On Mon, Feb 6, 2017 at 8:09 PM, Jens Axboe <axboe@xxxxxx> wrote: > On 02/06/2017 05:14 PM, James Bottomley wrote: >> On Sun, 2017-02-05 at 21:13 -0800, Dan Williams wrote: >>> On Sun, Feb 5, 2017 at 1:13 AM, Christoph Hellwig <hch@xxxxxx> wrote: >>>> Dan, >>>> >>>> can you please quote your emails? I can't find any content >>>> inbetween all these quotes. >>> >>> Sorry, I'm using gmail, but I'll switch to attaching the logs. >>> >>> So with help from Xiaolong I was able to reproduce this, and it does >>> not appear to be a regression. We simply change the failure output of >>> an existing bug. Attached is a log of the same test on v4.10-rc7 >>> (i.e. without the recent block/scsi fixes), and it shows sda being >>> registered twice. >>> >>> "[ 6.647077] kobject (d5078ca4): tried to init an initialized >>> object, something is seriously wrong." >>> >>> The change that "scsi, block: fix duplicate bdi name registration >>> crashes" makes is to properly try to register sdb since the sda devt >>> is still alive. However that's not a fix because we've managed to >>> call blk_register_queue() twice on the same queue. >> >> OK, time to involve others: linux-scsi and linux-block cc'd and I've >> inserted the log below. >> >> James >> >> --- >> >> [ 5.969672] scsi host0: scsi_debug: version 1.86 [20160430] >> [ 5.969672] dev_size_mb=8, opts=0x0, submit_queues=1, statistics=0 >> [ 5.971895] scsi 0:0:0:0: Direct-Access Linux scsi_debug 0186 PQ: 0 ANSI: 7 >> [ 6.006983] sd 0:0:0:0: [sda] 16384 512-byte logical blocks: (8.39 MB/8.00 MiB) >> [ 6.026965] sd 0:0:0:0: [sda] Write Protect is off >> [ 6.027870] sd 0:0:0:0: [sda] Mode Sense: 73 00 10 08 >> [ 6.066962] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA >> [ 6.486962] sd 0:0:0:0: [sda] Attached SCSI disk >> [ 6.488377] sd 0:0:0:0: [sda] Synchronizing SCSI cache >> [ 6.489455] sd 0:0:0:0: Attached scsi generic sg0 type 0 >> [ 6.526982] sd 0:0:0:0: [sda] 16384 512-byte logical blocks: (8.39 MB/8.00 MiB) >> [ 6.546964] sd 0:0:0:0: [sda] Write Protect is off >> [ 6.547873] sd 0:0:0:0: [sda] Mode Sense: 73 00 10 08 >> [ 6.586963] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA >> [ 6.647077] kobject (d5078ca4): tried to init an initialized object, something is seriously wrong. > > So sda is probed twice, and hilarity ensues when we try to register it > twice. I can't reproduce this, using scsi_debug and with scsi_async > enabled. > > This is running linux-next? What's your .config? > The original failure report is here: http://marc.info/?l=linux-kernel&m=148619222300774&w=2 ...but it reproduces on current mainline with the same config. I haven't spotted what makes scsi_debug behave like this.