Message ID | 20210225214237.22400-1-tyreld@linux.ibm.com |
---|---|
Headers | show |
Series | ibmvfc: hard reset fixes | expand |
On 2/25/21 1:42 PM, Tyrel Datwyler wrote: > A hard reset results in a complete transport disconnect such that the > CRQ connection with the partner VIOS is broken. This has the side effect > of also invalidating the associated sub-CRQs. The current code assumes > that the sub-CRQs are perserved resulting in a protocol violation after > trying to reconnect them with the VIOS. This introduces an infinite loop > such that the VIOS forces a disconnect after each subsequent attempt to > re-register with invalid handles. > > Avoid the aforementioned issue by releasing the sub-CRQs prior to CRQ > disconnect, and driving a reinitialization of the sub-CRQs once a new > CRQ is registered with the hypervisor. > > fixes: faacf8c5f1d5 ("ibmvfc: add alloc/dealloc routines for SCSI Sub-CRQ Channels") > Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com> > Reviewed-by: Brian King <brking@linux.ibm.com> > --- > drivers/scsi/ibmvscsi/ibmvfc.c | 21 +++++++++------------ > 1 file changed, 9 insertions(+), 12 deletions(-) > > diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c > index 384960036f8b..2cca55f2e464 100644 > --- a/drivers/scsi/ibmvscsi/ibmvfc.c > +++ b/drivers/scsi/ibmvscsi/ibmvfc.c > @@ -158,6 +158,9 @@ static void ibmvfc_npiv_logout(struct ibmvfc_host *); > static void ibmvfc_tgt_implicit_logout_and_del(struct ibmvfc_target *); > static void ibmvfc_tgt_move_login(struct ibmvfc_target *); > > +static void ibmvfc_release_sub_crqs(struct ibmvfc_host *); > +static void ibmvfc_init_sub_crqs(struct ibmvfc_host *); > + > static const char *unknown_error = "unknown error"; > > static long h_reg_sub_crq(unsigned long unit_address, unsigned long ioba, > @@ -926,8 +929,8 @@ static int ibmvfc_reset_crq(struct ibmvfc_host *vhost) > unsigned long flags; > struct vio_dev *vdev = to_vio_dev(vhost->dev); > struct ibmvfc_queue *crq = &vhost->crq; > - struct ibmvfc_queue *scrq; > - int i; > + > + ibmvfc_release_sub_crqs(vhost); > > /* Close the CRQ */ > do { > @@ -936,6 +939,8 @@ static int ibmvfc_reset_crq(struct ibmvfc_host *vhost) > rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address); > } while (rc == H_BUSY || H_IS_LONG_BUSY(rc)); > > + ibmvfc_init_sub_crqs(vhost); This has the same issue as patch 5 in that if fail to set up sub-crqs do_enquiry will be set to zero, but the locked code region below will then flip it back to one which we don't want. -T > + > spin_lock_irqsave(vhost->host->host_lock, flags); > spin_lock(vhost->crq.q_lock); > vhost->state = IBMVFC_NO_CRQ; > @@ -947,16 +952,6 @@ static int ibmvfc_reset_crq(struct ibmvfc_host *vhost) > memset(crq->msgs.crq, 0, PAGE_SIZE); > crq->cur = 0; > > - if (vhost->scsi_scrqs.scrqs) { > - for (i = 0; i < nr_scsi_hw_queues; i++) { > - scrq = &vhost->scsi_scrqs.scrqs[i]; > - spin_lock(scrq->q_lock); > - memset(scrq->msgs.scrq, 0, PAGE_SIZE); > - scrq->cur = 0; > - spin_unlock(scrq->q_lock); > - } > - } > - > /* And re-open it again */ > rc = plpar_hcall_norets(H_REG_CRQ, vdev->unit_address, > crq->msg_token, PAGE_SIZE); > @@ -966,6 +961,7 @@ static int ibmvfc_reset_crq(struct ibmvfc_host *vhost) > dev_warn(vhost->dev, "Partner adapter not ready\n"); > else if (rc != 0) > dev_warn(vhost->dev, "Couldn't register crq (rc=%d)\n", rc); > + > spin_unlock(vhost->crq.q_lock); > spin_unlock_irqrestore(vhost->host->host_lock, flags); > > @@ -5692,6 +5688,7 @@ static void ibmvfc_deregister_scsi_channel(struct ibmvfc_host *vhost, int index) > > free_irq(scrq->irq, scrq); > irq_dispose_mapping(scrq->irq); > + scrq->irq = 0; > > do { > rc = plpar_hcall_norets(H_FREE_SUB_CRQ, vdev->unit_address, >