[PATCH 3/8] mm/memory-failure.c: rework the signaling logic in kill_proc

From: Miaohe Lin
Date: Thu Feb 10 2022 - 09:21:29 EST


BUS_MCEERR_AR code is only sent when MF_ACTION_REQUIRED is set and the
target is current. Rework the code to make this clear.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/memory-failure.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index f86819145ea8..2dd7f35ee65a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -258,16 +258,13 @@ static int kill_proc(struct to_kill *tk, unsigned long pfn, int flags)
pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due to hardware memory corruption\n",
pfn, t->comm, t->pid);

- if (flags & MF_ACTION_REQUIRED) {
- if (t == current)
- ret = force_sig_mceerr(BUS_MCEERR_AR,
- (void __user *)tk->addr, addr_lsb);
- else
- /* Signal other processes sharing the page if they have PF_MCE_EARLY set. */
- ret = send_sig_mceerr(BUS_MCEERR_AO, (void __user *)tk->addr,
- addr_lsb, t);
- } else {
+ if ((flags & MF_ACTION_REQUIRED) && (t == current))
+ ret = force_sig_mceerr(BUS_MCEERR_AR,
+ (void __user *)tk->addr, addr_lsb);
+ else
/*
+ * Signal other processes sharing the page if they have
+ * PF_MCE_EARLY set.
* Don't use force here, it's convenient if the signal
* can be temporarily blocked.
* This could cause a loop when the user sets SIGBUS
@@ -275,7 +272,6 @@ static int kill_proc(struct to_kill *tk, unsigned long pfn, int flags)
*/
ret = send_sig_mceerr(BUS_MCEERR_AO, (void __user *)tk->addr,
addr_lsb, t); /* synchronous? */
- }
if (ret < 0)
pr_info("Memory failure: Error sending signal to %s:%d: %d\n",
t->comm, t->pid, ret);
--
2.23.0