On 08/26/2014 03:33 PM, Jens Axboe wrote: > On 08/26/2014 03:27 PM, Jeff Moyer wrote: >> Jens Axboe <ax...@kernel.dk> writes: >> >>> On 08/26/2014 11:24 AM, Jeff Moyer wrote: >>>> Joe Lawrence <joe.lawre...@stratus.com> writes: >>>> >>>>> v2->v3: rebase to 3.16-rc2, consider return values from the >>>>> blk_mq_alloc_request leg of the blk_get_request callchain >>>>> (noted by Jeff), noted in the second patch changelog. >>>>> >>>>> blk_mq_queue_enter may return 0 or errno, which >>>>> blk_mq_alloc_request can propogate out via ERR_PTR. >>>>> __blk_mq_alloc_request doesn't include any blk_queue_dying >>>>> checks, so I'm assuming that its failures can be attributed >>>>> to -EWOULDBLOCK under !GFP_WAIT conditions. >>>>> >>>>> v1->v2: incorporate Jeff's feedback in bsg_map_hdr() and Reviewed-by >>>>> tags. >>>>> >>>>> Joe Lawrence (2): >>>>> block,scsi: verify return pointer from blk_get_request >>>>> block,scsi: fixup blk_get_request dead queue scenarios >>>> >>>> Jens, >>>> >>>> Did this patch set fall through the cracks again? >>> >>> Falling through the cracks implies that I meant to apply it and did not, >>> which was not the case. >> >> Sorry, I was mislead by our earlier conversation on this (mail inline >> below). > > I changed my mind, it didn't feel fully baked to me. > >>> But I think we're at the point now where I'm finally comfortable with >>> applying it. So, Joe, could you ensure that it applies to 3.17-rc2, >>> then I will roll it in to the updates for 3.18. >> >> Joe, you will have one hunk to modify for sure, in scsi_ioctl.c. A >> previous patch added a check for null, but ended up returning the wrong >> value (ENOMEM instead of ENODEV). > > I have applied the first one, will look over the second one and hand > apply it. Seems the NULL return was completely removed, so we _should_ > be ok on the IS_ERR() conversion, though that sort of thing always > worries me a little bit. A NULL return can quickly show up again, and > then they would all fail.
Additionally, there's still quite a few places that call blk_get_request() and don't check the error return if __GFP_WAIT is set. Since most of the point of this is to fix segfaulting on queue dead scenarios, why aren't they all converted? -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
