----- Original Message ----- > Hi Qian, > > On Wed, Jan 26, 2011 at 03:45:55AM -0500, CAI Qian wrote: > > Andrea, > > > > khugepaged hung during swapping there. > > > > INFO: task khugepaged:276 blocked for more than 120 seconds. > > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this > > message. > > khugepaged D ffff880fa0fd4610 0 276 2 0x00000000 > > ffff880fa07cfcc0 0000000000000046 ffff88201ffdac00 0000000000000000 > > 0000000000014d40 ffff880fa0fd4080 ffff880fa0fd4610 ffff880fa07cffd8 > > ffff880fa0fd4618 0000000000014d40 ffff880fa07ce010 0000000000014d40 > > Call Trace: > > [<ffffffff814afeb5>] rwsem_down_failed_common+0xb5/0x140 > > [<ffffffff814aff53>] rwsem_down_write_failed+0x13/0x20 > > [<ffffffff812301a3>] call_rwsem_down_write_failed+0x13/0x20 > > [<ffffffff814af4d2>] ? down_write+0x32/0x40 > > [<ffffffff81146b4d>] khugepaged+0x8ad/0x1300 > > [<ffffffff8100a6f0>] ? __switch_to+0xd0/0x320 > > [<ffffffff811462a0>] ? khugepaged+0x0/0x1300 > > [<ffffffff810830f0>] ? autoremove_wake_function+0x0/0x40 > > [<ffffffff811462a0>] ? khugepaged+0x0/0x1300 > > [<ffffffff81082a56>] kthread+0x96/0xa0 > > [<ffffffff8100cdc4>] kernel_thread_helper+0x4/0x10 > > [<ffffffff810829c0>] ? kthread+0x0/0xa0 > > [<ffffffff8100cdc0>] ? kernel_thread_helper+0x0/0x10 > > INFO: task pgrep:6039 blocked for more than 120 seconds. > > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this > > message. > > pgrep D ffff887f606f1ab0 0 6039 6038 0x00000080 > > ffff8821e39c1ce0 0000000000000082 0000000000000246 0000000000000000 > > 0000000000014d40 ffff887f606f1520 ffff887f606f1ab0 ffff8821e39c1fd8 > > ffff887f606f1ab8 0000000000014d40 ffff8821e39c0010 0000000000014d40 > > Call Trace: > > [<ffffffff814afeb5>] rwsem_down_failed_common+0xb5/0x140 > > [<ffffffff814aff75>] rwsem_down_read_failed+0x15/0x17 > > [<ffffffff81230174>] call_rwsem_down_read_failed+0x14/0x30 > > [<ffffffff814af504>] ? down_read+0x24/0x30 > > [<ffffffff8111f4dc>] access_process_vm+0x4c/0x200 > > [<ffffffff8113f3fe>] ? fallback_alloc+0x14e/0x270 > > [<ffffffff811afa4d>] proc_pid_cmdline+0x6d/0x120 > > [<ffffffff81137eba>] ? alloc_pages_current+0x9a/0x100 > > [<ffffffff811b037d>] proc_info_read+0xad/0xf0 > > [<ffffffff81154315>] vfs_read+0xc5/0x190 > > [<ffffffff811544e1>] sys_read+0x51/0x90 > > [<ffffffff8100bf82>] system_call_fastpath+0x16/0x1b > > pgrep hung too, it's not just khugepaged hanging and it's not obvious > for now that khugepaged was guilty of forgetting an unlock, could be > the process deadlocked somewhere with the mmap_sem hold. Can you press > SYSRQ+T? Hopefully that will show the holder. Also is CONFIG_NUMA=y/n? Unfortunately, SYSRQ+T was not working. CONFIG_NUMA=y and this is an NUMA system as well. CAI Qian -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>