| Message ID | 20170619172014.3377-2-manoj.iyer@canonical.com |
|---|---|
| State | New |
| Headers | show |
On Mon, Jun 19, 2017 at 12:20:14PM -0500, Manoj Iyer wrote: > From: Punit Agrawal <punit.agrawal@arm.com> > > On failing to migrate a page, soft_offline_huge_page() performs the > necessary update to the hugepage ref-count. > > But when !hugepage_migration_supported() , unmap_and_move_hugepage() > also decrements the page ref-count for the hugepage. The combined > behaviour leaves the ref-count in an inconsistent state. > > This leads to soft lockups when running the overcommitted hugepage test > from mce-tests suite. > > Soft offlining pfn 0x83ed600 at process virtual address 0x400000000000 > soft offline: 0x83ed600: migration failed 1, type 1fffc00000008008 (uptodate|head) > INFO: rcu_preempt detected stalls on CPUs/tasks: > Tasks blocked on level-0 rcu_node (CPUs 0-7): P2715 > (detected by 7, t=5254 jiffies, g=963, c=962, q=321) > thugetlb_overco R running task 0 2715 2685 0x00000008 > Call trace: > dump_backtrace+0x0/0x268 > show_stack+0x24/0x30 > sched_show_task+0x134/0x180 > rcu_print_detail_task_stall_rnp+0x54/0x7c > rcu_check_callbacks+0xa74/0xb08 > update_process_times+0x34/0x60 > tick_sched_handle.isra.7+0x38/0x70 > tick_sched_timer+0x4c/0x98 > __hrtimer_run_queues+0xc0/0x300 > hrtimer_interrupt+0xac/0x228 > arch_timer_handler_phys+0x3c/0x50 > handle_percpu_devid_irq+0x8c/0x290 > generic_handle_irq+0x34/0x50 > __handle_domain_irq+0x68/0xc0 > gic_handle_irq+0x5c/0xb0 > > Address this by changing the putback_active_hugepage() in > soft_offline_huge_page() to putback_movable_pages(). > > This only triggers on systems that enable memory failure handling > (ARCH_SUPPORTS_MEMORY_FAILURE) but not hugepage migration > (!ARCH_ENABLE_HUGEPAGE_MIGRATION). > > I imagine this wasn't triggered as there aren't many systems running > this configuration. > > BugLink: https://launchpad.net/bugs/1696165 > > [akpm@linux-foundation.org: remove dead comment, per Naoya] > Link: http://lkml.kernel.org/r/20170525135146.32011-1-punit.agrawal@arm.com > Reported-by: Manoj Iyer <manoj.iyer@canonical.com> > Tested-by: Manoj Iyer <manoj.iyer@canonical.com> > Suggested-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> > Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> > Cc: Wanpeng Li <wanpeng.li@hotmail.com> > Cc: Christoph Lameter <cl@linux.com> > Cc: Mel Gorman <mgorman@techsingularity.net> > Cc: <stable@vger.kernel.org> [3.14+] > Signed-off-by: Andrew Morton <akpm@linux-foundation.org> > Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> > > (backported from commit 30809f559a0d348c2dfd7ab05e9a451e2384962e) > Signed-off-by: Manoj Iyer <manoj.iyer@canonical.com> Acked-by: Seth Forshee <seth.forshee@canonical.com>
On 19/06/17 18:20, Manoj Iyer wrote: > From: Punit Agrawal <punit.agrawal@arm.com> > > On failing to migrate a page, soft_offline_huge_page() performs the > necessary update to the hugepage ref-count. > > But when !hugepage_migration_supported() , unmap_and_move_hugepage() > also decrements the page ref-count for the hugepage. The combined > behaviour leaves the ref-count in an inconsistent state. > > This leads to soft lockups when running the overcommitted hugepage test > from mce-tests suite. > > Soft offlining pfn 0x83ed600 at process virtual address 0x400000000000 > soft offline: 0x83ed600: migration failed 1, type 1fffc00000008008 (uptodate|head) > INFO: rcu_preempt detected stalls on CPUs/tasks: > Tasks blocked on level-0 rcu_node (CPUs 0-7): P2715 > (detected by 7, t=5254 jiffies, g=963, c=962, q=321) > thugetlb_overco R running task 0 2715 2685 0x00000008 > Call trace: > dump_backtrace+0x0/0x268 > show_stack+0x24/0x30 > sched_show_task+0x134/0x180 > rcu_print_detail_task_stall_rnp+0x54/0x7c > rcu_check_callbacks+0xa74/0xb08 > update_process_times+0x34/0x60 > tick_sched_handle.isra.7+0x38/0x70 > tick_sched_timer+0x4c/0x98 > __hrtimer_run_queues+0xc0/0x300 > hrtimer_interrupt+0xac/0x228 > arch_timer_handler_phys+0x3c/0x50 > handle_percpu_devid_irq+0x8c/0x290 > generic_handle_irq+0x34/0x50 > __handle_domain_irq+0x68/0xc0 > gic_handle_irq+0x5c/0xb0 > > Address this by changing the putback_active_hugepage() in > soft_offline_huge_page() to putback_movable_pages(). > > This only triggers on systems that enable memory failure handling > (ARCH_SUPPORTS_MEMORY_FAILURE) but not hugepage migration > (!ARCH_ENABLE_HUGEPAGE_MIGRATION). > > I imagine this wasn't triggered as there aren't many systems running > this configuration. > > BugLink: https://launchpad.net/bugs/1696165 > > [akpm@linux-foundation.org: remove dead comment, per Naoya] > Link: http://lkml.kernel.org/r/20170525135146.32011-1-punit.agrawal@arm.com > Reported-by: Manoj Iyer <manoj.iyer@canonical.com> > Tested-by: Manoj Iyer <manoj.iyer@canonical.com> > Suggested-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> > Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> > Cc: Wanpeng Li <wanpeng.li@hotmail.com> > Cc: Christoph Lameter <cl@linux.com> > Cc: Mel Gorman <mgorman@techsingularity.net> > Cc: <stable@vger.kernel.org> [3.14+] > Signed-off-by: Andrew Morton <akpm@linux-foundation.org> > Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> > > (backported from commit 30809f559a0d348c2dfd7ab05e9a451e2384962e) > Signed-off-by: Manoj Iyer <manoj.iyer@canonical.com> > --- > mm/memory-failure.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index f283c7e0a2a3..8c66042f0393 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1585,12 +1585,8 @@ static int soft_offline_huge_page(struct page *page, int flags) > if (ret) { > pr_info("soft offline: %#lx: migration failed %d, type %lx\n", > pfn, ret, page->flags); > - /* > - * We know that soft_offline_huge_page() tries to migrate > - * only one hugepage pointed to by hpage, so we need not > - * run through the pagelist here. > - */ > - putback_active_hugepage(hpage); > + if (!list_empty(&pagelist)) > + putback_movable_pages(&pagelist); > if (ret > 0) > ret = -EIO; > } else { > Looks OK to me, thanks Manoj Acked-by: Colin Ian King <colin.king@canonical.com> Acked-by: Colin Ian King <colin.king@canonical.com>
Applied to Zesty master-next. Thanks, -Stefan
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index f283c7e0a2a3..8c66042f0393 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1585,12 +1585,8 @@ static int soft_offline_huge_page(struct page *page, int flags) if (ret) { pr_info("soft offline: %#lx: migration failed %d, type %lx\n", pfn, ret, page->flags); - /* - * We know that soft_offline_huge_page() tries to migrate - * only one hugepage pointed to by hpage, so we need not - * run through the pagelist here. - */ - putback_active_hugepage(hpage); + if (!list_empty(&pagelist)) + putback_movable_pages(&pagelist); if (ret > 0) ret = -EIO; } else {