| Message ID | 20210128013442.88319-1-ljp@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [net,v3] ibmvnic: Ensure that CRQ entry read are correctly ordered | expand |
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 9778c83150f1..8820c98ea891 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -5084,6 +5084,12 @@ static void ibmvnic_tasklet(struct tasklet_struct *t) while (!done) { /* Pull all the valid messages off the CRQ */ while ((crq = ibmvnic_next_crq(adapter)) != NULL) { + /* This barrier makes sure ibmvnic_next_crq()'s + * crq->generic.first & IBMVNIC_CRQ_CMD_RSP is loaded + * before ibmvnic_handle_crq()'s + * switch(gen_crq->first) and switch(gen_crq->cmd). + */ + dma_rmb(); ibmvnic_handle_crq(crq, adapter); crq->generic.first = 0; }
Ensure that received Command-Response Queue (CRQ) entries are properly read in order by the driver. dma_rmb barrier has been added before accessing the CRQ descriptor to ensure the entire descriptor is read before processing. Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol") Signed-off-by: Lijun Pan <ljp@linux.ibm.com> --- v3: reword the comments in the code to make it less confusing. v2: drop dma_wmb according to Jakub's opinion drivers/net/ethernet/ibm/ibmvnic.c | 6 ++++++ 1 file changed, 6 insertions(+)