path: root/drivers/scsi/libata-core.c
diff options
authorAlbert Lee <albertcc@tw.ibm.com>2005-04-29 17:34:59 +0800
committerJeff Garzik <jgarzik@pobox.com>2005-05-15 18:46:59 -0400
commit21b1ed74ee3667dcabcba92e486988ea9119a085 (patch)
treef4cf281ecf24a3352aebd1231cac6002fd44d82d /drivers/scsi/libata-core.c
parentf85bdb9ce9e130ce00f7a91523931fdd8f96f102 (diff)
[PATCH] libata: Prevent the interrupt handler from completing a command twice
Problem: During the libata CD-ROM stress test, sometimes the "BUG: timeout without command" error is seen. Root cause: Unexpected interrupt occurs after the ata_qc_complete() is called, but before the SCSI error handler. The interrupt handler is invoked before the SCSI error handler, and it clears the command by calling ata_qc_complete() again. Later when the SCSI error handler is run, the ata_queued_cmd is already gone, causing the "BUG: timeout without command" error. Changes: - Use the ATA_QCFLAG_ACTIVE flag to prevent the interrupt handler from completing the command twice, before the scsi_error_handler. Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Diffstat (limited to 'drivers/scsi/libata-core.c')
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 0b5d3a5b7eda..f70935cba173 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -2539,7 +2539,7 @@ static void atapi_request_sense(struct ata_port *ap, struct ata_device *dev,
ata_sg_init_one(qc, cmd->sense_buffer, sizeof(cmd->sense_buffer));
qc->dma_dir = DMA_FROM_DEVICE;
- memset(&qc->cdb, 0, sizeof(ap->cdb_len));
+ memset(&qc->cdb, 0, ap->cdb_len);
qc->cdb[0] = REQUEST_SENSE;
@@ -2811,6 +2811,7 @@ void ata_qc_complete(struct ata_queued_cmd *qc, u8 drv_stat)
/* call completion callback */
rc = qc->complete_fn(qc, drv_stat);
+ qc->flags &= ~ATA_QCFLAG_ACTIVE;
/* if callback indicates not to complete command (non-zero),
* return immediately
@@ -3229,7 +3230,8 @@ irqreturn_t ata_interrupt (int irq, void *dev_instance, struct pt_regs *regs)
struct ata_queued_cmd *qc;
qc = ata_qc_from_tag(ap, ap->active_tag);
- if (qc && (!(qc->tf.ctl & ATA_NIEN)))
+ if (qc && (!(qc->tf.ctl & ATA_NIEN)) &&
+ (qc->flags & ATA_QCFLAG_ACTIVE))
handled |= ata_host_intr(ap, qc);

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