lwn.git/drivers/md, branch v6.8-rc5

dm-crypt, dm-verity: disable tasklets

2024-02-02T17:33:50+00:00

Tasklets have an inherent problem with memory corruption. The function tasklet_action_common calls tasklet_trylock, then it calls the tasklet callback and then it calls tasklet_unlock. If the tasklet callback frees the structure that contains the tasklet or if it calls some code that may free it, tasklet_unlock will write into free memory. The commits 8e14f610159d and d9a02e016aaf try to fix it for dm-crypt, but it is not a sufficient fix and the data corruption can still happen [1]. There is no fix for dm-verity and dm-verity will write into free memory with every tasklet-processed bio. There will be atomic workqueues implemented in the kernel 6.9 [2]. They will have better interface and they will not suffer from the memory corruption problem. But we need something that stops the memory corruption now and that can be backported to the stable kernels. So, I'm proposing this commit that disables tasklets in both dm-crypt and dm-verity. This commit doesn't remove the tasklet support, because the tasklet code will be reused when atomic workqueues will be implemented. [1] https://lore.kernel.org/all/d390d7ee-f142-44d3-822a-87949e14608b@suse.de/T/ [2] https://lore.kernel.org/lkml/20240130091300.2968534-1-tj@kernel.org/ Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Fixes: 39d42fa96ba1b ("dm crypt: add flags to optionally bypass kcryptd workqueues") Fixes: 5721d4e5a9cdb ("dm verity: Add optional "try_verify_in_tasklet" feature") Signed-off-by: Mike Snitzer

dm writecache: allow allocations larger than 2GiB

2024-01-30T19:07:30+00:00

The function kvmalloc_node limits the allocation size to INT_MAX. This limit will be overflowed if dm-writecache attempts to map a device with 1TiB or larger length. This commit changes kvmalloc_array to vmalloc_array to avoid the limit. The commit also changes vmalloc(array_size()) to vmalloc_array(). Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

dm stats: limit the number of entries

2024-01-30T19:06:44+00:00

The kvmalloc function fails with a warning if the size is larger than INT_MAX. Linus said that there should be limits that prevent this warning from being hit. This commit adds the limits to the dm-stats subsystem in DM core. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

dm: limit the number of targets and parameter size area

2024-01-30T19:05:02+00:00

The kvmalloc function fails with a warning if the size is larger than INT_MAX. The warning was triggered by a syscall testing robot. In order to avoid the warning, this commit limits the number of targets to 1048576 and the size of the parameter area to 1073741824. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

md: fix a suspicious RCU usage warning

2024-01-25T06:58:00+00:00

RCU protection was removed in the commit 2d32777d60de ("raid1: remove rcu protection to access rdev from conf"). However, the code in fix_read_error does rcu_dereference outside rcu_read_lock - this triggers the following warning. The warning is triggered by a LVM2 test shell/integrity-caching.sh. This commit removes rcu_dereference. ============================= WARNING: suspicious RCU usage 6.7.0 #2 Not tainted ----------------------------- drivers/md/raid1.c:2265 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 no locks held by mdX_raid1/1859. stack backtrace: CPU: 2 PID: 1859 Comm: mdX_raid1 Not tainted 6.7.0 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x60/0x70 lockdep_rcu_suspicious+0x153/0x1b0 raid1d+0x1732/0x1750 [raid1] ? lock_acquire+0x9f/0x270 ? finish_wait+0x3d/0x80 ? md_thread+0xf7/0x130 [md_mod] ? lock_release+0xaa/0x230 ? md_register_thread+0xd0/0xd0 [md_mod] md_thread+0xa0/0x130 [md_mod] ? housekeeping_test_cpu+0x30/0x30 kthread+0xdc/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x28/0x40 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork_asm+0x11/0x20 Signed-off-by: Mikulas Patocka Fixes: ca294b34aaf3 ("md/raid1: support read error check") Reviewed-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/51539879-e1ca-fde3-b8b4-8934ddedcbc@redhat.com

Merge tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linux

2024-01-19T02:22:40+00:00

Pull block fixes from Jens Axboe: - NVMe pull request via Keith: - tcp, fc, and rdma target fixes (Maurizio, Daniel, Hannes, Christoph) - discard fixes and improvements (Christoph) - timeout debug improvements (Keith, Max) - various cleanups (Daniel, Max, Giuxen) - trace event string fixes (Arnd) - shadow doorbell setup on reset fix (William) - a write zeroes quirk for SK Hynix (Jim) - MD pull request via Song: - Sparse warning since v6.0 (Bart) - /proc/mdstat regression since v6.7 (Yu Kuai) - Use symbolic error value (Christian) - IO Priority documentation update (Christian) - Fix for accessing queue limits without having entered the queue (Christoph, me) - Fix for loop dio support (Christoph) - Move null_blk off deprecated ida interface (Christophe) - Ensure nbd initializes full msghdr (Eric) - Fix for a regression with the folio conversion, which is now easier to hit because of an unrelated change (Matthew) - Remove redundant check in virtio-blk (Li) - Fix for a potential hang in sbitmap (Ming) - Fix for partial zone appending (Damien) - Misc changes and fixes (Bart, me, Kemeng, Dmitry) * tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linux: (45 commits) Documentation: block: ioprio: Update schedulers loop: fix the the direct I/O support check when used on top of block devices blk-mq: Remove the hctx 'run' debugfs attribute nbd: always initialize struct msghdr completely block: Fix iterating over an empty bio with bio_for_each_folio_all block: bio-integrity: fix kcalloc() arguments order virtio_blk: remove duplicate check if queue is broken in virtblk_done sbitmap: remove stale comment in sbq_calc_wake_batch block: Correct a documentation comment in blk-cgroup.c null_blk: Remove usage of the deprecated ida_simple_xx() API block: ensure we hold a queue reference when using queue limits blk-mq: rename blk_mq_can_use_cached_rq block: print symbolic error name instead of error code blk-mq: fix IO hang from sbitmap wakeup race nvmet-rdma: avoid circular locking dependency on install_queue() nvmet-tcp: avoid circular locking dependency on install_queue() nvme-pci: set doorbell config before unquiescing block: fix partial zone append completion handling in req_bio_endio() block/iocost: silence warning on 'last_period' potentially being unused md/raid1: Use blk_opf_t for read and write operations ...

Merge tag 'for-6.8/block-2024-01-08' of git://git.kernel.dk/linux

2024-01-11T21:58:04+00:00

Pull block updates from Jens Axboe: "Pretty quiet round this time around. This contains: - NVMe updates via Keith: - nvme fabrics spec updates (Guixin, Max) - nvme target udpates (Guixin, Evan) - nvme attribute refactoring (Daniel) - nvme-fc numa fix (Keith) - MD updates via Song: - Fix/Cleanup RCU usage from conf->disks[i].rdev (Yu Kuai) - Fix raid5 hang issue (Junxiao Bi) - Add Yu Kuai as Reviewer of the md subsystem - Remove deprecated flavors (Song Liu) - raid1 read error check support (Li Nan) - Better handle events off-by-1 case (Alex Lyakas) - Efficiency improvements for passthrough (Kundan) - Support for mapping integrity data directly (Keith) - Zoned write fix (Damien) - rnbd fixes (Kees, Santosh, Supriti) - Default to a sane discard size granularity (Christoph) - Make the default max transfer size naming less confusing (Christoph) - Remove support for deprecated host aware zoned model (Christoph) - Misc fixes (me, Li, Matthew, Min, Ming, Randy, liyouhong, Daniel, Bart, Christoph)" * tag 'for-6.8/block-2024-01-08' of git://git.kernel.dk/linux: (78 commits) block: Treat sequential write preferred zone type as invalid block: remove disk_clear_zoned sd: remove the !ZBC && blk_queue_is_zoned case in sd_read_block_characteristics drivers/block/xen-blkback/common.h: Fix spelling typo in comment blk-cgroup: fix rcu lockdep warning in blkg_lookup() blk-cgroup: don't use removal safe list iterators block: floor the discard granularity to the physical block size mtd_blkdevs: use the default discard granularity bcache: use the default discard granularity zram: use the default discard granularity null_blk: use the default discard granularity nbd: use the default discard granularity ubd: use the default discard granularity block: default the discard granularity to sector size bcache: discard_granularity should not be smaller than a sector block: remove two comments in bio_split_discard block: rename and document BLK_DEF_MAX_SECTORS loop: don't abuse BLK_DEF_MAX_SECTORS aoe: don't abuse BLK_DEF_MAX_SECTORS null_blk: don't cap max_hw_sectors to BLK_DEF_MAX_SECTORS ...

md/raid1: Use blk_opf_t for read and write operations

2024-01-09T23:14:01+00:00

Use the type blk_opf_t for read and write operations instead of int. This patch does not affect the generated code but fixes the following sparse warning: drivers/md/raid1.c:1993:60: sparse: sparse: incorrect type in argument 5 (different base types) expected restricted blk_opf_t [usertype] opf got int rw Cc: Song Liu Cc: Jens Axboe Fixes: 3c5e514db58f ("md/raid1: Use the new blk_opf_t type") Cc: stable@vger.kernel.org # v6.0+ Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202401080657.UjFnvQgX-lkp@intel.com/ Signed-off-by: Bart Van Assche Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20240108001223.23835-1-bvanassche@acm.org

Merge tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-01-09T19:18:47+00:00

Pull MM updates from Andrew Morton: "Many singleton patches against the MM code. The patch series which are included in this merge do the following: - Peng Zhang has done some mapletree maintainance work in the series 'maple_tree: add mt_free_one() and mt_attr() helpers' 'Some cleanups of maple tree' - In the series 'mm: use memmap_on_memory semantics for dax/kmem' Vishal Verma has altered the interworking between memory-hotplug and dax/kmem so that newly added 'device memory' can more easily have its memmap placed within that newly added memory. - Matthew Wilcox continues folio-related work (including a few fixes) in the patch series 'Add folio_zero_tail() and folio_fill_tail()' 'Make folio_start_writeback return void' 'Fix fault handler's handling of poisoned tail pages' 'Convert aops->error_remove_page to ->error_remove_folio' 'Finish two folio conversions' 'More swap folio conversions' - Kefeng Wang has also contributed folio-related work in the series 'mm: cleanup and use more folio in page fault' - Jim Cromie has improved the kmemleak reporting output in the series 'tweak kmemleak report format'. - In the series 'stackdepot: allow evicting stack traces' Andrey Konovalov to permits clients (in this case KASAN) to cause eviction of no longer needed stack traces. - Charan Teja Kalla has fixed some accounting issues in the page allocator's atomic reserve calculations in the series 'mm: page_alloc: fixes for high atomic reserve caluculations'. - Dmitry Rokosov has added to the samples/ dorectory some sample code for a userspace memcg event listener application. See the series 'samples: introduce cgroup events listeners'. - Some mapletree maintanance work from Liam Howlett in the series 'maple_tree: iterator state changes'. - Nhat Pham has improved zswap's approach to writeback in the series 'workload-specific and memory pressure-driven zswap writeback'. - DAMON/DAMOS feature and maintenance work from SeongJae Park in the series 'mm/damon: let users feed and tame/auto-tune DAMOS' 'selftests/damon: add Python-written DAMON functionality tests' 'mm/damon: misc updates for 6.8' - Yosry Ahmed has improved memcg's stats flushing in the series 'mm: memcg: subtree stats flushing and thresholds'. - In the series 'Multi-size THP for anonymous memory' Ryan Roberts has added a runtime opt-in feature to transparent hugepages which improves performance by allocating larger chunks of memory during anonymous page faults. - Matthew Wilcox has also contributed some cleanup and maintenance work against eh buffer_head code int he series 'More buffer_head cleanups'. - Suren Baghdasaryan has done work on Andrea Arcangeli's series 'userfaultfd move option'. UFFDIO_MOVE permits userspace heap compaction algorithms to move userspace's pages around rather than UFFDIO_COPY'a alloc/copy/free. - Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm: Add ksm advisor'. This is a governor which tunes KSM's scanning aggressiveness in response to userspace's current needs. - Chengming Zhou has optimized zswap's temporary working memory use in the series 'mm/zswap: dstmem reuse optimizations and cleanups'. - Matthew Wilcox has performed some maintenance work on the writeback code, both code and within filesystems. The series is 'Clean up the writeback paths'. - Andrey Konovalov has optimized KASAN's handling of alloc and free stack traces for secondary-level allocators, in the series 'kasan: save mempool stack traces'. - Andrey also performed some KASAN maintenance work in the series 'kasan: assorted clean-ups'. - David Hildenbrand has gone to town on the rmap code. Cleanups, more pte batching, folio conversions and more. See the series 'mm/rmap: interface overhaul'. - Kinsey Ho has contributed some maintenance work on the MGLRU code in the series 'mm/mglru: Kconfig cleanup'. - Matthew Wilcox has contributed lruvec page accounting code cleanups in the series 'Remove some lruvec page accounting functions'" * tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits) mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER mm, treewide: introduce NR_PAGE_ORDERS selftests/mm: add separate UFFDIO_MOVE test for PMD splitting selftests/mm: skip test if application doesn't has root privileges selftests/mm: conform test to TAP format output selftests: mm: hugepage-mmap: conform to TAP format output selftests/mm: gup_test: conform test to TAP format output mm/selftests: hugepage-mremap: conform test to TAP format output mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large mm/memcontrol: remove __mod_lruvec_page_state() mm/khugepaged: use a folio more in collapse_file() slub: use a folio in __kmalloc_large_node slub: use folio APIs in free_large_kmalloc() slub: use alloc_pages_node() in alloc_slab_page() mm: remove inc/dec lruvec page state functions mm: ratelimit stat flush from workingset shrinker kasan: stop leaking stack trace handles mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE mm/mglru: add dummy pmd_dirty() ...

md: Fix md_seq_ops() regressions

2024-01-09T18:08:18+00:00

Commit cf1b6d4441ff ("md: simplify md_seq_ops") introduce following regressions: 1) If list all_mddevs is emptly, personalities and unused devices won't be showed to user anymore. 2) If seq_file buffer overflowed from md_seq_show(), then md_seq_start() will be called again, hence personalities will be showed to user again. 3) If seq_file buffer overflowed from md_seq_stop(), seq_read_iter() doesn't handle this, hence unused devices won't be showed to user. Fix above problems by printing personalities and unused devices in md_seq_show(). Fixes: cf1b6d4441ff ("md: simplify md_seq_ops") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20240109133957.2975272-1-yukuai1@huaweicloud.com