Re: [PATCH v4 3/4] MIPS: Return earlier in die() if notify_die() returns NOTIFY_STOP

From: Tiezhu Yang
Date: Tue Aug 22 2023 - 04:55:33 EST




On 08/22/2023 03:38 PM, Huacai Chen wrote:
On Mon, Aug 21, 2023 at 10:29 AM Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> wrote:



On 08/20/2023 04:53 PM, Huacai Chen wrote:
Hi, Tiezhu,

On Sun, Aug 20, 2023 at 7:21 AM Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> wrote:

After the call to oops_exit(), it should not panic or execute
the crash kernel if the oops is to be suppressed.

Suggested-by: Maciej W. Rozycki <macro@xxxxxxxxxxx>
Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
arch/mips/kernel/traps.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 8e528a8..fd770dc 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -412,6 +412,9 @@ void die(const char *str, struct pt_regs *regs)

oops_exit();

+ if (ret == NOTIFY_STOP)
+ return;
+
if (in_interrupt())
panic("Fatal exception in interrupt");

@@ -421,8 +424,7 @@ void die(const char *str, struct pt_regs *regs)
if (regs && kexec_should_crash(current))
crash_kexec(regs);

- if (ret != NOTIFY_STOP)
- make_task_dead(SIGSEGV);
+ make_task_dead(SIGSEGV);
Then you call make_task_dead() at the end unconditionally, and die()
becomes a noreturn function again.

No, it can return if (ret == NOTIFY_STOP), so die() is a return
function now, please see objdump -d arch/mips/kernel/traps.o.
Then should loongarch patches need to be updated, too?

Yes, I think so, will do it.

Thanks,
Tiezhu