diff options
| author | Ram Vepa <ram.vepa@qlogic.com> | 2011-05-27 15:41:55 +0200 |
|---|---|---|
| committer | Roland Dreier <roland@purestorage.com> | 2011-07-18 21:09:23 +0200 |
| commit | 4356d0b64b9be53c507f66c572c1e275b4529239 (patch) | |
| tree | 58c15fe0987ae06873f2fe8a1b188db73fbaf796 /drivers/infiniband | |
| parent | IB/qib: Add sysfs interface to read free contexts (diff) | |
| download | linux-4356d0b64b9be53c507f66c572c1e275b4529239.tar.xz linux-4356d0b64b9be53c507f66c572c1e275b4529239.zip | |
IB/qib: Fix potential deadlock with link down interrupt
There is a possibility of a deadlock due to the way locks are
acquired and released in qib_set_uevent_bits(). The function
qib_set_uevent_bits() is called in process context and it uses
spin_lock() and spin_unlock(). This same lock is acquired/released
in interrupt context which can lead to a deadlock when running on
the same cpu.
The fix is to replace spin_lock() and spin_unlock() with
spin_lock_irqsave() and spin_unlock_irqrestore() respectively in
qib_set_uevent_bits().
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Diffstat (limited to 'drivers/infiniband')
| -rw-r--r-- | drivers/infiniband/hw/qib/qib_file_ops.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/infiniband/hw/qib/qib_file_ops.c b/drivers/infiniband/hw/qib/qib_file_ops.c index a94a46001745..26253039d2c7 100644 --- a/drivers/infiniband/hw/qib/qib_file_ops.c +++ b/drivers/infiniband/hw/qib/qib_file_ops.c @@ -1905,8 +1905,9 @@ int qib_set_uevent_bits(struct qib_pportdata *ppd, const int evtbit) struct qib_ctxtdata *rcd; unsigned ctxt; int ret = 0; + unsigned long flags; - spin_lock(&ppd->dd->uctxt_lock); + spin_lock_irqsave(&ppd->dd->uctxt_lock, flags); for (ctxt = ppd->dd->first_user_ctxt; ctxt < ppd->dd->cfgctxts; ctxt++) { rcd = ppd->dd->rcd[ctxt]; @@ -1925,7 +1926,7 @@ int qib_set_uevent_bits(struct qib_pportdata *ppd, const int evtbit) ret = 1; break; } - spin_unlock(&ppd->dd->uctxt_lock); + spin_unlock_irqrestore(&ppd->dd->uctxt_lock, flags); return ret; } |