Just to chip in with my experience of this bug. I have two physically identical machines (HP DL160 G5s) each running a few kvm instances. One of them experiences this bug repeatedly (daily, usually), the other one never. It's really annoying me.
Linux version 2.6.26-2-amd64 (Debian 2.6.26-19) (da...@debian.org) (gcc version 4.1.3 20080704 (prerelease) (Debian 4.1.2-25)) #1 SMP Wed Aug 19 22:33:18 UTC 20 09 INFO: task kvm:4559 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kvm D 0000000000000082 0 4559 1 ffff8101c6c9bc58 0000000000000082 ffff81021c002210 ffffffff8031b528 ffff81021c8ef7b0 ffff81021d1f0ad0 ffff81021c8efa38 00000003a0083c0d 0000000000000086 ffffffff802125eb 00003042a87d1d5c ffffffff8024acb6 Call Trace: [<ffffffff8031b528>] kobject_get+0x12/0x17 [<ffffffff802125eb>] read_tsc+0x9/0x20 [<ffffffff8024acb6>] getnstimeofday+0x39/0x98 [<ffffffff80272934>] sync_page_killable+0x0/0x31 [<ffffffff80429087>] io_schedule+0x5c/0x9e [<ffffffff80271116>] sync_page+0x3c/0x41 [<ffffffff8027293d>] sync_page_killable+0x9/0x31 [<ffffffff804291fa>] __wait_on_bit_lock+0x36/0x66 [<ffffffff80271063>] __lock_page_killable+0x5e/0x64 [<ffffffff8024624f>] wake_bit_function+0x0/0x23 [<ffffffff80272c5f>] generic_file_aio_read+0x2fa/0x4ae [<ffffffff8029ae47>] do_sync_read+0xc9/0x10c [<ffffffff80246221>] autoremove_wake_function+0x0/0x2e [<ffffffff802125eb>] read_tsc+0x9/0x20 [<ffffffff80248dc2>] ktime_get_ts+0x22/0x4b [<ffffffff8029b638>] vfs_read+0xaa/0x152 [<ffffffff8029bb00>] sys_pread64+0x50/0x70 [<ffffffff8020beca>] system_call_after_swapgs+0x8a/0x8f I can supply a load more stack traces if you like, not all of them from kvm. I notice that the one thing they have in common is that read_tsc+0x9 is on the stack, sometimes at the top and sometimes (as in this example) appearing twice. This seems implausible to me from reading the code (http://lxr.linux.no/#linux+v2.6.26/arch/x86/kernel/tsc_64.c#L306) so the only options I can think of is that either pv_cpu_ops has become corrupt or the code that generates stack traces has made a mistake. Are either of these options likely? I really want to get this fixed because a machine that crashes daily is useless. So far I've tried flashing the BIOS on the machine and altering the loading pattern (e.g. number of CPUs allocated to each VM), but I haven't yet tried any of the kernel patches mentioned or installing a new one from backports. Are they worth a go? Richard. - -------------------------------------------------------------------------------- IMPORTANT The information contained in this e-mail and any attachments is intended only for the named recipient and may be privileged or confidential. If you are not the intended recipient, please notify us immediately on +44 (0)1908 425000 and do not disclose, copy, distribute or take any action based on the contents of this e-mail. You should understand and accept that, when communicating with us by e-mail, it is not a totally secure communication medium. We accept no liability for any direct, indirect or consequential loss arising from any action taken in reliance on the information contained in this e-mail and give no warranty or representation as to its accuracy or reliability. DIGITALK has the facility to monitor and read both incoming and outgoing communications by e-mail. In line with industry efforts to reduce the proliferation of un-solicited SPAM, DIGITALK uses methods and ban-lists to prevent malicious content reaching our users. This message and any attachments has been scanned for known viruses. However, we would advise you to ensure the content is indeed virus free. We do not, to the extent permitted by law, accept any liability (whether in contract, negligence or otherwise) for any virus infection and/or external compromise of security and/or breach of confidentiality in relation to transmissions sent by e-mail. VAT No: GB 876 3287 81. Reg No: 3080801 Place of Registration: England Registered Office Address: 2 Radian Court, Knowlhill, Milton Keynes - -------------------------------------------------------------------------------- -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
