linux-toradex.git/drivers/block, branch v6.17-rc6

ublk: avoid ublk_io_release() called after ublk char dev is closed

2025-08-28T13:56:57+00:00

When running test_stress_04.sh, the following warning is triggered:

WARNING: CPU: 1 PID: 135 at drivers/block/ublk_drv.c:1933 ublk_ch_release+0x423/0x4b0 [ublk_drv]

This happens when the daemon is abruptly killed:

- some references may still be held, because registering IO buffer
doesn't grab ublk char device reference

OR

- io->task_registered_buffers won't be cleared because io buffer is
released from non-daemon context

For zero-copy and auto buffer register modes, I/O reference crosses
syscalls, so IO reference may not be dropped naturally when ublk server is
killed abruptly. However, when releasing io_uring context, it is guaranteed
that the reference is dropped finally, see io_sqe_buffers_unregister() from
io_ring_ctx_free().

Fix this by adding ublk_drain_io_references() that:
- Waits for active I/O references dropped in async way by scheduling
  work function, for avoiding ublk dev and io_uring file's release
  dependency
- Reinitializes io->ref and io->task_registered_buffers to clean state

This ensures the reference count state is clean when ublk_queue_reinit()
is called, preventing the warning and potential use-after-free.

Fixes: 1f6540e2aabb ("ublk: zc register/unregister bvec")
Fixes: 1ceeedb59749 ("ublk: optimize UBLK_IO_UNREGISTER_IO_BUF on daemon task")
Fixes: 8a8fe42d765b ("ublk: optimize UBLK_IO_REGISTER_IO_BUF on daemon task")
Signed-off-by: Ming Lei 
Link: https://lore.kernel.org/r/20250827121602.2619736-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe

loop: fix zero sized loop for block special file

2025-08-25T13:46:57+00:00

By default, /dev/sda is block special file from devtmpfs, getattr will
return file size as zero, causing loop failed for raw block device.

We can add bdev_statx() to return device size, however this may
introduce changes that are not acknowledged by user. Fix this problem by
reverting changes for block special file, file mapping host is set to
bdev inode while opening, and use i_size_read() directly to get device
size.

Fixes: 47b71abd5846 ("loop: use vfs_getattr_nosec for accurate file size")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-lkp/202508200409.b2459c02-lkp@intel.com
Signed-off-by: Yu Kuai 
Reviewed-by: Ming Lei 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20250825093205.3684121-1-yukuai1@huaweicloud.com
[axboe: fix spelling error]
Signed-off-by: Jens Axboe

loop: use vfs_getattr_nosec for accurate file size

2025-08-18T19:10:35+00:00

Use vfs_getattr_nosec() in lo_calculate_size() for getting the file
size, rather than just read the cached inode size via i_size_read().
This provides better results than cached inode data, particularly for
network filesystems where metadata may be stale.

Signed-off-by: Rajeev Mishra 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20250818184821.115033-3-rajeevm@hpe.com
[axboe: massage commit message]
Signed-off-by: Jens Axboe

loop: Consolidate size calculation logic into lo_calculate_size()

2025-08-18T19:10:25+00:00

Renamed get_size to lo_calculate_size and merged the logic from get_size
and get_loop_size into a single function. Update all callers to use
lo_calculate_size. This is done in preparation for improving the size
detection logic.

Signed-off-by: Rajeev Mishra 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20250818184821.115033-2-rajeevm@hpe.com
[axboe: massage commit message]
Signed-off-by: Jens Axboe

ublk: check for unprivileged daemon on each I/O fetch

2025-08-11T13:57:48+00:00

Commit ab03a61c6614 ("ublk: have a per-io daemon instead of a per-queue
daemon") allowed each ublk I/O to have an independent daemon task.
However, nr_privileged_daemon is only computed based on whether the last
I/O fetched in each ublk queue has an unprivileged daemon task.
Fix this by checking whether every fetched I/O's daemon is privileged.
Change nr_privileged_daemon from a count of queues to a boolean
indicating whether any I/Os have an unprivileged daemon.

Signed-off-by: Caleb Sander Mateos 
Fixes: ab03a61c6614 ("ublk: have a per-io daemon instead of a per-queue daemon")
Reviewed-by: Ming Lei 
Link: https://lore.kernel.org/r/20250808155216.296170-1-csander@purestorage.com
Signed-off-by: Jens Axboe

ublk: don't quiesce in ublk_ch_release

2025-08-11T13:57:37+00:00

ublk_ch_release currently quiesces the device's request_queue while
setting force_abort/fail_io.  This avoids data races by preventing
concurrent reads from the I/O path, but is not strictly needed - at this
point, canceling is already set and guaranteed to be observed by any
concurrently executing I/Os, so they will be handled properly even if
the changes to force_abort/fail_io propagate to the I/O path later.
Remove the quiesce/unquiesce calls from ublk_ch_release. This makes the
writes to force_abort/fail_io concurrent with the reads in the I/O path,
so make the accesses atomic.

Before this change, the call to blk_mq_quiesce_queue was responsible for
most (90%) of the runtime of ublk_ch_release. With that call eliminated,
ublk_ch_release runs much faster. Here is a comparison of the total time
spent in calls to ublk_ch_release when a server handling 128 devices
exits, before and after this change:

before: 1.11s
after: 0.09s

Signed-off-by: Uday Shankar 
Reviewed-by: Ming Lei 
Link: https://lore.kernel.org/r/20250808-ublk_quiesce2-v1-1-f87ade33fa3d@purestorage.com
Signed-off-by: Jens Axboe

drbd: Remove the open-coded page pool

2025-08-11T13:54:27+00:00

If the network stack keeps a reference for too long, DRBD keeps
references on a higher number of pages as a consequence.

Fix all that by no longer relying on page reference counts dropping to
an expected value. Instead, DRBD gives up its reference and lets the
system handle everything else. While at it, remove the open-coded
custom page pool mechanism and use the page_pool included in the
kernel.

Signed-off-by: Philipp Reisner 
Signed-off-by: Christoph Böhmwalder 
Tested-by: Eric Hagberg 
Link: https://lore.kernel.org/r/20250605103852.23029-1-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe

Merge tag 'block-6.17-20250808' of git://git.kernel.dk/linux

2025-08-09T05:47:28+00:00

Pull more block updates from Jens Axboe:

 - MD pull request via Yu:
      - mddev null-ptr-dereference fix, by Erkun
      - md-cluster fail to remove the faulty disk regression fix, by
        Heming
      - minor cleanup, by Li Nan and Jinchao
      - mdadm lifetime regression fix reported by syzkaller, by Yu Kuai

 - MD pull request via Christoph
      - add support for getting the FDP featuee in fabrics passthru path
        (Nitesh Shetty)
      - add capability to connect to an administrative controller
        (Kamaljit Singh)
      - fix a leak on sgl setup error (Keith Busch)
      - initialize discovery subsys after debugfs is initialized
        (Mohamed Khalfella)
      - fix various comment typos (Bjorn Helgaas)
      - remove unneeded semicolons (Jiapeng Chong)

 - nvmet debugfs ordering issue fix

 - Fix UAF in the tag_set in zloop

 - Ensure sbitmap shallow depth covers entire set

 - Reduce lock roundtrips in io context lookup

 - Move scheduler tags alloc/free out of elevator and freeze lock, to
   fix some lockdep found issues

 - Improve robustness of queue limits checking

 - Fix a regression with IO priorities, if no io context exists

* tag 'block-6.17-20250808' of git://git.kernel.dk/linux: (26 commits)
  lib/sbitmap: make sbitmap_get_shallow() internal
  lib/sbitmap: convert shallow_depth from one word to the whole sbitmap
  nvmet: exit debugfs after discovery subsystem exits
  block, bfq: Reorder struct bfq_iocq_bfqq_data
  md: make rdev_addable usable for rcu mode
  md/raid1: remove struct pool_info and related code
  md/raid1: change r1conf->r1bio_pool to a pointer type
  block: ensure discard_granularity is zero when discard is not supported
  zloop: fix KASAN use-after-free of tag set
  block: Fix default IO priority if there is no IO context
  nvme: fix various comment typos
  nvme-auth: remove unneeded semicolon
  nvme-pci: fix leak on sgl setup error
  nvmet: initialize discovery subsys after debugfs is initialized
  nvme: add capability to connect to an administrative controller
  nvmet: add support for FDP in fabrics passthru path
  md: rename recovery_cp to resync_offset
  md/md-cluster: handle REMOVE message earlier
  md: fix create on open mddev lifetime regression
  block: fix potential deadlock while running nr_hw_queue update
  ...

Merge tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-07-31T21:57:54+00:00

Pull MM updates from Andrew Morton:
 "As usual, many cleanups. The below blurbiage describes 42 patchsets.
  21 of those are partially or fully cleanup work. "cleans up",
  "cleanup", "maintainability", "rationalizes", etc.

  I never knew the MM code was so dirty.

  "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes)
     addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly
     mapped VMAs were not eligible for merging with existing adjacent
     VMAs.

  "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park)
     adds a new kernel module which simplifies the setup and usage of
     DAMON in production environments.

  "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig)
     is a cleanup to the writeback code which removes a couple of
     pointers from struct writeback_control.

  "drivers/base/node.c: optimization and cleanups" (Donet Tom)
     contains largely uncorrelated cleanups to the NUMA node setup and
     management code.

  "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman)
     does some maintenance work on the userfaultfd code.

  "Readahead tweaks for larger folios" (Ryan Roberts)
     implements some tuneups for pagecache readahead when it is reading
     into order>0 folios.

  "selftests/mm: Tweaks to the cow test" (Mark Brown)
     provides some cleanups and consistency improvements to the
     selftests code.

  "Optimize mremap() for large folios" (Dev Jain)
     does that. A 37% reduction in execution time was measured in a
     memset+mremap+munmap microbenchmark.

  "Remove zero_user()" (Matthew Wilcox)
     expunges zero_user() in favor of the more modern memzero_page().

  "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand)
     addresses some warts which David noticed in the huge page code.
     These were not known to be causing any issues at this time.

  "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park)
     provides some cleanup and consolidation work in DAMON.

  "use vm_flags_t consistently" (Lorenzo Stoakes)
     uses vm_flags_t in places where we were inappropriately using other
     types.

  "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy)
     increases the reliability of large page allocation in the memfd
     code.

  "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple)
     removes several now-unneeded PFN_* flags.

  "mm/damon: decouple sysfs from core" (SeongJae Park)
     implememnts some cleanup and maintainability work in the DAMON
     sysfs layer.

  "madvise cleanup" (Lorenzo Stoakes)
     does quite a lot of cleanup/maintenance work in the madvise() code.

  "madvise anon_name cleanups" (Vlastimil Babka)
     provides additional cleanups on top or Lorenzo's effort.

  "Implement numa node notifier" (Oscar Salvador)
     creates a standalone notifier for NUMA node memory state changes.
     Previously these were lumped under the more general memory
     on/offline notifier.

  "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan)
     cleans up the pageblock isolation code and fixes a potential issue
     which doesn't seem to cause any problems in practice.

  "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park)
     adds additional drgn- and python-based DAMON selftests which are
     more comprehensive than the existing selftest suite.

  "Misc rework on hugetlb faulting path" (Oscar Salvador)
     fixes a rather obscure deadlock in the hugetlb fault code and
     follows that fix with a series of cleanups.

  "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport)
     rationalizes and cleans up the highmem-specific code in the CMA
     allocator.

  "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand)
     provides cleanups and future-preparedness to the migration code.

  "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park)
     adds some tracepoints to some DAMON auto-tuning code.

  "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park)
     does that.

  "mm/damon: misc cleanups" (SeongJae Park)
     also does what it claims.

  "mm: folio_pte_batch() improvements" (David Hildenbrand)
     cleans up the large folio PTE batching code.

  "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park)
     facilitates dynamic alteration of DAMON's inter-node allocation
     policy.

  "Remove unmap_and_put_page()" (Vishal Moola)
     provides a couple of page->folio conversions.

  "mm: per-node proactive reclaim" (Davidlohr Bueso)
     implements a per-node control of proactive reclaim - beyond the
     current memcg-based implementation.

  "mm/damon: remove damon_callback" (SeongJae Park)
     replaces the damon_callback interface with a more general and
     powerful damon_call()+damos_walk() interface.

  "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes)
     implements a number of mremap cleanups (of course) in preparation
     for adding new mremap() functionality: newly permit the remapping
     of multiple VMAs when the user is specifying MREMAP_FIXED. It still
     excludes some specialized situations where this cannot be performed
     reliably.

  "drop hugetlb_free_pgd_range()" (Anthony Yznaga)
     switches some sparc hugetlb code over to the generic version and
     removes the thus-unneeded hugetlb_free_pgd_range().

  "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park)
     augments the present userspace-requested update of DAMON sysfs
     monitoring files. Automatic update is now provided, along with a
     tunable to control the update interval.

  "Some randome fixes and cleanups to swapfile" (Kemeng Shi)
     does what is claims.

  "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand)
     provides (and uses) a means by which debug-style functions can grab
     a copy of a pageframe and inspect it locklessly without tripping
     over the races inherent in operating on the live pageframe
     directly.

  "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan)
     addresses the large contention issues which can be triggered by
     reads from that procfs file. Latencies are reduced by more than
     half in some situations. The series also introduces several new
     selftests for the /proc/pid/maps interface.

  "__folio_split() clean up" (Zi Yan)
     cleans up __folio_split()!

  "Optimize mprotect() for large folios" (Dev Jain)
     provides some quite large (>3x) speedups to mprotect() when dealing
     with large folios.

  "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian)
     does some cleanup work in the selftests code.

  "tools/testing: expand mremap testing" (Lorenzo Stoakes)
     extends the mremap() selftest in several ways, including adding
     more checking of Lorenzo's recently added "permit mremap() move of
     multiple VMAs" feature.

  "selftests/damon/sysfs.py: test all parameters" (SeongJae Park)
     extends the DAMON sysfs interface selftest so that it tests all
     possible user-requested parameters. Rather than the present minimal
     subset"

* tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits)
  MAINTAINERS: add missing headers to mempory policy & migration section
  MAINTAINERS: add missing file to cgroup section
  MAINTAINERS: add MM MISC section, add missing files to MISC and CORE
  MAINTAINERS: add missing zsmalloc file
  MAINTAINERS: add missing files to page alloc section
  MAINTAINERS: add missing shrinker files
  MAINTAINERS: move memremap.[ch] to hotplug section
  MAINTAINERS: add missing mm_slot.h file THP section
  MAINTAINERS: add missing interval_tree.c to memory mapping section
  MAINTAINERS: add missing percpu-internal.h file to per-cpu section
  mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info()
  selftests/damon: introduce _common.sh to host shared function
  selftests/damon/sysfs.py: test runtime reduction of DAMON parameters
  selftests/damon/sysfs.py: test non-default parameters runtime commit
  selftests/damon/sysfs.py: generalize DAMON context commit assertion
  selftests/damon/sysfs.py: generalize monitoring attributes commit assertion
  selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion
  selftests/damon/sysfs.py: test DAMOS filters commitment
  selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion
  selftests/damon/sysfs.py: test DAMOS destinations commitment
  ...

zloop: fix KASAN use-after-free of tag set

2025-07-31T21:01:07+00:00

When a zoned loop device, or zloop device, is removed, KASAN enabled
kernel reports "BUG KASAN use-after-free" in blk_mq_free_tag_set(). The
BUG happens because zloop_ctl_remove() calls put_disk(), which invokes
zloop_free_disk(). The zloop_free_disk() frees the memory allocated for
the zlo pointer. However, after the memory is freed, zloop_ctl_remove()
calls blk_mq_free_tag_set(&zlo->tag_set), which accesses the freed zlo.
Hence the KASAN use-after-free.

 zloop_ctl_remove()
  put_disk(zlo->disk)
   put_device()
    kobject_put()
     ...
      zloop_free_disk()
        kvfree(zlo)
  blk_mq_free_tag_set(&zlo->tag_set)

To avoid the BUG, move the call to blk_mq_free_tag_set(&zlo->tag_set)
from zloop_ctl_remove() into zloop_free_disk(). This ensures that
the tag_set is freed before the call to kvfree(zlo).

Fixes: eb0570c7df23 ("block: new zoned loop block device driver")
CC: stable@vger.kernel.org
Signed-off-by: Shin'ichiro Kawasaki 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20250731110745.165751-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe