* Re: [PATCH] block: don't do revalidate zones on invalid devices [not found] <20200730112517.12816-1-johannes.thumshirn@wdc.com> @ 2020-07-30 12:32 ` Damien Le Moal 2020-07-31 7:43 ` Johannes Thumshirn 0 siblings, 1 reply; 6+ messages in thread From: Damien Le Moal @ 2020-07-30 12:32 UTC (permalink / raw) To: Johannes Thumshirn, Jens Axboe Cc: linux-block, Martin K . Petersen, linux-scsi On 2020/07/30 20:25, Johannes Thumshirn wrote: > When we loose a device for whatever reason while (re)scanning zones, we > trip over a NULL pointer in blk_revalidate_zone_cb, like in the following > log: > > sd 0:0:0:0: [sda] 3418095616 4096-byte logical blocks: (14.0 TB/12.7 TiB) > sd 0:0:0:0: [sda] 52156 zones of 65536 logical blocks > sd 0:0:0:0: [sda] Write Protect is off > sd 0:0:0:0: [sda] Mode Sense: 37 00 00 08 > sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA > sd 0:0:0:0: [sda] REPORT ZONES start lba 1065287680 failed > sd 0:0:0:0: [sda] REPORT ZONES: Result: hostbyte=0x00 driverbyte=0x08 > sd 0:0:0:0: [sda] Sense Key : 0xb [current] > sd 0:0:0:0: [sda] ASC=0x0 ASCQ=0x6 > sda: failed to revalidate zones > sd 0:0:0:0: [sda] 0 4096-byte logical blocks: (0 B/0 B) > sda: detected capacity change from 14000519643136 to 0 > ================================================================== > BUG: KASAN: null-ptr-deref in blk_revalidate_zone_cb+0x1b7/0x550 > Write of size 8 at addr 0000000000000010 by task kworker/u4:1/58 > > CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 5.8.0-rc1 #692 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 > Workqueue: events_unbound async_run_entry_fn > Call Trace: > dump_stack+0x7d/0xb0 > ? blk_revalidate_zone_cb+0x1b7/0x550 > kasan_report.cold+0x5/0x37 > ? blk_revalidate_zone_cb+0x1b7/0x550 > check_memory_region+0x145/0x1a0 > blk_revalidate_zone_cb+0x1b7/0x550 > sd_zbc_parse_report+0x1f1/0x370 > ? blk_req_zone_write_trylock+0x200/0x200 > ? sectors_to_logical+0x60/0x60 > ? blk_req_zone_write_trylock+0x200/0x200 > ? blk_req_zone_write_trylock+0x200/0x200 > sd_zbc_report_zones+0x3c4/0x5e0 > ? sd_dif_config_host+0x500/0x500 > blk_revalidate_disk_zones+0x231/0x44d > ? _raw_write_lock_irqsave+0xb0/0xb0 > ? blk_queue_free_zone_bitmaps+0xd0/0xd0 > sd_zbc_read_zones+0x8cf/0x11a0 > sd_revalidate_disk+0x305c/0x64e0 > ? __device_add_disk+0x776/0xf20 > ? read_capacity_16.part.0+0x1080/0x1080 > ? blk_alloc_devt+0x250/0x250 > ? create_object.isra.0+0x595/0xa20 > ? kasan_unpoison_shadow+0x33/0x40 > sd_probe+0x8dc/0xcd2 > really_probe+0x20e/0xaf0 > __driver_attach_async_helper+0x249/0x2d0 > async_run_entry_fn+0xbe/0x560 > process_one_work+0x764/0x1290 > ? _raw_read_unlock_irqrestore+0x30/0x30 > worker_thread+0x598/0x12f0 > ? __kthread_parkme+0xc6/0x1b0 > ? schedule+0xed/0x2c0 > ? process_one_work+0x1290/0x1290 > kthread+0x36b/0x440 > ? kthread_create_worker_on_cpu+0xa0/0xa0 > ret_from_fork+0x22/0x30 > ================================================================== > > When the device is already gone we end up with the following scenario: > The device's capacity is 0 and thus the number of zones will be 0 as well. When > allocating the bitmap for the conventional zones, we then trip over a NULL > pointer. > > So if we encounter a zoned block device with a 0 capacity, don't dare to > revalidate the zones sizes. > > Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> > --- > > Note: This is a hot-fix for 5.8, we're working on something to make a > recoverable error recoverable. > > > block/blk-zoned.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/block/blk-zoned.c b/block/blk-zoned.c > index 23831fa8701d..480dfff69a00 100644 > --- a/block/blk-zoned.c > +++ b/block/blk-zoned.c > @@ -497,6 +497,9 @@ int blk_revalidate_disk_zones(struct gendisk *disk, > if (WARN_ON_ONCE(!queue_is_mq(q))) > return -EIO; > > + if (!get_capacity(disk)) > + return -EIO; > + > /* > * Ensure that all memory allocations in this context are done as if > * GFP_NOIO was specified. > I reworked sd_zbc_read_zones() and sd_zbc_revalidate_zones() to allow recovering from simple temporary errors and avoid this problem. Will send the patch tomorrow or so after some more testing. But even with that patch applied, I think this patch makes the generic block code more solid. So: Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> -- Damien Le Moal Western Digital Research ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] block: don't do revalidate zones on invalid devices 2020-07-30 12:32 ` [PATCH] block: don't do revalidate zones on invalid devices Damien Le Moal @ 2020-07-31 7:43 ` Johannes Thumshirn 2020-07-31 8:01 ` Damien Le Moal 2020-07-31 22:33 ` Jens Axboe 0 siblings, 2 replies; 6+ messages in thread From: Johannes Thumshirn @ 2020-07-31 7:43 UTC (permalink / raw) To: Damien Le Moal, Jens Axboe; +Cc: linux-block, Martin K . Petersen, linux-scsi On 30/07/2020 14:33, Damien Le Moal wrote: > On 2020/07/30 20:25, Johannes Thumshirn wrote: >> When we loose a device for whatever reason while (re)scanning zones, we >> trip over a NULL pointer in blk_revalidate_zone_cb, like in the following >> log: >> >> sd 0:0:0:0: [sda] 3418095616 4096-byte logical blocks: (14.0 TB/12.7 TiB) >> sd 0:0:0:0: [sda] 52156 zones of 65536 logical blocks >> sd 0:0:0:0: [sda] Write Protect is off >> sd 0:0:0:0: [sda] Mode Sense: 37 00 00 08 >> sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA >> sd 0:0:0:0: [sda] REPORT ZONES start lba 1065287680 failed >> sd 0:0:0:0: [sda] REPORT ZONES: Result: hostbyte=0x00 driverbyte=0x08 >> sd 0:0:0:0: [sda] Sense Key : 0xb [current] >> sd 0:0:0:0: [sda] ASC=0x0 ASCQ=0x6 >> sda: failed to revalidate zones >> sd 0:0:0:0: [sda] 0 4096-byte logical blocks: (0 B/0 B) >> sda: detected capacity change from 14000519643136 to 0 >> ================================================================== >> BUG: KASAN: null-ptr-deref in blk_revalidate_zone_cb+0x1b7/0x550 >> Write of size 8 at addr 0000000000000010 by task kworker/u4:1/58 >> >> CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 5.8.0-rc1 #692 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 >> Workqueue: events_unbound async_run_entry_fn >> Call Trace: >> dump_stack+0x7d/0xb0 >> ? blk_revalidate_zone_cb+0x1b7/0x550 >> kasan_report.cold+0x5/0x37 >> ? blk_revalidate_zone_cb+0x1b7/0x550 >> check_memory_region+0x145/0x1a0 >> blk_revalidate_zone_cb+0x1b7/0x550 >> sd_zbc_parse_report+0x1f1/0x370 >> ? blk_req_zone_write_trylock+0x200/0x200 >> ? sectors_to_logical+0x60/0x60 >> ? blk_req_zone_write_trylock+0x200/0x200 >> ? blk_req_zone_write_trylock+0x200/0x200 >> sd_zbc_report_zones+0x3c4/0x5e0 >> ? sd_dif_config_host+0x500/0x500 >> blk_revalidate_disk_zones+0x231/0x44d >> ? _raw_write_lock_irqsave+0xb0/0xb0 >> ? blk_queue_free_zone_bitmaps+0xd0/0xd0 >> sd_zbc_read_zones+0x8cf/0x11a0 >> sd_revalidate_disk+0x305c/0x64e0 >> ? __device_add_disk+0x776/0xf20 >> ? read_capacity_16.part.0+0x1080/0x1080 >> ? blk_alloc_devt+0x250/0x250 >> ? create_object.isra.0+0x595/0xa20 >> ? kasan_unpoison_shadow+0x33/0x40 >> sd_probe+0x8dc/0xcd2 >> really_probe+0x20e/0xaf0 >> __driver_attach_async_helper+0x249/0x2d0 >> async_run_entry_fn+0xbe/0x560 >> process_one_work+0x764/0x1290 >> ? _raw_read_unlock_irqrestore+0x30/0x30 >> worker_thread+0x598/0x12f0 >> ? __kthread_parkme+0xc6/0x1b0 >> ? schedule+0xed/0x2c0 >> ? process_one_work+0x1290/0x1290 >> kthread+0x36b/0x440 >> ? kthread_create_worker_on_cpu+0xa0/0xa0 >> ret_from_fork+0x22/0x30 >> ================================================================== >> >> When the device is already gone we end up with the following scenario: >> The device's capacity is 0 and thus the number of zones will be 0 as well. When >> allocating the bitmap for the conventional zones, we then trip over a NULL >> pointer. >> >> So if we encounter a zoned block device with a 0 capacity, don't dare to >> revalidate the zones sizes. >> >> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> >> --- >> >> Note: This is a hot-fix for 5.8, we're working on something to make a >> recoverable error recoverable. >> >> >> block/blk-zoned.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/block/blk-zoned.c b/block/blk-zoned.c >> index 23831fa8701d..480dfff69a00 100644 >> --- a/block/blk-zoned.c >> +++ b/block/blk-zoned.c >> @@ -497,6 +497,9 @@ int blk_revalidate_disk_zones(struct gendisk *disk, >> if (WARN_ON_ONCE(!queue_is_mq(q))) >> return -EIO; >> >> + if (!get_capacity(disk)) >> + return -EIO; >> + >> /* >> * Ensure that all memory allocations in this context are done as if >> * GFP_NOIO was specified. >> > > I reworked sd_zbc_read_zones() and sd_zbc_revalidate_zones() to allow recovering > from simple temporary errors and avoid this problem. Will send the patch > tomorrow or so after some more testing. > > But even with that patch applied, I think this patch makes the generic block > code more solid. So: > > Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> > > Jens any chance we can still get this into 5.8? ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] block: don't do revalidate zones on invalid devices 2020-07-31 7:43 ` Johannes Thumshirn @ 2020-07-31 8:01 ` Damien Le Moal 2020-07-31 8:41 ` Johannes Thumshirn 2020-07-31 22:33 ` Jens Axboe 1 sibling, 1 reply; 6+ messages in thread From: Damien Le Moal @ 2020-07-31 8:01 UTC (permalink / raw) To: Johannes Thumshirn, Jens Axboe Cc: linux-block, Martin K . Petersen, linux-scsi On 2020/07/31 16:43, Johannes Thumshirn wrote: > On 30/07/2020 14:33, Damien Le Moal wrote: >> On 2020/07/30 20:25, Johannes Thumshirn wrote: >>> When we loose a device for whatever reason while (re)scanning zones, we >>> trip over a NULL pointer in blk_revalidate_zone_cb, like in the following >>> log: >>> >>> sd 0:0:0:0: [sda] 3418095616 4096-byte logical blocks: (14.0 TB/12.7 TiB) >>> sd 0:0:0:0: [sda] 52156 zones of 65536 logical blocks >>> sd 0:0:0:0: [sda] Write Protect is off >>> sd 0:0:0:0: [sda] Mode Sense: 37 00 00 08 >>> sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA >>> sd 0:0:0:0: [sda] REPORT ZONES start lba 1065287680 failed >>> sd 0:0:0:0: [sda] REPORT ZONES: Result: hostbyte=0x00 driverbyte=0x08 >>> sd 0:0:0:0: [sda] Sense Key : 0xb [current] >>> sd 0:0:0:0: [sda] ASC=0x0 ASCQ=0x6 >>> sda: failed to revalidate zones >>> sd 0:0:0:0: [sda] 0 4096-byte logical blocks: (0 B/0 B) >>> sda: detected capacity change from 14000519643136 to 0 >>> ================================================================== >>> BUG: KASAN: null-ptr-deref in blk_revalidate_zone_cb+0x1b7/0x550 >>> Write of size 8 at addr 0000000000000010 by task kworker/u4:1/58 >>> >>> CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 5.8.0-rc1 #692 >>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 >>> Workqueue: events_unbound async_run_entry_fn >>> Call Trace: >>> dump_stack+0x7d/0xb0 >>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>> kasan_report.cold+0x5/0x37 >>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>> check_memory_region+0x145/0x1a0 >>> blk_revalidate_zone_cb+0x1b7/0x550 >>> sd_zbc_parse_report+0x1f1/0x370 >>> ? blk_req_zone_write_trylock+0x200/0x200 >>> ? sectors_to_logical+0x60/0x60 >>> ? blk_req_zone_write_trylock+0x200/0x200 >>> ? blk_req_zone_write_trylock+0x200/0x200 >>> sd_zbc_report_zones+0x3c4/0x5e0 >>> ? sd_dif_config_host+0x500/0x500 >>> blk_revalidate_disk_zones+0x231/0x44d >>> ? _raw_write_lock_irqsave+0xb0/0xb0 >>> ? blk_queue_free_zone_bitmaps+0xd0/0xd0 >>> sd_zbc_read_zones+0x8cf/0x11a0 >>> sd_revalidate_disk+0x305c/0x64e0 >>> ? __device_add_disk+0x776/0xf20 >>> ? read_capacity_16.part.0+0x1080/0x1080 >>> ? blk_alloc_devt+0x250/0x250 >>> ? create_object.isra.0+0x595/0xa20 >>> ? kasan_unpoison_shadow+0x33/0x40 >>> sd_probe+0x8dc/0xcd2 >>> really_probe+0x20e/0xaf0 >>> __driver_attach_async_helper+0x249/0x2d0 >>> async_run_entry_fn+0xbe/0x560 >>> process_one_work+0x764/0x1290 >>> ? _raw_read_unlock_irqrestore+0x30/0x30 >>> worker_thread+0x598/0x12f0 >>> ? __kthread_parkme+0xc6/0x1b0 >>> ? schedule+0xed/0x2c0 >>> ? process_one_work+0x1290/0x1290 >>> kthread+0x36b/0x440 >>> ? kthread_create_worker_on_cpu+0xa0/0xa0 >>> ret_from_fork+0x22/0x30 >>> ================================================================== >>> >>> When the device is already gone we end up with the following scenario: >>> The device's capacity is 0 and thus the number of zones will be 0 as well. When >>> allocating the bitmap for the conventional zones, we then trip over a NULL >>> pointer. >>> >>> So if we encounter a zoned block device with a 0 capacity, don't dare to >>> revalidate the zones sizes. >>> >>> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> >>> --- >>> >>> Note: This is a hot-fix for 5.8, we're working on something to make a >>> recoverable error recoverable. >>> >>> >>> block/blk-zoned.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/block/blk-zoned.c b/block/blk-zoned.c >>> index 23831fa8701d..480dfff69a00 100644 >>> --- a/block/blk-zoned.c >>> +++ b/block/blk-zoned.c >>> @@ -497,6 +497,9 @@ int blk_revalidate_disk_zones(struct gendisk *disk, >>> if (WARN_ON_ONCE(!queue_is_mq(q))) >>> return -EIO; >>> >>> + if (!get_capacity(disk)) >>> + return -EIO; >>> + >>> /* >>> * Ensure that all memory allocations in this context are done as if >>> * GFP_NOIO was specified. >>> >> >> I reworked sd_zbc_read_zones() and sd_zbc_revalidate_zones() to allow recovering >> from simple temporary errors and avoid this problem. Will send the patch >> tomorrow or so after some more testing. >> >> But even with that patch applied, I think this patch makes the generic block >> code more solid. So: >> >> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> >> >> > > Jens any chance we can still get this into 5.8? By the way, this needs a "fixes" tag too. And probably cc stable for 5.7. Looking at 5.4 LTS, the bug is not present since there is a test on !nr_zones and the entire revalidation is different anyway (callback was introduced in 5.5 if I remember correctly). -- Damien Le Moal Western Digital Research ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] block: don't do revalidate zones on invalid devices 2020-07-31 8:01 ` Damien Le Moal @ 2020-07-31 8:41 ` Johannes Thumshirn 0 siblings, 0 replies; 6+ messages in thread From: Johannes Thumshirn @ 2020-07-31 8:41 UTC (permalink / raw) To: Damien Le Moal, Jens Axboe; +Cc: linux-block, Martin K . Petersen, linux-scsi On 31/07/2020 10:01, Damien Le Moal wrote: > On 2020/07/31 16:43, Johannes Thumshirn wrote: >> On 30/07/2020 14:33, Damien Le Moal wrote: >>> On 2020/07/30 20:25, Johannes Thumshirn wrote: >>>> When we loose a device for whatever reason while (re)scanning zones, we >>>> trip over a NULL pointer in blk_revalidate_zone_cb, like in the following >>>> log: >>>> >>>> sd 0:0:0:0: [sda] 3418095616 4096-byte logical blocks: (14.0 TB/12.7 TiB) >>>> sd 0:0:0:0: [sda] 52156 zones of 65536 logical blocks >>>> sd 0:0:0:0: [sda] Write Protect is off >>>> sd 0:0:0:0: [sda] Mode Sense: 37 00 00 08 >>>> sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA >>>> sd 0:0:0:0: [sda] REPORT ZONES start lba 1065287680 failed >>>> sd 0:0:0:0: [sda] REPORT ZONES: Result: hostbyte=0x00 driverbyte=0x08 >>>> sd 0:0:0:0: [sda] Sense Key : 0xb [current] >>>> sd 0:0:0:0: [sda] ASC=0x0 ASCQ=0x6 >>>> sda: failed to revalidate zones >>>> sd 0:0:0:0: [sda] 0 4096-byte logical blocks: (0 B/0 B) >>>> sda: detected capacity change from 14000519643136 to 0 >>>> ================================================================== >>>> BUG: KASAN: null-ptr-deref in blk_revalidate_zone_cb+0x1b7/0x550 >>>> Write of size 8 at addr 0000000000000010 by task kworker/u4:1/58 >>>> >>>> CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 5.8.0-rc1 #692 >>>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 >>>> Workqueue: events_unbound async_run_entry_fn >>>> Call Trace: >>>> dump_stack+0x7d/0xb0 >>>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>>> kasan_report.cold+0x5/0x37 >>>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>>> check_memory_region+0x145/0x1a0 >>>> blk_revalidate_zone_cb+0x1b7/0x550 >>>> sd_zbc_parse_report+0x1f1/0x370 >>>> ? blk_req_zone_write_trylock+0x200/0x200 >>>> ? sectors_to_logical+0x60/0x60 >>>> ? blk_req_zone_write_trylock+0x200/0x200 >>>> ? blk_req_zone_write_trylock+0x200/0x200 >>>> sd_zbc_report_zones+0x3c4/0x5e0 >>>> ? sd_dif_config_host+0x500/0x500 >>>> blk_revalidate_disk_zones+0x231/0x44d >>>> ? _raw_write_lock_irqsave+0xb0/0xb0 >>>> ? blk_queue_free_zone_bitmaps+0xd0/0xd0 >>>> sd_zbc_read_zones+0x8cf/0x11a0 >>>> sd_revalidate_disk+0x305c/0x64e0 >>>> ? __device_add_disk+0x776/0xf20 >>>> ? read_capacity_16.part.0+0x1080/0x1080 >>>> ? blk_alloc_devt+0x250/0x250 >>>> ? create_object.isra.0+0x595/0xa20 >>>> ? kasan_unpoison_shadow+0x33/0x40 >>>> sd_probe+0x8dc/0xcd2 >>>> really_probe+0x20e/0xaf0 >>>> __driver_attach_async_helper+0x249/0x2d0 >>>> async_run_entry_fn+0xbe/0x560 >>>> process_one_work+0x764/0x1290 >>>> ? _raw_read_unlock_irqrestore+0x30/0x30 >>>> worker_thread+0x598/0x12f0 >>>> ? __kthread_parkme+0xc6/0x1b0 >>>> ? schedule+0xed/0x2c0 >>>> ? process_one_work+0x1290/0x1290 >>>> kthread+0x36b/0x440 >>>> ? kthread_create_worker_on_cpu+0xa0/0xa0 >>>> ret_from_fork+0x22/0x30 >>>> ================================================================== >>>> >>>> When the device is already gone we end up with the following scenario: >>>> The device's capacity is 0 and thus the number of zones will be 0 as well. When >>>> allocating the bitmap for the conventional zones, we then trip over a NULL >>>> pointer. >>>> >>>> So if we encounter a zoned block device with a 0 capacity, don't dare to >>>> revalidate the zones sizes. >>>> >>>> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> >>>> --- >>>> >>>> Note: This is a hot-fix for 5.8, we're working on something to make a >>>> recoverable error recoverable. >>>> >>>> >>>> block/blk-zoned.c | 3 +++ >>>> 1 file changed, 3 insertions(+) >>>> >>>> diff --git a/block/blk-zoned.c b/block/blk-zoned.c >>>> index 23831fa8701d..480dfff69a00 100644 >>>> --- a/block/blk-zoned.c >>>> +++ b/block/blk-zoned.c >>>> @@ -497,6 +497,9 @@ int blk_revalidate_disk_zones(struct gendisk *disk, >>>> if (WARN_ON_ONCE(!queue_is_mq(q))) >>>> return -EIO; >>>> >>>> + if (!get_capacity(disk)) >>>> + return -EIO; >>>> + >>>> /* >>>> * Ensure that all memory allocations in this context are done as if >>>> * GFP_NOIO was specified. >>>> >>> >>> I reworked sd_zbc_read_zones() and sd_zbc_revalidate_zones() to allow recovering >>> from simple temporary errors and avoid this problem. Will send the patch >>> tomorrow or so after some more testing. >>> >>> But even with that patch applied, I think this patch makes the generic block >>> code more solid. So: >>> >>> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> >>> >>> >> >> Jens any chance we can still get this into 5.8? > > By the way, this needs a "fixes" tag too. And probably cc stable for 5.7. > Looking at 5.4 LTS, the bug is not present since there is a test on !nr_zones > and the entire revalidation is different anyway (callback was introduced in 5.5 > if I remember correctly). > > The callback got introduced with commit d41003513e61 ("block: rework zone reporting") in v5.5-rc1 but looking at blk_revalidate_zone_cb() at this commit I think passing in a gendisk with 0 capacity won't do much harm. The correct fixes tag will be: Fixes: 6c6b35491422 ("block: set the zone size in blk_revalidate_disk_zones atomically") Starting with this commit we're calculating the number of zones based on the disk's capacity unconditional of what the capacity could be. But that commit landed in v5.5 as well. ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] block: don't do revalidate zones on invalid devices 2020-07-31 7:43 ` Johannes Thumshirn 2020-07-31 8:01 ` Damien Le Moal @ 2020-07-31 22:33 ` Jens Axboe 2020-08-03 8:49 ` Johannes Thumshirn 1 sibling, 1 reply; 6+ messages in thread From: Jens Axboe @ 2020-07-31 22:33 UTC (permalink / raw) To: Johannes Thumshirn, Damien Le Moal Cc: linux-block, Martin K . Petersen, linux-scsi On 7/31/20 1:43 AM, Johannes Thumshirn wrote: > On 30/07/2020 14:33, Damien Le Moal wrote: >> On 2020/07/30 20:25, Johannes Thumshirn wrote: >>> When we loose a device for whatever reason while (re)scanning zones, we >>> trip over a NULL pointer in blk_revalidate_zone_cb, like in the following >>> log: >>> >>> sd 0:0:0:0: [sda] 3418095616 4096-byte logical blocks: (14.0 TB/12.7 TiB) >>> sd 0:0:0:0: [sda] 52156 zones of 65536 logical blocks >>> sd 0:0:0:0: [sda] Write Protect is off >>> sd 0:0:0:0: [sda] Mode Sense: 37 00 00 08 >>> sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA >>> sd 0:0:0:0: [sda] REPORT ZONES start lba 1065287680 failed >>> sd 0:0:0:0: [sda] REPORT ZONES: Result: hostbyte=0x00 driverbyte=0x08 >>> sd 0:0:0:0: [sda] Sense Key : 0xb [current] >>> sd 0:0:0:0: [sda] ASC=0x0 ASCQ=0x6 >>> sda: failed to revalidate zones >>> sd 0:0:0:0: [sda] 0 4096-byte logical blocks: (0 B/0 B) >>> sda: detected capacity change from 14000519643136 to 0 >>> ================================================================== >>> BUG: KASAN: null-ptr-deref in blk_revalidate_zone_cb+0x1b7/0x550 >>> Write of size 8 at addr 0000000000000010 by task kworker/u4:1/58 >>> >>> CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 5.8.0-rc1 #692 >>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 >>> Workqueue: events_unbound async_run_entry_fn >>> Call Trace: >>> dump_stack+0x7d/0xb0 >>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>> kasan_report.cold+0x5/0x37 >>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>> check_memory_region+0x145/0x1a0 >>> blk_revalidate_zone_cb+0x1b7/0x550 >>> sd_zbc_parse_report+0x1f1/0x370 >>> ? blk_req_zone_write_trylock+0x200/0x200 >>> ? sectors_to_logical+0x60/0x60 >>> ? blk_req_zone_write_trylock+0x200/0x200 >>> ? blk_req_zone_write_trylock+0x200/0x200 >>> sd_zbc_report_zones+0x3c4/0x5e0 >>> ? sd_dif_config_host+0x500/0x500 >>> blk_revalidate_disk_zones+0x231/0x44d >>> ? _raw_write_lock_irqsave+0xb0/0xb0 >>> ? blk_queue_free_zone_bitmaps+0xd0/0xd0 >>> sd_zbc_read_zones+0x8cf/0x11a0 >>> sd_revalidate_disk+0x305c/0x64e0 >>> ? __device_add_disk+0x776/0xf20 >>> ? read_capacity_16.part.0+0x1080/0x1080 >>> ? blk_alloc_devt+0x250/0x250 >>> ? create_object.isra.0+0x595/0xa20 >>> ? kasan_unpoison_shadow+0x33/0x40 >>> sd_probe+0x8dc/0xcd2 >>> really_probe+0x20e/0xaf0 >>> __driver_attach_async_helper+0x249/0x2d0 >>> async_run_entry_fn+0xbe/0x560 >>> process_one_work+0x764/0x1290 >>> ? _raw_read_unlock_irqrestore+0x30/0x30 >>> worker_thread+0x598/0x12f0 >>> ? __kthread_parkme+0xc6/0x1b0 >>> ? schedule+0xed/0x2c0 >>> ? process_one_work+0x1290/0x1290 >>> kthread+0x36b/0x440 >>> ? kthread_create_worker_on_cpu+0xa0/0xa0 >>> ret_from_fork+0x22/0x30 >>> ================================================================== >>> >>> When the device is already gone we end up with the following scenario: >>> The device's capacity is 0 and thus the number of zones will be 0 as well. When >>> allocating the bitmap for the conventional zones, we then trip over a NULL >>> pointer. >>> >>> So if we encounter a zoned block device with a 0 capacity, don't dare to >>> revalidate the zones sizes. >>> >>> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> >>> --- >>> >>> Note: This is a hot-fix for 5.8, we're working on something to make a >>> recoverable error recoverable. >>> >>> >>> block/blk-zoned.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/block/blk-zoned.c b/block/blk-zoned.c >>> index 23831fa8701d..480dfff69a00 100644 >>> --- a/block/blk-zoned.c >>> +++ b/block/blk-zoned.c >>> @@ -497,6 +497,9 @@ int blk_revalidate_disk_zones(struct gendisk *disk, >>> if (WARN_ON_ONCE(!queue_is_mq(q))) >>> return -EIO; >>> >>> + if (!get_capacity(disk)) >>> + return -EIO; >>> + >>> /* >>> * Ensure that all memory allocations in this context are done as if >>> * GFP_NOIO was specified. >>> >> >> I reworked sd_zbc_read_zones() and sd_zbc_revalidate_zones() to allow recovering >> from simple temporary errors and avoid this problem. Will send the patch >> tomorrow or so after some more testing. >> >> But even with that patch applied, I think this patch makes the generic block >> code more solid. So: >> >> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> >> >> > > Jens any chance we can still get this into 5.8? I'm not going to push this out now, if 5.8 is being cut on Sunday. If we happen to get an -rc8, then it's not impossible. But this isn't a regression in this merge window as far as I can tell, so really shouldn't be critical to get in. Marking it for stable etc and queueing for 5.9 may be the saner approach, imho. -- Jens Axboe ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] block: don't do revalidate zones on invalid devices 2020-07-31 22:33 ` Jens Axboe @ 2020-08-03 8:49 ` Johannes Thumshirn 0 siblings, 0 replies; 6+ messages in thread From: Johannes Thumshirn @ 2020-08-03 8:49 UTC (permalink / raw) To: Jens Axboe, Damien Le Moal; +Cc: linux-block, Martin K . Petersen, linux-scsi On 01/08/2020 00:33, Jens Axboe wrote: > On 7/31/20 1:43 AM, Johannes Thumshirn wrote: >> On 30/07/2020 14:33, Damien Le Moal wrote: >>> On 2020/07/30 20:25, Johannes Thumshirn wrote: >>>> When we loose a device for whatever reason while (re)scanning zones, we >>>> trip over a NULL pointer in blk_revalidate_zone_cb, like in the following >>>> log: >>>> >>>> sd 0:0:0:0: [sda] 3418095616 4096-byte logical blocks: (14.0 TB/12.7 TiB) >>>> sd 0:0:0:0: [sda] 52156 zones of 65536 logical blocks >>>> sd 0:0:0:0: [sda] Write Protect is off >>>> sd 0:0:0:0: [sda] Mode Sense: 37 00 00 08 >>>> sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA >>>> sd 0:0:0:0: [sda] REPORT ZONES start lba 1065287680 failed >>>> sd 0:0:0:0: [sda] REPORT ZONES: Result: hostbyte=0x00 driverbyte=0x08 >>>> sd 0:0:0:0: [sda] Sense Key : 0xb [current] >>>> sd 0:0:0:0: [sda] ASC=0x0 ASCQ=0x6 >>>> sda: failed to revalidate zones >>>> sd 0:0:0:0: [sda] 0 4096-byte logical blocks: (0 B/0 B) >>>> sda: detected capacity change from 14000519643136 to 0 >>>> ================================================================== >>>> BUG: KASAN: null-ptr-deref in blk_revalidate_zone_cb+0x1b7/0x550 >>>> Write of size 8 at addr 0000000000000010 by task kworker/u4:1/58 >>>> >>>> CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 5.8.0-rc1 #692 >>>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 >>>> Workqueue: events_unbound async_run_entry_fn >>>> Call Trace: >>>> dump_stack+0x7d/0xb0 >>>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>>> kasan_report.cold+0x5/0x37 >>>> ? blk_revalidate_zone_cb+0x1b7/0x550 >>>> check_memory_region+0x145/0x1a0 >>>> blk_revalidate_zone_cb+0x1b7/0x550 >>>> sd_zbc_parse_report+0x1f1/0x370 >>>> ? blk_req_zone_write_trylock+0x200/0x200 >>>> ? sectors_to_logical+0x60/0x60 >>>> ? blk_req_zone_write_trylock+0x200/0x200 >>>> ? blk_req_zone_write_trylock+0x200/0x200 >>>> sd_zbc_report_zones+0x3c4/0x5e0 >>>> ? sd_dif_config_host+0x500/0x500 >>>> blk_revalidate_disk_zones+0x231/0x44d >>>> ? _raw_write_lock_irqsave+0xb0/0xb0 >>>> ? blk_queue_free_zone_bitmaps+0xd0/0xd0 >>>> sd_zbc_read_zones+0x8cf/0x11a0 >>>> sd_revalidate_disk+0x305c/0x64e0 >>>> ? __device_add_disk+0x776/0xf20 >>>> ? read_capacity_16.part.0+0x1080/0x1080 >>>> ? blk_alloc_devt+0x250/0x250 >>>> ? create_object.isra.0+0x595/0xa20 >>>> ? kasan_unpoison_shadow+0x33/0x40 >>>> sd_probe+0x8dc/0xcd2 >>>> really_probe+0x20e/0xaf0 >>>> __driver_attach_async_helper+0x249/0x2d0 >>>> async_run_entry_fn+0xbe/0x560 >>>> process_one_work+0x764/0x1290 >>>> ? _raw_read_unlock_irqrestore+0x30/0x30 >>>> worker_thread+0x598/0x12f0 >>>> ? __kthread_parkme+0xc6/0x1b0 >>>> ? schedule+0xed/0x2c0 >>>> ? process_one_work+0x1290/0x1290 >>>> kthread+0x36b/0x440 >>>> ? kthread_create_worker_on_cpu+0xa0/0xa0 >>>> ret_from_fork+0x22/0x30 >>>> ================================================================== >>>> >>>> When the device is already gone we end up with the following scenario: >>>> The device's capacity is 0 and thus the number of zones will be 0 as well. When >>>> allocating the bitmap for the conventional zones, we then trip over a NULL >>>> pointer. >>>> >>>> So if we encounter a zoned block device with a 0 capacity, don't dare to >>>> revalidate the zones sizes. >>>> >>>> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> >>>> --- >>>> >>>> Note: This is a hot-fix for 5.8, we're working on something to make a >>>> recoverable error recoverable. >>>> >>>> >>>> block/blk-zoned.c | 3 +++ >>>> 1 file changed, 3 insertions(+) >>>> >>>> diff --git a/block/blk-zoned.c b/block/blk-zoned.c >>>> index 23831fa8701d..480dfff69a00 100644 >>>> --- a/block/blk-zoned.c >>>> +++ b/block/blk-zoned.c >>>> @@ -497,6 +497,9 @@ int blk_revalidate_disk_zones(struct gendisk *disk, >>>> if (WARN_ON_ONCE(!queue_is_mq(q))) >>>> return -EIO; >>>> >>>> + if (!get_capacity(disk)) >>>> + return -EIO; >>>> + >>>> /* >>>> * Ensure that all memory allocations in this context are done as if >>>> * GFP_NOIO was specified. >>>> >>> >>> I reworked sd_zbc_read_zones() and sd_zbc_revalidate_zones() to allow recovering >>> from simple temporary errors and avoid this problem. Will send the patch >>> tomorrow or so after some more testing. >>> >>> But even with that patch applied, I think this patch makes the generic block >>> code more solid. So: >>> >>> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> >>> >>> >> >> Jens any chance we can still get this into 5.8? > > I'm not going to push this out now, if 5.8 is being cut on Sunday. If we > happen to get an -rc8, then it's not impossible. > > But this isn't a regression in this merge window as far as I can tell, > so really shouldn't be critical to get in. Marking it for stable etc and > queueing for 5.9 may be the saner approach, imho. > You're right. When I wrote this I was still under the impression it's a regression I did introduce with the zone append series. Anyway, thanks for pulling in. ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-08-03 8:49 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- [not found] <20200730112517.12816-1-johannes.thumshirn@wdc.com> 2020-07-30 12:32 ` [PATCH] block: don't do revalidate zones on invalid devices Damien Le Moal 2020-07-31 7:43 ` Johannes Thumshirn 2020-07-31 8:01 ` Damien Le Moal 2020-07-31 8:41 ` Johannes Thumshirn 2020-07-31 22:33 ` Jens Axboe 2020-08-03 8:49 ` Johannes Thumshirn
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).