Re: [PATCH] mm: hwpoison: use do_send_sig_info() instead of force_sig() (Re: PMEM error-handling forces SIGKILL causes kernel panic)

Jane Chu <jane.chu@xxxxxxxxxx> · Wed, 16 Jan 2019 17:07:09 -0800

On 1/16/2019 3:32 PM, Naoya Horiguchi wrote:
Hi Jane,

On Wed, Jan 16, 2019 at 09:56:02AM -0800, Jane Chu wrote:
Hi, Naoya,

On 1/16/2019 1:30 AM, Naoya Horiguchi wrote:

     diff --git a/mm/memory-failure.c b/mm/memory-failure.c
     index 7c72f2a95785..831be5ff5f4d 100644
     --- a/mm/memory-failure.c
     +++ b/mm/memory-failure.c
     @@ -372,7 +372,8 @@ static void kill_procs(struct list_head *to_kill, int forcekill, bool fail,
                             if (fail || tk->addr_valid == 0) {
                                     pr_err("Memory failure: %#lx: forcibly killing %s:%d because of failure to unmap corrupted page\n",
                                            pfn, tk->tsk->comm, tk->tsk->pid);
     -                               force_sig(SIGKILL, tk->tsk);
     +                               do_send_sig_info(SIGKILL, SEND_SIG_PRIV,
     +                                                tk->tsk, PIDTYPE_PID);
                             }

Since we don't care the return from do_send_sig_info(), would you mind to
prefix it with (void) ?

Sorry, I'm not sure about the benefit to do casting the return value
just being ignored, so personally I'd like keeping the code simple.
Do you have some in mind?

It's just coding style I'm used to, no big deal.
Up to you to decide. :)

thanks,
-jane

- Naoya