The patch titled oom: prevent livelock when oom_kill_allocating_task is set has been added to the -mm tree. Its filename is oom-prevent-livelock-when-oom_kill_allocating_task-is-set.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: oom: prevent livelock when oom_kill_allocating_task is set From: David Rientjes <rientjes@xxxxxxxxxx> When /proc/sys/vm/oom_kill_allocating_task is set for large systems that want to avoid the lengthy tasklist scan, it's possible to livelock if current is ineligible for oom kill. This normally happens when it is set to OOM_DISABLE, but is also possible if any threads are sharing the same ->mm with a different tgid. So change __out_of_memory() to fall back to the full task-list scan if it was unable to kill `current'. Cc: Nick Piggin <npiggin@xxxxxxx> Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/oom_kill.c | 44 +++++++++++++++++++++----------------------- 1 file changed, 21 insertions(+), 23 deletions(-) diff -puN mm/oom_kill.c~oom-prevent-livelock-when-oom_kill_allocating_task-is-set mm/oom_kill.c --- a/mm/oom_kill.c~oom-prevent-livelock-when-oom_kill_allocating_task-is-set +++ a/mm/oom_kill.c @@ -514,34 +514,32 @@ void clear_zonelist_oom(struct zonelist */ static void __out_of_memory(gfp_t gfp_mask, int order) { - if (sysctl_oom_kill_allocating_task) { - oom_kill_process(current, gfp_mask, order, 0, NULL, - "Out of memory (oom_kill_allocating_task)"); - - } else { - unsigned long points; - struct task_struct *p; + struct task_struct *p; + unsigned long points; + if (sysctl_oom_kill_allocating_task) + if (!oom_kill_process(current, gfp_mask, order, 0, NULL, + "Out of memory (oom_kill_allocating_task)")) + return; retry: - /* - * Rambo mode: Shoot down a process and hope it solves whatever - * issues we may have. - */ - p = select_bad_process(&points, NULL); + /* + * Rambo mode: Shoot down a process and hope it solves whatever + * issues we may have. + */ + p = select_bad_process(&points, NULL); - if (PTR_ERR(p) == -1UL) - return; + if (PTR_ERR(p) == -1UL) + return; - /* Found nothing?!?! Either we hang forever, or we panic. */ - if (!p) { - read_unlock(&tasklist_lock); - panic("Out of memory and no killable processes...\n"); - } - - if (oom_kill_process(p, gfp_mask, order, points, NULL, - "Out of memory")) - goto retry; + /* Found nothing?!?! Either we hang forever, or we panic. */ + if (!p) { + read_unlock(&tasklist_lock); + panic("Out of memory and no killable processes...\n"); } + + if (oom_kill_process(p, gfp_mask, order, points, NULL, + "Out of memory")) + goto retry; } /* _ Patches currently in -mm which might be from rientjes@xxxxxxxxxx are memcg-fix-mem_cgroup_shrink_usage.patch mm-prevent-divide-error-for-small-values-of-vm_dirty_bytes.patch linux-next.patch oom-prevent-livelock-when-oom_kill_allocating_task-is-set.patch cpusets-restructure-the-function-cpuset_update_task_memory_state.patch cpusets-update-tasks-page-slab-spread-flags-in-time.patch cpusetmm-update-tasks-mems_allowed-in-time.patch cpusetmm-update-tasks-mems_allowed-in-time-fix.patch cpusetmm-update-tasks-mems_allowed-in-time-cleanup.patch page-allocator-use-a-pre-calculated-value-instead-of-num_online_nodes-in-fast-paths-do-not-override-definition-of-node_set_online-with-macro.patch memcg-add-file-based-rss-accounting.patch memcg-add-file-based-rss-accounting-fix-mem_cgroup_update_mapped_file_stat-oops.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html