kexec.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'kernel/kexec.c') diff --git a/kernel/kexec.c b/kernel/kexec.c index 7a36fdcca5bf..a785c1015e25 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -84,6 +84,17 @@ struct resource crashk_low_res = { int kexec_should_crash(struct task_struct *p) { + /* + * If crash_kexec_post_notifiers is enabled, don't run + * crash_kexec() here yet, which must be run after panic + * notifiers in panic(). + */ + if (crash_kexec_post_notifiers) + return 0; + /* + * There are 4 panic() calls in do_exit() path, each of which + * corresponds to each of these 4 conditions. + */ if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops) return 1; return 0; -- cgit v1.2.3