On Wed, Mar 27, 2013 at 12:55:41PM +1100, Robert Norris wrote: > The console shows a new "BUG: soft lockup" line every few seconds
Looking closer, the whole thing starts with a _hard_ lockup. 2013-03-26T08:33:39.921834-04:00 imap30 kernel: [185090.090328] Watchdog detected hard LOCKUP on cpu 3 (also in the logs of the other two servers I mentioned). Looking down to where the watchdog interrupt comes in: 2013-03-26T08:33:39.921870-04:00 imap30 kernel: [185090.090426] <<EOE>> <IRQ> [<ffffffff8112a5b1>] ? end_buffer_async_read+0x79/0xff Disassembling: 0xffffffff8112a57a <+66>: mov %rbx,%rdi 0xffffffff8112a57d <+69>: callq 0xffffffff81129265 <buffer_io_error> 0xffffffff8112a582 <+74>: lock orb $0x2,0x0(%rbp) 0xffffffff8112a587 <+79>: mov 0x0(%rbp),%rax 0xffffffff8112a58b <+83>: test $0x8,%ah 0xffffffff8112a58e <+86>: jne 0xffffffff8112a594 <end_buffer_async_read+92> 0xffffffff8112a590 <+88>: ud2 0xffffffff8112a592 <+90>: jmp 0xffffffff8112a592 <end_buffer_async_read+90> That lock at +74 is presumably the offender here. Which is line 275 of fs/buffer.c: 275 SetPageError(page); So another CPU has these page flags locked right now, and isn't keen to release that lock? I don't know how to debug this further. What's the next step? Thanks, Rob. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
