On Thu 22-11-12 12:58:24, George Spelvin wrote: > I'm having an interesting issue with a uniprocessor Pentium 4 machine > locking up overnight. 3.6.5 didn't do that, but 3.7-rc6 is not doing > so well. I've added some CCs which are hopefully relevant. Specifially I remember Mel fixing some -mm lockup recently although after googling for a while that is likely something different. > It's kind of a funny lockup. Some things work: > > - TCP SYN handshake > - Alt-SysRq > > And others don't: > > - Caps lock > - Shift-PgUp > - Alt-Fn > - Screen unblanking > - Actually talking to a daemon > > This is a "headless" machine that boots to a text console and has zero > console activity until the lockup. > > This has happened overnight, three nights in a row. I had to turn screen > blanking off to see anything on the screen. Running the daily cron jobs > manually just now didn't trigger it, so I haven't found a proximate cause. > > The *first* error has scrolled off the screen, but what I can see > an infinite stream (at about 20s intervals) of: > > BUG: soft lockup - CPU#0 stuck for 22s! [kswapd0:317] > Pid: 317, comm: kswapd0 Not tainted 3.7.0-RC6 #224 HP Pavilion 04 P6319A-ABA 750N/P4B266LA > EIP: 0060:[<c10571f7>] EFLAGS: 00000202 CPU: 0 > EIP is at __zone_watermark_ok+0x5f/7e, 0x67/7e, 0x6e/0x7e, or 0x74/7e > (Didn't type registers & stack) > Call Trace: > [<c105774f>] ? zone_watermark_ok_safe+0x34/0x3a > [<c105ec7e>] ? kswapd+0x2fa/0x6f6 > [<c105e984>] ? try_to_free_pages+0x4b8/0x4b8 > [<c103106b>] ? kthread+0x67/0x6c > [<c12559b7>] ? ret_from_kernel_thread+0x1b/0x28 > [<c1031004>] ? -_kthread_parkme+0x4c.0x4c > Code: (didn't type in first line) > 5f 67 6e 74 7e > c9 39 d6 7f 14 eb 1c 6b c1 2c <8b> 44 05 60 d3 e0 29 c6 <d1> fb 39 de 7e 09 41 <39> f9 7c ea b0 01 <eb> 02 31 c0 5a 5b 5e 5f 5d c3 01 14 85 7c 16 Taking picture of the screen with a digital camera can usually save you some typing :) > The lack of scrollback limits me to 49 lines of SysRq output, and usually the most interesting > part disappears off the screen. Two things I can see: > > - SysRq-W shows no blocked tasks > - SysRq-M shows zero swap in use, and apparently adequate free memory > DMA: <various segments> = 9048kB > Normal: <various> = 116312kB > HighMem: <various> = 41660kB > 416557 total pagecache pages > 0 pages in swap cache > Swap cache stats: add 0, delete 0, find 0/0 > Free swap = 4883724kB > Total swap = 4883724kB > 524260 pages RAM > 296958 pages HighMem > 5221 pages reserved > 406417 pages shared > 351419 pages non-shared > > Does anyone have any debugging suggestions? Waiting overnight to > make a good/bad decision makes bisecting pretty slow... Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- 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>