[0/2] Fix EH race and MQ support

Message

Tyrel Datwyler March 19, 2021, 8:50 p.m. UTC

Changes to the locking pattern protecting the event lists and handling of scsi
command completion introduced a race where an ouststanding command that EH is
waiting ifor to complete is no longer identifiable by being on the sent list, but
instead as a command that is not on the free list. This is a result of moving
commands to be completed off the sent list to a private list to be completed
outside the list lock.

Second, during MQ enablement the ibmvfc_wait_for_ops helper used during EH to
ensure commands were properely completed failed to be converted to check for
commands on the sub-queues isntead of the primary CRQ.

Tyrel Datwyler (2):
  ibmvfc: fix potential race in ibmvfc_wait_for_ops
  ibmvfc: make ibmvfc_wait_for_ops MQ aware

 drivers/scsi/ibmvscsi/ibmvfc.c | 67 +++++++++++++++++++++++++++-------
 1 file changed, 54 insertions(+), 13 deletions(-)

Comments

Martin K. Petersen March 25, 2021, 3:53 a.m. UTC | #1

On Fri, 19 Mar 2021 14:50:27 -0600, Tyrel Datwyler wrote:

> Changes to the locking pattern protecting the event lists and handling of scsi
> command completion introduced a race where an ouststanding command that EH is
> waiting ifor to complete is no longer identifiable by being on the sent list, but
> instead as a command that is not on the free list. This is a result of moving
> commands to be completed off the sent list to a private list to be completed
> outside the list lock.
> 
> [...]

Applied to 5.12/scsi-fixes, thanks!

[1/2] ibmvfc: fix potential race in ibmvfc_wait_for_ops
      https://git.kernel.org/mkp/scsi/c/8b1c9b202549
[2/2] ibmvfc: make ibmvfc_wait_for_ops MQ aware
      https://git.kernel.org/mkp/scsi/c/62fc2661482b