| Message ID | 1521704940-45406-1-git-send-email-shawn.lin@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 22/03/18 09:49, Shawn Lin wrote: > dd if=/dev/urandom of=/dev/mmcblk1 bs=4k count=10000 > with a SD card hotplug during transfer reports a warning below: What kernel version / commit was it? > > Remove the disk, partition and bdi sysfs attributes before cleaning > up the request queue associated with the disk. > > [ 410.331226] mmc1: card 59b4 removed > [ 410.348583] WARNING: CPU: 0 PID: 5 at block/blk-core.c:785 > blk_cleanup_queue+0x138/0x140 > [ 410.349294] Modules linked in: > [ 410.349570] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted > 4.16.0-rc6-next-20180321-00004-gc2ad6a7 #263 > [ 410.350363] Hardware name: Excavator-RK3399 Board (DT) > [ 410.350819] Workqueue: events_freezable mmc_rescan > [ 410.351242] pstate: 60000005 (nZCv daif -PAN -UAO) > [ 410.351663] pc : blk_cleanup_queue+0x138/0x140 > [ 410.352054] lr : blk_cleanup_queue+0xac/0x140 > [ 410.352436] sp : ffff0000092cbb90 > [ 410.352727] x29: ffff0000092cbb90 x28: 0000000000000000 > [ 410.353195] x27: ffff8000f6f23030 x26: ffff00000904e610 > [ 410.353662] x25: ffff8000f17cc808 x24: ffff8000f1038200 > [ 410.354128] x23: 0000000000000060 x22: 0000000000000000 > [ 410.354595] x21: ffff8000f11748d8 x20: ffff8000f1038200 > [ 410.355061] x19: ffff8000f1174200 x18: 0000ffff936347d8 > [ 410.355528] x17: 0000ffff935b93c0 x16: ffff0000081263f8 > [ 410.355994] x15: 0000000000000000 x14: 0000000000000400 > [ 410.356461] x13: 0000000000000001 x12: 0000000000000001 > [ 410.356927] x11: 0000000000000040 x10: ffff8000f2400028 > [ 410.357393] x9 : ffff8000f2400040 x8 : 0000000000000000 > [ 410.357860] x7 : ffff8000f6f3a340 x6 : ffff8000f6f3a340 > [ 410.358326] x5 : ffff8000f2400000 x4 : ffff8000f6f3a340 > [ 410.358792] x3 : 0000000000000000 x2 : 39c1333e45670800 > [ 410.359259] x1 : 0000000000000000 x0 : 0000000000000003 > [ 410.359726] Call trace: > [ 410.359943] blk_cleanup_queue+0x138/0x140 > [ 410.360305] mmc_cleanup_queue+0x2c/0x48 > [ 410.360652] mmc_blk_remove_req+0x1c/0x98 > [ 410.361005] mmc_blk_remove+0x180/0x1c0 > [ 410.361343] mmc_bus_remove+0x1c/0x28 > [ 410.361670] device_release_driver_internal+0x154/0x1f0 > [ 410.362128] device_release_driver+0x14/0x20 > [ 410.362504] bus_remove_device+0xc8/0x108 > [ 410.362858] device_del+0x120/0x350 > [ 410.363167] mmc_remove_card+0x5c/0xb8 > [ 410.363498] mmc_sd_detect+0x40/0x78 > [ 410.363813] mmc_rescan+0x19c/0x368 > [ 410.364123] process_one_work+0x1ac/0x318 > [ 410.364477] worker_thread+0x50/0x450 > [ 410.364801] kthread+0xf8/0x128 > [ 410.365081] ret_from_fork+0x10/0x18 > [ 410.365395] ---[ end trace 268e87a46c28968c ]--- > > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > --- > > drivers/mmc/core/block.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > index a2b9c25..02485e3 100644 > --- a/drivers/mmc/core/block.c > +++ b/drivers/mmc/core/block.c > @@ -2659,7 +2659,6 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md) > * from being accepted. > */ > card = md->queue.card; > - mmc_cleanup_queue(&md->queue); > if (md->disk->flags & GENHD_FL_UP) { > device_remove_file(disk_to_dev(md->disk), &md->force_ro); > if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && > @@ -2669,6 +2668,7 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md) > > del_gendisk(md->disk); > } > + mmc_cleanup_queue(&md->queue); > mmc_blk_put(md); > } > } >
On 2018/3/22 16:26, Adrian Hunter wrote: > On 22/03/18 09:49, Shawn Lin wrote: >> dd if=/dev/urandom of=/dev/mmcblk1 bs=4k count=10000 >> with a SD card hotplug during transfer reports a warning below: > > What kernel version / commit was it? Actually the log below has it, it is clean : 4.16.0-rc6-next-20180321 > >> >> Remove the disk, partition and bdi sysfs attributes before cleaning >> up the request queue associated with the disk. >> >> [ 410.331226] mmc1: card 59b4 removed >> [ 410.348583] WARNING: CPU: 0 PID: 5 at block/blk-core.c:785 >> blk_cleanup_queue+0x138/0x140 >> [ 410.349294] Modules linked in: >> [ 410.349570] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted >> 4.16.0-rc6-next-20180321-00004-gc2ad6a7 #263 >> [ 410.350363] Hardware name: Excavator-RK3399 Board (DT) >> [ 410.350819] Workqueue: events_freezable mmc_rescan >> [ 410.351242] pstate: 60000005 (nZCv daif -PAN -UAO) >> [ 410.351663] pc : blk_cleanup_queue+0x138/0x140 >> [ 410.352054] lr : blk_cleanup_queue+0xac/0x140 >> [ 410.352436] sp : ffff0000092cbb90 >> [ 410.352727] x29: ffff0000092cbb90 x28: 0000000000000000 >> [ 410.353195] x27: ffff8000f6f23030 x26: ffff00000904e610 >> [ 410.353662] x25: ffff8000f17cc808 x24: ffff8000f1038200 >> [ 410.354128] x23: 0000000000000060 x22: 0000000000000000 >> [ 410.354595] x21: ffff8000f11748d8 x20: ffff8000f1038200 >> [ 410.355061] x19: ffff8000f1174200 x18: 0000ffff936347d8 >> [ 410.355528] x17: 0000ffff935b93c0 x16: ffff0000081263f8 >> [ 410.355994] x15: 0000000000000000 x14: 0000000000000400 >> [ 410.356461] x13: 0000000000000001 x12: 0000000000000001 >> [ 410.356927] x11: 0000000000000040 x10: ffff8000f2400028 >> [ 410.357393] x9 : ffff8000f2400040 x8 : 0000000000000000 >> [ 410.357860] x7 : ffff8000f6f3a340 x6 : ffff8000f6f3a340 >> [ 410.358326] x5 : ffff8000f2400000 x4 : ffff8000f6f3a340 >> [ 410.358792] x3 : 0000000000000000 x2 : 39c1333e45670800 >> [ 410.359259] x1 : 0000000000000000 x0 : 0000000000000003 >> [ 410.359726] Call trace: >> [ 410.359943] blk_cleanup_queue+0x138/0x140 >> [ 410.360305] mmc_cleanup_queue+0x2c/0x48 >> [ 410.360652] mmc_blk_remove_req+0x1c/0x98 >> [ 410.361005] mmc_blk_remove+0x180/0x1c0 >> [ 410.361343] mmc_bus_remove+0x1c/0x28 >> [ 410.361670] device_release_driver_internal+0x154/0x1f0 >> [ 410.362128] device_release_driver+0x14/0x20 >> [ 410.362504] bus_remove_device+0xc8/0x108 >> [ 410.362858] device_del+0x120/0x350 >> [ 410.363167] mmc_remove_card+0x5c/0xb8 >> [ 410.363498] mmc_sd_detect+0x40/0x78 >> [ 410.363813] mmc_rescan+0x19c/0x368 >> [ 410.364123] process_one_work+0x1ac/0x318 >> [ 410.364477] worker_thread+0x50/0x450 >> [ 410.364801] kthread+0xf8/0x128 >> [ 410.365081] ret_from_fork+0x10/0x18 >> [ 410.365395] ---[ end trace 268e87a46c28968c ]--- >> >> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >> --- >> >> drivers/mmc/core/block.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c >> index a2b9c25..02485e3 100644 >> --- a/drivers/mmc/core/block.c >> +++ b/drivers/mmc/core/block.c >> @@ -2659,7 +2659,6 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md) >> * from being accepted. >> */ >> card = md->queue.card; >> - mmc_cleanup_queue(&md->queue); >> if (md->disk->flags & GENHD_FL_UP) { >> device_remove_file(disk_to_dev(md->disk), &md->force_ro); >> if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && >> @@ -2669,6 +2668,7 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md) >> >> del_gendisk(md->disk); >> } >> + mmc_cleanup_queue(&md->queue); >> mmc_blk_put(md); >> } >> } >> > > > >
On 22/03/18 10:43, Shawn Lin wrote: > On 2018/3/22 16:26, Adrian Hunter wrote: >> On 22/03/18 09:49, Shawn Lin wrote: >>> dd if=/dev/urandom of=/dev/mmcblk1 bs=4k count=10000 >>> with a SD card hotplug during transfer reports a warning below: >> >> What kernel version / commit was it? > > Actually the log below has it, it is clean : 4.16.0-rc6-next-20180321 Ok so it seems to be coming from this patch in next: commit a063057d7c731cffa7d10740e8ebc2970df8dbb3 Author: Bart Van Assche <bart.vanassche@wdc.com> Date: Wed Feb 28 10:15:33 2018 -0800 block: Fix a race between request queue removal and the block cgroup controller Avoid that the following race can occur: blk_cleanup_queue() blkcg_print_blkgs() spin_lock_irq(lock) (1) spin_lock_irq(blkg->q->queue_lock) (2,5) q->queue_lock = &q->__queue_lock (3) spin_unlock_irq(lock) (4) spin_unlock_irq(blkg->q->queue_lock) (6) (1) take driver lock; (2) busy loop for driver lock; (3) override driver lock with internal lock; (4) unlock driver lock; (5) can take driver lock now; (6) but unlock internal lock. This change is safe because only the SCSI core and the NVME core keep a reference on a request queue after having called blk_cleanup_queue(). Neither driver accesses any of the removed data structures between its blk_cleanup_queue() and blk_put_queue() calls. Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Jan Kara <jack@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> > >> >>> >>> Remove the disk, partition and bdi sysfs attributes before cleaning >>> up the request queue associated with the disk. >>> >>> [ 410.331226] mmc1: card 59b4 removed >>> [ 410.348583] WARNING: CPU: 0 PID: 5 at block/blk-core.c:785 >>> blk_cleanup_queue+0x138/0x140 >>> [ 410.349294] Modules linked in: >>> [ 410.349570] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted >>> 4.16.0-rc6-next-20180321-00004-gc2ad6a7 #263 >>> [ 410.350363] Hardware name: Excavator-RK3399 Board (DT) >>> [ 410.350819] Workqueue: events_freezable mmc_rescan >>> [ 410.351242] pstate: 60000005 (nZCv daif -PAN -UAO) >>> [ 410.351663] pc : blk_cleanup_queue+0x138/0x140 >>> [ 410.352054] lr : blk_cleanup_queue+0xac/0x140 >>> [ 410.352436] sp : ffff0000092cbb90 >>> [ 410.352727] x29: ffff0000092cbb90 x28: 0000000000000000 >>> [ 410.353195] x27: ffff8000f6f23030 x26: ffff00000904e610 >>> [ 410.353662] x25: ffff8000f17cc808 x24: ffff8000f1038200 >>> [ 410.354128] x23: 0000000000000060 x22: 0000000000000000 >>> [ 410.354595] x21: ffff8000f11748d8 x20: ffff8000f1038200 >>> [ 410.355061] x19: ffff8000f1174200 x18: 0000ffff936347d8 >>> [ 410.355528] x17: 0000ffff935b93c0 x16: ffff0000081263f8 >>> [ 410.355994] x15: 0000000000000000 x14: 0000000000000400 >>> [ 410.356461] x13: 0000000000000001 x12: 0000000000000001 >>> [ 410.356927] x11: 0000000000000040 x10: ffff8000f2400028 >>> [ 410.357393] x9 : ffff8000f2400040 x8 : 0000000000000000 >>> [ 410.357860] x7 : ffff8000f6f3a340 x6 : ffff8000f6f3a340 >>> [ 410.358326] x5 : ffff8000f2400000 x4 : ffff8000f6f3a340 >>> [ 410.358792] x3 : 0000000000000000 x2 : 39c1333e45670800 >>> [ 410.359259] x1 : 0000000000000000 x0 : 0000000000000003 >>> [ 410.359726] Call trace: >>> [ 410.359943] blk_cleanup_queue+0x138/0x140 >>> [ 410.360305] mmc_cleanup_queue+0x2c/0x48 >>> [ 410.360652] mmc_blk_remove_req+0x1c/0x98 >>> [ 410.361005] mmc_blk_remove+0x180/0x1c0 >>> [ 410.361343] mmc_bus_remove+0x1c/0x28 >>> [ 410.361670] device_release_driver_internal+0x154/0x1f0 >>> [ 410.362128] device_release_driver+0x14/0x20 >>> [ 410.362504] bus_remove_device+0xc8/0x108 >>> [ 410.362858] device_del+0x120/0x350 >>> [ 410.363167] mmc_remove_card+0x5c/0xb8 >>> [ 410.363498] mmc_sd_detect+0x40/0x78 >>> [ 410.363813] mmc_rescan+0x19c/0x368 >>> [ 410.364123] process_one_work+0x1ac/0x318 >>> [ 410.364477] worker_thread+0x50/0x450 >>> [ 410.364801] kthread+0xf8/0x128 >>> [ 410.365081] ret_from_fork+0x10/0x18 >>> [ 410.365395] ---[ end trace 268e87a46c28968c ]--- >>> >>> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >>> --- >>> >>> drivers/mmc/core/block.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c >>> index a2b9c25..02485e3 100644 >>> --- a/drivers/mmc/core/block.c >>> +++ b/drivers/mmc/core/block.c >>> @@ -2659,7 +2659,6 @@ static void mmc_blk_remove_req(struct mmc_blk_data >>> *md) >>> * from being accepted. >>> */ >>> card = md->queue.card; >>> - mmc_cleanup_queue(&md->queue); >>> if (md->disk->flags & GENHD_FL_UP) { >>> device_remove_file(disk_to_dev(md->disk), &md->force_ro); >>> if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && >>> @@ -2669,6 +2668,7 @@ static void mmc_blk_remove_req(struct mmc_blk_data >>> *md) >>> del_gendisk(md->disk); >>> } >>> + mmc_cleanup_queue(&md->queue); >>> mmc_blk_put(md); >>> } >>> } >>> >> >> >> >> > >
On 22 March 2018 at 10:31, Adrian Hunter <adrian.hunter@intel.com> wrote: > On 22/03/18 10:43, Shawn Lin wrote: >> On 2018/3/22 16:26, Adrian Hunter wrote: >>> On 22/03/18 09:49, Shawn Lin wrote: >>>> dd if=/dev/urandom of=/dev/mmcblk1 bs=4k count=10000 >>>> with a SD card hotplug during transfer reports a warning below: >>> >>> What kernel version / commit was it? >> >> Actually the log below has it, it is clean : 4.16.0-rc6-next-20180321 > > Ok so it seems to be coming from this patch in next: > > commit a063057d7c731cffa7d10740e8ebc2970df8dbb3 > Author: Bart Van Assche <bart.vanassche@wdc.com> > Date: Wed Feb 28 10:15:33 2018 -0800 > > block: Fix a race between request queue removal and the block cgroup controller > > Avoid that the following race can occur: > > blk_cleanup_queue() blkcg_print_blkgs() > spin_lock_irq(lock) (1) spin_lock_irq(blkg->q->queue_lock) (2,5) > q->queue_lock = &q->__queue_lock (3) > spin_unlock_irq(lock) (4) > spin_unlock_irq(blkg->q->queue_lock) (6) > > (1) take driver lock; > (2) busy loop for driver lock; > (3) override driver lock with internal lock; > (4) unlock driver lock; > (5) can take driver lock now; > (6) but unlock internal lock. > > This change is safe because only the SCSI core and the NVME core keep > a reference on a request queue after having called blk_cleanup_queue(). > Neither driver accesses any of the removed data structures between its > blk_cleanup_queue() and blk_put_queue() calls. > > Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com> > Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> > Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> > Cc: Jan Kara <jack@suse.com> > Signed-off-by: Jens Axboe <axboe@kernel.dk> Looks like a reasonable analyze! Shawn, could you please re-post your patch to linux-block, Jens, cc:mmc-list, me and Adrian. I think the patch should be picked up by Jens and go via his tree. Kind regards Uffe > > >> >>> >>>> >>>> Remove the disk, partition and bdi sysfs attributes before cleaning >>>> up the request queue associated with the disk. >>>> >>>> [ 410.331226] mmc1: card 59b4 removed >>>> [ 410.348583] WARNING: CPU: 0 PID: 5 at block/blk-core.c:785 >>>> blk_cleanup_queue+0x138/0x140 >>>> [ 410.349294] Modules linked in: >>>> [ 410.349570] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted >>>> 4.16.0-rc6-next-20180321-00004-gc2ad6a7 #263 >>>> [ 410.350363] Hardware name: Excavator-RK3399 Board (DT) >>>> [ 410.350819] Workqueue: events_freezable mmc_rescan >>>> [ 410.351242] pstate: 60000005 (nZCv daif -PAN -UAO) >>>> [ 410.351663] pc : blk_cleanup_queue+0x138/0x140 >>>> [ 410.352054] lr : blk_cleanup_queue+0xac/0x140 >>>> [ 410.352436] sp : ffff0000092cbb90 >>>> [ 410.352727] x29: ffff0000092cbb90 x28: 0000000000000000 >>>> [ 410.353195] x27: ffff8000f6f23030 x26: ffff00000904e610 >>>> [ 410.353662] x25: ffff8000f17cc808 x24: ffff8000f1038200 >>>> [ 410.354128] x23: 0000000000000060 x22: 0000000000000000 >>>> [ 410.354595] x21: ffff8000f11748d8 x20: ffff8000f1038200 >>>> [ 410.355061] x19: ffff8000f1174200 x18: 0000ffff936347d8 >>>> [ 410.355528] x17: 0000ffff935b93c0 x16: ffff0000081263f8 >>>> [ 410.355994] x15: 0000000000000000 x14: 0000000000000400 >>>> [ 410.356461] x13: 0000000000000001 x12: 0000000000000001 >>>> [ 410.356927] x11: 0000000000000040 x10: ffff8000f2400028 >>>> [ 410.357393] x9 : ffff8000f2400040 x8 : 0000000000000000 >>>> [ 410.357860] x7 : ffff8000f6f3a340 x6 : ffff8000f6f3a340 >>>> [ 410.358326] x5 : ffff8000f2400000 x4 : ffff8000f6f3a340 >>>> [ 410.358792] x3 : 0000000000000000 x2 : 39c1333e45670800 >>>> [ 410.359259] x1 : 0000000000000000 x0 : 0000000000000003 >>>> [ 410.359726] Call trace: >>>> [ 410.359943] blk_cleanup_queue+0x138/0x140 >>>> [ 410.360305] mmc_cleanup_queue+0x2c/0x48 >>>> [ 410.360652] mmc_blk_remove_req+0x1c/0x98 >>>> [ 410.361005] mmc_blk_remove+0x180/0x1c0 >>>> [ 410.361343] mmc_bus_remove+0x1c/0x28 >>>> [ 410.361670] device_release_driver_internal+0x154/0x1f0 >>>> [ 410.362128] device_release_driver+0x14/0x20 >>>> [ 410.362504] bus_remove_device+0xc8/0x108 >>>> [ 410.362858] device_del+0x120/0x350 >>>> [ 410.363167] mmc_remove_card+0x5c/0xb8 >>>> [ 410.363498] mmc_sd_detect+0x40/0x78 >>>> [ 410.363813] mmc_rescan+0x19c/0x368 >>>> [ 410.364123] process_one_work+0x1ac/0x318 >>>> [ 410.364477] worker_thread+0x50/0x450 >>>> [ 410.364801] kthread+0xf8/0x128 >>>> [ 410.365081] ret_from_fork+0x10/0x18 >>>> [ 410.365395] ---[ end trace 268e87a46c28968c ]--- >>>> >>>> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >>>> --- >>>> >>>> drivers/mmc/core/block.c | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c >>>> index a2b9c25..02485e3 100644 >>>> --- a/drivers/mmc/core/block.c >>>> +++ b/drivers/mmc/core/block.c >>>> @@ -2659,7 +2659,6 @@ static void mmc_blk_remove_req(struct mmc_blk_data >>>> *md) >>>> * from being accepted. >>>> */ >>>> card = md->queue.card; >>>> - mmc_cleanup_queue(&md->queue); >>>> if (md->disk->flags & GENHD_FL_UP) { >>>> device_remove_file(disk_to_dev(md->disk), &md->force_ro); >>>> if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && >>>> @@ -2669,6 +2668,7 @@ static void mmc_blk_remove_req(struct mmc_blk_data >>>> *md) >>>> del_gendisk(md->disk); >>>> } >>>> + mmc_cleanup_queue(&md->queue); >>>> mmc_blk_put(md); >>>> } >>>> } >>>> >>> >>> >>> >>> >> >> >
在 2018/3/22 17:47, Ulf Hansson 写道: > On 22 March 2018 at 10:31, Adrian Hunter <adrian.hunter@intel.com> wrote: >> On 22/03/18 10:43, Shawn Lin wrote: >>> On 2018/3/22 16:26, Adrian Hunter wrote: >>>> On 22/03/18 09:49, Shawn Lin wrote: >>>>> dd if=/dev/urandom of=/dev/mmcblk1 bs=4k count=10000 >>>>> with a SD card hotplug during transfer reports a warning below: >>>> >>>> What kernel version / commit was it? >>> >>> Actually the log below has it, it is clean : 4.16.0-rc6-next-20180321 >> >> Ok so it seems to be coming from this patch in next: >> >> commit a063057d7c731cffa7d10740e8ebc2970df8dbb3 >> Author: Bart Van Assche <bart.vanassche@wdc.com> >> Date: Wed Feb 28 10:15:33 2018 -0800 >> >> block: Fix a race between request queue removal and the block cgroup controller >> >> Avoid that the following race can occur: >> >> blk_cleanup_queue() blkcg_print_blkgs() >> spin_lock_irq(lock) (1) spin_lock_irq(blkg->q->queue_lock) (2,5) >> q->queue_lock = &q->__queue_lock (3) >> spin_unlock_irq(lock) (4) >> spin_unlock_irq(blkg->q->queue_lock) (6) >> >> (1) take driver lock; >> (2) busy loop for driver lock; >> (3) override driver lock with internal lock; >> (4) unlock driver lock; >> (5) can take driver lock now; >> (6) but unlock internal lock. >> >> This change is safe because only the SCSI core and the NVME core keep >> a reference on a request queue after having called blk_cleanup_queue(). >> Neither driver accesses any of the removed data structures between its >> blk_cleanup_queue() and blk_put_queue() calls. >> >> Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com> >> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> >> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> >> Cc: Jan Kara <jack@suse.com> >> Signed-off-by: Jens Axboe <axboe@kernel.dk> > > Looks like a reasonable analyze! > > Shawn, could you please re-post your patch to linux-block, Jens, > cc:mmc-list, me and Adrian. > Sure, I have sent to Jens. > I think the patch should be picked up by Jens and go via his tree. > > Kind regards > Uffe > >> >> >>> >>>> >>>>> >>>>> Remove the disk, partition and bdi sysfs attributes before cleaning >>>>> up the request queue associated with the disk. >>>>> >>>>> [ 410.331226] mmc1: card 59b4 removed >>>>> [ 410.348583] WARNING: CPU: 0 PID: 5 at block/blk-core.c:785 >>>>> blk_cleanup_queue+0x138/0x140 >>>>> [ 410.349294] Modules linked in: >>>>> [ 410.349570] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted >>>>> 4.16.0-rc6-next-20180321-00004-gc2ad6a7 #263 >>>>> [ 410.350363] Hardware name: Excavator-RK3399 Board (DT) >>>>> [ 410.350819] Workqueue: events_freezable mmc_rescan >>>>> [ 410.351242] pstate: 60000005 (nZCv daif -PAN -UAO) >>>>> [ 410.351663] pc : blk_cleanup_queue+0x138/0x140 >>>>> [ 410.352054] lr : blk_cleanup_queue+0xac/0x140 >>>>> [ 410.352436] sp : ffff0000092cbb90 >>>>> [ 410.352727] x29: ffff0000092cbb90 x28: 0000000000000000 >>>>> [ 410.353195] x27: ffff8000f6f23030 x26: ffff00000904e610 >>>>> [ 410.353662] x25: ffff8000f17cc808 x24: ffff8000f1038200 >>>>> [ 410.354128] x23: 0000000000000060 x22: 0000000000000000 >>>>> [ 410.354595] x21: ffff8000f11748d8 x20: ffff8000f1038200 >>>>> [ 410.355061] x19: ffff8000f1174200 x18: 0000ffff936347d8 >>>>> [ 410.355528] x17: 0000ffff935b93c0 x16: ffff0000081263f8 >>>>> [ 410.355994] x15: 0000000000000000 x14: 0000000000000400 >>>>> [ 410.356461] x13: 0000000000000001 x12: 0000000000000001 >>>>> [ 410.356927] x11: 0000000000000040 x10: ffff8000f2400028 >>>>> [ 410.357393] x9 : ffff8000f2400040 x8 : 0000000000000000 >>>>> [ 410.357860] x7 : ffff8000f6f3a340 x6 : ffff8000f6f3a340 >>>>> [ 410.358326] x5 : ffff8000f2400000 x4 : ffff8000f6f3a340 >>>>> [ 410.358792] x3 : 0000000000000000 x2 : 39c1333e45670800 >>>>> [ 410.359259] x1 : 0000000000000000 x0 : 0000000000000003 >>>>> [ 410.359726] Call trace: >>>>> [ 410.359943] blk_cleanup_queue+0x138/0x140 >>>>> [ 410.360305] mmc_cleanup_queue+0x2c/0x48 >>>>> [ 410.360652] mmc_blk_remove_req+0x1c/0x98 >>>>> [ 410.361005] mmc_blk_remove+0x180/0x1c0 >>>>> [ 410.361343] mmc_bus_remove+0x1c/0x28 >>>>> [ 410.361670] device_release_driver_internal+0x154/0x1f0 >>>>> [ 410.362128] device_release_driver+0x14/0x20 >>>>> [ 410.362504] bus_remove_device+0xc8/0x108 >>>>> [ 410.362858] device_del+0x120/0x350 >>>>> [ 410.363167] mmc_remove_card+0x5c/0xb8 >>>>> [ 410.363498] mmc_sd_detect+0x40/0x78 >>>>> [ 410.363813] mmc_rescan+0x19c/0x368 >>>>> [ 410.364123] process_one_work+0x1ac/0x318 >>>>> [ 410.364477] worker_thread+0x50/0x450 >>>>> [ 410.364801] kthread+0xf8/0x128 >>>>> [ 410.365081] ret_from_fork+0x10/0x18 >>>>> [ 410.365395] ---[ end trace 268e87a46c28968c ]--- >>>>> >>>>> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >>>>> --- >>>>> >>>>> drivers/mmc/core/block.c | 2 +- >>>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>>> >>>>> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c >>>>> index a2b9c25..02485e3 100644 >>>>> --- a/drivers/mmc/core/block.c >>>>> +++ b/drivers/mmc/core/block.c >>>>> @@ -2659,7 +2659,6 @@ static void mmc_blk_remove_req(struct mmc_blk_data >>>>> *md) >>>>> * from being accepted. >>>>> */ >>>>> card = md->queue.card; >>>>> - mmc_cleanup_queue(&md->queue); >>>>> if (md->disk->flags & GENHD_FL_UP) { >>>>> device_remove_file(disk_to_dev(md->disk), &md->force_ro); >>>>> if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && >>>>> @@ -2669,6 +2668,7 @@ static void mmc_blk_remove_req(struct mmc_blk_data >>>>> *md) >>>>> del_gendisk(md->disk); >>>>> } >>>>> + mmc_cleanup_queue(&md->queue); >>>>> mmc_blk_put(md); >>>>> } >>>>> } >>>>> >>>> >>>> >>>> >>>> >>> >>> >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > > >
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index a2b9c25..02485e3 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -2659,7 +2659,6 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md) * from being accepted. */ card = md->queue.card; - mmc_cleanup_queue(&md->queue); if (md->disk->flags & GENHD_FL_UP) { device_remove_file(disk_to_dev(md->disk), &md->force_ro); if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && @@ -2669,6 +2668,7 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md) del_gendisk(md->disk); } + mmc_cleanup_queue(&md->queue); mmc_blk_put(md); } }
dd if=/dev/urandom of=/dev/mmcblk1 bs=4k count=10000 with a SD card hotplug during transfer reports a warning below: Remove the disk, partition and bdi sysfs attributes before cleaning up the request queue associated with the disk. [ 410.331226] mmc1: card 59b4 removed [ 410.348583] WARNING: CPU: 0 PID: 5 at block/blk-core.c:785 blk_cleanup_queue+0x138/0x140 [ 410.349294] Modules linked in: [ 410.349570] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 4.16.0-rc6-next-20180321-00004-gc2ad6a7 #263 [ 410.350363] Hardware name: Excavator-RK3399 Board (DT) [ 410.350819] Workqueue: events_freezable mmc_rescan [ 410.351242] pstate: 60000005 (nZCv daif -PAN -UAO) [ 410.351663] pc : blk_cleanup_queue+0x138/0x140 [ 410.352054] lr : blk_cleanup_queue+0xac/0x140 [ 410.352436] sp : ffff0000092cbb90 [ 410.352727] x29: ffff0000092cbb90 x28: 0000000000000000 [ 410.353195] x27: ffff8000f6f23030 x26: ffff00000904e610 [ 410.353662] x25: ffff8000f17cc808 x24: ffff8000f1038200 [ 410.354128] x23: 0000000000000060 x22: 0000000000000000 [ 410.354595] x21: ffff8000f11748d8 x20: ffff8000f1038200 [ 410.355061] x19: ffff8000f1174200 x18: 0000ffff936347d8 [ 410.355528] x17: 0000ffff935b93c0 x16: ffff0000081263f8 [ 410.355994] x15: 0000000000000000 x14: 0000000000000400 [ 410.356461] x13: 0000000000000001 x12: 0000000000000001 [ 410.356927] x11: 0000000000000040 x10: ffff8000f2400028 [ 410.357393] x9 : ffff8000f2400040 x8 : 0000000000000000 [ 410.357860] x7 : ffff8000f6f3a340 x6 : ffff8000f6f3a340 [ 410.358326] x5 : ffff8000f2400000 x4 : ffff8000f6f3a340 [ 410.358792] x3 : 0000000000000000 x2 : 39c1333e45670800 [ 410.359259] x1 : 0000000000000000 x0 : 0000000000000003 [ 410.359726] Call trace: [ 410.359943] blk_cleanup_queue+0x138/0x140 [ 410.360305] mmc_cleanup_queue+0x2c/0x48 [ 410.360652] mmc_blk_remove_req+0x1c/0x98 [ 410.361005] mmc_blk_remove+0x180/0x1c0 [ 410.361343] mmc_bus_remove+0x1c/0x28 [ 410.361670] device_release_driver_internal+0x154/0x1f0 [ 410.362128] device_release_driver+0x14/0x20 [ 410.362504] bus_remove_device+0xc8/0x108 [ 410.362858] device_del+0x120/0x350 [ 410.363167] mmc_remove_card+0x5c/0xb8 [ 410.363498] mmc_sd_detect+0x40/0x78 [ 410.363813] mmc_rescan+0x19c/0x368 [ 410.364123] process_one_work+0x1ac/0x318 [ 410.364477] worker_thread+0x50/0x450 [ 410.364801] kthread+0xf8/0x128 [ 410.365081] ret_from_fork+0x10/0x18 [ 410.365395] ---[ end trace 268e87a46c28968c ]--- Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> --- drivers/mmc/core/block.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)