mm: invoke oom-killer from remaining unconverted page fault handlers (609838cf) · Commits · 戴 / test

A few remaining architectures directly kill the page faulting task in an out of memory situation. This is usually not a good idea since that task might not even use a significant amount of memory and so may not be the optimal victim to resolve the situation. Since 2.6.29's ("mm: invoke oom-killer from page fault") there is a hook that architecture page fault handlers are supposed to call to invoke the OOM killer and let it pick the right task to kill. Convert the remaining architectures over to this hook. To have the previous behavior of simply taking out the faulting task the vm.oom_kill_allocating_task sysctl can be set to 1. Signed-off-by:

Johannes Weiner <hannes@cmpxchg.org> Reviewed-by:

Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by:

David Rientjes <rientjes@google.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Cc: James Hogan <james.hogan@imgtec.com> Cc: David Howells <dhowells@redhat.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

arch/arc/mm/fault.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -207,8 +207,10 @@ out_of_memory:
		}
		up_read(&mm->mmap_sem);

		if (user_mode(regs))
		do_group_exit(SIGKILL); /* This will never return */
		if (user_mode(regs)) {
		pagefault_out_of_memory();
		return;
		}

		goto no_context;

arch/metag/mm/fault.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -224,8 +224,10 @@ do_sigbus:
		*/
		out_of_memory:
		up_read(&mm->mmap_sem);
		if (user_mode(regs))
		do_group_exit(SIGKILL);
		if (user_mode(regs)) {
		pagefault_out_of_memory();
		return 1;
		}

		no_context:
		/* Are we prepared to handle this kernel fault? */

arch/mn10300/mm/fault.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -345,9 +345,10 @@ no_context:
		*/
		out_of_memory:
		up_read(&mm->mmap_sem);
		printk(KERN_ALERT "VM: killing process %s\n", tsk->comm);
		if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR)
		do_exit(SIGKILL);
		if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR) {
		pagefault_out_of_memory();
		return;
		}
		goto no_context;

		do_sigbus:

arch/openrisc/mm/fault.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -267,10 +267,10 @@ out_of_memory:
		__asm__ __volatile__("l.nop 1");

		up_read(&mm->mmap_sem);
		printk("VM: killing process %s\n", tsk->comm);
		if (user_mode(regs))
		do_exit(SIGKILL);
		if (!user_mode(regs))
		goto no_context;
		pagefault_out_of_memory();
		return;

		do_sigbus:
		up_read(&mm->mmap_sem);

arch/score/mm/fault.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -172,10 +172,10 @@ out_of_memory:
		down_read(&mm->mmap_sem);
		goto survive;
		}
		printk("VM: killing process %s\n", tsk->comm);
		if (user_mode(regs))
		do_group_exit(SIGKILL);
		if (!user_mode(regs))
		goto no_context;
		pagefault_out_of_memory();
		return;

		do_sigbus:
		up_read(&mm->mmap_sem);

Admin message