diff options
author | Hiral Shah <hishah@cisco.com> | 2014-11-10 12:54:36 -0800 |
---|---|---|
committer | Christoph Hellwig <hch@lst.de> | 2014-11-20 09:11:00 +0100 |
commit | 41df7b02db82cf6c14f094757bac3830d10a827f (patch) | |
tree | 4d32c8ce1aa9fe73dc269129a4a4c3b5626e90f0 | |
parent | 0ee7b8714dca511a68826a300cc4966f2e83a6c3 (diff) |
Fnic: Fnic Driver crashed with NULL pointer reference
When issuing I/O request, if the I/O completes before returning from
fnic_queuecommand(), we may be referencing scsi_cmnd structure that may
be freed by interrupt handler. Acquring IO lock would synchronize
fnic_queuecommand and interrupt handler.
- Increment fnic version from 1.6.0.15 to 1.6.0.16
Signed-off-by: Hiral Shah <hishah@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
Signed-off-by: Anil Chintalapati <achintal@cisco.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
-rw-r--r-- | drivers/scsi/fnic/fnic.h | 2 | ||||
-rw-r--r-- | drivers/scsi/fnic/fnic_scsi.c | 21 |
2 files changed, 19 insertions, 4 deletions
diff --git a/drivers/scsi/fnic/fnic.h b/drivers/scsi/fnic/fnic.h index 977960b03c9f..3b73b96619e2 100644 --- a/drivers/scsi/fnic/fnic.h +++ b/drivers/scsi/fnic/fnic.h @@ -39,7 +39,7 @@ #define DRV_NAME "fnic" #define DRV_DESCRIPTION "Cisco FCoE HBA Driver" -#define DRV_VERSION "1.6.0.15" +#define DRV_VERSION "1.6.0.16" #define PFX DRV_NAME ": " #define DFX DRV_NAME "%d: " diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c index 29d23a3c0686..2097de42a147 100644 --- a/drivers/scsi/fnic/fnic_scsi.c +++ b/drivers/scsi/fnic/fnic_scsi.c @@ -421,9 +421,10 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_ int ret; u64 cmd_trace; int sg_count = 0; - unsigned long flags; + unsigned long flags = 0; unsigned long ptr; struct fc_rport_priv *rdata; + spinlock_t *io_lock = NULL; if (unlikely(fnic_chk_state_flags_locked(fnic, FNIC_FLAGS_IO_BLOCKED))) return SCSI_MLQUEUE_HOST_BUSY; @@ -509,6 +510,13 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_ } } + /* + * Will acquire lock defore setting to IO initialized. + */ + + io_lock = fnic_io_lock_hash(fnic, sc); + spin_lock_irqsave(io_lock, flags); + /* initialize rest of io_req */ io_req->port_id = rport->port_id; io_req->start_time = jiffies; @@ -525,11 +533,9 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_ * In case another thread cancelled the request, * refetch the pointer under the lock. */ - spinlock_t *io_lock = fnic_io_lock_hash(fnic, sc); FNIC_TRACE(fnic_queuecommand, sc->device->host->host_no, sc->request->tag, sc, 0, 0, 0, (((u64)CMD_FLAGS(sc) << 32) | CMD_STATE(sc))); - spin_lock_irqsave(io_lock, flags); io_req = (struct fnic_io_req *)CMD_SP(sc); CMD_SP(sc) = NULL; CMD_STATE(sc) = FNIC_IOREQ_CMD_COMPLETE; @@ -538,6 +544,10 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_ fnic_release_ioreq_buf(fnic, io_req, sc); mempool_free(io_req, fnic->io_req_pool); } + atomic_dec(&fnic->in_flight); + /* acquire host lock before returning to SCSI */ + spin_lock(lp->host->host_lock); + return ret; } else { atomic64_inc(&fnic_stats->io_stats.active_ios); atomic64_inc(&fnic_stats->io_stats.num_ios); @@ -559,6 +569,11 @@ out: sc->request->tag, sc, io_req, sg_count, cmd_trace, (((u64)CMD_FLAGS(sc) >> 32) | CMD_STATE(sc))); + + /* if only we issued IO, will we have the io lock */ + if (CMD_FLAGS(sc) & FNIC_IO_INITIALIZED) + spin_unlock_irqrestore(io_lock, flags); + atomic_dec(&fnic->in_flight); /* acquire host lock before returning to SCSI */ spin_lock(lp->host->host_lock); |