scsi: qla2xxx: Fix race between switch cmd completion and timeout

Fix race condition between switch cmd completion and timeout timer. Timer
has popped triggers command free. On IOCB completion, stale sp point was
reused. Instead, an abort will be sent to FW to nudge the command out of FW
where the normal completion will take place.

RIP: 0010:qla2x00_chk_ms_status+0xf3/0x1b0 [qla2xxx]
Call Trace:
<IRQ>
qla24xx_els_ct_entry.isra.15+0x1d4/0x2b0 [qla2xxx]
 qla24xx_msix_rsp_q+0x39/0xf0 [qla2xxx]
qla24xx_process_response_queue+0xbc/0x2b0 [qla2xxx]
qla24xx_msix_rsp_q+0x8a/0xf0 [qla2xxx]
__handle_irq_event_percpu+0xa0/0x1f0

Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 40bcf938cf4f03b5f746c59d3bd97bd8b6747b36..0fc563572fadcefe45d9942360c6a662ec4bb506 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -313,6 +313,7 @@ struct srb_cmd {
 #define SRB_CRC_CTX_DMA_VALID          BIT_2   /* DIF: context DMA valid */
 #define SRB_CRC_PROT_DMA_VALID         BIT_4   /* DIF: prot DMA valid */
 #define SRB_CRC_CTX_DSD_VALID          BIT_5   /* DIF: dsd_list valid */
+#define SRB_WAKEUP_ON_COMP             BIT_6
 
 /* To identify if a srb is of T10-CRC type. @sp => srb_t pointer */
 #define IS_PROT_IO(sp) (sp->flags & SRB_CRC_CTX_DSD_VALID)

diff --git a/drivers/scsi/qla2xxx/qla_gbl.h b/drivers/scsi/qla2xxx/qla_gbl.h
index 00fbd49a9a7ade75ba6e200df055ace18844ed08..6f2a37220a5581ce0d2c81a6c9b3f515d5f40cdc 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_gbl.h
+++ b/drivers/scsi/qla2xxx/qla_gbl.h
@@ -213,7 +213,7 @@ extern int qla24xx_post_upd_fcport_work(struct scsi_qla_host *, fc_port_t *);
 void qla2x00_handle_login_done_event(struct scsi_qla_host *, fc_port_t *,
        uint16_t *);
 int qla24xx_post_gnl_work(struct scsi_qla_host *, fc_port_t *);
-int qla24xx_async_abort_cmd(srb_t *);
+int qla24xx_async_abort_cmd(srb_t *, bool);
 int qla24xx_post_relogin_work(struct scsi_qla_host *vha);
 
 /*

diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 9d1a8b2c41a9b257007ce8c5fbc762b8b607e948..75538383de5b60bfd8e380087b1408cc2cc48d7a 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -50,16 +50,15 @@ qla2x00_sp_timeout(struct timer_list *t)
 {
        srb_t *sp = from_timer(sp, t, u.iocb_cmd.timer);
        struct srb_iocb *iocb;
-       scsi_qla_host_t *vha = sp->vha;
        struct req_que *req;
        unsigned long flags;
 
-       spin_lock_irqsave(&vha->hw->hardware_lock, flags);
-       req = vha->hw->req_q_map[0];
+       spin_lock_irqsave(sp->qpair->qp_lock_ptr, flags);
+       req = sp->qpair->req;
        req->outstanding_cmds[sp->handle] = NULL;
        iocb = &sp->u.iocb_cmd;
+       spin_unlock_irqrestore(sp->qpair->qp_lock_ptr, flags);
        iocb->timeout(sp);
-       spin_unlock_irqrestore(&vha->hw->hardware_lock, flags);
 }
 
 void
@@ -100,6 +99,8 @@ qla2x00_async_iocb_timeout(void *data)
        srb_t *sp = data;
        fc_port_t *fcport = sp->fcport;
        struct srb_iocb *lio = &sp->u.iocb_cmd;
+       int rc, h;
+       unsigned long flags;
 
        if (fcport) {
                ql_dbg(ql_dbg_disc, fcport->vha, 0x2071,
@@ -114,11 +115,26 @@ qla2x00_async_iocb_timeout(void *data)
 
        switch (sp->type) {
        case SRB_LOGIN_CMD:
-               /* Retry as needed. */
-               lio->u.logio.data[0] = MBS_COMMAND_ERROR;
-               lio->u.logio.data[1] = lio->u.logio.flags & SRB_LOGIN_RETRIED ?
-                       QLA_LOGIO_LOGIN_RETRIED : 0;
-               sp->done(sp, QLA_FUNCTION_TIMEOUT);
+               rc = qla24xx_async_abort_cmd(sp, false);
+               if (rc) {
+                       /* Retry as needed. */
+                       lio->u.logio.data[0] = MBS_COMMAND_ERROR;
+                       lio->u.logio.data[1] =
+                               lio->u.logio.flags & SRB_LOGIN_RETRIED ?
+                               QLA_LOGIO_LOGIN_RETRIED : 0;
+                       spin_lock_irqsave(sp->qpair->qp_lock_ptr, flags);
+                       for (h = 1; h < sp->qpair->req->num_outstanding_cmds;
+                           h++) {
+                               if (sp->qpair->req->outstanding_cmds[h] ==
+                                   sp) {
+                                       sp->qpair->req->outstanding_cmds[h] =
+                                           NULL;
+                                       break;
+                               }
+                       }
+                       spin_unlock_irqrestore(sp->qpair->qp_lock_ptr, flags);
+                       sp->done(sp, QLA_FUNCTION_TIMEOUT);
+               }
                break;
        case SRB_LOGOUT_CMD:
        case SRB_CT_PTHRU_CMD:
@@ -127,7 +143,21 @@ qla2x00_async_iocb_timeout(void *data)
        case SRB_NACK_PRLI:
        case SRB_NACK_LOGO:
        case SRB_CTRL_VP:
-               sp->done(sp, QLA_FUNCTION_TIMEOUT);
+               rc = qla24xx_async_abort_cmd(sp, false);
+               if (rc) {
+                       spin_lock_irqsave(sp->qpair->qp_lock_ptr, flags);
+                       for (h = 1; h < sp->qpair->req->num_outstanding_cmds;
+                           h++) {
+                               if (sp->qpair->req->outstanding_cmds[h] ==
+                                   sp) {
+                                       sp->qpair->req->outstanding_cmds[h] =
+                                           NULL;
+                                       break;
+                               }
+                       }
+                       spin_unlock_irqrestore(sp->qpair->qp_lock_ptr, flags);
+                       sp->done(sp, QLA_FUNCTION_TIMEOUT);
+               }
                break;
        }
 }
@@ -1594,7 +1624,7 @@ qla24xx_abort_iocb_timeout(void *data)
        struct srb_iocb *abt = &sp->u.iocb_cmd;
 
        abt->u.abt.comp_status = CS_TIMEOUT;
-       complete(&abt->u.abt.comp);
+       sp->done(sp, QLA_FUNCTION_TIMEOUT);
 }
 
 static void
@@ -1603,12 +1633,16 @@ qla24xx_abort_sp_done(void *ptr, int res)
        srb_t *sp = ptr;
        struct srb_iocb *abt = &sp->u.iocb_cmd;
 
-       if (del_timer(&sp->u.iocb_cmd.timer))
-               complete(&abt->u.abt.comp);
+       if (del_timer(&sp->u.iocb_cmd.timer)) {
+               if (sp->flags & SRB_WAKEUP_ON_COMP)
+                       complete(&abt->u.abt.comp);
+               else
+                       sp->free(sp);
+       }
 }
 
 int
-qla24xx_async_abort_cmd(srb_t *cmd_sp)
+qla24xx_async_abort_cmd(srb_t *cmd_sp, bool wait)
 {
        scsi_qla_host_t *vha = cmd_sp->vha;
        fc_port_t *fcport = cmd_sp->fcport;
@@ -1623,6 +1657,8 @@ qla24xx_async_abort_cmd(srb_t *cmd_sp)
        abt_iocb = &sp->u.iocb_cmd;
        sp->type = SRB_ABT_CMD;
        sp->name = "abort";
+       if (wait)
+               sp->flags = SRB_WAKEUP_ON_COMP;
 
        abt_iocb->timeout = qla24xx_abort_iocb_timeout;
        init_completion(&abt_iocb->u.abt.comp);
@@ -1646,10 +1682,11 @@ qla24xx_async_abort_cmd(srb_t *cmd_sp)
            "Abort command issued - hdl=%x, target_id=%x\n",
            cmd_sp->handle, fcport->tgt_id);
 
-       wait_for_completion(&abt_iocb->u.abt.comp);
-
-       rval = abt_iocb->u.abt.comp_status == CS_COMPLETE ?
-           QLA_SUCCESS : QLA_FUNCTION_FAILED;
+       if (wait) {
+               wait_for_completion(&abt_iocb->u.abt.comp);
+               rval = abt_iocb->u.abt.comp_status == CS_COMPLETE ?
+                       QLA_SUCCESS : QLA_FUNCTION_FAILED;
+       }
 
 done_free_sp:
        sp->free(sp);
@@ -1685,7 +1722,7 @@ qla24xx_async_abort_command(srb_t *sp)
                return qlafx00_fx_disc(vha, &vha->hw->mr.fcport,
                    FXDISC_ABORT_IOCTL);
 
-       return qla24xx_async_abort_cmd(sp);
+       return qla24xx_async_abort_cmd(sp, true);
 }
 
 static void