Add a new field async_depth to request_queue and related APIs, this is
currently not used, following patches will convert elevators to use
this instead of internal async_depth.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are no functional changes, just make code cleaner.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bfq and mq-deadline consider sync writes as async requests and only
reserve tags for sync reads by async_depth, however, kyber doesn't
consider sync writes as async requests for now.
Consider the case there are lots of dirty pages, and user use fsync to
flush dirty pages. In this case sched_tags can be exhausted by sync writes
and sync reads can stuck waiting for tag. Hence let kyber follow what
mq-deadline and bfq did, and unify async requests checking for all
elevators.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This value represents the number of requests for elevator tags, or drivers
tags if elevator is none. The max value for elevator tags is 2048, and
in drivers at most 16 bits is used for tag.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
0-day bot flagged the use of strcpy() in blk_trace_setup(), because the
source buffer can theoretically be bigger than the destination buffer.
While none of the current callers pass a string bigger than
BLKTRACE_BDEV_SIZE, use strscpy() to prevent eventual future misuse and
silence the checker warnings.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202602020718.GUEIRyG9-lkp@intel.com/
Fixes: 113cbd6282 ("blktrace: pass blk_user_trace2 to setup functions")
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Creating new debugfs entries can trigger fs reclaim, hence we can't do
this with queue frozen, meanwhile, other locks that can be held while
queue is frozen should not be held as well.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In blk_mq_update_nr_hw_queues(), debugfs_mutex is not held while
creating debugfs entries for hctxs. Hence add debugfs_mutex there,
it's safe because queue is not frozen.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Because this helper is only used by iocost and iolatency, while they
don't have debugfs entries.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Because it's only used inside blk-mq-debugfs.c now.
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently rq-qos debugfs entries are created from rq_qos_add(), while
rq_qos_add() can be called while queue is still frozen. This can
deadlock because creating new entries can trigger fs reclaim.
Fix this problem by delaying creating rq-qos debugfs entries after queue
is unfrozen.
- For wbt, 1) it can be initialized by default, fix it by calling new
helper after wbt_init() from wbt_init_enable_default(); 2) it can be
initialized by sysfs, fix it by calling new helper after queue is
unfrozen from wbt_set_lat().
- For iocost and iolatency, they can only be initialized by blkcg
configuration, however, they don't have debugfs entries for now, hence
they are not handled yet.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is already a helper blk_mq_debugfs_register_rqos() to register
one rqos, however this helper is called synchronously when the rqos is
created with queue frozen.
Prepare to fix possible deadlock to create blk-mq debugfs entries while
queue is still frozen.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If wbt is disabled by default and user configures wbt by sysfs, queue
will be frozen first and then pcpu_alloc_mutex will be held in
blk_stat_alloc_callback().
Fix this problem by allocating memory first before queue frozen.
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To move implementation details inside blk-wbt.c, prepare to fix possible
deadlock to call wbt_init() while queue is frozen in the next patch.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The locking ranges count and the array items are always ignored unless
Single User Mode (SUM) is requested in the activate method.
It is useless to enforce limits of unused array in the non-SUM case.
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull MD fixes from Yu Kuai:
"Bug Fixes:
- Fix return value of mddev_trylock (Xiao Ni)
- Fix memory leak in raid1_run() (Zilin Guan)
Maintainers:
- Add Li Nan as mdraid reviewer (Li Nan)"
* tag 'md-7.0-20260202' of git://git.kernel.org/pub/scm/linux/kernel/git/mdraid/linux:
MAINTAINERS: Add Li Nan as md/raid reviewer
md: fix return value of mddev_trylock
md/raid1: fix memory leak in raid1_run()
I've long contributed to and reviewed the md/raid subsystem. I've fixed
many bugs and done code refactors, with dozens of patches merged.
I now volunteer to work as a reviewer for this subsystem.
Link: https://lore.kernel.org/linux-raid/20260202083203.3017096-1-linan666@huaweicloud.com
Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
raid1_run() calls setup_conf() which registers a thread via
md_register_thread(). If raid1_set_limits() fails, the previously
registered thread is not unregistered, resulting in a memory leak
of the md_thread structure and the thread resource itself.
Add md_unregister_thread() to the error path to properly cleanup
the thread, which aligns with the error handling logic of other paths
in this function.
Compile tested only. Issue found using a prototype static analysis tool
and code review.
Link: https://lore.kernel.org/linux-raid/20260126071533.606263-1-zilin@seu.edu.cn
Fixes: 97894f7d3c ("md/raid1: use the atomic queue limit update APIs")
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Reviewed-by: Li Nan <linan122@huawei.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
Remove test_generic_01.sh since block layer may reorder I/O, making
the test prone to false positives. Apply the improvements to
test_generic_02.sh instead, which supposes for covering ublk dispatch
io order.
Rework test_generic_02 to verify that ublk dispatch doesn't reorder I/O
by comparing request start order with completion order using bpftrace.
The bpftrace script now:
- Tracks each request's start sequence number in a map keyed by sector
- On completion, verifies the request's start order matches expected
completion order
- Reports any out-of-order completions detected
The test script:
- Wait bpftrace BEGIN code block is run
- Pins fio to CPU 0 for deterministic behavior
- Uses block_io_start and block_rq_complete tracepoints
- Checks bpftrace output for reordering errors
Reported-and-tested-by: Alexander Atanasov <alex@zazolabs.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When running tests in parallel with high JOBS count (e.g., JOBS=64),
the existing timeouts can be insufficient due to system load:
- Increase state wait loops from 20/50 to 100 iterations in
_recover_ublk_dev(), __ublk_quiesce_dev(), and __ublk_kill_daemon()
to handle slower state transitions under heavy load
- Add --timeout=20 to udevadm settle calls to prevent indefinite
hangs when udev event queue is overwhelmed by rapid device
creation/deletion
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add _ublk_sleep() helper function that uses different sleep times
depending on whether tests run in parallel or sequential mode.
Usage: _ublk_sleep <normal_secs> <parallel_secs>
Export JOBS variable from Makefile so test scripts can detect parallel
execution, and use _ublk_sleep in test_part_02.sh to handle the
partition scan delay (1s normal, 5s parallel).
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add convenient Makefile targets for running specific test groups:
- run_generic, run_batch, run_null, run_loop, run_stripe, run_stress, etc.
- run_all for running all tests
Test groups are auto-detected from TEST_PROGS using pattern matching
(test_<group>_<num>.sh -> group), and targets are generated dynamically
using define/eval templates.
Supports parallel execution via JOBS variable:
- JOBS=1 (default): sequential with kselftest TAP output
- JOBS>1: parallel execution with xargs -P
Usage examples:
make run_null # Sequential execution
make run_stress JOBS=4 # Parallel with 4 jobs
make run_all JOBS=8 # Run all tests with 8 parallel jobs
With JOBS=8, running time of `make run_all` is reduced to 2m2s from 6m5s
in my test VM.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Track device IDs in UBLK_DEVS array when created. Update
_cleanup_test() to only delete devices created by this test
instead of using 'del -a' which removes all devices.
This prepares for running tests concurrently where each test
should only clean up its own devices.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add _ublk_del_dev() to delete a specific ublk device by ID and
use it in all test scripts instead of calling UBLK_PROG directly.
Also remove unused _remove_ublk_devices() function.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Encapsulate each test case in its own function for better organization
and maintainability:
- _setup_device(): device and backfile initialization
- _test_fill_and_verify(): initial data population
- _test_corrupted_reftag(): reftag corruption detection test
- _test_corrupted_data(): data corruption detection test
- _test_bad_apptag(): apptag mismatch detection test
Also fix temp file creation to use ${UBLK_TEST_DIR}/fio_err_XXXXX instead of
creating in current directory.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove intermediate TDIR variable and set UBLK_TEST_DIR directly
in _prep_test(). Remove default initialization since the directory
is created dynamically when tests run.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The struct ublk_io is in fact accessed in __ublk_complete_rq() after the
comment. But it's not racy to access the ublk_io between clearing its
UBLK_IO_FLAG_OWNED_BY_SRV flag and completing the request, as no other
thread can use the ublk_io in the meantime.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Create and use a temporary directory for the files created during
test runs. If TMPDIR environment variable is set use it as a base
for the temporary directory path.
TMPDIR=/mnt/scratch make run_tests
and
TMPDIR=/mnt/scratch ./test_generic_01.sh
will place test directory under /mnt/scratch
Signed-off-by: Alexander Atanasov <alex@zazolabs.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Log test start and end time in dmesg, so generated log messages
during the test run can be linked to specific test from the test
suite.
(switch to `date +%F %T`)
Signed-off-by: Alexander Atanasov <alex@zazolabs.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The null target doesn't handle IO, so disable partition scan to avoid IO
failures caused by integrity verification during the kernel's partition
table read.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Encapsulate each test case in its own function that creates the
device, runs checks, and deletes only that device. This avoids
calling _cleanup_test multiple times.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This test exercises partition scanning behavior, so move it to
the test_part_* group for consistency.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add test_part_01.sh to test the UBLK_F_NO_AUTO_PART_SCAN feature
flag which allows suppressing automatic partition scanning during
device startup while still allowing manual partition probing.
The test verifies:
- Normal behavior: partitions are auto-detected without the flag
- With flag: partitions are not auto-detected during START_DEV
- Manual scan: blockdev --rereadpt works with the flag
Also update kublk tool to support --no_auto_part_scan option and
recognize the feature flag.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add automatic TID derivation in test_common.sh based on the script
filename. The TID is extracted by stripping the "test_" prefix and
".sh" suffix from the script name (e.g., test_loop_01.sh -> loop_01).
This removes the need for each test script to manually define TID,
reducing boilerplate and preventing potential mismatches between
the script name and TID. Scripts can still override TID after
sourcing test_common.sh if needed.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a new feature flag UBLK_F_NO_AUTO_PART_SCAN to allow users to suppress
automatic partition scanning when starting a ublk device.
This is useful for some cases in which user don't want to scan
partitions.
Users still can manually trigger partition scanning later when appropriate
using standard tools (e.g., partprobe, blockdev --rereadpt).
Reported-by: Yoav Cohen <yoav@nvidia.com>
Link: https://lore.kernel.org/linux-block/DM4PR12MB63280C5637917C071C2F0D65A9A8A@DM4PR12MB6328.namprd12.prod.outlook.com/
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add !list_empty(&fcmd->node) check in ublk_batch_cancel_cmd() to ensure
the fcmd hasn't already been removed from the list. Once an fcmd is
removed from the list, it's considered claimed by whoever removed it
and will be freed by that path.
Meantime switch to list_del_init() for deleting it from list.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk_ctrl_start_recovery() only uses its const struct ublksrv_ctrl_cmd *
header argument to log the dev_id. But this value is already available
in struct ublk_device's ub_number field. So log ub_number instead and
drop the unused header argument.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
struct ublksrv_ctrl_cmd is part of the io_uring_sqe, which may lie in
userspace-mapped memory. It's racy to access its fields with normal
loads, as userspace may write to them concurrently. Use READ_ONCE() to
copy the ublksrv_ctrl_cmd from the io_uring_sqe to the stack. Use the
local copy in place of the one in the io_uring_sqe.
Fixes: 87213b0d84 ("ublk: allow non-blocking ctrl cmds in IO_URING_F_NONBLOCK issue")
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk_ctrl_cmd_dump() accesses (header *)sqe->cmd before
IO_URING_F_SQE128 flag check. This could cause out of boundary memory
access.
Move the SQE128 flag check earlier in ublk_ctrl_uring_cmd() to return
-EINVAL immediately if the flag is not set.
Fixes: 71f28f3136 ("ublk_drv: add io_uring based userspace block driver")
Signed-off-by: Govindarajulu Varadarajan <govind.varadar@gmail.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Introduce the helper function bdev_rot() to test if a block device is a
rotational one. The existing function bdev_nonrot() which tests for the
opposite condition is redefined using this new helper.
This avoids the double negation (operator and name) that appears when
testing if a block device is a rotational device, thus making the code a
little easier to read.
Call sites of bdev_nonrot() in the block layer are updated to use this
new helper. Remaining users in other subsystems are left unchanged for
now.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 1ceeedb597 ("ublk: optimize UBLK_IO_UNREGISTER_IO_BUF on daemon
task") optimized ublk request buffer unregistration to use a non-atomic
reference count decrement when performed on the ublk_io's daemon task.
The optimization applied to auto buffer unregistration, which happens as
part of handling UBLK_IO_COMMIT_AND_FETCH_REQ on the daemon task.
However, commit b749965edd ("ublk: remove ublk_commit_and_fetch()")
reordered the ublk_sub_req_ref() for the completed request before the
io_buffer_unregister_bvec() call. As a result, task_registered_buffers
is already 0 when io_buffer_unregister_bvec() calls ublk_io_release()
and the non-atomic refcount optimization doesn't apply.
Move the io_buffer_unregister_bvec() call back to before
ublk_need_complete_req() to restore the reference counting optimization.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: b749965edd ("ublk: remove ublk_commit_and_fetch()")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To check if a request queue is for a rotational device, a double
negation is needed with the pattern "!blk_queue_nonrot(q)". Simplify
this with the introduction of the helper blk_queue_rot() which tests
if a requests queue limit has the BLK_FEAT_ROTATIONAL feature set.
All call sites of blk_queue_nonrot() are modified to use blk_queue_rot()
and blk_queue_nonrot() definition removed.
No functional changes.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Unwrap the definition of BLK_FEAT_ATOMIC_WRITES and
renumber this feature to be sequential with BLK_FEAT_SKIP_TAGSET_QUIESCE.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add comprehensive documentation for ublk's split reference counting
model (io->ref + io->task_registered_buffers) above ublk_init_req_ref()
given this model isn't very straightforward.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace snprintf("%s", ...) with the faster and more direct strscpy().
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
During device unmapping (triggered by module unload or explicit unmap),
a refcount underflow occurs causing a use-after-free warning:
[14747.574913] ------------[ cut here ]------------
[14747.574916] refcount_t: underflow; use-after-free.
[14747.574917] WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x55/0x90, CPU#9: kworker/9:1/378
[14747.574924] Modules linked in: rnbd_client(-) rtrs_client rnbd_server rtrs_server rtrs_core ...
[14747.574998] CPU: 9 UID: 0 PID: 378 Comm: kworker/9:1 Tainted: G O N 6.19.0-rc3lblk-fnext+ #42 PREEMPT(voluntary)
[14747.575005] Workqueue: rnbd_clt_wq unmap_device_work [rnbd_client]
[14747.575010] RIP: 0010:refcount_warn_saturate+0x55/0x90
[14747.575037] Call Trace:
[14747.575038] <TASK>
[14747.575038] rnbd_clt_unmap_device+0x170/0x1d0 [rnbd_client]
[14747.575044] process_one_work+0x211/0x600
[14747.575052] worker_thread+0x184/0x330
[14747.575055] ? __pfx_worker_thread+0x10/0x10
[14747.575058] kthread+0x10d/0x250
[14747.575062] ? __pfx_kthread+0x10/0x10
[14747.575066] ret_from_fork+0x319/0x390
[14747.575069] ? __pfx_kthread+0x10/0x10
[14747.575072] ret_from_fork_asm+0x1a/0x30
[14747.575083] </TASK>
[14747.575096] ---[ end trace 0000000000000000 ]---
Befor this patch :-
The bug is a double kobject_put() on dev->kobj during device cleanup.
Kobject Lifecycle:
kobject_init_and_add() sets kobj.kref = 1 (initialization)
kobject_put() sets kobj.kref = 0 (should be called once)
* Before this patch:
rnbd_clt_unmap_device()
rnbd_destroy_sysfs()
kobject_del(&dev->kobj) [remove from sysfs]
kobject_put(&dev->kobj) PUT #1 (WRONG!)
kref: 1 to 0
rnbd_dev_release()
kfree(dev) [DEVICE FREED!]
rnbd_destroy_gen_disk() [use-after-free!]
rnbd_clt_put_dev()
refcount_dec_and_test(&dev->refcount)
kobject_put(&dev->kobj) PUT #2 (UNDERFLOW!)
kref: 0 to -1 [WARNING!]
The first kobject_put() in rnbd_destroy_sysfs() prematurely frees the
device via rnbd_dev_release(), then the second kobject_put() in
rnbd_clt_put_dev() causes refcount underflow.
* After this patch :-
Remove kobject_put() from rnbd_destroy_sysfs(). This function should
only remove sysfs visibility (kobject_del), not manage object lifetime.
Call Graph (FIXED):
rnbd_clt_unmap_device()
rnbd_destroy_sysfs()
kobject_del(&dev->kobj) [remove from sysfs only]
[kref unchanged: 1]
rnbd_destroy_gen_disk() [device still valid]
rnbd_clt_put_dev()
refcount_dec_and_test(&dev->refcount)
kobject_put(&dev->kobj) ONLY PUT (CORRECT!)
kref: 1 to 0 [BALANCED]
rnbd_dev_release()
kfree(dev) [CLEAN DESTRUCTION]
This follows the kernel pattern where sysfs removal (kobject_del) is
separate from object destruction (kobject_put).
Fixes: 581cf833ca ("block: rnbd: add .release to rnbd_dev_ktype")
Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
These imports are already in scope by importing `kernel::prelude::*` and
does not need to be imported separately.
Signed-off-by: Gary Guo <gary@garyguo.net>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull MD updates from Yu:
"Bug Fixes:
- Fix raid5_run() to return error when log_init() fails (Yu Kuai)
- Fix IO hang with degraded array with llbitmap (Yu Kuai)
- Fix percpu_ref not resurrected on suspend timeout in llbitmap
(Yu Kuai)
- Fix GPF in write_page caused by resize race (Jack Wang)
- Fix NULL pointer dereference in process_metadata_update
(Jiasheng Jiang)
- Fix hang when stopping arrays with metadata through dm-raid
(Heinz Mauelshagen)
- Fix any_working flag handling in raid10_sync_request (Li Nan)
Cleanups & Refactoring:
- Refactor sync/recovery code path, improve error handling for
badblocks, and remove unused recovery_disabled field (Li Nan)
- Consolidate mddev boolean fields into mddev_flags (Yu Kuai)
Improvements:
- Use mempool to allocate stripe_request_ctx and make sure max_sectors
is not less than io_opt in raid5 (Yu Kuai)"
* tag 'md-7.0-20260127' of git://git.kernel.org/pub/scm/linux/kernel/git/mdraid/linux: (23 commits)
md raid: fix hang when stopping arrays with metadata through dm-raid
md-cluster: fix NULL pointer dereference in process_metadata_update
md/bitmap: fix GPF in write_page caused by resize race
md/md-llbitmap: fix percpu_ref not resurrected on suspend timeout
md/raid5: fix IO hang with degraded array with llbitmap
md: remove recovery_disabled
md/raid10: cleanup skip handling in raid10_sync_request
md/raid10: fix any_working flag handling in raid10_sync_request
md: move finish_reshape to md_finish_sync()
md: factor out sync completion update into helper
md: remove MD_RECOVERY_ERROR handling and simplify resync_offset update
md: update curr_resync_completed even when MD_RECOVERY_INTR is set
md: mark rdev Faulty when badblocks setting fails
md: break remaining operations on badblocks set failure in narrow_write_error
md/raid1,raid10: support narrow_write_error when badblocks is disabled
md: factor error handling out of md_done_sync into helper
md/raid1: simplify uptodate handling in end_sync_write
md/raid5: make sure max_sectors is not less than io_opt
md/raid5: use mempool to allocate stripe_request_ctx
md: merge mddev serialize_policy into mddev_flags
...
There are no more callers of this function after commit f6b2d8b134
("btrfs: track the next file offset in struct btrfs_bio_ctrl"), so
remove the function.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
