Commit 49775047 authored by Miaohe Lin's avatar Miaohe Lin Committed by Linus Torvalds
Browse files

mm/memory-failure.c: rework the signaling logic in kill_proc 

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.

Link: https://lkml.kernel.org/r/20220218090118.1105-4-linmiaohe@huawei.com


Signed-off-by: default avatarMiaohe Lin <linmiaohe@huawei.com>
Acked-by: default avatarNaoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a994402b

mm/memory-failure.c

+6 −10
Original line number Diff line number Diff line
@@ -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)

	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. */

			ret = send_sig_mceerr(BUS_MCEERR_AO, (void __user *)tk->addr,

				addr_lsb, t);

	} 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);