From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: [PATCH v2 02/15] IB/srp: Fix race between srp_queuecommand() and srp_claim_req() Date: Fri, 28 Jun 2013 14:48:04 +0200 Message-ID: <51CD8604.5010801@acm.org> References: <51CD856A.3010102@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <51CD856A.3010102-HInyCGIudOg@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Roland Dreier Cc: David Dillow , Vu Pham , Sebastian Riemer , linux-rdma List-Id: linux-rdma@vger.kernel.org Avoid that srp_claim_command() can claim a command while srp_queuecommand() is still busy queueing the same command. Found this via source reading. Signed-off-by: Bart Van Assche Cc: Roland Dreier Cc: David Dillow Cc: Vu Pham Cc: Sebastian Riemer --- drivers/infiniband/ulp/srp/ib_srp.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index 368d160..035167b 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -1047,13 +1047,11 @@ map_complete: static void srp_put_tx_iu(struct srp_target_port *target, struct srp_iu *iu, enum srp_iu_type iu_type) { - unsigned long flags; + lockdep_assert_held(&target->lock); - spin_lock_irqsave(&target->lock, flags); list_add(&iu->list, &target->free_tx); if (iu_type != SRP_IU_RSP) ++target->req_lim; - spin_unlock_irqrestore(&target->lock, flags); } /* @@ -1210,7 +1208,10 @@ static int srp_response_common(struct srp_target_port *target, s32 req_delta, if (err) { shost_printk(KERN_ERR, target->scsi_host, PFX "unable to post response: %d\n", err); + + spin_lock_irqsave(&target->lock, flags); srp_put_tx_iu(target, iu, SRP_IU_RSP); + spin_unlock_irqrestore(&target->lock, flags); } return err; @@ -1367,7 +1368,6 @@ static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd) req = list_first_entry(&target->free_reqs, struct srp_request, list); list_del(&req->list); - spin_unlock_irqrestore(&target->lock, flags); dev = target->srp_host->srp_dev->dev; ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len, @@ -1401,6 +1401,7 @@ static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd) shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n"); goto err_unmap; } + spin_unlock_irqrestore(&target->lock, flags); return 0; @@ -1409,8 +1410,6 @@ err_unmap: err_iu: srp_put_tx_iu(target, iu, SRP_IU_CMD); - - spin_lock_irqsave(&target->lock, flags); list_add(&req->list, &target->free_reqs); err_unlock: @@ -1729,7 +1728,10 @@ static int srp_send_tsk_mgmt(struct srp_target_port *target, ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt, DMA_TO_DEVICE); if (srp_post_send(target, iu, sizeof *tsk_mgmt)) { + spin_lock_irq(&target->lock); srp_put_tx_iu(target, iu, SRP_IU_TSK_MGMT); + spin_unlock_irq(&target->lock); + return -1; } -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html