This pull request goes with only a few sysctl moves from the
kernel/sysctl.c file, the rest of the work has been put towards
deprecating two API calls which incur recursion and prevent us
from simplifying the registration process / saving memory per
move. Most of the changes have been soaking on linux-next since
v6.3-rc3.
I've slowed down the kernel/sysctl.c moves due to Matthew Wilcox's
feedback that we should see if we could *save* memory with these
moves instead of incurring more memory. We currently incur more
memory since when we move a syctl from kernel/sysclt.c out to its
own file we end up having to add a new empty sysctl used to register
it. To achieve saving memory we want to allow syctls to be passed
without requiring the end element being empty, and just have our
registration process rely on ARRAY_SIZE(). Without this, supporting
both styles of sysctls would make the sysctl registration pretty
brittle, hard to read and maintain as can be seen from Meng Tang's
efforts to do just this [0]. Fortunately, in order to use ARRAY_SIZE()
for all sysctl registrations also implies doing the work to deprecate
two API calls which use recursion in order to support sysctl
declarations with subdirectories.
And so during this development cycle quite a bit of effort went into
this deprecation effort. I've annotated the following two APIs are
deprecated and in few kernel releases we should be good to remove them:
* register_sysctl_table()
* register_sysctl_paths()
During this merge window we should be able to deprecate and unexport
register_sysctl_paths(), we can probably do that towards the end
of this merge window.
Deprecating register_sysctl_table() will take a bit more time but
this pull request goes with a few example of how to do this.
As it turns out each of the conversions to move away from either of
these two API calls *also* saves memory. And so long term, all these
changes *will* prove to have saved a bit of memory on boot.
The way I see it then is if remove a user of one deprecated call, it
gives us enough savings to move one kernel/sysctl.c out from the
generic arrays as we end up with about the same amount of bytes.
Since deprecating register_sysctl_table() and register_sysctl_paths()
does not require maintainer coordination except the final unexport
you'll see quite a bit of these changes from other pull requests, I've
just kept the stragglers after rc3.
Most of these changes have been soaking on linux-next since around rc3.
[0] https://lkml.kernel.org/r/ZAD+cpbrqlc5vmry@bombadil.infradead.org
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Merge tag 'sysctl-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull sysctl updates from Luis Chamberlain:
"This only does a few sysctl moves from the kernel/sysctl.c file, the
rest of the work has been put towards deprecating two API calls which
incur recursion and prevent us from simplifying the registration
process / saving memory per move. Most of the changes have been
soaking on linux-next since v6.3-rc3.
I've slowed down the kernel/sysctl.c moves due to Matthew Wilcox's
feedback that we should see if we could *save* memory with these moves
instead of incurring more memory. We currently incur more memory since
when we move a syctl from kernel/sysclt.c out to its own file we end
up having to add a new empty sysctl used to register it. To achieve
saving memory we want to allow syctls to be passed without requiring
the end element being empty, and just have our registration process
rely on ARRAY_SIZE(). Without this, supporting both styles of sysctls
would make the sysctl registration pretty brittle, hard to read and
maintain as can be seen from Meng Tang's efforts to do just this [0].
Fortunately, in order to use ARRAY_SIZE() for all sysctl registrations
also implies doing the work to deprecate two API calls which use
recursion in order to support sysctl declarations with subdirectories.
And so during this development cycle quite a bit of effort went into
this deprecation effort. I've annotated the following two APIs are
deprecated and in few kernel releases we should be good to remove
them:
- register_sysctl_table()
- register_sysctl_paths()
During this merge window we should be able to deprecate and unexport
register_sysctl_paths(), we can probably do that towards the end of
this merge window.
Deprecating register_sysctl_table() will take a bit more time but this
pull request goes with a few example of how to do this.
As it turns out each of the conversions to move away from either of
these two API calls *also* saves memory. And so long term, all these
changes *will* prove to have saved a bit of memory on boot.
The way I see it then is if remove a user of one deprecated call, it
gives us enough savings to move one kernel/sysctl.c out from the
generic arrays as we end up with about the same amount of bytes.
Since deprecating register_sysctl_table() and register_sysctl_paths()
does not require maintainer coordination except the final unexport
you'll see quite a bit of these changes from other pull requests, I've
just kept the stragglers after rc3"
Link: https://lkml.kernel.org/r/ZAD+cpbrqlc5vmry@bombadil.infradead.org [0]
* tag 'sysctl-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (29 commits)
fs: fix sysctls.c built
mm: compaction: remove incorrect #ifdef checks
mm: compaction: move compaction sysctl to its own file
mm: memory-failure: Move memory failure sysctls to its own file
arm: simplify two-level sysctl registration for ctl_isa_vars
ia64: simplify one-level sysctl registration for kdump_ctl_table
utsname: simplify one-level sysctl registration for uts_kern_table
ntfs: simplfy one-level sysctl registration for ntfs_sysctls
coda: simplify one-level sysctl registration for coda_table
fs/cachefiles: simplify one-level sysctl registration for cachefiles_sysctls
xfs: simplify two-level sysctl registration for xfs_table
nfs: simplify two-level sysctl registration for nfs_cb_sysctls
nfs: simplify two-level sysctl registration for nfs4_cb_sysctls
lockd: simplify two-level sysctl registration for nlm_sysctls
proc_sysctl: enhance documentation
xen: simplify sysctl registration for balloon
md: simplify sysctl registration
hv: simplify sysctl registration
scsi: simplify sysctl registration with register_sysctl()
csky: simplify alignment sysctl registration
...
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Merge tag 'for-6.4/block-2023-04-21' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- drbd patches, bringing us closer to unifying the out-of-tree version
and the in tree one (Andreas, Christoph)
- support for auto-quiesce for the s390 dasd driver (Stefan)
- MD pull request via Song:
- md/bitmap: Optimal last page size (Jon Derrick)
- Various raid10 fixes (Yu Kuai, Li Nan)
- md: add error_handlers for raid0 and linear (Mariusz Tkaczyk)
- NVMe pull request via Christoph:
- Drop redundant pci_enable_pcie_error_reporting (Bjorn Helgaas)
- Validate nvmet module parameters (Chaitanya Kulkarni)
- Fence TCP socket on receive error (Chris Leech)
- Fix async event trace event (Keith Busch)
- Minor cleanups (Chaitanya Kulkarni, zhenwei pi)
- Fix and cleanup nvmet Identify handling (Damien Le Moal,
Christoph Hellwig)
- Fix double blk_mq_complete_request race in the timeout handler
(Lei Yin)
- Fix irq locking in nvme-fcloop (Ming Lei)
- Remove queue mapping helper for rdma devices (Sagi Grimberg)
- use structured request attribute checks for nbd (Jakub)
- fix blk-crypto race conditions between keyslot management (Eric)
- add sed-opal support for reading read locking range attributes
(Ondrej)
- make fault injection configurable for null_blk (Akinobu)
- clean up the request insertion API (Christoph)
- clean up the queue running API (Christoph)
- blkg config helper cleanups (Tejun)
- lazy init support for blk-iolatency (Tejun)
- various fixes and tweaks to ublk (Ming)
- remove hybrid polling. It hasn't really been useful since we got
async polled IO support, and these days we don't support sync polled
IO at all (Keith)
- misc fixes, cleanups, improvements (Zhong, Ondrej, Colin, Chengming,
Chaitanya, me)
* tag 'for-6.4/block-2023-04-21' of git://git.kernel.dk/linux: (118 commits)
nbd: fix incomplete validation of ioctl arg
ublk: don't return 0 in case of any failure
sed-opal: geometry feature reporting command
null_blk: Always check queue mode setting from configfs
block: ublk: switch to ioctl command encoding
blk-mq: fix the blk_mq_add_to_requeue_list call in blk_kick_flush
block, bfq: Fix division by zero error on zero wsum
fault-inject: fix build error when FAULT_INJECTION_CONFIGFS=y and CONFIGFS_FS=m
block: store bdev->bd_disk->fops->submit_bio state in bdev
block: re-arrange the struct block_device fields for better layout
md/raid5: remove unused working_disks variable
md/raid10: don't call bio_start_io_acct twice for bio which experienced read error
md/raid10: fix memleak of md thread
md/raid10: fix memleak for 'conf->bio_split'
md/raid10: fix leak of 'r10bio->remaining' for recovery
md/raid10: don't BUG_ON() in raise_barrier()
md: fix soft lockup in status_resync
md: add error_handlers for raid0 and linear
md: Use optimal I/O size for last bitmap page
md: Fix types in sb writer
...
status_resync() will calculate 'curr_resync - recovery_active' to show
user a progress bar like following:
[============>........] resync = 61.4%
'curr_resync' and 'recovery_active' is updated in md_do_sync(), and
status_resync() can read them concurrently, hence it's possible that
'curr_resync - recovery_active' can overflow to a huge number. In this
case status_resync() will be stuck in the loop to print a large amount
of '=', which will end up soft lockup.
Fix the problem by setting 'resync' to MD_RESYNC_ACTIVE in this case,
this way resync in progress will be reported to user.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230310073855.1337560-3-yukuai1@huaweicloud.com
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
Since commit ee6d3dd4ed ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.
Take advantage of this to constify the structure definitions to prevent
modification at runtime.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230214-kobj_type-md-v1-1-d6853f707f11@weissschuh.net
register_sysctl_table() is a deprecated compatibility wrapper.
register_sysctl() can do the directory creation for you so just use
that.
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Commit 3e45352259 ("md: Free resources in __md_stop") tried to fix
null-ptr-deference for 'active_io' by moving percpu_ref_exit() to
__md_stop(), however, the commit also moving 'writes_pending' to
__md_stop(), and this will cause mdadm tests broken:
BUG: kernel NULL pointer dereference, address: 0000000000000038
Oops: 0000 [#1] PREEMPT SMP
CPU: 15 PID: 17830 Comm: mdadm Not tainted 6.3.0-rc3-next-20230324-00009-g520d37
RIP: 0010:free_percpu+0x465/0x670
Call Trace:
<TASK>
__percpu_ref_exit+0x48/0x70
percpu_ref_exit+0x1a/0x90
__md_stop+0xe9/0x170
do_md_stop+0x1e1/0x7b0
md_ioctl+0x90c/0x1aa0
blkdev_ioctl+0x19b/0x400
vfs_ioctl+0x20/0x50
__x64_sys_ioctl+0xba/0xe0
do_syscall_64+0x6c/0xe0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
And the problem can be reporduced 100% by following test:
mdadm -CR /dev/md0 -l1 -n1 /dev/sda --force
echo inactive > /sys/block/md0/md/array_state
echo read-auto > /sys/block/md0/md/array_state
echo inactive > /sys/block/md0/md/array_state
Root cause:
// start raid
raid1_run
mddev_init_writes_pending
percpu_ref_init
// inactive raid
array_state_store
do_md_stop
__md_stop
percpu_ref_exit
// start raid again
array_state_store
do_md_run
raid1_run
mddev_init_writes_pending
if (mddev->writes_pending.percpu_count_ptr)
// won't reinit
// inactive raid again
...
percpu_ref_exit
-> null-ptr-deference
Before the commit, 'writes_pending' is exited when mddev is freed, and
it's safe to restart raid because mddev_init_writes_pending() already make
sure that 'writes_pending' will only be initialized once.
Fix the prblem by moving 'writes_pending' back, it's a litter hard to find
the relationship between alloc memory and free memory, however, code
changes is much less and we lived with this for a long time already.
Fixes: 3e45352259 ("md: Free resources in __md_stop")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230328094400.1448955-1-yukuai1@huaweicloud.com
slot_store() uses kstrtouint() to get a slot number, but stores the
result in an "int" variable (by casting a pointer).
This can result in a negative slot number if the unsigned int value is
very large.
A negative number means that the slot is empty, but setting a negative
slot number this way will not remove the device from the array. I don't
think this is a serious problem, but it could cause confusion and it is
best to fix it.
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
If md_run() fails after ->active_io is initialized, then percpu_ref_exit
is called in error path. However, later md_free_disk will call
percpu_ref_exit again which leads to a panic because of null pointer
dereference. It can also trigger this bug when resources are initialized
but are freed in error path, then will be freed again in md_free_disk.
BUG: kernel NULL pointer dereference, address: 0000000000000038
Oops: 0000 [#1] PREEMPT SMP
Workqueue: md_misc mddev_delayed_delete
RIP: 0010:free_percpu+0x110/0x630
Call Trace:
<TASK>
__percpu_ref_exit+0x44/0x70
percpu_ref_exit+0x16/0x90
md_free_disk+0x2f/0x80
disk_release+0x101/0x180
device_release+0x84/0x110
kobject_put+0x12a/0x380
kobject_put+0x160/0x380
mddev_delayed_delete+0x19/0x30
process_one_work+0x269/0x680
worker_thread+0x266/0x640
kthread+0x151/0x1b0
ret_from_fork+0x1f/0x30
For creating raid device, md raid calls do_md_run->md_run, dm raid calls
md_run. We alloc those memory in md_run. For stopping raid device, md raid
calls do_md_stop->__md_stop, dm raid calls md_stop->__md_stop. So we can
free those memory resources in __md_stop.
Fixes: 72adae23a7 ("md: Change active_io to percpu")
Reported-and-tested-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
io_acct_set was enabled for raid0/raid5 io accounting. bios that contain
md_io_acct are allocated in the i/o path. There isn't a good method to
monitor if these bios are all finished and freed. In the takeover process,
io_acct_set (which is used for bios with md_io_acct) need to be freed.
However, if some bios finish after io_acct_set is freed, it may trigger
the following panic:
[ 6973.767999] RIP: 0010:mempool_free+0x52/0x80
[ 6973.786098] Call Trace:
[ 6973.786549] md_end_io_acct+0x31/0x40
[ 6973.787227] blk_update_request+0x224/0x380
[ 6973.787994] blk_mq_end_request+0x1a/0x130
[ 6973.788739] blk_complete_reqs+0x35/0x50
[ 6973.789456] __do_softirq+0xd7/0x2c8
[ 6973.790114] ? sort_range+0x20/0x20
[ 6973.790763] run_ksoftirqd+0x2a/0x40
[ 6973.791400] smpboot_thread_fn+0xb5/0x150
[ 6973.792114] kthread+0x10b/0x130
[ 6973.792724] ? set_kthread_struct+0x50/0x50
[ 6973.793491] ret_from_fork+0x1f/0x40
Fix this by increasing and decreasing active_io for each bio with
md_io_acct so that mddev_suspend() will wait until all bios from
io_acct_set finish before freeing io_acct_set.
Reported-by: Fine Fan <ffan@redhat.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Just replace magic numbers by MD_RESYNC_* enumerations.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
dm raid calls md_stop to stop the raid device. It needs to
free the writes_pending here.
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Now the type of active_io is atomic. It's used to count how many ios are
in the submitting process and it's added and decreased very time. But it
only needs to check if it's zero when suspending the raid. So we can
switch atomic to percpu to improve the performance.
After switching active_io to percpu type, we use the state of active_io
to judge if the raid device is suspended. And we don't need to wake up
->sb_wait in md_handle_request anymore. It's done in the callback function
which is registered when initing active_io. The argument mddev->suspended
is only used to count how many users are trying to set raid to suspend
state.
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
This helper function will be used in next patch. It's easy for
understanding.
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Don't update recovery_cp when curr_resync is MD_RESYNC_ACTIVE, otherwise
md may skip the resync of the first 3 sectors if the resync procedure is
interrupted before the first calling of ->sync_request() as shown below:
md_do_sync thread control thread
// setup resync
mddev->recovery_cp = 0
j = 0
mddev->curr_resync = MD_RESYNC_ACTIVE
// e.g., set array as idle
set_bit(MD_RECOVERY_INTR, &&mddev_recovery)
// resync loop
// check INTR before calling sync_request
!test_bit(MD_RECOVERY_INTR, &mddev->recovery
// resync interrupted
// update recovery_cp from 0 to 3
// the resync of three 3 sectors will be skipped
mddev->recovery_cp = 3
Fixes: eac58d08d4 ("md: Use enum for overloaded magic numbers used by mddev->curr_resync")
Cc: stable@vger.kernel.org # 6.0+
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Commit fb541ca4c3 ("md: remove lock_bdev / unlock_bdev") removes
wrappers for blkdev_get/blkdev_put. However, the uninitialized local
static variable of pointer type 'claim_rdev' in md_import_device()
is NULL, which leads to the following warning call trace:
WARNING: CPU: 22 PID: 1037 at block/bdev.c:577 bd_prepare_to_claim+0x131/0x150
CPU: 22 PID: 1037 Comm: mdadm Not tainted 6.2.0-rc3+ #69
..
RIP: 0010:bd_prepare_to_claim+0x131/0x150
..
Call Trace:
<TASK>
? _raw_spin_unlock+0x15/0x30
? iput+0x6a/0x220
blkdev_get_by_dev.part.0+0x4b/0x300
md_import_device+0x126/0x1d0
new_dev_store+0x184/0x240
md_attr_store+0x80/0xf0
kernfs_fop_write_iter+0x128/0x1c0
vfs_write+0x2be/0x3c0
ksys_write+0x5f/0xe0
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
It turns out the md device cannot be used:
md: could not open device unknown-block(259,0).
md: md127 stopped.
Fix the issue by declaring the local static variable of struct type
and passing the pointer of the variable to blkdev_get_by_dev().
Fixes: fb541ca4c3 ("md: remove lock_bdev / unlock_bdev")
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
This can't happen right now, but in preparation for allowing
bio_split_to_limits() returning NULL if it ended the bio, check for it
in all the callers.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
unbind_rdev_from_array is only called from md_kick_rdev_from_array, so
merge it into its only caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
md_kick_rdev_from_array is only used in md.c, so unexport it and mark
the symbol static.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
These wrappers for blkdev_get / blkdev_put just horribly confuse the
code with their odd naming. Remove them and improve the error unwinding
in md_import_device with the now folded code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
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Merge tag 'for-6.1/block-2022-10-03' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- NVMe pull requests via Christoph:
- handle number of queue changes in the TCP and RDMA drivers
(Daniel Wagner)
- allow changing the number of queues in nvmet (Daniel Wagner)
- also consider host_iface when checking ip options (Daniel
Wagner)
- don't map pages which can't come from HIGHMEM (Fabio M. De
Francesco)
- avoid unnecessary flush bios in nvmet (Guixin Liu)
- shrink and better pack the nvme_iod structure (Keith Busch)
- add comment for unaligned "fake" nqn (Linjun Bao)
- print actual source IP address through sysfs "address" attr
(Martin Belanger)
- various cleanups (Jackie Liu, Wolfram Sang, Genjian Zhang)
- handle effects after freeing the request (Keith Busch)
- copy firmware_rev on each init (Keith Busch)
- restrict management ioctls to admin (Keith Busch)
- ensure subsystem reset is single threaded (Keith Busch)
- report the actual number of tagset maps in nvme-pci (Keith
Busch)
- small fabrics authentication fixups (Christoph Hellwig)
- add common code for tagset allocation and freeing (Christoph
Hellwig)
- stop using the request_queue in nvmet (Christoph Hellwig)
- set min_align_mask before calculating max_hw_sectors (Rishabh
Bhatnagar)
- send a rediscover uevent when a persistent discovery controller
reconnects (Sagi Grimberg)
- misc nvmet-tcp fixes (Varun Prakash, zhenwei pi)
- MD pull request via Song:
- Various raid5 fix and clean up, by Logan Gunthorpe and David
Sloan.
- Raid10 performance optimization, by Yu Kuai.
- sbitmap wakeup hang fixes (Hugh, Keith, Jan, Yu)
- IO scheduler switching quisce fix (Keith)
- s390/dasd block driver updates (Stefan)
- support for recovery for the ublk driver (ZiyangZhang)
- rnbd drivers fixes and updates (Guoqing, Santosh, ye, Christoph)
- blk-mq and null_blk map fixes (Bart)
- various bcache fixes (Coly, Jilin, Jules)
- nbd signal hang fix (Shigeru)
- block writeback throttling fix (Yu)
- optimize the passthrough mapping handling (me)
- prepare block cgroups to being gendisk based (Christoph)
- get rid of an old PSI hack in the block layer, moving it to the
callers instead where it belongs (Christoph)
- blk-throttle fixes and cleanups (Yu)
- misc fixes and cleanups (Liu Shixin, Liu Song, Miaohe, Pankaj,
Ping-Xiang, Wolfram, Saurabh, Li Jinlin, Li Lei, Lin, Li zeming,
Miaohe, Bart, Coly, Gaosheng
* tag 'for-6.1/block-2022-10-03' of git://git.kernel.dk/linux: (162 commits)
sbitmap: fix lockup while swapping
block: add rationale for not using blk_mq_plug() when applicable
block: adapt blk_mq_plug() to not plug for writes that require a zone lock
s390/dasd: use blk_mq_alloc_disk
blk-cgroup: don't update the blkg lookup hint in blkg_conf_prep
nvmet: don't look at the request_queue in nvmet_bdev_set_limits
nvmet: don't look at the request_queue in nvmet_bdev_zone_mgmt_emulate_all
blk-mq: use quiesced elevator switch when reinitializing queues
block: replace blk_queue_nowait with bdev_nowait
nvme: remove nvme_ctrl_init_connect_q
nvme-loop: use the tagset alloc/free helpers
nvme-loop: store the generic nvme_ctrl in set->driver_data
nvme-loop: initialize sqsize later
nvme-fc: use the tagset alloc/free helpers
nvme-fc: store the generic nvme_ctrl in set->driver_data
nvme-fc: keep ctrl->sqsize in sync with opts->queue_size
nvme-rdma: use the tagset alloc/free helpers
nvme-rdma: store the generic nvme_ctrl in set->driver_data
nvme-tcp: use the tagset alloc/free helpers
nvme-tcp: store the generic nvme_ctrl in set->driver_data
...
Replace blk_queue_nowait with a bdev_nowait helpers that takes the
block_device given that the I/O submission path should not have to
look into the request_queue.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Link: https://lore.kernel.org/r/20220927075815.269694-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A regression is seen where mddev devices stay permanently after they
are stopped due to an elevated reference count.
This was tracked down to an extra mddev_get() in md_seq_start().
It only happened rarely because most of the time the md_seq_start()
is called with a zero offset. The path with an extra mddev_get() only
happens when it starts with a non-zero offset.
The commit noted below changed an mddev_get() to check its success
but inadvertently left the original call in. Remove the extra call.
Fixes: 12a6caf273 ("md: only delete entries from all_mddevs when the disk is freed")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Guoqing Jiang <Guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
A race condition still exists when removing and re-creating md devices
in test cases. However, it is only seen on some setups.
The race condition was tracked down to a reference still being held
to the kobject by the rdev in the md_rdev_misc_wq which will be released
in rdev_delayed_delete().
md_alloc() waits for previous deletions by waiting on the md_misc_wq,
but the md_rdev_misc_wq may still be holding a reference to a recently
removed device.
To fix this, also flush the md_rdev_misc_wq in md_alloc().
Signed-off-by: David Sloan <david.sloan@eideticom.com>
[logang@deltatee.com: rewrote commit message]
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
The double indirect bio leads to somewhat suboptimal code generation.
Instead return the (original or split) bio, and make sure the
request_queue arguments to the lower level helpers is passed after the
bio to avoid constant reshuffling of the argument passing registers.
Also give it and the helpers used to implement it more descriptive names.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220727162300.3089193-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When we ran the lvm test "shell/integrity-blocksize-3.sh" on a kernel with
kasan, we got failure in write_page.
The reason for the failure is that md_bitmap_destroy is called before
destroying the thread and the thread may be waiting in the function
write_page for the bio to complete. When the thread finishes waiting, it
executes "if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))", which
triggers the kasan warning.
Note that the commit 48df498daf that caused this bug claims that it is
neede for md-cluster, you should check md-cluster and possibly find
another bugfix for it.
BUG: KASAN: use-after-free in write_page+0x18d/0x680 [md_mod]
Read of size 8 at addr ffff889162030c78 by task mdX_raid1/5539
CPU: 10 PID: 5539 Comm: mdX_raid1 Not tainted 5.19.0-rc2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x34/0x44
print_report.cold+0x45/0x57a
? __lock_text_start+0x18/0x18
? write_page+0x18d/0x680 [md_mod]
kasan_report+0xa8/0xe0
? write_page+0x18d/0x680 [md_mod]
kasan_check_range+0x13f/0x180
write_page+0x18d/0x680 [md_mod]
? super_sync+0x4d5/0x560 [dm_raid]
? md_bitmap_file_kick+0xa0/0xa0 [md_mod]
? rs_set_dev_and_array_sectors+0x2e0/0x2e0 [dm_raid]
? mutex_trylock+0x120/0x120
? preempt_count_add+0x6b/0xc0
? preempt_count_sub+0xf/0xc0
md_update_sb+0x707/0xe40 [md_mod]
md_reap_sync_thread+0x1b2/0x4a0 [md_mod]
md_check_recovery+0x533/0x960 [md_mod]
raid1d+0xc8/0x2a20 [raid1]
? var_wake_function+0xe0/0xe0
? psi_group_change+0x411/0x500
? preempt_count_sub+0xf/0xc0
? _raw_spin_lock_irqsave+0x78/0xc0
? __lock_text_start+0x18/0x18
? raid1_end_read_request+0x2a0/0x2a0 [raid1]
? preempt_count_sub+0xf/0xc0
? _raw_spin_unlock_irqrestore+0x19/0x40
? del_timer_sync+0xa9/0x100
? try_to_del_timer_sync+0xc0/0xc0
? _raw_spin_lock_irqsave+0x78/0xc0
? __lock_text_start+0x18/0x18
? __list_del_entry_valid+0x68/0xa0
? finish_wait+0xa3/0x100
md_thread+0x161/0x260 [md_mod]
? unregister_md_personality+0xa0/0xa0 [md_mod]
? _raw_spin_lock_irqsave+0x78/0xc0
? prepare_to_wait_event+0x2c0/0x2c0
? unregister_md_personality+0xa0/0xa0 [md_mod]
kthread+0x148/0x180
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
</TASK>
Allocated by task 5522:
kasan_save_stack+0x1e/0x40
__kasan_kmalloc+0x80/0xa0
md_bitmap_create+0xa8/0xe80 [md_mod]
md_run+0x777/0x1300 [md_mod]
raid_ctr+0x249c/0x4a30 [dm_raid]
dm_table_add_target+0x2b0/0x620 [dm_mod]
table_load+0x1c8/0x400 [dm_mod]
ctl_ioctl+0x29e/0x560 [dm_mod]
dm_compat_ctl_ioctl+0x7/0x20 [dm_mod]
__do_compat_sys_ioctl+0xfa/0x160
do_syscall_64+0x90/0xc0
entry_SYSCALL_64_after_hwframe+0x46/0xb0
Freed by task 5680:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x40
kasan_set_free_info+0x20/0x40
__kasan_slab_free+0xf7/0x140
kfree+0x80/0x240
md_bitmap_free+0x1c3/0x280 [md_mod]
__md_stop+0x21/0x120 [md_mod]
md_stop+0x9/0x40 [md_mod]
raid_dtr+0x1b/0x40 [dm_raid]
dm_table_destroy+0x98/0x1e0 [dm_mod]
__dm_destroy+0x199/0x360 [dm_mod]
dev_remove+0x10c/0x160 [dm_mod]
ctl_ioctl+0x29e/0x560 [dm_mod]
dm_compat_ctl_ioctl+0x7/0x20 [dm_mod]
__do_compat_sys_ioctl+0xfa/0x160
do_syscall_64+0x90/0xc0
entry_SYSCALL_64_after_hwframe+0x46/0xb0
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 48df498daf ("md: move bitmap_destroy to the beginning of __md_stop")
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Two callers of md_alloc want to use the newly allocated devices, so
return it instead of letting them find it cumbersomely after the
allocation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-and-tested-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
autorun_devices should not be limited to the controls for the legacy
probe on open, so just call md_alloc directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-and-tested-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Eliminate the following coccicheck warning:
./drivers/md/md.c:8208:2-3: Unneeded semicolon
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After merging the block tree, today's linux-next build (x86_64
allmodconfig) failed like this:
drivers/md/md.c:717:22: error: 'mddev_find' defined but not used [-Werror=unused-function]
717 | static struct mddev *mddev_find(dev_t unit)
| ^~~~~~~~~~
cc1: all warnings being treated as errors
Caused by commit
4500d5c17910 ("md: simplify md_open")
Make mddev_find() available only for non-modular builds.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220721131132.070be166@canb.auug.org.au
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that devices are on the all_mddevs list until the gendisk is freed,
there can't be any duplicates. Remove the global list lookup and just
grab a reference.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This ensures device names don't get prematurely reused. Instead add a
deleted flag to skip already deleted devices in mddev_get and other
places that only want to see live mddevs.
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just do a simple list_for_each_entry_safe on all_mddevs, and only grab a
reference when we drop the lock and delete the now unused for_each_mddev
macro.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just do a simple list_for_each_entry_safe on all_mddevs, and only grab a
reference when we drop the lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just do a plain list_for_each that only grabs a mddev reference in
the case where the thread sleeps and restarts the list iteration.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This splits the code into nicely readable chunks and also avoids
the refcount inc/dec manipulations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The md_free name is rather misleading, so pick a better one.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Ensure that all private data is only freed once all accesses are done.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Error handling in md_alloc is a mess. Untangle it to just free the mddev
directly before add_disk is called and thus the gendisk is globally
visible. After that clear the hold flag and let the mddev_put take care
of cleaning up the mddev through the usual mechanisms.
Fixes: 5e55e2f5fc ("[PATCH] md: convert compile time warnings into runtime warnings")
Fixes: 9be68dd7ac ("md: add error handling support for add_disk()")
Fixes: 7ad1069166 ("md: properly unwind when failing to add the kobject in md_alloc")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Once a kobject is initialized, the containing object should not be
directly freed. So delay initialization until it is added. Also
remove the kobject_del call as the last put will remove the kobject as
well. The explicitly delete isn't needed here, and dropping it will
simplify further fixes.
With this md_free now does not need to check that ->gendisk is non-NULL
as it is always set by the time that kobject_init is called on
mddev->kobj.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since the bug which commit 8b48ec23cc ("md: don't unregister sync_thread
with reconfig_mutex held") fixed is related with action_store path, other
callers which reap sync_thread didn't need to be changed.
Let's pull md_unregister_thread from md_reap_sync_thread, then fix previous
bug with belows.
1. unlock mddev before md_reap_sync_thread in action_store.
2. save reshape_position before unlock, then restore it to ensure position
not changed accidentally by others.
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Boot-time assembly of arrays with md= command-line arguments breaks when
CONFIG_BLOCK_LEGACY_AUTOLOAD is unset. md_setup_drive() in md-autodetect.c
calls blkdev_get_by_dev(), assuming this implicitly creates the block
device.
Fix this by attempting to md_alloc() the array first. As in the probe path,
ignore any error as failure is caught by blkdev_get_by_dev() anyway.
Signed-off-by: Chris Webb <chris@arachsys.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The mdadm test 07layouts randomly produces a kernel hung task deadlock.
The deadlock is caused by the suspend_lo/suspend_hi files being set by
the mdadm background process during reshape and not being cleared
because the process hangs. (Leaving aside the issue of the fragility of
freezing kernel tasks by buggy userspace processes...)
When the background mdadm process hangs it, is waiting (without a
timeout) on a change to the sync_completed file signalling that the
reshape has completed. The process is woken up a couple times when
the reshape finishes but it is woken up before MD_RECOVERY_RUNNING
is cleared so sync_completed_show() reports 0 instead of "none".
To fix this, notify the sysfs file in md_reap_sync_thread() after
MD_RECOVERY_RUNNING has been cleared. This wakes up mdadm and causes
it to continue and write to suspend_lo/suspend_hi to allow IO to
continue.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The 07layouts test in mdadm fails on some systems. The failure
presents itself as the backup file not being removed before the next
layout is grown into:
mdadm: /dev/md0: cannot create backup file /tmp/md-test-backup:
File exists
This is because the background mdadm process, which is responsible for
cleaning up this backup file gets into an infinite loop waiting for
the reshape to start. mdadm checks the mdstat file if a reshape is
going and, if it is not, it waits for an event on the file or times
out in 5 seconds. On faster machines, the reshape may complete before
the 5 seconds times out, and thus the background mdadm process loops
waiting for a reshape to start that has already occurred.
mdadm reads the mdstat file to start, but mdstat does not report that the
reshape has begun, even though it has indeed begun. So the mdstat_wait()
call (in mdadm) which polls on the mdstat file won't ever return until
timing out.
The reason mdstat reports the reshape has started is due to an issue
in status_resync(). recovery_active is subtracted from curr_resync which
will result in a value of zero for the first chunk of reshaped data, and
the resulting read will report no reshape in progress.
To fix this, if "resync - recovery_active" is an overloaded value, force
the value to be MD_RESYNC_ACTIVE so the code reports a resync in progress.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Comments in the code document special values used for
mddev->curr_resync. Make this clearer by using an enum to label these
values.
The only functional change is a couple places use the wrong comparison
operator that implied 3 is another special value. They are all
fixed to imply that 3 or greater is an active resync.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>