Re: [PATCH 0/2] qla2xxx: fix errors in PCI device remove with ongoing I/O

From: Madhani, Himanshu
Date: Tue Nov 08 2016 - 15:22:05 EST




On 11/7/16, 11:53 AM, "Mauricio Faria de Oliveira" <mauricfo@xxxxxxxxxxxxxxxxxx> wrote:

>This patchset addresses a couple of errors that might happen during
>PCI device remove (e.g., PCI hotplug, PowerVM DLPAR), which prevent
>the successful removal and re-addition of the adapter to the system,
>and cause an oops and/or invalid DMA access (triggers an EEH event).
>
>It allowed several cycles of PCI device add/remove with ongoing I/O,
>to complete successfully without triggering oopses or EEH events.
>
>Verified on v4.9-rc3.
>
>Test-case:
>---
> # lspci
> <...>
> 001d:70:00.0 Fibre Channel: QLogic Corp. ISP2532-based ...
> 001d:70:00.1 Fibre Channel: QLogic Corp. ISP2532-based ...
> <...>
>
> # for sd in $(find /sys/bus/pci/devices/001d:70:00.*/ \
> -name 'sd*' -printf "%f\n"); do \
> dd if=/dev/$sd of=/dev/null iflag=nocache & done
>
> # echo 1 | tee /sys/bus/pci/devices/001d:70:00.*/remove
> (this either works or not)
>
> # echo 1 > /sys/bus/pci/rescan
>
>Before:
>---
> <...>
> EEH: Frozen PHB#1d-PE#700000 detected
> qla2xxx [001d:70:00.1]-8042:2: PCI/Register disconnect, exiting.
> <...>
> EEH: Detected PCI bus error on PHB#29-PE#700000
> <...>
> (and/or)
> Unable to handle kernel paging request for data at address 0x00000138
> <...>
> NIP [d000000004700a40] qla2xxx_queuecommand+0x80/0x3f0 [qla2xxx]
> LR [d000000004700a10] qla2xxx_queuecommand+0x50/0x3f0 [qla2xxx]
>
> (command does not return; adapter cannot be re-added)
>
>After:
>---
> <...>
> qla2xxx [001d:70:00.0]-801c:1: Abort command issued nexus=1:0:0 -- 1 2003.
> <...>
> qla2xxx [001d:70:00.1]-801c:2: Abort command issued nexus=2:3:0 -- 1 2003.
> <...>
>
> (command does return; adapter can be re-added correctly)
>
>
>Mauricio Faria de Oliveira (2):
> qla2xxx: do not queue commands when unloading
> qla2xxx: fix invalid DMA access after command aborts in PCI device
> remove
>
> drivers/scsi/qla2xxx/qla_os.c | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
>--
>1.8.3.1
>
Thanks for the patches. Series Looks Good.

Acked-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>

>