Hello, I am testing ATA device durability during hot unplug. I have a power fault test suite that has turned up issues with the fsync->SCSI->ATA codepath. If a device is unplugged while an fsync is in progress, ATA returns a flush error to the SCSI driver but scsi_io_completion() seems to disregard it. fsync() returns no error, which should mean that the write was durably flushed to disk. I expect fsync() to return EIO or something similar when the flush isn't acked by the device.
When the failure occurs, the SCSI sense key is set to ABORTED_COMMAND. However, scsi_end_command() is called without any of the sense context and scsi_io_completion() returns early without checking sense at all. This commit may be related: d6b0c53723753fc0cfda63f56735b225c43e1e9a (http://git.opencores.org/?a=commitdiff&p=linux&h=d6b0c53723753fc0cfda63f56735b225c43e1e9a) The following patch fixes the issue, but it's a hack. I only have a vague understanding of Linux drivers, so I'm looking for advice on how to make this fix better and get it upstream. Thanks! Steven Haber Qumulo, Inc. diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 9db097a..789af39 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -822,40 +822,44 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) /* * Recovered errors need reporting, but they're always treated * as success, so fiddle the result code here. For BLOCK_PC * we already took a copy of the original into rq->errors which * is what gets returned to the user */ if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) { /* if ATA PASS-THROUGH INFORMATION AVAILABLE skip * print since caller wants ATA registers. Only occurs on * SCSI ATA PASS_THROUGH commands when CK_COND=1 */ if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d)) ; else if (!(req->cmd_flags & REQ_QUIET)) scsi_print_sense("", cmd); result = 0; /* BLOCK_PC may have set error */ error = 0; } + if (sense_valid && (sshdr.sense_key == ABORTED_COMMAND) && + good_bytes == 0) + error = (sshdr.asc == 0x10) ? -EILSEQ : -EIO; + /* * A number of bytes were successfully read. If there * are leftovers and there is some kind of error * (result != 0), retry the rest. */ if (scsi_end_request(cmd, error, good_bytes, result == 0) == NULL) return; error = __scsi_error_from_host_byte(cmd, result); if (host_byte(result) == DID_RESET) { /* Third party bus reset or reset for error recovery * reasons. Just retry the command and see what * happens. */ action = ACTION_RETRY; } else if (sense_valid && !sense_deferred) { switch (sshdr.sense_key) { case UNIT_ATTENTION: if (cmd->device->removable) { -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
