On Mon, Aug 21, 2017 at 02:36:40PM +0200, Rafael J. Wysocki wrote: > On Monday, August 21, 2017 9:48:17 AM CEST Chen Yu wrote: > > On Mon, Aug 21, 2017 at 08:47:09AM +0200, Michal Hocko wrote: > > > On Sat 19-08-17 18:21:26, Chen Yu wrote: > > > > There is a problem that when counting the pages for creating > > > > the hibernation snapshot will take significant amount of > > > > time, especially on system with large memory. Since the counting > > > > job is performed with irq disabled, this might lead to NMI lockup. > > > > The following warning were found on a system with 1.5TB DRAM: > > > > > > > > [ 1124.758184] Freezing user space processes ... (elapsed 0.002 seconds) done. > > > > [ 1124.768721] OOM killer disabled. > > > > [ 1124.847009] PM: Preallocating image memory... > > > > [ 1139.392042] NMI watchdog: Watchdog detected hard LOCKUP on cpu 27 > > > > [ 1139.392076] CPU: 27 PID: 3128 Comm: systemd-sleep Not tainted 4.13.0-0.rc2.git0.1.fc27.x86_64 #1 > > > > [ 1139.392077] task: ffff9f01971ac000 task.stack: ffffb1a3f325c000 > > > > [ 1139.392083] RIP: 0010:memory_bm_find_bit+0xf4/0x100 > > > > [ 1139.392084] RSP: 0018:ffffb1a3f325fc20 EFLAGS: 00000006 > > > > [ 1139.392084] RAX: 0000000000000000 RBX: 0000000013b83000 RCX: ffff9fbe89caf000 > > > > [ 1139.392085] RDX: ffffb1a3f325fc30 RSI: 0000000000003200 RDI: ffff9fbeaffffe80 > > > > [ 1139.392085] RBP: ffffb1a3f325fc40 R08: 0000000013b80000 R09: ffff9fbe89c54878 > > > > [ 1139.392085] R10: ffffb1a3f325fc2c R11: 0000000013b83200 R12: 0000000000000400 > > > > [ 1139.392086] R13: fffffd552e0c0000 R14: ffff9fc1bffd31e0 R15: 0000000000000202 > > > > [ 1139.392086] FS: 00007f3189704180(0000) GS:ffff9fbec8ec0000(0000) knlGS:0000000000000000 > > > > [ 1139.392087] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > > [ 1139.392087] CR2: 00000085da0f7398 CR3: 000001771cf9a000 CR4: 00000000007406e0 > > > > [ 1139.392088] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > > > [ 1139.392088] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > > [ 1139.392088] PKRU: 55555554 > > > > [ 1139.392089] Call Trace: > > > > [ 1139.392092] ? memory_bm_set_bit+0x29/0x60 > > > > [ 1139.392094] swsusp_set_page_free+0x2b/0x30 > > > > [ 1139.392098] mark_free_pages+0x147/0x1c0 > > > > [ 1139.392099] count_data_pages+0x41/0xa0 > > > > [ 1139.392101] hibernate_preallocate_memory+0x80/0x450 > > > > [ 1139.392102] hibernation_snapshot+0x58/0x410 > > > > [ 1139.392103] hibernate+0x17c/0x310 > > > > [ 1139.392104] state_store+0xdf/0xf0 > > > > [ 1139.392107] kobj_attr_store+0xf/0x20 > > > > [ 1139.392111] sysfs_kf_write+0x37/0x40 > > > > [ 1139.392113] kernfs_fop_write+0x11c/0x1a0 > > > > [ 1139.392117] __vfs_write+0x37/0x170 > > > > [ 1139.392121] ? handle_mm_fault+0xd8/0x230 > > > > [ 1139.392122] vfs_write+0xb1/0x1a0 > > > > [ 1139.392123] SyS_write+0x55/0xc0 > > > > [ 1139.392126] entry_SYSCALL_64_fastpath+0x1a/0xa5 > > > > ... > > > > [ 1144.690405] done (allocated 6590003 pages) > > > > [ 1144.694971] PM: Allocated 26360012 kbytes in 19.89 seconds (1325.28 MB/s) > > > > > > > > It has taken nearly 20 seconds(2.10GHz CPU) thus the NMI lockup > > > > was triggered. In case the timeout of the NMI watch dog has been > > > > set to 1 second, a safe interval should be 6590003/20 = 320k pages > > > > in theory. However there might also be some platforms running at a > > > > lower frequency, so feed the watchdog every 100k pages. > > > > > > > > Reported-by: Jan Filipcewicz <jan.filipcewicz@xxxxxxxxx> > > > > Suggested-by: Michal Hocko <mhocko@xxxxxxxxxx> > > > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > > > Cc: Michal Hocko <mhocko@xxxxxxxxxx> > > > > Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> > > > > Cc: Vlastimil Babka <vbabka@xxxxxxx> > > > > Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> > > > > Cc: Len Brown <lenb@xxxxxxxxxx> > > > > Cc: Dan Williams <dan.j.williams@xxxxxxxxx> > > > > Cc: linux-kernel@xxxxxxxxxxxxxxx > > > > Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx> > > > > > > OK, this looks better. Feel free to add > > > Reviewed-by: Michal Hocko <mhocko@xxxxxxxx> > > > > > Thanks! > > OK, so can you please resend the patch with a CC to linux-pm and > the Reviewed-by from Michal? > OK, will do. Thanks, Yu > Thanks, > Rafael > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
