Commit 9d54b998 authored Jan 27, 2021 by Lijun Pan Committed by Greg Kroah-Hartman Feb 10, 2021

ibmvnic: Ensure that CRQ entry read are correctly ordered



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: 032c5e82 ("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>

parent 78dcc1b1

drivers/net/ethernet/ibm/ibmvnic.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -3496,6 +3496,12 @@ static irqreturn_t ibmvnic_interrupt(int irq, void *instance)
		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;
		}