The commit f06e5153f4ae2e2f3b0300f0e260e40cb7fefd45 introduced
"crash_kexec_post_notifiers" kernel boot option, which toggles
wheather panic() calls crash_kexec() before or after panic_notifiers
and dump kmsg.
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().
Signed-off-by: HATAYAMA Daisuke <d.hatayama at jp.fujitsu.com>
---
include/linux/kernel.h | 3 +++
kernel/kexec.c | 2 ++
kernel/panic.c | 2 +-
3 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 64ce58b..f47379f 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -426,6 +426,9 @@ extern int panic_on_unrecovered_nmi;
extern int panic_on_io_nmi;
extern int panic_on_warn;
extern int sysctl_panic_on_stackoverflow;
+
+extern bool crash_kexec_post_notifiers;
+
/*
* Only to be used by arch init code. If the user over-wrote the default
* CONFIG_PANIC_TIMEOUT, honor it.
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 9a8a01a..0ecf252 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -84,6 +84,8 @@ struct resource crashk_low_res = {
int kexec_should_crash(struct task_struct *p)
{
+ if (crash_kexec_post_notifiers)
+ return 0;
if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
return 1;
return 0;
diff --git a/kernel/panic.c b/kernel/panic.c
index 4d8d6f9..6582546 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -32,7 +32,7 @@ static unsigned long tainted_mask;
static int pause_on_oops;
static int pause_on_oops_flag;
static DEFINE_SPINLOCK(pause_on_oops_lock);
-static bool crash_kexec_post_notifiers;
+bool crash_kexec_post_notifiers;
int panic_on_warn __read_mostly;
int panic_timeout = CONFIG_PANIC_TIMEOUT;
--
1.9.3
