On Tue, May 31, 2016 at 8:21 PM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > On Tue, May 31, 2016 at 1:38 AM, Wei Fang <fangwei1@xxxxxxxxxx> wrote: >> sas_ata_strategy_handler() adds the works of the ata error handler >> to system_unbound_wq. This workqueue asynchronously runs work items, >> so the ata error handler will be performed concurrently on different >> CPUs. In this case, ->host_failed will be decreased simultaneously in >> scsi_eh_finish_cmd() on different CPUs, and become abnormal. >> >> It will lead to permanently inequal between ->host_failed and >> ->host_busy, and scsi error handler thread won't become running. >> IO errors after that won't be handled forever. >> >> Use atomic type for ->host_failed to fix this race. >> >> This fixes the problem introduced in >> commit 50824d6c5657 ("[SCSI] libsas: async ata-eh"). >> >> Reviewed-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> >> Signed-off-by: Wei Fang <fangwei1@xxxxxxxxxx> > > Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx> Should also tag this for -stable. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html