scheduling while atomic

This document (7008484) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 10 Service Pack 3

Situation

System is facing high performance issues, or does sometimes panic with similar call trace:

 scheduling while atomic: swapper/0x00000100/0

 Call Trace: <ffffffff802ef31d>{__sched_text_start+125}
<ffffffff8012fc07>{scheduler_tick+144}
<ffffffff80119ada>{smp_local_timer_interrupt+35}
<ffffffff8011a1bd>{smp_apic_timer_interrupt+65}
<ffffffff8010bb70>{apic_timer_interrupt+132}
<ffffffff802f12ee>{__down_write+138}
<ffffffff80200681>{find_next_bit+96}
<ffffffff801a49c5>{aio_free_ring+66} <ffffffff801a4ba3>{__put_ioctx+76}
<ffffffff801a4edf>{aio_complete+453}
<ffffffff801aad0d>{finished_one_bio+179}
<ffffffff801aadee>{dio_bio_complete+154}
<ffffffff801aaf27>{dio_bio_end_aio+30}
<ffffffff88230303>{:multipath:multipath_end_bh_io+30}
<ffffffff882308b8>{:multipath:multipath_end_request+229}
<ffffffff801efb02>{__end_that_request_first+646}
<ffffffff88006130>{:scsi_mod:scsi_delete_timer+18}
<ffffffff880072db>{:scsi_mod:scsi_end_request+110}
<ffffffff88007515>{:scsi_mod:scsi_io_completion+390}
<ffffffff8802e8e5>{:sd_mod:sd_rw_intr+544}
<ffffffff880077cc>{:scsi_mod:scsi_device_unbusy+103}
<ffffffff801f21cd>{blk_done_softirq+119}
<ffffffff8013a674>{__do_softirq+85}
<ffffffff8010c216>{call_softirq+30} <ffffffff8010d1a4>{do_softirq+44}
<ffffffff8010d56e>{do_IRQ+64} <ffffffff8010b352>{ret_from_intr+0}
<ffffffff880f4a16>{:processor:acpi_processor_idle+682}
<ffffffff880f476c>{:processor:acpi_processor_idle+0}
<ffffffff880f476c>{:processor:acpi_processor_idle+0}
<ffffffff80109e57>{cpu_idle+160}
<ffffffff80119917>{start_secondary+1330}

Resolution

This bug has been fixed and the patch is included since kernel 2.6.16.60-0.77.1.
To fix this issue, install the above kernel or a higher one.

Service Pack 4 also includes this patch.

Additional Information

Something went wrong below the IO completion handler (aio_complete). It is incorrect to perform ioctx freeing from aio_complete as it runs in atomic context.

Disclaimer

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