diff options
| author | Bhanu Prakash Gollapudi <bprakash@broadcom.com> | 2011-08-05 04:38:46 +0400 |
|---|---|---|
| committer | James Bottomley <JBottomley@Parallels.com> | 2011-08-27 18:35:42 +0400 |
| commit | b338c785c5c945383046ff39092e3021ea5b1d95 (patch) | |
| tree | 548bd66957226efdd21e32eefefc222fdc593a69 /drivers/scsi/bnx2fc/bnx2fc_hwi.c | |
| parent | 81214013130cd24142f6465f7f5a256fed530c17 (diff) | |
| download | linux-b338c785c5c945383046ff39092e3021ea5b1d95.tar.xz | |
[SCSI] bnx2fc: Fix NULL pointer deref during arm_cq.
There exists a race condition between CQ doorbell unmap and IO completion path
that arms the CQ which causes a NULL dereference. Protect the ctx_base with
cq_lock to avoid this. Also, wait for the CQ doorbell to be successfully mapped
before arming the CQ.
Also, do not count uncolicited CQ completions for free_sqes.
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/bnx2fc/bnx2fc_hwi.c')
| -rw-r--r-- | drivers/scsi/bnx2fc/bnx2fc_hwi.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/scsi/bnx2fc/bnx2fc_hwi.c b/drivers/scsi/bnx2fc/bnx2fc_hwi.c index 72cfb14acd3a..b241f3d33362 100644 --- a/drivers/scsi/bnx2fc/bnx2fc_hwi.c +++ b/drivers/scsi/bnx2fc/bnx2fc_hwi.c @@ -1009,6 +1009,7 @@ int bnx2fc_process_new_cqes(struct bnx2fc_rport *tgt) u32 cq_cons; struct fcoe_cqe *cqe; u32 num_free_sqes = 0; + u32 num_cqes = 0; u16 wqe; /* @@ -1058,10 +1059,11 @@ unlock: wake_up_process(fps->iothread); else bnx2fc_process_cq_compl(tgt, wqe); + num_free_sqes++; } cqe++; tgt->cq_cons_idx++; - num_free_sqes++; + num_cqes++; if (tgt->cq_cons_idx == BNX2FC_CQ_WQES_MAX) { tgt->cq_cons_idx = 0; @@ -1070,8 +1072,10 @@ unlock: 1 - tgt->cq_curr_toggle_bit; } } - if (num_free_sqes) { - bnx2fc_arm_cq(tgt); + if (num_cqes) { + /* Arm CQ only if doorbell is mapped */ + if (tgt->ctx_base) + bnx2fc_arm_cq(tgt); atomic_add(num_free_sqes, &tgt->free_sqes); } spin_unlock_bh(&tgt->cq_lock); |