linux-stable.git/drivers/md/raid0.c, branch linux-5.15.y Linux kernel stable tree md: raid0: account for split bio in iostat accounting 2023-09-19T10:22:40+00:00 David Jeffery djeffery@redhat.com 2023-08-16T18:13:55+00:00 30f04a41e7d701b5e77aa60e4ad3d929d861b9e9 [ Upstream commit cc22b5407e9ca76adb7efeed843146510b1b72a5 ] When a bio is split by md raid0, the newly created bio will not be tracked by md for I/O accounting. Only the portion of I/O still assigned to the original bio which was reduced by the split will be accounted for. This results in md iostat data sometimes showing I/O values far below the actual amount of data being sent through md. md_account_bio() needs to be called for all bio generated by the bio split. A simple example of the issue was generated using a raid0 device on partitions to the same device. Since all raid0 I/O then goes to one device, it makes it easy to see a gap between the md device and its sd storage. Reading an lvm device on top of the md device, the iostat output (some 0 columns and extra devices removed to make the data more compact) was: Device tps kB_read/s kB_wrtn/s kB_dscd/s kB_read md2 0.00 0.00 0.00 0.00 0 sde 0.00 0.00 0.00 0.00 0 md2 1364.00 411496.00 0.00 0.00 411496 sde 1734.00 646144.00 0.00 0.00 646144 md2 1699.00 510680.00 0.00 0.00 510680 sde 2155.00 802784.00 0.00 0.00 802784 md2 803.00 241480.00 0.00 0.00 241480 sde 1016.00 377888.00 0.00 0.00 377888 md2 0.00 0.00 0.00 0.00 0 sde 0.00 0.00 0.00 0.00 0 I/O was generated doing large direct I/O reads (12M) with dd to a linear lvm volume on top of the 4 leg raid0 device. The md2 reads were showing as roughly 2/3 of the reads to the sde device containing all of md2's raid partitions. The sum of reads to sde was 1826816 kB, which was the expected amount as it was the amount read by dd. With the patch, the total reads from md will match the reads from sde and be consistent with the amount of I/O generated. Fixes: 10764815ff47 ("md: add io accounting for raid0 and raid5") Signed-off-by: David Jeffery <djeffery@redhat.com> Tested-by: Laurence Oberman <loberman@redhat.com> Reviewed-by: Laurence Oberman <loberman@redhat.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230816181433.13289-1-djeffery@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit cc22b5407e9ca76adb7efeed843146510b1b72a5 ]

When a bio is split by md raid0, the newly created bio will not be tracked
by md for I/O accounting. Only the portion of I/O still assigned to the
original bio which was reduced by the split will be accounted for. This
results in md iostat data sometimes showing I/O values far below the actual
amount of data being sent through md.

md_account_bio() needs to be called for all bio generated by the bio split.

A simple example of the issue was generated using a raid0 device on partitions
to the same device. Since all raid0 I/O then goes to one device, it makes it
easy to see a gap between the md device and its sd storage. Reading an lvm
device on top of the md device, the iostat output (some 0 columns and extra
devices removed to make the data more compact) was:

Device             tps    kB_read/s    kB_wrtn/s    kB_dscd/s    kB_read
md2               0.00         0.00         0.00         0.00          0
sde               0.00         0.00         0.00         0.00          0
md2            1364.00    411496.00         0.00         0.00     411496
sde            1734.00    646144.00         0.00         0.00     646144
md2            1699.00    510680.00         0.00         0.00     510680
sde            2155.00    802784.00         0.00         0.00     802784
md2             803.00    241480.00         0.00         0.00     241480
sde            1016.00    377888.00         0.00         0.00     377888
md2               0.00         0.00         0.00         0.00          0
sde               0.00         0.00         0.00         0.00          0

I/O was generated doing large direct I/O reads (12M) with dd to a linear
lvm volume on top of the 4 leg raid0 device.

The md2 reads were showing as roughly 2/3 of the reads to the sde device
containing all of md2's raid partitions. The sum of reads to sde was
1826816 kB, which was the expected amount as it was the amount read by
dd. With the patch, the total reads from md will match the reads from
sde and be consistent with the amount of I/O generated.

Fixes: 10764815ff47 ("md: add io accounting for raid0 and raid5")
Signed-off-by: David Jeffery <djeffery@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230816181433.13289-1-djeffery@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
md/raid0: Fix performance regression for large sequential writes 2023-09-19T10:22:40+00:00 Jan Kara jack@suse.cz 2023-08-14T09:27:08+00:00 9643cc0b17719bd05290f028adcfca0870c05334 [ Upstream commit 319ff40a542736d67e5bce18635de35d0e7a0bff ] Commit f00d7c85be9e ("md/raid0: fix up bio splitting.") among other things changed how bio that needs to be split is submitted. Before this commit, we have split the bio, mapped and submitted each part. After this commit, we map only the first part of the split bio and submit the second part unmapped. Due to bio sorting in __submit_bio_noacct() this results in the following request ordering: 9,0 18 1181 0.525037895 15995 Q WS 1479315464 + 63392 Split off chunk-sized (1024 sectors) request: 9,0 18 1182 0.629019647 15995 X WS 1479315464 / 1479316488 Request is unaligned to the chunk so it's split in raid0_make_request(). This is the first part mapped and punted to bio_list: 8,0 18 7053 0.629020455 15995 A WS 739921928 + 1016 <- (9,0) 1479315464 Now raid0_make_request() returns, second part is postponed on bio_list. __submit_bio_noacct() resorts the bio_list, mapped request is submitted to the underlying device: 8,0 18 7054 0.629022782 15995 G WS 739921928 + 1016 Now we take another request from the bio_list which is the remainder of the original huge request. Split off another chunk-sized bit from it and the situation repeats: 9,0 18 1183 0.629024499 15995 X WS 1479316488 / 1479317512 8,16 18 6998 0.629025110 15995 A WS 739921928 + 1016 <- (9,0) 1479316488 8,16 18 6999 0.629026728 15995 G WS 739921928 + 1016 ... 9,0 18 1184 0.629032940 15995 X WS 1479317512 / 1479318536 [libnetacq-write] 8,0 18 7059 0.629033294 15995 A WS 739922952 + 1016 <- (9,0) 1479317512 8,0 18 7060 0.629033902 15995 G WS 739922952 + 1016 ... This repeats until we consume the whole original huge request. Now we finally get to processing the second parts of the split off requests (in reverse order): 8,16 18 7181 0.629161384 15995 A WS 739952640 + 8 <- (9,0) 1479377920 8,0 18 7239 0.629162140 15995 A WS 739952640 + 8 <- (9,0) 1479376896 8,16 18 7186 0.629163881 15995 A WS 739951616 + 8 <- (9,0) 1479375872 8,0 18 7242 0.629164421 15995 A WS 739951616 + 8 <- (9,0) 1479374848 ... I guess it is obvious that this IO pattern is extremely inefficient way to perform sequential IO. It also makes bio_list to grow to rather long lengths. Change raid0_make_request() to map both parts of the split bio. Since we know we are provided with at most chunk-sized bios, we will always need to split the incoming bio at most once. Fixes: f00d7c85be9e ("md/raid0: fix up bio splitting.") Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20230814092720.3931-2-jack@suse.cz Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 319ff40a542736d67e5bce18635de35d0e7a0bff ]

Commit f00d7c85be9e ("md/raid0: fix up bio splitting.") among other
things changed how bio that needs to be split is submitted. Before this
commit, we have split the bio, mapped and submitted each part. After
this commit, we map only the first part of the split bio and submit the
second part unmapped. Due to bio sorting in __submit_bio_noacct() this
results in the following request ordering:

  9,0   18     1181     0.525037895 15995  Q  WS 1479315464 + 63392

  Split off chunk-sized (1024 sectors) request:

  9,0   18     1182     0.629019647 15995  X  WS 1479315464 / 1479316488

  Request is unaligned to the chunk so it's split in
  raid0_make_request().  This is the first part mapped and punted to
  bio_list:

  8,0   18     7053     0.629020455 15995  A  WS 739921928 + 1016 <- (9,0) 1479315464

  Now raid0_make_request() returns, second part is postponed on
  bio_list. __submit_bio_noacct() resorts the bio_list, mapped request
  is submitted to the underlying device:

  8,0   18     7054     0.629022782 15995  G  WS 739921928 + 1016

  Now we take another request from the bio_list which is the remainder
  of the original huge request. Split off another chunk-sized bit from
  it and the situation repeats:

  9,0   18     1183     0.629024499 15995  X  WS 1479316488 / 1479317512
  8,16  18     6998     0.629025110 15995  A  WS 739921928 + 1016 <- (9,0) 1479316488
  8,16  18     6999     0.629026728 15995  G  WS 739921928 + 1016
  ...
  9,0   18     1184     0.629032940 15995  X  WS 1479317512 / 1479318536 [libnetacq-write]
  8,0   18     7059     0.629033294 15995  A  WS 739922952 + 1016 <- (9,0) 1479317512
  8,0   18     7060     0.629033902 15995  G  WS 739922952 + 1016
  ...

  This repeats until we consume the whole original huge request. Now we
  finally get to processing the second parts of the split off requests
  (in reverse order):

  8,16  18     7181     0.629161384 15995  A  WS 739952640 + 8 <- (9,0) 1479377920
  8,0   18     7239     0.629162140 15995  A  WS 739952640 + 8 <- (9,0) 1479376896
  8,16  18     7186     0.629163881 15995  A  WS 739951616 + 8 <- (9,0) 1479375872
  8,0   18     7242     0.629164421 15995  A  WS 739951616 + 8 <- (9,0) 1479374848
  ...

I guess it is obvious that this IO pattern is extremely inefficient way
to perform sequential IO. It also makes bio_list to grow to rather long
lengths.

Change raid0_make_request() to map both parts of the split bio. Since we
know we are provided with at most chunk-sized bios, we will always need
to split the incoming bio at most once.

Fixes: f00d7c85be9e ("md/raid0: fix up bio splitting.")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20230814092720.3931-2-jack@suse.cz
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
md/raid0: Factor out helper for mapping and submitting a bio 2023-09-19T10:22:39+00:00 Jan Kara jack@suse.cz 2023-08-14T09:27:07+00:00 17fbf7da491f927206f09d1ba361df106f5b3ddc [ Upstream commit af50e20afb401cc203bd2a9ff62ece0ae4976103 ] Factor out helper function for mapping and submitting a bio out of raid0_make_request(). We will use it later for submitting both parts of a split bio. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20230814092720.3931-1-jack@suse.cz Signed-off-by: Song Liu <song@kernel.org> Stable-dep-of: 319ff40a5427 ("md/raid0: Fix performance regression for large sequential writes") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit af50e20afb401cc203bd2a9ff62ece0ae4976103 ]

Factor out helper function for mapping and submitting a bio out of
raid0_make_request(). We will use it later for submitting both parts of
a split bio.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20230814092720.3931-1-jack@suse.cz
Signed-off-by: Song Liu <song@kernel.org>
Stable-dep-of: 319ff40a5427 ("md/raid0: Fix performance regression for large sequential writes")
Signed-off-by: Sasha Levin <sashal@kernel.org>
md: add error_handlers for raid0 and linear 2023-09-19T10:22:39+00:00 Mariusz Tkaczyk mariusz.tkaczyk@linux.intel.com 2023-03-06T13:03:17+00:00 d04f1e322f52e877f9dee230930252b98d861cdf [ Upstream commit c31fea2f8e2a72c817f318016bbc327095175a9f ] After the commit 9631abdbf406c("md: Set MD_BROKEN for RAID1 and RAID10") MD_BROKEN must be set if array is failed because state_store() checks it. If it is set then -EBUSY is returned to userspace. For raid0 and linear MD_BROKEN is not set by error_handler(). As a result mdadm is unable to trigger clean-up actions. It is a regression. This patch adds appropriate error_handler for raid0 and linear. The error handler sets MD_BROKEN for this device. Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230306130317.3418-1-mariusz.tkaczyk@linux.intel.com Stable-dep-of: 319ff40a5427 ("md/raid0: Fix performance regression for large sequential writes") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit c31fea2f8e2a72c817f318016bbc327095175a9f ]

After the commit 9631abdbf406c("md: Set MD_BROKEN for RAID1 and RAID10")
MD_BROKEN must be set if array is failed because state_store() checks it.
If it is set then -EBUSY is returned to userspace.

For raid0 and linear MD_BROKEN is not set by error_handler(). As a result
mdadm is unable to trigger clean-up actions. It is a regression.

This patch adds appropriate error_handler for raid0 and linear. The
error handler sets MD_BROKEN for this device.

Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230306130317.3418-1-mariusz.tkaczyk@linux.intel.com
Stable-dep-of: 319ff40a5427 ("md/raid0: Fix performance regression for large sequential writes")
Signed-off-by: Sasha Levin <sashal@kernel.org>
md/raid0: add discard support for the 'original' layout 2023-07-23T11:47:51+00:00 Jason Baron jbaron@akamai.com 2023-06-23T18:05:23+00:00 4f61488541bbe5c3adb34ec6e78b4d924b87b49b commit e836007089ba8fdf24e636ef2b007651fb4582e6 upstream. We've found that using raid0 with the 'original' layout and discard enabled with different disk sizes (such that at least two zones are created) can result in data corruption. This is due to the fact that the discard handling in 'raid0_handle_discard()' assumes the 'alternate' layout. We've seen this corruption using ext4 but other filesystems are likely susceptible as well. More specifically, while multiple zones are necessary to create the corruption, the corruption may not occur with multiple zones if they layout in such a way the layout matches what the 'alternate' layout would have produced. Thus, not all raid0 devices with the 'original' layout, different size disks and discard enabled will encounter this corruption. The 3.14 kernel inadvertently changed the raid0 disk layout for different size disks. Thus, running a pre-3.14 kernel and post-3.14 kernel on the same raid0 array could corrupt data. This lead to the creation of the 'original' layout (to match the pre-3.14 layout) and the 'alternate' layout (to match the post 3.14 layout) in the 5.4 kernel time frame and an option to tell the kernel which layout to use (since it couldn't be autodetected). However, when the 'original' layout was added back to 5.4 discard support for the 'original' layout was not added leading this issue. I've been able to reliably reproduce the corruption with the following test case: 1. create raid0 array with different size disks using original layout 2. mkfs 3. mount -o discard 4. create lots of files 5. remove 1/2 the files 6. fstrim -a (or just the mount point for the raid0 array) 7. umount 8. fsck -fn /dev/md0 (spews all sorts of corruptions) Let's fix this by adding proper discard support to the 'original' layout. The fix 'maps' the 'original' layout disks to the order in which they are read/written such that we can compare the disks in the same way that the current 'alternate' layout does. A 'disk_shift' field is added to 'struct strip_zone'. This could be computed on the fly in raid0_handle_discard() but by adding this field, we save some computation in the discard path. Note we could also potentially fix this by re-ordering the disks in the zones that follow the first one, and then always read/writing them using the 'alternate' layout. However, that is seen as a more substantial change, and we are attempting the least invasive fix at this time to remedy the corruption. I've verified the change using the reproducer mentioned above. Typically, the corruption is seen after less than 3 iterations, while the patch has run 500+ iterations. Cc: NeilBrown <neilb@suse.de> Cc: Song Liu <song@kernel.org> Fixes: c84a1372df92 ("md/raid0: avoid RAID0 data corruption due to layout confusion.") Cc: stable@vger.kernel.org Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230623180523.1901230-1-jbaron@akamai.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e836007089ba8fdf24e636ef2b007651fb4582e6 upstream.

We've found that using raid0 with the 'original' layout and discard
enabled with different disk sizes (such that at least two zones are
created) can result in data corruption. This is due to the fact that
the discard handling in 'raid0_handle_discard()' assumes the 'alternate'
layout. We've seen this corruption using ext4 but other filesystems are
likely susceptible as well.

More specifically, while multiple zones are necessary to create the
corruption, the corruption may not occur with multiple zones if they
layout in such a way the layout matches what the 'alternate' layout
would have produced. Thus, not all raid0 devices with the 'original'
layout, different size disks and discard enabled will encounter this
corruption.

The 3.14 kernel inadvertently changed the raid0 disk layout for different
size disks. Thus, running a pre-3.14 kernel and post-3.14 kernel on the
same raid0 array could corrupt data. This lead to the creation of the
'original' layout (to match the pre-3.14 layout) and the 'alternate' layout
(to match the post 3.14 layout) in the 5.4 kernel time frame and an option
to tell the kernel which layout to use (since it couldn't be autodetected).
However, when the 'original' layout was added back to 5.4 discard support
for the 'original' layout was not added leading this issue.

I've been able to reliably reproduce the corruption with the following
test case:

1. create raid0 array with different size disks using original layout
2. mkfs
3. mount -o discard
4. create lots of files
5. remove 1/2 the files
6. fstrim -a (or just the mount point for the raid0 array)
7. umount
8. fsck -fn /dev/md0 (spews all sorts of corruptions)

Let's fix this by adding proper discard support to the 'original' layout.
The fix 'maps' the 'original' layout disks to the order in which they are
read/written such that we can compare the disks in the same way that the
current 'alternate' layout does. A 'disk_shift' field is added to
'struct strip_zone'. This could be computed on the fly in
raid0_handle_discard() but by adding this field, we save some computation
in the discard path.

Note we could also potentially fix this by re-ordering the disks in the
zones that follow the first one, and then always read/writing them using
the 'alternate' layout. However, that is seen as a more substantial change,
and we are attempting the least invasive fix at this time to remedy the
corruption.

I've verified the change using the reproducer mentioned above. Typically,
the corruption is seen after less than 3 iterations, while the patch has
run 500+ iterations.

Cc: NeilBrown <neilb@suse.de>
Cc: Song Liu <song@kernel.org>
Fixes: c84a1372df92 ("md/raid0: avoid RAID0 data corruption due to layout confusion.")
Cc: stable@vger.kernel.org
Signed-off-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230623180523.1901230-1-jbaron@akamai.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
md: Replace snprintf with scnprintf 2022-10-26T10:35:12+00:00 Saurabh Sengar ssengar@linux.microsoft.com 2022-08-23T18:51:04+00:00 5d8259c9d1915a50c60c7d6e9e7fb9b7da64a175 [ Upstream commit 1727fd5015d8f93474148f94e34cda5aa6ad4a43 ] Current code produces a warning as shown below when total characters in the constituent block device names plus the slashes exceeds 200. snprintf() returns the number of characters generated from the given input, which could cause the expression “200 – len” to wrap around to a large positive number. Fix this by using scnprintf() instead, which returns the actual number of characters written into the buffer. [ 1513.267938] ------------[ cut here ]------------ [ 1513.267943] WARNING: CPU: 15 PID: 37247 at <snip>/lib/vsprintf.c:2509 vsnprintf+0x2c8/0x510 [ 1513.267944] Modules linked in: <snip> [ 1513.267969] CPU: 15 PID: 37247 Comm: mdadm Not tainted 5.4.0-1085-azure #90~18.04.1-Ubuntu [ 1513.267969] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 1513.267971] RIP: 0010:vsnprintf+0x2c8/0x510 <-snip-> [ 1513.267982] Call Trace: [ 1513.267986] snprintf+0x45/0x70 [ 1513.267990] ? disk_name+0x71/0xa0 [ 1513.267993] dump_zones+0x114/0x240 [raid0] [ 1513.267996] ? _cond_resched+0x19/0x40 [ 1513.267998] raid0_run+0x19e/0x270 [raid0] [ 1513.268000] md_run+0x5e0/0xc50 [ 1513.268003] ? security_capable+0x3f/0x60 [ 1513.268005] do_md_run+0x19/0x110 [ 1513.268006] md_ioctl+0x195e/0x1f90 [ 1513.268007] blkdev_ioctl+0x91f/0x9f0 [ 1513.268010] block_ioctl+0x3d/0x50 [ 1513.268012] do_vfs_ioctl+0xa9/0x640 [ 1513.268014] ? __fput+0x162/0x260 [ 1513.268016] ksys_ioctl+0x75/0x80 [ 1513.268017] __x64_sys_ioctl+0x1a/0x20 [ 1513.268019] do_syscall_64+0x5e/0x200 [ 1513.268021] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 766038846e875 ("md/raid0: replace printk() with pr_*()") Reviewed-by: Michael Kelley <mikelley@microsoft.com> Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 1727fd5015d8f93474148f94e34cda5aa6ad4a43 ]

Current code produces a warning as shown below when total characters
in the constituent block device names plus the slashes exceeds 200.
snprintf() returns the number of characters generated from the given
input, which could cause the expression “200 – len” to wrap around
to a large positive number. Fix this by using scnprintf() instead,
which returns the actual number of characters written into the buffer.

[ 1513.267938] ------------[ cut here ]------------
[ 1513.267943] WARNING: CPU: 15 PID: 37247 at <snip>/lib/vsprintf.c:2509 vsnprintf+0x2c8/0x510
[ 1513.267944] Modules linked in:  <snip>
[ 1513.267969] CPU: 15 PID: 37247 Comm: mdadm Not tainted 5.4.0-1085-azure #90~18.04.1-Ubuntu
[ 1513.267969] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022
[ 1513.267971] RIP: 0010:vsnprintf+0x2c8/0x510
<-snip->
[ 1513.267982] Call Trace:
[ 1513.267986]  snprintf+0x45/0x70
[ 1513.267990]  ? disk_name+0x71/0xa0
[ 1513.267993]  dump_zones+0x114/0x240 [raid0]
[ 1513.267996]  ? _cond_resched+0x19/0x40
[ 1513.267998]  raid0_run+0x19e/0x270 [raid0]
[ 1513.268000]  md_run+0x5e0/0xc50
[ 1513.268003]  ? security_capable+0x3f/0x60
[ 1513.268005]  do_md_run+0x19/0x110
[ 1513.268006]  md_ioctl+0x195e/0x1f90
[ 1513.268007]  blkdev_ioctl+0x91f/0x9f0
[ 1513.268010]  block_ioctl+0x3d/0x50
[ 1513.268012]  do_vfs_ioctl+0xa9/0x640
[ 1513.268014]  ? __fput+0x162/0x260
[ 1513.268016]  ksys_ioctl+0x75/0x80
[ 1513.268017]  __x64_sys_ioctl+0x1a/0x20
[ 1513.268019]  do_syscall_64+0x5e/0x200
[ 1513.268021]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 766038846e875 ("md/raid0: replace printk() with pr_*()")
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
md/raid0: Ignore RAID0 layout if the second zone has only one device 2022-06-14T16:36:28+00:00 Pascal Hambourg pascal@plouf.fr.eu.org 2022-04-13T06:53:56+00:00 4c106eb8953456a2768d4e5f78888c3209f9a046 commit ea23994edc4169bd90d7a9b5908c6ccefd82fa40 upstream. The RAID0 layout is irrelevant if all members have the same size so the array has only one zone. It is *also* irrelevant if the array has two zones and the second zone has only one device, for example if the array has two members of different sizes. So in that case it makes sense to allow assembly even when the layout is undefined, like what is done when the array has only one zone. Reviewed-by: NeilBrown <neilb@suse.de> Signed-off-by: Pascal Hambourg <pascal@plouf.fr.eu.org> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ea23994edc4169bd90d7a9b5908c6ccefd82fa40 upstream.

The RAID0 layout is irrelevant if all members have the same size so the
array has only one zone. It is *also* irrelevant if the array has two
zones and the second zone has only one device, for example if the array
has two members of different sizes.

So in that case it makes sense to allow assembly even when the layout is
undefined, like what is done when the array has only one zone.

Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Pascal Hambourg <pascal@plouf.fr.eu.org>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
md: Don't set mddev private to NULL in raid0 pers->free 2022-06-09T08:23:32+00:00 Xiao Ni xni@redhat.com 2022-05-12T09:21:08+00:00 f63fd1e0e0fc158023cc67ea6a07e278019061ba commit 0f2571ad7a30ff6b33cde142439f9378669f8b4f upstream. In normal stop process, it does like this: do_md_stop | __md_stop (pers->free(); mddev->private=NULL) | md_free (free mddev) __md_stop sets mddev->private to NULL after pers->free. The raid device will be stopped and mddev memory is free. But in reshape, it doesn't free the mddev and mddev will still be used in new raid. In reshape, it first sets mddev->private to new_pers and then runs old_pers->free(). Now raid0 sets mddev->private to NULL in raid0_free. The new raid can't work anymore. It will panic when dereference mddev->private because of NULL pointer dereference. It can panic like this: [63010.814972] kernel BUG at drivers/md/raid10.c:928! [63010.819778] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [63010.825011] CPU: 3 PID: 44437 Comm: md0_resync Kdump: loaded Not tainted 5.14.0-86.el9.x86_64 #1 [63010.833789] Hardware name: Dell Inc. PowerEdge R6415/07YXFK, BIOS 1.15.0 09/11/2020 [63010.841440] RIP: 0010:raise_barrier+0x161/0x170 [raid10] [63010.865508] RSP: 0018:ffffc312408bbc10 EFLAGS: 00010246 [63010.870734] RAX: 0000000000000000 RBX: ffffa00bf7d39800 RCX: 0000000000000000 [63010.877866] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffa00bf7d39800 [63010.884999] RBP: 0000000000000000 R08: fffffa4945e74400 R09: 0000000000000000 [63010.892132] R10: ffffa00eed02f798 R11: 0000000000000000 R12: ffffa00bbc435200 [63010.899266] R13: ffffa00bf7d39800 R14: 0000000000000400 R15: 0000000000000003 [63010.906399] FS: 0000000000000000(0000) GS:ffffa00eed000000(0000) knlGS:0000000000000000 [63010.914485] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [63010.920229] CR2: 00007f5cfbe99828 CR3: 0000000105efe000 CR4: 00000000003506e0 [63010.927363] Call Trace: [63010.929822] ? bio_reset+0xe/0x40 [63010.933144] ? raid10_alloc_init_r10buf+0x60/0xa0 [raid10] [63010.938629] raid10_sync_request+0x756/0x1610 [raid10] [63010.943770] md_do_sync.cold+0x3e4/0x94c [63010.947698] md_thread+0xab/0x160 [63010.951024] ? md_write_inc+0x50/0x50 [63010.954688] kthread+0x149/0x170 [63010.957923] ? set_kthread_struct+0x40/0x40 [63010.962107] ret_from_fork+0x22/0x30 Removing the code that sets mddev->private to NULL in raid0 can fix problem. Fixes: 0c031fd37f69 (md: Move alloc/free acct bioset in to personality) Reported-by: Fine Fan <ffan@redhat.com> Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0f2571ad7a30ff6b33cde142439f9378669f8b4f upstream.

In normal stop process, it does like this:
   do_md_stop
      |
   __md_stop (pers->free(); mddev->private=NULL)
      |
   md_free (free mddev)
__md_stop sets mddev->private to NULL after pers->free. The raid device
will be stopped and mddev memory is free. But in reshape, it doesn't
free the mddev and mddev will still be used in new raid.

In reshape, it first sets mddev->private to new_pers and then runs
old_pers->free(). Now raid0 sets mddev->private to NULL in raid0_free.
The new raid can't work anymore. It will panic when dereference
mddev->private because of NULL pointer dereference.

It can panic like this:
[63010.814972] kernel BUG at drivers/md/raid10.c:928!
[63010.819778] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[63010.825011] CPU: 3 PID: 44437 Comm: md0_resync Kdump: loaded Not tainted 5.14.0-86.el9.x86_64 #1
[63010.833789] Hardware name: Dell Inc. PowerEdge R6415/07YXFK, BIOS 1.15.0 09/11/2020
[63010.841440] RIP: 0010:raise_barrier+0x161/0x170 [raid10]
[63010.865508] RSP: 0018:ffffc312408bbc10 EFLAGS: 00010246
[63010.870734] RAX: 0000000000000000 RBX: ffffa00bf7d39800 RCX: 0000000000000000
[63010.877866] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffa00bf7d39800
[63010.884999] RBP: 0000000000000000 R08: fffffa4945e74400 R09: 0000000000000000
[63010.892132] R10: ffffa00eed02f798 R11: 0000000000000000 R12: ffffa00bbc435200
[63010.899266] R13: ffffa00bf7d39800 R14: 0000000000000400 R15: 0000000000000003
[63010.906399] FS:  0000000000000000(0000) GS:ffffa00eed000000(0000) knlGS:0000000000000000
[63010.914485] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[63010.920229] CR2: 00007f5cfbe99828 CR3: 0000000105efe000 CR4: 00000000003506e0
[63010.927363] Call Trace:
[63010.929822]  ? bio_reset+0xe/0x40
[63010.933144]  ? raid10_alloc_init_r10buf+0x60/0xa0 [raid10]
[63010.938629]  raid10_sync_request+0x756/0x1610 [raid10]
[63010.943770]  md_do_sync.cold+0x3e4/0x94c
[63010.947698]  md_thread+0xab/0x160
[63010.951024]  ? md_write_inc+0x50/0x50
[63010.954688]  kthread+0x149/0x170
[63010.957923]  ? set_kthread_struct+0x40/0x40
[63010.962107]  ret_from_fork+0x22/0x30

Removing the code that sets mddev->private to NULL in raid0 can fix
problem.

Fixes: 0c031fd37f69 (md: Move alloc/free acct bioset in to personality)
Reported-by: Fine Fan <ffan@redhat.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
md: Move alloc/free acct bioset in to personality 2022-01-27T10:05:08+00:00 Xiao Ni xni@redhat.com 2021-12-10T09:31:15+00:00 00e3d58f50a875343124bcf5a9637520a492b0d1 commit 0c031fd37f69deb0cd8c43bbfcfccd62ebd7e952 upstream. bioset acct is only needed for raid0 and raid5. Therefore, md_run only allocates it for raid0 and raid5. However, this does not cover personality takeover, which may cause uninitialized bioset. For example, the following repro steps: mdadm -CR /dev/md0 -l1 -n2 /dev/loop0 /dev/loop1 mdadm --wait /dev/md0 mkfs.xfs /dev/md0 mdadm /dev/md0 --grow -l5 mount /dev/md0 /mnt causes panic like: [ 225.933939] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 225.934903] #PF: supervisor instruction fetch in kernel mode [ 225.935639] #PF: error_code(0x0010) - not-present page [ 225.936361] PGD 0 P4D 0 [ 225.936677] Oops: 0010 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN PTI [ 225.937525] CPU: 27 PID: 1133 Comm: mount Not tainted 5.16.0-rc3+ #706 [ 225.938416] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.module_el8.4.0+547+a85d02ba 04/01/2014 [ 225.939922] RIP: 0010:0x0 [ 225.940289] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. [ 225.941196] RSP: 0018:ffff88815897eff0 EFLAGS: 00010246 [ 225.941897] RAX: 0000000000000000 RBX: 0000000000092800 RCX: ffffffff81370a39 [ 225.942813] RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000092800 [ 225.943772] RBP: 1ffff1102b12fe04 R08: fffffbfff0b43c01 R09: fffffbfff0b43c01 [ 225.944807] R10: ffffffff85a1e007 R11: fffffbfff0b43c00 R12: ffff88810eaaaf58 [ 225.945757] R13: 0000000000000000 R14: ffff88810eaaafb8 R15: ffff88815897f040 [ 225.946709] FS: 00007ff3f2505080(0000) GS:ffff888fb5e00000(0000) knlGS:0000000000000000 [ 225.947814] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 225.948556] CR2: ffffffffffffffd6 CR3: 000000015aa5a006 CR4: 0000000000370ee0 [ 225.949537] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 225.950455] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 225.951414] Call Trace: [ 225.951787] <TASK> [ 225.952120] mempool_alloc+0xe5/0x250 [ 225.952625] ? mempool_resize+0x370/0x370 [ 225.953187] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 225.953862] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 225.954464] ? sched_clock_cpu+0x15/0x120 [ 225.955019] ? find_held_lock+0xac/0xd0 [ 225.955564] bio_alloc_bioset+0x1ed/0x2a0 [ 225.956080] ? lock_downgrade+0x3a0/0x3a0 [ 225.956644] ? bvec_alloc+0xc0/0xc0 [ 225.957135] bio_clone_fast+0x19/0x80 [ 225.957651] raid5_make_request+0x1370/0x1b70 [ 225.958286] ? sched_clock_cpu+0x15/0x120 [ 225.958797] ? __lock_acquire+0x8b2/0x3510 [ 225.959339] ? raid5_get_active_stripe+0xce0/0xce0 [ 225.959986] ? lock_is_held_type+0xd8/0x130 [ 225.960528] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 225.961135] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 225.961703] ? sched_clock_cpu+0x15/0x120 [ 225.962232] ? lock_release+0x27a/0x6c0 [ 225.962746] ? do_wait_intr_irq+0x130/0x130 [ 225.963302] ? lock_downgrade+0x3a0/0x3a0 [ 225.963815] ? lock_release+0x6c0/0x6c0 [ 225.964348] md_handle_request+0x342/0x530 [ 225.964888] ? set_in_sync+0x170/0x170 [ 225.965397] ? blk_queue_split+0x133/0x150 [ 225.965988] ? __blk_queue_split+0x8b0/0x8b0 [ 225.966524] ? submit_bio_checks+0x3b2/0x9d0 [ 225.967069] md_submit_bio+0x127/0x1c0 [...] Fix this by moving alloc/free of acct bioset to pers->run and pers->free. While we are on this, properly handle md_integrity_register() error in raid0_run(). Fixes: daee2024715d (md: check level before create and exit io_acct_set) Cc: stable@vger.kernel.org Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0c031fd37f69deb0cd8c43bbfcfccd62ebd7e952 upstream.

bioset acct is only needed for raid0 and raid5. Therefore, md_run only
allocates it for raid0 and raid5. However, this does not cover
personality takeover, which may cause uninitialized bioset. For example,
the following repro steps:

  mdadm -CR /dev/md0 -l1 -n2 /dev/loop0 /dev/loop1
  mdadm --wait /dev/md0
  mkfs.xfs /dev/md0
  mdadm /dev/md0 --grow -l5
  mount /dev/md0 /mnt

causes panic like:

[  225.933939] BUG: kernel NULL pointer dereference, address: 0000000000000000
[  225.934903] #PF: supervisor instruction fetch in kernel mode
[  225.935639] #PF: error_code(0x0010) - not-present page
[  225.936361] PGD 0 P4D 0
[  225.936677] Oops: 0010 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN PTI
[  225.937525] CPU: 27 PID: 1133 Comm: mount Not tainted 5.16.0-rc3+ #706
[  225.938416] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.module_el8.4.0+547+a85d02ba 04/01/2014
[  225.939922] RIP: 0010:0x0
[  225.940289] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[  225.941196] RSP: 0018:ffff88815897eff0 EFLAGS: 00010246
[  225.941897] RAX: 0000000000000000 RBX: 0000000000092800 RCX: ffffffff81370a39
[  225.942813] RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000092800
[  225.943772] RBP: 1ffff1102b12fe04 R08: fffffbfff0b43c01 R09: fffffbfff0b43c01
[  225.944807] R10: ffffffff85a1e007 R11: fffffbfff0b43c00 R12: ffff88810eaaaf58
[  225.945757] R13: 0000000000000000 R14: ffff88810eaaafb8 R15: ffff88815897f040
[  225.946709] FS:  00007ff3f2505080(0000) GS:ffff888fb5e00000(0000) knlGS:0000000000000000
[  225.947814] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  225.948556] CR2: ffffffffffffffd6 CR3: 000000015aa5a006 CR4: 0000000000370ee0
[  225.949537] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  225.950455] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  225.951414] Call Trace:
[  225.951787]  <TASK>
[  225.952120]  mempool_alloc+0xe5/0x250
[  225.952625]  ? mempool_resize+0x370/0x370
[  225.953187]  ? rcu_read_lock_sched_held+0xa1/0xd0
[  225.953862]  ? rcu_read_lock_bh_held+0xb0/0xb0
[  225.954464]  ? sched_clock_cpu+0x15/0x120
[  225.955019]  ? find_held_lock+0xac/0xd0
[  225.955564]  bio_alloc_bioset+0x1ed/0x2a0
[  225.956080]  ? lock_downgrade+0x3a0/0x3a0
[  225.956644]  ? bvec_alloc+0xc0/0xc0
[  225.957135]  bio_clone_fast+0x19/0x80
[  225.957651]  raid5_make_request+0x1370/0x1b70
[  225.958286]  ? sched_clock_cpu+0x15/0x120
[  225.958797]  ? __lock_acquire+0x8b2/0x3510
[  225.959339]  ? raid5_get_active_stripe+0xce0/0xce0
[  225.959986]  ? lock_is_held_type+0xd8/0x130
[  225.960528]  ? rcu_read_lock_sched_held+0xa1/0xd0
[  225.961135]  ? rcu_read_lock_bh_held+0xb0/0xb0
[  225.961703]  ? sched_clock_cpu+0x15/0x120
[  225.962232]  ? lock_release+0x27a/0x6c0
[  225.962746]  ? do_wait_intr_irq+0x130/0x130
[  225.963302]  ? lock_downgrade+0x3a0/0x3a0
[  225.963815]  ? lock_release+0x6c0/0x6c0
[  225.964348]  md_handle_request+0x342/0x530
[  225.964888]  ? set_in_sync+0x170/0x170
[  225.965397]  ? blk_queue_split+0x133/0x150
[  225.965988]  ? __blk_queue_split+0x8b0/0x8b0
[  225.966524]  ? submit_bio_checks+0x3b2/0x9d0
[  225.967069]  md_submit_bio+0x127/0x1c0
[...]

Fix this by moving alloc/free of acct bioset to pers->run and pers->free.

While we are on this, properly handle md_integrity_register() error in
raid0_run().

Fixes: daee2024715d (md: check level before create and exit io_acct_set)
Cc: stable@vger.kernel.org
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
md: add io accounting for raid0 and raid5 2021-06-15T05:32:06+00:00 Guoqing Jiang jgq516@gmail.com 2021-05-25T09:46:17+00:00 10764815ff4728d2c57da677cd5d3dd6f446cf5f We introduce a new bioset (io_acct_set) for raid0 and raid5 since they don't own clone infrastructure to accounting io. And the bioset is added to mddev instead of to raid0 and raid5 layer, because with this way, we can put common functions to md.h and reuse them in raid0 and raid5. Also struct md_io_acct is added accordingly which includes io start_time, the origin bio and cloned bio. Then we can call bio_{start,end}_io_acct to get related io status. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org> 
We introduce a new bioset (io_acct_set) for raid0 and raid5 since they
don't own clone infrastructure to accounting io. And the bioset is added
to mddev instead of to raid0 and raid5 layer, because with this way, we
can put common functions to md.h and reuse them in raid0 and raid5.

Also struct md_io_acct is added accordingly which includes io start_time,
the origin bio and cloned bio. Then we can call bio_{start,end}_io_acct
to get related io status.

Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>