linux-stable.git/drivers/md/dm-zone.c, branch linux-rolling-lts Linux kernel stable tree dm: use READ_ONCE in dm_blk_report_zones 2026-02-26T22:59:16+00:00 Mikulas Patocka mpatocka@redhat.com 2026-01-08T19:56:20+00:00 aeddfb00bb83c50a8bdfa5139f8c2c87e8d85049 [ Upstream commit e9f5a55b70ae6187ab64ef2d1232ae2738e31d1f ] The functon dm_blk_report_zones reads md->zone_revalidate_map, however it may change while the function is running. Use READ_ONCE. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Fixes: 37f53a2c60d0 ("dm: fix dm_blk_report_zones") Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e9f5a55b70ae6187ab64ef2d1232ae2738e31d1f ]

The functon dm_blk_report_zones reads md->zone_revalidate_map, however it
may change while the function is running. Use READ_ONCE.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 37f53a2c60d0 ("dm: fix dm_blk_report_zones")
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dm: fix unlocked test for dm_suspended_md 2026-02-26T22:59:16+00:00 Mikulas Patocka mpatocka@redhat.com 2026-01-08T19:55:08+00:00 7a3385e97af2b6f485fef11e82d8c29adee4be93 [ Upstream commit 24c405fdbe215c45e57bba672cc42859038491ee ] The function dm_blk_report_zones tests if the device is suspended with the "dm_suspended_md" call. However, this function is called without holding any locks, so the device may be suspended just after it. Move the call to dm_suspended_md after dm_get_live_table, so that the device can't be suspended after the suspended state was tested. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Fixes: 37f53a2c60d0 ("dm: fix dm_blk_report_zones") Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 24c405fdbe215c45e57bba672cc42859038491ee ]

The function dm_blk_report_zones tests if the device is suspended with
the "dm_suspended_md" call. However, this function is called without
holding any locks, so the device may be suspended just after it.

Move the call to dm_suspended_md after dm_get_live_table, so that the
device can't be suspended after the suspended state was tested.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 37f53a2c60d0 ("dm: fix dm_blk_report_zones")
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dm: Remove unnecessary return in dm_zone_endio() 2025-06-27T10:59:11+00:00 Damien Le Moal dlemoal@kernel.org 2025-06-11T01:14:56+00:00 d142643c06bcbc8be173a4d749adf42dd798a617 The return statement at the end of dm_zone_endio() is not needed. Remove it. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> 
The return statement at the end of dm_zone_endio() is not needed.
Remove it.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
dm-zone: Use bdev_*() helper functions where applicable 2025-05-15T13:55:07+00:00 Bart Van Assche bvanassche@acm.org 2025-05-14T20:50:33+00:00 241b9b584d50e01f7eb50c0555aa570502bcc8c5 Improve code readability by using bdev_is_zone_aligned() and bdev_offset_from_zone_start() where applicable. No functionality has been changed. This patch is a reworked version of a patch from Pankaj Raghav. See also https://lore.kernel.org/linux-block/20220923173618.6899-11-p.raghav@samsung.com/. Cc: Damien Le Moal <dlemoal@kernel.org> Cc: Pankaj Raghav <p.raghav@samsung.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> 
Improve code readability by using bdev_is_zone_aligned() and
bdev_offset_from_zone_start() where applicable. No functionality
has been changed.

This patch is a reworked version of a patch from Pankaj Raghav.

See also https://lore.kernel.org/linux-block/20220923173618.6899-11-p.raghav@samsung.com/.

Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
dm: fix native zone append devices on top of emulated ones 2025-05-04T09:35:05+00:00 Benjamin Marzinski bmarzins@redhat.com 2025-04-10T19:49:43+00:00 ad320ae27661f91585e00c114d1b264130f1bebe If a DM device that can pass down zone append commands is stacked on top of a device that emulates zone append commands, it will allocate zone append emulation resources, even though it doesn't use them. This is because the underlying device will have max_hw_zone_append_sectors set to 0 to request zone append emulation. When the DM device is stacked on top of it, it will inherit that max_hw_zone_append_sectors limit, despite being able to pass down zone append bios. Solve this by making sure max_hw_zone_append_sectors is non-zero for DM devices that do not need zone append emulation. Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Tested-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> 
If a DM device that can pass down zone append commands is stacked on top
of a device that emulates zone append commands, it will allocate zone
append emulation resources, even though it doesn't use them. This is
because the underlying device will have max_hw_zone_append_sectors set
to 0 to request zone append emulation. When the DM device is stacked on
top of it, it will inherit that max_hw_zone_append_sectors limit,
despite being able to pass down zone append bios. Solve this by making
sure max_hw_zone_append_sectors is non-zero for DM devices that do not
need zone append emulation.

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
dm: limit swapping tables for devices with zone write plugs 2025-05-04T09:35:05+00:00 Benjamin Marzinski bmarzins@redhat.com 2025-04-10T19:49:42+00:00 121218bef4c1df165181f5cd8fc3a2246bac817e dm_revalidate_zones() only allowed new or previously unzoned devices to call blk_revalidate_disk_zones(). If the device was already zoned, disk->nr_zones would always equal md->nr_zones, so dm_revalidate_zones() returned without doing any work. This would make the zoned settings for the device not match the new table. If the device had zone write plug resources, it could run into errors like bdev_zone_is_seq() reading invalid memory because disk->conv_zones_bitmap was the wrong size. If the device doesn't have any zone write plug resources, calling blk_revalidate_disk_zones() will always correctly update device. If blk_revalidate_disk_zones() fails, it can still overwrite or clear the current disk->nr_zones value. In this case, DM must restore the previous value of disk->nr_zones, so that the zoned settings will continue to match the previous value that it fell back to. If the device already has zone write plug resources, blk_revalidate_disk_zones() will not correctly update them, if it is called for arbitrary zoned device changes. Since there is not much need for this ability, the easiest solution is to disallow any table reloads that change the zoned settings, for devices that already have zone plug resources. Specifically, if a device already has zone plug resources allocated, it can only switch to another zoned table that also emulates zone append. Also, it cannot change the device size or the zone size. A device can switch to an error target. Fixes: bb37d77239af2 ("dm: introduce zone append emulation") Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Tested-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> 
dm_revalidate_zones() only allowed new or previously unzoned devices to
call blk_revalidate_disk_zones(). If the device was already zoned,
disk->nr_zones would always equal md->nr_zones, so dm_revalidate_zones()
returned without doing any work. This would make the zoned settings for
the device not match the new table. If the device had zone write plug
resources, it could run into errors like bdev_zone_is_seq() reading
invalid memory because disk->conv_zones_bitmap was the wrong size.

If the device doesn't have any zone write plug resources, calling
blk_revalidate_disk_zones() will always correctly update device.  If
blk_revalidate_disk_zones() fails, it can still overwrite or clear the
current disk->nr_zones value. In this case, DM must restore the previous
value of disk->nr_zones, so that the zoned settings will continue to
match the previous value that it fell back to.

If the device already has zone write plug resources,
blk_revalidate_disk_zones() will not correctly update them, if it is
called for arbitrary zoned device changes.  Since there is not much need
for this ability, the easiest solution is to disallow any table reloads
that change the zoned settings, for devices that already have zone plug
resources.  Specifically, if a device already has zone plug resources
allocated, it can only switch to another zoned table that also emulates
zone append.  Also, it cannot change the device size or the zone size. A
device can switch to an error target.

Fixes: bb37d77239af2 ("dm: introduce zone append emulation")
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
dm: fix dm_blk_report_zones 2025-05-04T09:34:56+00:00 Benjamin Marzinski bmarzins@redhat.com 2025-04-10T19:49:41+00:00 37f53a2c60d03743e0eacf7a0c01c279776fef4e If dm_get_live_table() returned NULL, dm_put_live_table() was never called. Also, it is possible that md->zone_revalidate_map will change while calling this function. Only read it once, so that we are always using the same value. Otherwise we might miss a call to dm_put_live_table(). Finally, while md->zone_revalidate_map is set and a process is calling blk_revalidate_disk_zones() to set up the zone append emulation resources, it is possible that another process, perhaps triggered by blkdev_report_zones_ioctl(), will call dm_blk_report_zones(). If blk_revalidate_disk_zones() fails, these resources can be freed while the other process is still using them, causing a use-after-free error. blk_revalidate_disk_zones() will only ever be called when initially setting up the zone append emulation resources, such as when setting up a zoned dm-crypt table for the first time. Further table swaps will not set md->zone_revalidate_map or call blk_revalidate_disk_zones(). However it must be called using the new table (referenced by md->zone_revalidate_map) and the new queue limits while the DM device is suspended. dm_blk_report_zones() needs some way to distinguish between a call from blk_revalidate_disk_zones(), which must be allowed to use md->zone_revalidate_map to access this not yet activated table, and all other calls to dm_blk_report_zones(), which should not be allowed while the device is suspended and cannot use md->zone_revalidate_map, since the zone resources might be freed by the process currently calling blk_revalidate_disk_zones(). Solve this by tracking the process that sets md->zone_revalidate_map in dm_revalidate_zones() and only allowing that process to make use of it in dm_blk_report_zones(). Fixes: f211268ed1f9b ("dm: Use the block layer zone append emulation") Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Tested-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> 
If dm_get_live_table() returned NULL, dm_put_live_table() was never
called. Also, it is possible that md->zone_revalidate_map will change
while calling this function. Only read it once, so that we are always
using the same value. Otherwise we might miss a call to
dm_put_live_table().

Finally, while md->zone_revalidate_map is set and a process is calling
blk_revalidate_disk_zones() to set up the zone append emulation
resources, it is possible that another process, perhaps triggered by
blkdev_report_zones_ioctl(), will call dm_blk_report_zones(). If
blk_revalidate_disk_zones() fails, these resources can be freed while
the other process is still using them, causing a use-after-free error.

blk_revalidate_disk_zones() will only ever be called when initially
setting up the zone append emulation resources, such as when setting up
a zoned dm-crypt table for the first time. Further table swaps will not
set md->zone_revalidate_map or call blk_revalidate_disk_zones().
However it must be called using the new table (referenced by
md->zone_revalidate_map) and the new queue limits while the DM device is
suspended. dm_blk_report_zones() needs some way to distinguish between a
call from blk_revalidate_disk_zones(), which must be allowed to use
md->zone_revalidate_map to access this not yet activated table, and all
other calls to dm_blk_report_zones(), which should not be allowed while
the device is suspended and cannot use md->zone_revalidate_map, since
the zone resources might be freed by the process currently calling
blk_revalidate_disk_zones().

Solve this by tracking the process that sets md->zone_revalidate_map in
dm_revalidate_zones() and only allowing that process to make use of it
in dm_blk_report_zones().

Fixes: f211268ed1f9b ("dm: Use the block layer zone append emulation")
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
dm: handle failures in dm_table_set_restrictions 2025-04-11T11:38:53+00:00 Benjamin Marzinski bmarzins@redhat.com 2025-04-10T19:49:40+00:00 4ea30ec6fb3bb598bd1df04cdfab13b1140074d2 If dm_table_set_restrictions() fails while swapping tables, device-mapper will continue using the previous table. It must be sure to leave the mapped_device in it's previous state on failure. Otherwise device-mapper could end up using the old table with settings from the unused table. Do not update the mapped device in dm_set_zones_restrictions(). Wait till after dm_table_set_restrictions() is sure to succeed to update the md zoned settings. Do the same with the dax settings, and if dm_revalidate_zones() fails, restore the original queue limits. Fixes: 7f91ccd8a608d ("dm: Call dm_revalidate_zones() after setting the queue limits") Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Tested-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> 
If dm_table_set_restrictions() fails while swapping tables,
device-mapper will continue using the previous table. It must be sure to
leave the mapped_device in it's previous state on failure.  Otherwise
device-mapper could end up using the old table with settings from the
unused table.

Do not update the mapped device in dm_set_zones_restrictions(). Wait
till after dm_table_set_restrictions() is sure to succeed to update the
md zoned settings. Do the same with the dax settings, and if
dm_revalidate_zones() fails, restore the original queue limits.

Fixes: 7f91ccd8a608d ("dm: Call dm_revalidate_zones() after setting the queue limits")
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
block: pre-calculate max_zone_append_sectors 2024-11-11T16:20:36+00:00 Christoph Hellwig hch@lst.de 2024-11-08T15:46:51+00:00 559218d43ec9dde3d2847c7aa127e88d6ab1c9ed max_zone_append_sectors differs from all other queue limits in that the final value used is not stored in the queue_limits but needs to be obtained using queue_limits_max_zone_append_sectors helper. This not only adds (tiny) extra overhead to the I/O path, but also can be easily forgotten in file system code. Add a new max_hw_zone_append_sectors value to queue_limits which is set by the driver, and calculate max_zone_append_sectors from that and the other inputs in blk_validate_zoned_limits, similar to how max_sectors is calculated to fix this. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241104073955.112324-3-hch@lst.de Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20241108154657.845768-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk> 
max_zone_append_sectors differs from all other queue limits in that the
final value used is not stored in the queue_limits but needs to be
obtained using queue_limits_max_zone_append_sectors helper.  This not
only adds (tiny) extra overhead to the I/O path, but also can be easily
forgotten in file system code.

Add a new max_hw_zone_append_sectors value to queue_limits which is
set by the driver, and calculate max_zone_append_sectors from that and
the other inputs in blk_validate_zoned_limits, similar to how
max_sectors is calculated to fix this.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241104073955.112324-3-hch@lst.de
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20241108154657.845768-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Revert "block: pre-calculate max_zone_append_sectors" 2024-11-07T12:45:34+00:00 Jens Axboe axboe@kernel.dk 2024-11-07T12:45:34+00:00 ab9bc81c1cf0efc7fc5a3aa4e562aa88d09ada57 This causes issue on, at least, nvme-mpath where my boot fails with: WARNING: CPU: 354 PID: 2729 at block/blk-settings.c:75 blk_validate_limits+0x356/0x380 Modules linked in: tg3(+) nvme usbcore scsi_mod ptp i2c_piix4 libphy nvme_core crc32c_intel scsi_common usb_common pps_core i2c_smbus CPU: 354 UID: 0 PID: 2729 Comm: kworker/u2061:1 Not tainted 6.12.0-rc6+ #181 Hardware name: Dell Inc. PowerEdge R7625/06444F, BIOS 1.8.3 04/02/2024 Workqueue: async async_run_entry_fn RIP: 0010:blk_validate_limits+0x356/0x380 Code: f6 47 01 04 75 28 83 bf 94 00 00 00 00 75 39 83 bf 98 00 00 00 00 75 34 83 7f 68 00 75 32 31 c0 83 7f 5c 00 0f 84 9b fd ff ff <0f> 0b eb 13 0f 0b eb 0f 48 c7 c0 74 12 58 92 48 89 c7 e8 13 76 46 RSP: 0018:ffffa8a1dfb93b30 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff9232829c8388 RCX: 0000000000000088 RDX: 0000000000000080 RSI: 0000000000000200 RDI: ffffa8a1dfb93c38 RBP: 000000000000000c R08: 00000000ffffffff R09: 000000000000ffff R10: 0000000000000000 R11: 0000000000000000 R12: ffff9232829b9000 R13: ffff9232829b9010 R14: ffffa8a1dfb93c38 R15: ffffa8a1dfb93c38 FS: 0000000000000000(0000) GS:ffff923867c80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c1b92480a8 CR3: 0000002484ff0002 CR4: 0000000000370ef0 Call Trace: <TASK> ? __warn+0xca/0x1a0 ? blk_validate_limits+0x356/0x380 ? report_bug+0x11a/0x1a0 ? handle_bug+0x5e/0x90 ? exc_invalid_op+0x16/0x40 ? asm_exc_invalid_op+0x16/0x20 ? blk_validate_limits+0x356/0x380 blk_alloc_queue+0x7a/0x250 __blk_alloc_disk+0x39/0x80 nvme_mpath_alloc_disk+0x13d/0x1b0 [nvme_core] nvme_scan_ns+0xcc7/0x1010 [nvme_core] async_run_entry_fn+0x27/0x120 process_scheduled_works+0x1a0/0x360 worker_thread+0x2bc/0x350 ? pr_cont_work+0x1b0/0x1b0 kthread+0x111/0x120 ? kthread_unuse_mm+0x90/0x90 ret_from_fork+0x30/0x40 ? kthread_unuse_mm+0x90/0x90 ret_from_fork_asm+0x11/0x20 </TASK> ---[ end trace 0000000000000000 ]--- presumably due to max_zone_append_sectors not being cleared to zero, resulting in blk_validate_zoned_limits() complaining and failing. This reverts commit 2a8f6153e1c2db06a537a5c9d61102eb591776f1. Signed-off-by: Jens Axboe <axboe@kernel.dk> 
This causes issue on, at least, nvme-mpath where my boot fails with:

WARNING: CPU: 354 PID: 2729 at block/blk-settings.c:75 blk_validate_limits+0x356/0x380
Modules linked in: tg3(+) nvme usbcore scsi_mod ptp i2c_piix4 libphy nvme_core crc32c_intel scsi_common usb_common pps_core i2c_smbus
CPU: 354 UID: 0 PID: 2729 Comm: kworker/u2061:1 Not tainted 6.12.0-rc6+ #181
Hardware name: Dell Inc. PowerEdge R7625/06444F, BIOS 1.8.3 04/02/2024
Workqueue: async async_run_entry_fn
RIP: 0010:blk_validate_limits+0x356/0x380
Code: f6 47 01 04 75 28 83 bf 94 00 00 00 00 75 39 83 bf 98 00 00 00 00 75 34 83 7f 68 00 75 32 31 c0 83 7f 5c 00 0f 84 9b fd ff ff <0f> 0b eb 13 0f 0b eb 0f 48 c7 c0 74 12 58 92 48 89 c7 e8 13 76 46
RSP: 0018:ffffa8a1dfb93b30 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff9232829c8388 RCX: 0000000000000088
RDX: 0000000000000080 RSI: 0000000000000200 RDI: ffffa8a1dfb93c38
RBP: 000000000000000c R08: 00000000ffffffff R09: 000000000000ffff
R10: 0000000000000000 R11: 0000000000000000 R12: ffff9232829b9000
R13: ffff9232829b9010 R14: ffffa8a1dfb93c38 R15: ffffa8a1dfb93c38
FS:  0000000000000000(0000) GS:ffff923867c80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c1b92480a8 CR3: 0000002484ff0002 CR4: 0000000000370ef0
Call Trace:
 <TASK>
 ? __warn+0xca/0x1a0
 ? blk_validate_limits+0x356/0x380
 ? report_bug+0x11a/0x1a0
 ? handle_bug+0x5e/0x90
 ? exc_invalid_op+0x16/0x40
 ? asm_exc_invalid_op+0x16/0x20
 ? blk_validate_limits+0x356/0x380
 blk_alloc_queue+0x7a/0x250
 __blk_alloc_disk+0x39/0x80
 nvme_mpath_alloc_disk+0x13d/0x1b0 [nvme_core]
 nvme_scan_ns+0xcc7/0x1010 [nvme_core]
 async_run_entry_fn+0x27/0x120
 process_scheduled_works+0x1a0/0x360
 worker_thread+0x2bc/0x350
 ? pr_cont_work+0x1b0/0x1b0
 kthread+0x111/0x120
 ? kthread_unuse_mm+0x90/0x90
 ret_from_fork+0x30/0x40
 ? kthread_unuse_mm+0x90/0x90
 ret_from_fork_asm+0x11/0x20
 </TASK>
---[ end trace 0000000000000000 ]---

presumably due to max_zone_append_sectors not being cleared to zero,
resulting in blk_validate_zoned_limits() complaining and failing.

This reverts commit 2a8f6153e1c2db06a537a5c9d61102eb591776f1.

Signed-off-by: Jens Axboe <axboe@kernel.dk>