kernel/linux.git/drivers/md/raid5.c, branch v5.9.12

md/raid5: fix oops during stripe resizing

2020-11-05T10:51:31+00:00

commit b44c018cdf748b96b676ba09fdbc5b34fc443ada upstream. KoWei reported crash during raid5 reshape: [ 1032.252932] Oops: 0002 [#1] SMP PTI [...] [ 1032.252943] RIP: 0010:memcpy_erms+0x6/0x10 [...] [ 1032.252947] RSP: 0018:ffffba1ac0c03b78 EFLAGS: 00010286 [ 1032.252949] RAX: 0000784ac0000000 RBX: ffff91bec3d09740 RCX: 0000000000001000 [ 1032.252951] RDX: 0000000000001000 RSI: ffff91be6781c000 RDI: 0000784ac0000000 [ 1032.252953] RBP: ffffba1ac0c03bd8 R08: 0000000000001000 R09: ffffba1ac0c03bf8 [ 1032.252954] R10: 0000000000000000 R11: 0000000000000000 R12: ffffba1ac0c03bf8 [ 1032.252955] R13: 0000000000001000 R14: 0000000000000000 R15: 0000000000000000 [ 1032.252958] FS: 0000000000000000(0000) GS:ffff91becf500000(0000) knlGS:0000000000000000 [ 1032.252959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1032.252961] CR2: 0000784ac0000000 CR3: 000000031780a002 CR4: 00000000001606e0 [ 1032.252962] Call Trace: [ 1032.252969] ? async_memcpy+0x179/0x1000 [async_memcpy] [ 1032.252977] ? raid5_release_stripe+0x8e/0x110 [raid456] [ 1032.252982] handle_stripe_expansion+0x15a/0x1f0 [raid456] [ 1032.252988] handle_stripe+0x592/0x1270 [raid456] [ 1032.252993] handle_active_stripes.isra.0+0x3cb/0x5a0 [raid456] [ 1032.252999] raid5d+0x35c/0x550 [raid456] [ 1032.253002] ? schedule+0x42/0xb0 [ 1032.253006] ? schedule_timeout+0x10e/0x160 [ 1032.253011] md_thread+0x97/0x160 [ 1032.253015] ? wait_woken+0x80/0x80 [ 1032.253019] kthread+0x104/0x140 [ 1032.253022] ? md_start_sync+0x60/0x60 [ 1032.253024] ? kthread_park+0x90/0x90 [ 1032.253027] ret_from_fork+0x35/0x40 This is because cache_size_mutex was unlocked too early in resize_stripes, which races with grow_one_stripe() that grow_one_stripe() allocates a stripe with wrong pool_size. Fix this issue by unlocking cache_size_mutex after updating pool_size. Cc: # v4.4+ Reported-by: KoWei Sung Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman

Merge tag 'block-5.9-2020-08-28' of git://git.kernel.dk/linux-block

2020-08-28T23:38:29+00:00

Pull block fixes from Jens Axboe: - nbd timeout fix (Hou) - device size fix for loop LOOP_CONFIGURE (Martijn) - MD pull from Song with raid5 stripe size fix (Yufen) * tag 'block-5.9-2020-08-28' of git://git.kernel.dk/linux-block: md/raid5: make sure stripe_size as power of two loop: Set correct device size when using LOOP_CONFIGURE nbd: restore default timeout when setting it to zero

md/raid5: make sure stripe_size as power of two

2020-08-28T05:41:03+00:00

Commit 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs entry") make stripe_size as a configurable value. It just requires stripe_size as multiple of 4KB. In fact, we should make sure stripe_size as power of two. Otherwise, stripe_shift which is the result of ilog2 can not represent the real stripe_size. Then, stripe_hash() and stripe_hash_locks_hash() may get unexpected value. Fixes: 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs entry") Signed-off-by: Yufen Yu Signed-off-by: Song Liu

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

Merge tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-08-11T02:07:44+00:00

Pull locking updates from Thomas Gleixner: "A set of locking fixes and updates: - Untangle the header spaghetti which causes build failures in various situations caused by the lockdep additions to seqcount to validate that the write side critical sections are non-preemptible. - The seqcount associated lock debug addons which were blocked by the above fallout. seqcount writers contrary to seqlock writers must be externally serialized, which usually happens via locking - except for strict per CPU seqcounts. As the lock is not part of the seqcount, lockdep cannot validate that the lock is held. This new debug mechanism adds the concept of associated locks. sequence count has now lock type variants and corresponding initializers which take a pointer to the associated lock used for writer serialization. If lockdep is enabled the pointer is stored and write_seqcount_begin() has a lockdep assertion to validate that the lock is held. Aside of the type and the initializer no other code changes are required at the seqcount usage sites. The rest of the seqcount API is unchanged and determines the type at compile time with the help of _Generic which is possible now that the minimal GCC version has been moved up. Adding this lockdep coverage unearthed a handful of seqcount bugs which have been addressed already independent of this. While generally useful this comes with a Trojan Horse twist: On RT kernels the write side critical section can become preemtible if the writers are serialized by an associated lock, which leads to the well known reader preempts writer livelock. RT prevents this by storing the associated lock pointer independent of lockdep in the seqcount and changing the reader side to block on the lock when a reader detects that a writer is in the write side critical section. - Conversion of seqcount usage sites to associated types and initializers" * tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits) locking/seqlock, headers: Untangle the spaghetti monster locking, arch/ia64: Reduce header dependencies by moving XTP bits into the new header x86/headers: Remove APIC headers from seqcount: More consistent seqprop names seqcount: Compress SEQCNT_LOCKNAME_ZERO() seqlock: Fold seqcount_LOCKNAME_init() definition seqlock: Fold seqcount_LOCKNAME_t definition seqlock: s/__SEQ_LOCKDEP/__SEQ_LOCK/g hrtimer: Use sequence counter with associated raw spinlock kvm/eventfd: Use sequence counter with associated spinlock userfaultfd: Use sequence counter with associated spinlock NFSv4: Use sequence counter with associated spinlock iocost: Use sequence counter with associated spinlock raid5: Use sequence counter with associated spinlock vfs: Use sequence counter with associated spinlock timekeeping: Use sequence counter with associated raw spinlock xfrm: policy: Use sequence counters with associated lock netfilter: nft_set_rbtree: Use sequence counter with associated rwlock netfilter: conntrack: Use sequence counter with associated spinlock sched: tasks: Use sequence counter with associated spinlock ...

Merge tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block

2020-08-05T17:51:40+00:00

Pull block driver updates from Jens Axboe: - NVMe: - ZNS support (Aravind, Keith, Matias, Niklas) - Misc cleanups, optimizations, fixes (Baolin, Chaitanya, David, Dongli, Max, Sagi) - null_blk zone capacity support (Aravind) - MD: - raid5/6 fixes (ChangSyun) - Warning fixes (Damien) - raid5 stripe fixes (Guoqing, Song, Yufen) - sysfs deadlock fix (Junxiao) - raid10 deadlock fix (Vitaly) - struct_size conversions (Gustavo) - Set of bcache updates/fixes (Coly) * tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block: (117 commits) md/raid5: Allow degraded raid6 to do rmw md/raid5: Fix Force reconstruct-write io stuck in degraded raid5 raid5: don't duplicate code for different paths in handle_stripe raid5-cache: hold spinlock instead of mutex in r5c_journal_mode_show md: print errno in super_written md/raid5: remove the redundant setting of STRIPE_HANDLE md: register new md sysfs file 'uuid' read-only md: fix max sectors calculation for super 1.0 nvme-loop: remove extra variable in create ctrl nvme-loop: set ctrl state connecting after init nvme-multipath: do not fall back to __nvme_find_path() for non-optimized paths nvme-multipath: fix logic for non-optimized paths nvme-rdma: fix controller reset hang during traffic nvme-tcp: fix controller reset hang during traffic nvmet: introduce the passthru Kconfig option nvmet: introduce the passthru configfs interface nvmet: Add passthru enable/disable helpers nvmet: add passthru code to process commands nvme: export nvme_find_get_ns() and nvme_put_ns() nvme: introduce nvme_ctrl_get_by_path() ...

Merge tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2020-08-04T20:49:43+00:00

Pull uninitialized_var() macro removal from Kees Cook: "This is long overdue, and has hidden too many bugs over the years. The series has several "by hand" fixes, and then a trivial treewide replacement. - Clean up non-trivial uses of uninitialized_var() - Update documentation and checkpatch for uninitialized_var() removal - Treewide removal of uninitialized_var()" * tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: compiler: Remove uninitialized_var() macro treewide: Remove uninitialized_var() usage checkpatch: Remove awareness of uninitialized_var() macro mm/debug_vm_pgtable: Remove uninitialized_var() usage f2fs: Eliminate usage of uninitialized_var() macro media: sur40: Remove uninitialized_var() usage KVM: PPC: Book3S PR: Remove uninitialized_var() usage clk: spear: Remove uninitialized_var() usage clk: st: Remove uninitialized_var() usage spi: davinci: Remove uninitialized_var() usage ide: Remove uninitialized_var() usage rtlwifi: rtl8192cu: Remove uninitialized_var() usage b43: Remove uninitialized_var() usage drbd: Remove uninitialized_var() usage x86/mm/numa: Remove uninitialized_var() usage docs: deprecated.rst: Add uninitialized_var()

md/raid5: Allow degraded raid6 to do rmw

2020-08-03T06:54:31+00:00

Degraded raid6 always do reconstruct-write now. With raid6 xor supported, we can do rmw in degraded raid6. This patch can reduce many read IOs to improve performance. If the failed disk is P, Q or the disk we want to write to, we may need to do reconstruct-write in max degraded raid6. In this situation we can not read enough data from handle_stripe_dirtying() so we have to set force_rcw in handle_stripe_fill() to read all data. Reviewed-by: Alex Wu Reviewed-by: BingJing Chang Reviewed-by: Danny Shih Signed-off-by: ChangSyun Peng Signed-off-by: Song Liu

md/raid5: Fix Force reconstruct-write io stuck in degraded raid5

2020-08-03T06:54:25+00:00

In degraded raid5, we need to read parity to do reconstruct-write when data disks fail. However, we can not read parity from handle_stripe_dirtying() in force reconstruct-write mode. Reproducible Steps: 1. Create degraded raid5 mdadm -C /dev/md2 --assume-clean -l5 -n3 /dev/sda2 /dev/sdb2 missing 2. Set rmw_level to 0 echo 0 > /sys/block/md2/md/rmw_level 3. IO to raid5 Now some io may be stuck in raid5. We can use handle_stripe_fill() to read the parity in this situation. Cc: # v4.4+ Reviewed-by: Alex Wu Reviewed-by: BingJing Chang Reviewed-by: Danny Shih Signed-off-by: ChangSyun Peng Signed-off-by: Song Liu

raid5: don't duplicate code for different paths in handle_stripe

2020-08-03T06:03:52+00:00

As we can see, R5_LOCKED is set and s.locked is increased whether R5_ReWrite is set or not, so move it to common path. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu