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| author | Michael J. Ruhl <michael.j.ruhl@intel.com> | 2017-03-21 03:24:45 +0300 |
|---|---|---|
| committer | Doug Ledford <dledford@redhat.com> | 2017-04-05 21:45:09 +0300 |
| commit | 0519c520dc38e9950f4032d0f41f2b72b2c3c940 (patch) | |
| tree | 56b111fa3e75f6c09cf0b9988a55becd8ec8aa16 | |
| parent | ec8a142327f85ae9aa5ad784520e669a34839941 (diff) | |
| download | linux-0519c520dc38e9950f4032d0f41f2b72b2c3c940.tar.xz | |
IB/hfi1: Race hazard avoidance in user SDMA driver
Set the errcode before the state and add the smb_wmb() to avoid a
potential race condition with the user.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Michael Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
| -rw-r--r-- | drivers/infiniband/hw/hfi1/user_sdma.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/infiniband/hw/hfi1/user_sdma.c b/drivers/infiniband/hw/hfi1/user_sdma.c index e6811c4edc73..060e374ca37b 100644 --- a/drivers/infiniband/hw/hfi1/user_sdma.c +++ b/drivers/infiniband/hw/hfi1/user_sdma.c @@ -1615,9 +1615,10 @@ static inline void set_comp_state(struct hfi1_user_sdma_pkt_q *pq, { hfi1_cdbg(SDMA, "[%u:%u:%u:%u] Setting completion status %u %d", pq->dd->unit, pq->ctxt, pq->subctxt, idx, state, ret); - cq->comps[idx].status = state; if (state == ERROR) cq->comps[idx].errcode = -ret; + smp_wmb(); /* make sure errcode is visible first */ + cq->comps[idx].status = state; trace_hfi1_sdma_user_completion(pq->dd, pq->ctxt, pq->subctxt, idx, state, ret); } |