[PATCH] scsi: csiostor: add module softdep on cxgb4

[PATCH] scsi: csiostor: add module softdep on cxgb4

[Rahul Lakkireddy]

Both cxgb4 and csiostor drivers run on their own independent Physical
Function. But, when cxgb4 and csiostor are both being loaded in
parallel via modprobe, there is a race when firmware upgrade is
attempted by both the drivers.

When the cxgb4 driver initiates the firmware upgrade, it halts the
firmware and the chip until upgrade is complete. When the csiostor
driver is coming up in parallel, the firmware mailbox communication
fails with timeouts and the csiostor driver probe fails.

Add a module soft dependency on cxgb4 driver to ensure loading
csiostor triggers cxgb4 to load first when available to avoid the
firmware upgrade race.

Fixes: a3667aaed569 ("[SCSI] csiostor: Chelsio FCoE offload driver")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
---
 drivers/scsi/csiostor/csio_init.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/scsi/csiostor/csio_init.c b/drivers/scsi/csiostor/csio_init.c
index 390b07bf92b9..ccbded3353bd 100644
--- a/drivers/scsi/csiostor/csio_init.c
+++ b/drivers/scsi/csiostor/csio_init.c
@@ -1254,3 +1254,4 @@ MODULE_DEVICE_TABLE(pci, csio_pci_tbl);
 MODULE_VERSION(CSIO_DRV_VERSION);
 MODULE_FIRMWARE(FW_FNAME_T5);
 MODULE_FIRMWARE(FW_FNAME_T6);
+MODULE_SOFTDEP("pre: cxgb4");
-- 
2.27.0

Re: [PATCH] scsi: csiostor: add module softdep on cxgb4

[Martin K. Petersen]

On Mon, 27 Sep 2021 21:44:08 +0530, Rahul Lakkireddy wrote:

> Both cxgb4 and csiostor drivers run on their own independent Physical
> Function. But, when cxgb4 and csiostor are both being loaded in
> parallel via modprobe, there is a race when firmware upgrade is
> attempted by both the drivers.
> 
> When the cxgb4 driver initiates the firmware upgrade, it halts the
> firmware and the chip until upgrade is complete. When the csiostor
> driver is coming up in parallel, the firmware mailbox communication
> fails with timeouts and the csiostor driver probe fails.
> 
> [...]

Applied to 5.15/scsi-fixes, thanks!

[1/1] scsi: csiostor: add module softdep on cxgb4
      https://git.kernel.org/mkp/scsi/c/79a7482249a7

-- 
Martin K. Petersen	Oracle Linux Engineering