On 02/08/2017 03:48 AM, Dexuan Cui wrote: >> From: Jens Axboe [mailto:axboe@xxxxxxxxx] >> Sent: Wednesday, February 8, 2017 00:09 >> To: Dexuan Cui <decui@xxxxxxxxxxxxx>; Bart Van Assche >> <Bart.VanAssche@xxxxxxxxxxx>; hare@xxxxxxxx; hare@xxxxxxx >> Cc: hch@xxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-block@xxxxxxxxxxxxxxx; >> jth@xxxxxxxxxx >> Subject: Re: [PATCH] genhd: Do not hold event lock when scheduling workqueue >> elements >> >> On 02/06/2017 11:29 PM, Dexuan Cui wrote: >>>> From: linux-block-owner@xxxxxxxxxxxxxxx [mailto:linux-block- >>>> owner@xxxxxxxxxxxxxxx] On Behalf Of Dexuan Cui >>>> with the linux-next kernel. >>>> >>>> I can boot the guest with linux-next's next-20170130 without any issue, >>>> but since next-20170131 I haven't succeeded in booting the guest. >>>> >>>> With next-20170203 (mentioned in my mail last Friday), I got the same >>>> calltrace as Hannes. >>>> >>>> With today's linux-next (next-20170206), actually the calltrace changed to >>>> the below. >>>> [ 122.023036] ? remove_wait_queue+0x70/0x70 >>>> [ 122.051383] async_synchronize_full+0x17/0x20 >>>> [ 122.076925] do_init_module+0xc1/0x1f9 >>>> [ 122.097530] load_module+0x24bc/0x2980 >>> >>> I don't know why it hangs here, but this is the same calltrace in my >>> last-Friday mail, which contains 2 calltraces. It looks the other calltrace has >>> been resolved by some changes between next-20170203 and today. >>> >>> Here the kernel is trying to load the Hyper-V storage driver (hv_storvsc), and >>> the driver's __init and .probe have finished successfully and then the kernel >>> hangs here. >>> >>> I believe something is broken recently, because I don't have any issue before >>> Jan 31. >> >> Can you try and bisect it? >> >> Jens Axboe > > I bisected it on the branch for-4.11/next of the linux-block repo and the log shows > the first bad commit is > [e9c787e6] scsi: allocate scsi_cmnd structures as part of struct request > > # git bisect log > git bisect start > # bad: [80c6b15732f0d8830032149cbcbc8d67e074b5e8] blk-mq-sched: (un)register elevator when (un)registering queue > git bisect bad 80c6b15732f0d8830032149cbcbc8d67e074b5e8 > # good: [309bd96af9e26da3038661bf5cdad780eef49dd9] md: cleanup bio op / flags handling in raid1_write_request > git bisect good 309bd96af9e26da3038661bf5cdad780eef49dd9 > # bad: [27410a8927fb89bd150de08d749a8ed7f67b7739] nbd: remove REQ_TYPE_DRV_PRIV leftovers > git bisect bad 27410a8927fb89bd150de08d749a8ed7f67b7739 > # bad: [e9c787e65c0c36529745be47d490d998b4b6e589] scsi: allocate scsi_cmnd structures as part of struct request > git bisect bad e9c787e65c0c36529745be47d490d998b4b6e589 > # good: [3278255741326b6d66d8ca7d1cb2c57633ee43d9] scsi_dh_rdac: switch to scsi_execute_req_flags() > git bisect good 3278255741326b6d66d8ca7d1cb2c57633ee43d9 > # good: [0fbc3e0ff623f1012e7c2af96e781eeb26bcc0d7] scsi: remove gfp_flags member in scsi_host_cmd_pool > git bisect good 0fbc3e0ff623f1012e7c2af96e781eeb26bcc0d7 > # good: [eeff68c5618c8d0920b14533c70b2df007bd94b4] scsi: remove scsi_cmd_dma_pool > git bisect good eeff68c5618c8d0920b14533c70b2df007bd94b4 > # good: [d48777a633d6fa7ccde0f0e6509f0c01fbfc5299] scsi: remove __scsi_alloc_queue > git bisect good d48777a633d6fa7ccde0f0e6509f0c01fbfc5299 > # first bad commit: [e9c787e65c0c36529745be47d490d998b4b6e589] scsi: allocate scsi_cmnd structures as part of struct request Christoph? I've changed the subject line, this issue has nothing to do with the issue that Hannes was attempting to fix. -- Jens Axboe
