| From e41aec79e62fa50f940cf222d1e9577f14e149dc Mon Sep 17 00:00:00 2001 |
| From: Lijun Pan <ljp@linux.ibm.com> |
| Date: Wed, 27 Jan 2021 19:34:42 -0600 |
| Subject: ibmvnic: Ensure that CRQ entry read are correctly ordered |
| |
| From: Lijun Pan <ljp@linux.ibm.com> |
| |
| commit e41aec79e62fa50f940cf222d1e9577f14e149dc upstream. |
| |
| 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> |
| Link: https://lore.kernel.org/r/20210128013442.88319-1-ljp@linux.ibm.com |
| Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/net/ethernet/ibm/ibmvnic.c | 6 ++++++ |
| 1 file changed, 6 insertions(+) |
| |
| --- a/drivers/net/ethernet/ibm/ibmvnic.c |
| +++ b/drivers/net/ethernet/ibm/ibmvnic.c |
| @@ -3682,6 +3682,12 @@ static void ibmvnic_tasklet(void *data) |
| 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; |
| } |
