[PATCH] mm, memory_failure: only send BUS_MCEERR_AO to early-kill process

Wetp Zhang
2020-05-26T07:06:55Z

From: Zhang Yi <wetpzy@gmail.com>

If a process don't need early-kill, it may not care the BUS_MCEERR_AO.
Let the process to be killed when it really access the corrupted memory.

Signed-off-by: Zhang Yi <wetpzy@gmail.com>
---
mm/memory-failure.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index a96364be8ab4..2db13d48865c 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -210,7 +210,7 @@ static int kill_proc(struct to_kill *tk, unsigned long pfn, int flags)
{
struct task_struct *t = tk->tsk;
short addr_lsb = tk->size_shift;
- int ret;
+ int ret = 0;

pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due to hardware memory corruption\n",
pfn, t->comm, t->pid);
@@ -225,8 +225,9 @@ static int kill_proc(struct to_kill *tk, unsigned long pfn, int flags)
* This could cause a loop when the user sets SIGBUS
* to SIG_IGN, but hopefully no one will do that?
*/
- ret = send_sig_mceerr(BUS_MCEERR_AO, (void __user *)tk->addr,
- addr_lsb, t); /* synchronous? */
+ if ((t->flags & PF_MCE_PROCESS) && (t->flags & PF_MCE_EARLY))
+ ret = send_sig_mceerr(BUS_MCEERR_AO,
+ (void __user *)tk->addr, addr_lsb, t);
}
if (ret < 0)
pr_info("Memory failure: Error sending signal to %s:%d: %d\n",
--
2.14.3 (Apple Git-98)