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2020-05-10Merge tag 'block-5.7-2020-05-09' of git://git.kernel.dk/linux-blockLinus Torvalds2-2/+2
Pull block fixes from Jens Axboe: - a small series fixing a use-after-free of bdi name (Christoph,Yufen) - NVMe fix for a regression with the smaller CQ update (Alexey) - NVMe fix for a hang at namespace scanning error recovery (Sagi) - fix race with blk-iocost iocg->abs_vdebt updates (Tejun) * tag 'block-5.7-2020-05-09' of git://git.kernel.dk/linux-block: nvme: fix possible hang when ns scanning fails during error recovery nvme-pci: fix "slimmer CQ head update" bdi: add a ->dev_name field to struct backing_dev_info bdi: use bdi_dev_name() to get device name bdi: move bdi_dev_name out of line vboxsf: don't use the source name in the bdi name iocost: protect iocg->abs_vdebt with iocg->waitq.lock
2020-05-10bdi: use bdi_dev_name() to get device nameYufen Yu1-1/+1
Use the common interface bdi_dev_name() to get device name. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Add missing <linux/backing-dev.h> include BFQ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-09Merge tag 'io_uring-5.7-2020-05-08' of git://git.kernel.dk/linux-blockLinus Torvalds2-70/+40
Pull io_uring fixes from Jens Axboe: - Fix finish_wait() balancing in file cancelation (Xiaoguang) - Ensure early cleanup of resources in ring map failure (Xiaoguang) - Ensure IORING_OP_SLICE does the right file mode checks (Pavel) - Remove file opening from openat/openat2/statx, it's not needed and messes with O_PATH * tag 'io_uring-5.7-2020-05-08' of git://git.kernel.dk/linux-block: io_uring: don't use 'fd' for openat/openat2/statx splice: move f_mode checks to do_{splice,tee}() io_uring: handle -EFAULT properly in io_uring_setup() io_uring: fix mismatched finish_wait() calls in io_uring_cancel_files()
2020-05-08Merge tag 'ceph-for-5.7-rc5' of git://github.com/ceph/ceph-clientLinus Torvalds3-8/+7
Pull ceph fixes from Ilya Dryomov: "Fixes for an endianness handling bug that prevented mounts on big-endian arches, a spammy log message and a couple error paths. Also included a MAINTAINERS update" * tag 'ceph-for-5.7-rc5' of git://github.com/ceph/ceph-client: ceph: demote quotarealm lookup warning to a debug message MAINTAINERS: remove myself as ceph co-maintainer ceph: fix double unlock in handle_cap_export() ceph: fix special error code in ceph_try_get_caps() ceph: fix endianness bug when handling MDS session feature bits
2020-05-08ceph: demote quotarealm lookup warning to a debug messageLuis Henriques1-2/+2
A misconfigured cephx can easily result in having the kernel client flooding the logs with: ceph: Can't lookup inode 1 (err: -13) Change this message to debug level. Cc: stable@vger.kernel.org URL: https://tracker.ceph.com/issues/44546 Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-05-08Merge tag 'driver-core-5.7-rc5' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core fixes from Greg KH: "Here are a number of small driver core fixes for 5.7-rc5 to resolve a bunch of reported issues with the current tree. Biggest here are the reverts and patches from John Stultz to resolve a bunch of deferred probe regressions we have been seeing in 5.7-rc right now. Along with those are some other smaller fixes: - coredump crash fix - devlink fix for when permissive mode was enabled - amba and platform device dma_parms fixes - component error silenced for when deferred probe happens All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: regulator: Revert "Use driver_deferred_probe_timeout for regulator_init_complete_work" driver core: Ensure wait_for_device_probe() waits until the deferred_probe_timeout fires driver core: Use dev_warn() instead of dev_WARN() for deferred_probe_timeout warnings driver core: Revert default driver_deferred_probe_timeout value to 0 component: Silence bind error on -EPROBE_DEFER driver core: Fix handling of fw_devlink=permissive coredump: fix crash when umh is disabled amba: Initialize dma_parms for amba devices driver core: platform: Initialize dma_parms for platform devices
2020-05-08Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-28/+33
Merge misc fixes from Andrew Morton: "14 fixes and one selftest to verify the ipc fixes herein" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm: limit boost_watermark on small zones ubsan: disable UBSAN_ALIGNMENT under COMPILE_TEST mm/vmscan: remove unnecessary argument description of isolate_lru_pages() epoll: atomically remove wait entry on wake up kselftests: introduce new epoll60 testcase for catching lost wakeups percpu: make pcpu_alloc() aware of current gfp context mm/slub: fix incorrect interpretation of s->offset scripts/gdb: repair rb_first() and rb_last() eventpoll: fix missing wakeup for ovflist in ep_poll_callback arch/x86/kvm/svm/sev.c: change flag passed to GUP fast in sev_pin_memory() scripts/decodecode: fix trapping instruction formatting kernel/kcov.c: fix typos in kcov_remote_start documentation mm/page_alloc: fix watchdog soft lockups during set_zone_contiguous() mm, memcg: fix error return value of mem_cgroup_css_alloc() ipc/mqueue.c: change __do_notify() to bypass check_kill_permission()
2020-05-08epoll: atomically remove wait entry on wake upRoman Penyaev1-19/+24
This patch does two things: - fixes a lost wakeup introduced by commit 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") - improves performance for events delivery. The description of the problem is the following: if N (>1) threads are waiting on ep->wq for new events and M (>1) events come, it is quite likely that >1 wakeups hit the same wait queue entry, because there is quite a big window between __add_wait_queue_exclusive() and the following __remove_wait_queue() calls in ep_poll() function. This can lead to lost wakeups, because thread, which was woken up, can handle not all the events in ->rdllist. (in better words the problem is described here: https://lkml.org/lkml/2019/10/7/905) The idea of the current patch is to use init_wait() instead of init_waitqueue_entry(). Internally init_wait() sets autoremove_wake_function as a callback, which removes the wait entry atomically (under the wq locks) from the list, thus the next coming wakeup hits the next wait entry in the wait queue, thus preventing lost wakeups. Problem is very well reproduced by the epoll60 test case [1]. Wait entry removal on wakeup has also performance benefits, because there is no need to take a ep->lock and remove wait entry from the queue after the successful wakeup. Here is the timing output of the epoll60 test case: With explicit wakeup from ep_scan_ready_list() (the state of the code prior 339ddb53d373): real 0m6.970s user 0m49.786s sys 0m0.113s After this patch: real 0m5.220s user 0m36.879s sys 0m0.019s The other testcase is the stress-epoll [2], where one thread consumes all the events and other threads produce many events: With explicit wakeup from ep_scan_ready_list() (the state of the code prior 339ddb53d373): threads events/ms run-time ms 8 5427 1474 16 6163 2596 32 6824 4689 64 7060 9064 128 6991 18309 After this patch: threads events/ms run-time ms 8 5598 1429 16 7073 2262 32 7502 4265 64 7640 8376 128 7634 16767 (number of "events/ms" represents event bandwidth, thus higher is better; number of "run-time ms" represents overall time spent doing the benchmark, thus lower is better) [1] tools/testing/selftests/filesystems/epoll/epoll_wakeup_test.c [2] https://github.com/rouming/test-tools/blob/master/stress-epoll.c Signed-off-by: Roman Penyaev <rpenyaev@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jason Baron <jbaron@akamai.com> Cc: Khazhismel Kumykov <khazhy@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Heiher <r@hev.cc> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200430130326.1368509-2-rpenyaev@suse.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-08eventpoll: fix missing wakeup for ovflist in ep_poll_callbackKhazhismel Kumykov1-9/+9
In the event that we add to ovflist, before commit 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") we would be woken up by ep_scan_ready_list, and did no wakeup in ep_poll_callback. With that wakeup removed, if we add to ovflist here, we may never wake up. Rather than adding back the ep_scan_ready_list wakeup - which was resulting in unnecessary wakeups, trigger a wake-up in ep_poll_callback. We noticed that one of our workloads was missing wakeups starting with 339ddb53d373 and upon manual inspection, this wakeup seemed missing to me. With this patch added, we no longer see missing wakeups. I haven't yet tried to make a small reproducer, but the existing kselftests in filesystem/epoll passed for me with this patch. [khazhy@google.com: use if/elif instead of goto + cleanup suggested by Roman] Link: http://lkml.kernel.org/r/20200424190039.192373-1-khazhy@google.com Fixes: 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") Signed-off-by: Khazhismel Kumykov <khazhy@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Roman Penyaev <rpenyaev@suse.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Roman Penyaev <rpenyaev@suse.de> Cc: Heiher <r@hev.cc> Cc: Jason Baron <jbaron@akamai.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200424025057.118641-1-khazhy@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07io_uring: don't use 'fd' for openat/openat2/statxJens Axboe1-25/+7
We currently make some guesses as when to open this fd, but in reality we have no business (or need) to do so at all. In fact, it makes certain things fail, like O_PATH. Remove the fd lookup from these opcodes, we're just passing the 'fd' to generic helpers anyway. With that, we can also remove the special casing of fd values in io_req_needs_file(), and the 'fd_non_neg' check that we have. And we can ensure that we only read sqe->fd once. This fixes O_PATH usage with openat/openat2, and ditto statx path side oddities. Cc: stable@vger.kernel.org: # v5.6 Reported-by: Max Kellermann <mk@cm4all.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-07Merge tag 'configfs-for-5.7' of git://git.infradead.org/users/hch/configfsLinus Torvalds1-0/+1
Pull configfs fix from Christoph Hellwig: "Fix a refcount leak in configfs_rmdir (Xiyu Yang)" * tag 'configfs-for-5.7' of git://git.infradead.org/users/hch/configfs: configfs: fix config_item refcnt leak in configfs_rmdir()
2020-05-07splice: move f_mode checks to do_{splice,tee}()Pavel Begunkov1-27/+18
do_splice() is used by io_uring, as will be do_tee(). Move f_mode checks from sys_{splice,tee}() to do_{splice,tee}(), so they're enforced for io_uring as well. Fixes: 7d67af2c0134 ("io_uring: add splice(2) support") Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-07vboxsf: don't use the source name in the bdi nameChristoph Hellwig1-1/+1
Simplify the bdi name to mirror what we are doing elsewhere, and drop them name in favor of just using a number. This avoids a potentially very long bdi name. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-05io_uring: handle -EFAULT properly in io_uring_setup()Xiaoguang Wang1-13/+11
If copy_to_user() in io_uring_setup() failed, we'll leak many kernel resources, which will be recycled until process terminates. This bug can be reproduced by using mprotect to set params to PROT_READ. To fix this issue, refactor io_uring_create() a bit to add a new 'struct io_uring_params __user *params' parameter and move the copy_to_user() in io_uring_setup() to io_uring_setup(), if copy_to_user() failed, we can free kernel resource properly. Suggested-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-04ceph: fix double unlock in handle_cap_export()Wu Bo1-0/+1
If the ceph_mdsc_open_export_target_session() return fails, it will do a "goto retry", but the session mutex has already been unlocked. Re-lock the mutex in that case to ensure that we don't unlock it twice. Signed-off-by: Wu Bo <wubo40@huawei.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-05-04ceph: fix special error code in ceph_try_get_caps()Wu Bo1-1/+1
There are 3 speical error codes: -EAGAIN/-EFBIG/-ESTALE. After calling try_get_cap_refs, ceph_try_get_caps test for the -EAGAIN twice. Ensure that it tests for -ESTALE instead. Signed-off-by: Wu Bo <wubo40@huawei.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-05-04ceph: fix endianness bug when handling MDS session feature bitsJeff Layton1-5/+3
Eduard reported a problem mounting cephfs on s390 arch. The feature mask sent by the MDS is little-endian, so we need to convert it before storing and testing against it. Cc: stable@vger.kernel.org Reported-and-Tested-by: Eduard Shishkin <edward6@linux.ibm.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-05-04io_uring: fix mismatched finish_wait() calls in io_uring_cancel_files()Xiaoguang Wang1-5/+4
The prepare_to_wait() and finish_wait() calls in io_uring_cancel_files() are mismatched. Currently I don't see any issues related this bug, just find it by learning codes. Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-03Merge tag 'for-5.7-rc3-tag' of ↵Linus Torvalds3-6/+52
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull more btrfs fixes from David Sterba: "A few more stability fixes, minor build warning fixes and git url fixup: - fix partial loss of prealloc extent past i_size after fsync - fix potential deadlock due to wrong transaction handle passing via journal_info - fix gcc 4.8 struct intialization warning - update git URL in MAINTAINERS entry" * tag 'for-5.7-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: MAINTAINERS: btrfs: fix git repo URL btrfs: fix gcc-4.8 build warning for struct initializer btrfs: transaction: Avoid deadlock due to bad initialization timing of fs_info::journal_info btrfs: fix partial loss of prealloc extent past i_size after fsync
2020-05-02Merge tag 'iomap-5.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2-4/+9
Pull iomap fix from Darrick Wong: "Hoist the check for an unrepresentable FIBMAP return value into ioctl_fibmap. The internal kernel function can handle 64-bit values (and is needed to fix a regression on ext4 + jbd2). It is only the userspace ioctl that is so old that it cannot deal" * tag 'iomap-5.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: fibmap: Warn and return an error in case of block > INT_MAX
2020-05-02Merge tag 'nfs-for-5.7-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds4-16/+30
Pull NFS client bugfixes from Trond Myklebust: "Highlights include: Stable fixes: - fix handling of backchannel binding in BIND_CONN_TO_SESSION Bugfixes: - Fix a credential use-after-free issue in pnfs_roc() - Fix potential posix_acl refcnt leak in nfs3_set_acl - defer slow parts of rpc_free_client() to a workqueue - Fix an Oopsable race in __nfs_list_for_each_server() - Fix trace point use-after-free race - Regression: the RDMA client no longer responds to server disconnect requests - Fix return values of xdr_stream_encode_item_{present, absent} - _pnfs_return_layout() must always wait for layoutreturn completion Cleanups: - Remove unreachable error conditions" * tag 'nfs-for-5.7-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: NFS: Fix a race in __nfs_list_for_each_server() NFSv4.1: fix handling of backchannel binding in BIND_CONN_TO_SESSION SUNRPC: defer slow parts of rpc_free_client() to a workqueue. NFSv4: Remove unreachable error condition due to rpc_run_task() SUNRPC: Remove unreachable error condition xprtrdma: Fix use of xdr_stream_encode_item_{present, absent} xprtrdma: Fix trace point use-after-free race xprtrdma: Restore wake-up-all to rpcrdma_cm_event_handler() nfs: Fix potential posix_acl refcnt leak in nfs3_set_acl NFS/pnfs: Fix a credential use-after-free issue in pnfs_roc() NFS/pnfs: Ensure that _pnfs_return_layout() waits for layoutreturn completion
2020-05-02Merge tag 'io_uring-5.7-2020-05-01' of git://git.kernel.dk/linux-blockLinus Torvalds1-27/+31
Pull io_uring fixes from Jens Axboe: - Fix for statx not grabbing the file table, making AT_EMPTY_PATH fail - Cover a few cases where async poll can handle retry, eliminating the need for an async thread - fallback request busy/free fix (Bijan) - syzbot reported SQPOLL thread exit fix for non-preempt (Xiaoguang) - Fix extra put of req for sync_file_range (Pavel) - Always punt splice async. We'll improve this for 5.8, but wanted to eliminate the inode mutex lock from the non-blocking path for 5.7 (Pavel) * tag 'io_uring-5.7-2020-05-01' of git://git.kernel.dk/linux-block: io_uring: punt splice async because of inode mutex io_uring: check non-sync defer_list carefully io_uring: fix extra put in sync_file_range() io_uring: use cond_resched() in io_ring_ctx_wait_and_kill() io_uring: use proper references for fallback_req locking io_uring: only force async punt if poll based retry can't handle it io_uring: enable poll retry for any file with ->read_iter / ->write_iter io_uring: statx must grab the file table for valid fd
2020-05-01io_uring: punt splice async because of inode mutexPavel Begunkov1-14/+2
Nonblocking do_splice() still may wait for some time on an inode mutex. Let's play safe and always punt it async. Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-01io_uring: check non-sync defer_list carefullyPavel Begunkov1-1/+1
io_req_defer() do double-checked locking. Use proper helpers for that, i.e. list_empty_careful(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-01io_uring: fix extra put in sync_file_range()Pavel Begunkov1-1/+1
[ 40.179474] refcount_t: underflow; use-after-free. [ 40.179499] WARNING: CPU: 6 PID: 1848 at lib/refcount.c:28 refcount_warn_saturate+0xae/0xf0 ... [ 40.179612] RIP: 0010:refcount_warn_saturate+0xae/0xf0 [ 40.179617] Code: 28 44 0a 01 01 e8 d7 01 c2 ff 0f 0b 5d c3 80 3d 15 44 0a 01 00 75 91 48 c7 c7 b8 f5 75 be c6 05 05 44 0a 01 01 e8 b7 01 c2 ff <0f> 0b 5d c3 80 3d f3 43 0a 01 00 0f 85 6d ff ff ff 48 c7 c7 10 f6 [ 40.179619] RSP: 0018:ffffb252423ebe18 EFLAGS: 00010286 [ 40.179623] RAX: 0000000000000000 RBX: ffff98d65e929400 RCX: 0000000000000000 [ 40.179625] RDX: 0000000000000001 RSI: 0000000000000086 RDI: 00000000ffffffff [ 40.179627] RBP: ffffb252423ebe18 R08: 0000000000000001 R09: 000000000000055d [ 40.179629] R10: 0000000000000c8c R11: 0000000000000001 R12: 0000000000000000 [ 40.179631] R13: ffff98d68c434400 R14: ffff98d6a9cbaa20 R15: ffff98d6a609ccb8 [ 40.179634] FS: 0000000000000000(0000) GS:ffff98d6af580000(0000) knlGS:0000000000000000 [ 40.179636] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 40.179638] CR2: 00000000033e3194 CR3: 000000006480a003 CR4: 00000000003606e0 [ 40.179641] Call Trace: [ 40.179652] io_put_req+0x36/0x40 [ 40.179657] io_free_work+0x15/0x20 [ 40.179661] io_worker_handle_work+0x2f5/0x480 [ 40.179667] io_wqe_worker+0x2a9/0x360 [ 40.179674] ? _raw_spin_unlock_irqrestore+0x24/0x40 [ 40.179681] kthread+0x12c/0x170 [ 40.179685] ? io_worker_handle_work+0x480/0x480 [ 40.179690] ? kthread_park+0x90/0x90 [ 40.179695] ret_from_fork+0x35/0x40 [ 40.179702] ---[ end trace 85027405f00110aa ]--- Opcode handler must never put submission ref, but that's what io_sync_file_range_finish() do. use io_steal_work() there. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-01io_uring: use cond_resched() in io_ring_ctx_wait_and_kill()Xiaoguang Wang1-1/+1
While working on to make io_uring sqpoll mode support syscalls that need struct files_struct, I got cpu soft lockup in io_ring_ctx_wait_and_kill(), while (ctx->sqo_thread && !wq_has_sleeper(&ctx->sqo_wait)) cpu_relax(); above loop never has an chance to exit, it's because preempt isn't enabled in the kernel, and the context calling io_ring_ctx_wait_and_kill() and io_sq_thread() run in the same cpu, if io_sq_thread calls a cond_resched() yield cpu and another context enters above loop, then io_sq_thread() will always in runqueue and never exit. Use cond_resched() can fix this issue. Reported-by: syzbot+66243bb7126c410cefe6@syzkaller.appspotmail.com Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-01io_uring: use proper references for fallback_req lockingBijan Mottahedeh1-2/+2
Use ctx->fallback_req address for test_and_set_bit_lock() and clear_bit_unlock(). Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-01io_uring: only force async punt if poll based retry can't handle itJens Axboe1-2/+4
We do blocking retry from our poll handler, if the file supports polled notifications. Only mark the request as needing an async worker if we can't poll for it. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-01io_uring: enable poll retry for any file with ->read_iter / ->write_iterJens Axboe1-7/+13
We can have files like eventfd where it's perfectly fine to do poll based retry on them, right now io_file_supports_async() doesn't take that into account. Pass in data direction and check the f_op instead of just always needing an async worker. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-30NFS: Fix a race in __nfs_list_for_each_server()Trond Myklebust1-1/+1
The struct nfs_server gets put on the cl_superblocks list before the server->super field has been initialised, in which case the call to nfs_sb_active() will Oops. Add a check to ensure that we skip such a list entry. Fixes: 3c9e502b59fb ("NFS: Add a helper nfs_client_for_each_server()") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-30fibmap: Warn and return an error in case of block > INT_MAXRitesh Harjani2-4/+9
We better warn the fibmap user and not return a truncated and therefore an incorrect block map address if the bmap() returned block address is greater than INT_MAX (since user supplied integer pointer). It's better to pr_warn() all user of ioctl_fibmap() and return a proper error code rather than silently letting a FS corruption happen if the user tries to fiddle around with the returned block map address. We fix this by returning an error code of -ERANGE and returning 0 as the block mapping address in case if it is > INT_MAX. Now iomap_bmap() could be called from either of these two paths. Either when a user is calling an ioctl_fibmap() interface to get the block mapping address or by some filesystem via use of bmap() internal kernel API. bmap() kernel API is well equipped with handling of u64 addresses. WARN condition in iomap_bmap_actor() was mainly added to warn all the fibmap users. But now that we have directly added this warning for all fibmap users and also made sure to return 0 as block map address in case if addr > INT_MAX. So we can now remove this logic from iomap_bmap_actor(). Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-04-30btrfs: fix gcc-4.8 build warning for struct initializerArnd Bergmann1-1/+1
Some older compilers like gcc-4.8 warn about mismatched curly braces in a initializer: fs/btrfs/backref.c: In function 'is_shared_data_backref': fs/btrfs/backref.c:394:9: error: missing braces around initializer [-Werror=missing-braces] struct prelim_ref target = {0}; ^ fs/btrfs/backref.c:394:9: error: (near initialization for 'target.rbnode') [-Werror=missing-braces] Use the GNU empty initializer extension to avoid this. Fixes: ed58f2e66e84 ("btrfs: backref, don't add refs from shared block when resolving normal backref") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-29Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds2-20/+16
Pull vfs fixes from Al Viro: "Two old bugs..." * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: propagate_one(): mnt_set_mountpoint() needs mount_lock dlmfs_file_write(): fix the bogosity in handling non-zero *ppos
2020-04-29Fix use after free in get_tree_bdev()David Howells1-1/+1
Commit 6fcf0c72e4b9, a fix to get_tree_bdev() put a missing blkdev_put() in the wrong place, before a warnf() that displays the bdev under consideration rather after it. This results in a silent lockup in printk("%pg") called via warnf() from get_tree_bdev() under some circumstances when there's a race with the blockdev being frozen. This can be caused by xfstests/tests/generic/085 in combination with Lukas Czerner's ext4 mount API conversion patchset. It looks like it ought to occur with other users of get_tree_bdev() such as XFS, but apparently doesn't. Fix this by switching the order of the lines. Fixes: 6fcf0c72e4b9 ("vfs: add missing blkdev_put() in get_tree_bdev()") Reported-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Ian Kent <raven@themaw.net> cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-28NFSv4.1: fix handling of backchannel binding in BIND_CONN_TO_SESSIONOlga Kornievskaia1-0/+8
Currently, if the client sends BIND_CONN_TO_SESSION with NFS4_CDFC4_FORE_OR_BOTH but only gets NFS4_CDFS4_FORE back it ignores that it wasn't able to enable a backchannel. To make sure, the client sends BIND_CONN_TO_SESSION as the first operation on the connections (ie., no other session compounds haven't been sent before), and if the client's request to bind the backchannel is not satisfied, then reset the connection and retry. Cc: stable@vger.kernel.org Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-28coredump: fix crash when umh is disabledLuis Chamberlain1-0/+8
Commit 64e90a8acb859 ("Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()") added the optiont to disable all call_usermodehelper() calls by setting STATIC_USERMODEHELPER_PATH to an empty string. When this is done, and crashdump is triggered, it will crash on null pointer dereference, since we make assumptions over what call_usermodehelper_exec() did. This has been reported by Sergey when one triggers a a coredump with the following configuration: ``` CONFIG_STATIC_USERMODEHELPER=y CONFIG_STATIC_USERMODEHELPER_PATH="" kernel.core_pattern = |/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h %e ``` The way disabling the umh was designed was that call_usermodehelper_exec() would just return early, without an error. But coredump assumes certain variables are set up for us when this happens, and calls ile_start_write(cprm.file) with a NULL file. [ 2.819676] BUG: kernel NULL pointer dereference, address: 0000000000000020 [ 2.819859] #PF: supervisor read access in kernel mode [ 2.820035] #PF: error_code(0x0000) - not-present page [ 2.820188] PGD 0 P4D 0 [ 2.820305] Oops: 0000 [#1] SMP PTI [ 2.820436] CPU: 2 PID: 89 Comm: a Not tainted 5.7.0-rc1+ #7 [ 2.820680] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014 [ 2.821150] RIP: 0010:do_coredump+0xd80/0x1060 [ 2.821385] Code: e8 95 11 ed ff 48 c7 c6 cc a7 b4 81 48 8d bd 28 ff ff ff 89 c2 e8 70 f1 ff ff 41 89 c2 85 c0 0f 84 72 f7 ff ff e9 b4 fe ff ff <48> 8b 57 20 0f b7 02 66 25 00 f0 66 3d 00 8 0 0f 84 9c 01 00 00 44 [ 2.822014] RSP: 0000:ffffc9000029bcb8 EFLAGS: 00010246 [ 2.822339] RAX: 0000000000000000 RBX: ffff88803f860000 RCX: 000000000000000a [ 2.822746] RDX: 0000000000000009 RSI: 0000000000000282 RDI: 0000000000000000 [ 2.823141] RBP: ffffc9000029bde8 R08: 0000000000000000 R09: ffffc9000029bc00 [ 2.823508] R10: 0000000000000001 R11: ffff88803dec90be R12: ffffffff81c39da0 [ 2.823902] R13: ffff88803de84400 R14: 0000000000000000 R15: 0000000000000000 [ 2.824285] FS: 00007fee08183540(0000) GS:ffff88803e480000(0000) knlGS:0000000000000000 [ 2.824767] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.825111] CR2: 0000000000000020 CR3: 000000003f856005 CR4: 0000000000060ea0 [ 2.825479] Call Trace: [ 2.825790] get_signal+0x11e/0x720 [ 2.826087] do_signal+0x1d/0x670 [ 2.826361] ? force_sig_info_to_task+0xc1/0xf0 [ 2.826691] ? force_sig_fault+0x3c/0x40 [ 2.826996] ? do_trap+0xc9/0x100 [ 2.827179] exit_to_usermode_loop+0x49/0x90 [ 2.827359] prepare_exit_to_usermode+0x77/0xb0 [ 2.827559] ? invalid_op+0xa/0x30 [ 2.827747] ret_from_intr+0x20/0x20 [ 2.827921] RIP: 0033:0x55e2c76d2129 [ 2.828107] Code: 2d ff ff ff e8 68 ff ff ff 5d c6 05 18 2f 00 00 01 c3 0f 1f 80 00 00 00 00 c3 0f 1f 80 00 00 00 00 e9 7b ff ff ff 55 48 89 e5 <0f> 0b b8 00 00 00 00 5d c3 66 2e 0f 1f 84 0 0 00 00 00 00 0f 1f 40 [ 2.828603] RSP: 002b:00007fffeba5e080 EFLAGS: 00010246 [ 2.828801] RAX: 000055e2c76d2125 RBX: 0000000000000000 RCX: 00007fee0817c718 [ 2.829034] RDX: 00007fffeba5e188 RSI: 00007fffeba5e178 RDI: 0000000000000001 [ 2.829257] RBP: 00007fffeba5e080 R08: 0000000000000000 R09: 00007fee08193c00 [ 2.829482] R10: 0000000000000009 R11: 0000000000000000 R12: 000055e2c76d2040 [ 2.829727] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 2.829964] CR2: 0000000000000020 [ 2.830149] ---[ end trace ceed83d8c68a1bf1 ]--- ``` Cc: <stable@vger.kernel.org> # v4.11+ Fixes: 64e90a8acb85 ("Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()") BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199795 Reported-by: Tony Vroon <chainsaw@gentoo.org> Reported-by: Sergey Kvachonok <ravenexp@gmail.com> Tested-by: Sergei Trofimovich <slyfox@gentoo.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20200416162859.26518-1-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-27Merge tag 'for-5.7-rc3-tag' of ↵Linus Torvalds4-11/+48
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - regression fixes: - transaction leak when deleting unused block group - log cleanup after transaction abort - fix block group leak when removing fails - transaction leak if relocation recovery fails - fix SPDX header * tag 'for-5.7-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix transaction leak in btrfs_recover_relocation btrfs: fix block group leak when removing fails btrfs: drop logs when we've aborted a transaction btrfs: fix memory leak of transaction when deleting unused block group btrfs: discard: Use the correct style for SPDX License Identifier
2020-04-27io_uring: statx must grab the file table for valid fdJens Axboe1-2/+10
Clay reports that OP_STATX fails for a test case with a valid fd and empty path: -- Test 0: statx:fd 3: SUCCEED, file mode 100755 -- Test 1: statx:path ./uring_statx: SUCCEED, file mode 100755 -- Test 2: io_uring_statx:fd 3: FAIL, errno 9: Bad file descriptor -- Test 3: io_uring_statx:path ./uring_statx: SUCCEED, file mode 100755 This is due to statx not grabbing the process file table, hence we can't lookup the fd in async context. If the fd is valid, ensure that we grab the file table so we can grab the file from async context. Cc: stable@vger.kernel.org # v5.6 Reported-by: Clay Harris <bugs@claycon.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-27btrfs: transaction: Avoid deadlock due to bad initialization timing of ↵Qu Wenruo1-2/+11
fs_info::journal_info [BUG] One run of btrfs/063 triggered the following lockdep warning: ============================================ WARNING: possible recursive locking detected 5.6.0-rc7-custom+ #48 Not tainted -------------------------------------------- kworker/u24:0/7 is trying to acquire lock: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs] but task is already holding lock: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sb_internal#2); lock(sb_internal#2); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by kworker/u24:0/7: #0: ffff88817b495948 ((wq_completion)btrfs-endio-write){+.+.}, at: process_one_work+0x557/0xb80 #1: ffff888189ea7db8 ((work_completion)(&work->normal_work)){+.+.}, at: process_one_work+0x557/0xb80 #2: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs] #3: ffff888174ca4da8 (&fs_info->reloc_mutex){+.+.}, at: btrfs_record_root_in_trans+0x83/0xd0 [btrfs] stack backtrace: CPU: 0 PID: 7 Comm: kworker/u24:0 Not tainted 5.6.0-rc7-custom+ #48 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Workqueue: btrfs-endio-write btrfs_work_helper [btrfs] Call Trace: dump_stack+0xc2/0x11a __lock_acquire.cold+0xce/0x214 lock_acquire+0xe6/0x210 __sb_start_write+0x14e/0x290 start_transaction+0x66c/0x890 [btrfs] btrfs_join_transaction+0x1d/0x20 [btrfs] find_free_extent+0x1504/0x1a50 [btrfs] btrfs_reserve_extent+0xd5/0x1f0 [btrfs] btrfs_alloc_tree_block+0x1ac/0x570 [btrfs] btrfs_copy_root+0x213/0x580 [btrfs] create_reloc_root+0x3bd/0x470 [btrfs] btrfs_init_reloc_root+0x2d2/0x310 [btrfs] record_root_in_trans+0x191/0x1d0 [btrfs] btrfs_record_root_in_trans+0x90/0xd0 [btrfs] start_transaction+0x16e/0x890 [btrfs] btrfs_join_transaction+0x1d/0x20 [btrfs] btrfs_finish_ordered_io+0x55d/0xcd0 [btrfs] finish_ordered_fn+0x15/0x20 [btrfs] btrfs_work_helper+0x116/0x9a0 [btrfs] process_one_work+0x632/0xb80 worker_thread+0x80/0x690 kthread+0x1a3/0x1f0 ret_from_fork+0x27/0x50 It's pretty hard to reproduce, only one hit so far. [CAUSE] This is because we're calling btrfs_join_transaction() without re-using the current running one: btrfs_finish_ordered_io() |- btrfs_join_transaction() <<< Call #1 |- btrfs_record_root_in_trans() |- btrfs_reserve_extent() |- btrfs_join_transaction() <<< Call #2 Normally such btrfs_join_transaction() call should re-use the existing one, without trying to re-start a transaction. But the problem is, in btrfs_join_transaction() call #1, we call btrfs_record_root_in_trans() before initializing current::journal_info. And in btrfs_join_transaction() call #2, we're relying on current::journal_info to avoid such deadlock. [FIX] Call btrfs_record_root_in_trans() after we have initialized current::journal_info. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-27btrfs: fix partial loss of prealloc extent past i_size after fsyncFilipe Manana1-3/+40
When we have an inode with a prealloc extent that starts at an offset lower than the i_size and there is another prealloc extent that starts at an offset beyond i_size, we can end up losing part of the first prealloc extent (the part that starts at i_size) and have an implicit hole if we fsync the file and then have a power failure. Consider the following example with comments explaining how and why it happens. $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt # Create our test file with 2 consecutive prealloc extents, each with a # size of 128Kb, and covering the range from 0 to 256Kb, with a file # size of 0. $ xfs_io -f -c "falloc -k 0 128K" /mnt/foo $ xfs_io -c "falloc -k 128K 128K" /mnt/foo # Fsync the file to record both extents in the log tree. $ xfs_io -c "fsync" /mnt/foo # Now do a redudant extent allocation for the range from 0 to 64Kb. # This will merely increase the file size from 0 to 64Kb. Instead we # could also do a truncate to set the file size to 64Kb. $ xfs_io -c "falloc 0 64K" /mnt/foo # Fsync the file, so we update the inode item in the log tree with the # new file size (64Kb). This also ends up setting the number of bytes # for the first prealloc extent to 64Kb. This is done by the truncation # at btrfs_log_prealloc_extents(). # This means that if a power failure happens after this, a write into # the file range 64Kb to 128Kb will not use the prealloc extent and # will result in allocation of a new extent. $ xfs_io -c "fsync" /mnt/foo # Now set the file size to 256K with a truncate and then fsync the file. # Since no changes happened to the extents, the fsync only updates the # i_size in the inode item at the log tree. This results in an implicit # hole for the file range from 64Kb to 128Kb, something which fsck will # complain when not using the NO_HOLES feature if we replay the log # after a power failure. $ xfs_io -c "truncate 256K" -c "fsync" /mnt/foo So instead of always truncating the log to the inode's current i_size at btrfs_log_prealloc_extents(), check first if there's a prealloc extent that starts at an offset lower than the i_size and with a length that crosses the i_size - if there is one, just make sure we truncate to a size that corresponds to the end offset of that prealloc extent, so that we don't lose the part of that extent that starts at i_size if a power failure happens. A test case for fstests follows soon. Fixes: 31d11b83b96f ("Btrfs: fix duplicate extents after fsync of file with prealloc extents") CC: stable@vger.kernel.org # 4.14+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-27propagate_one(): mnt_set_mountpoint() needs mount_lockAl Viro1-5/+4
... to protect the modification of mp->m_count done by it. Most of the places that modify that thing also have namespace_lock held, but not all of them can do so, so we really need mount_lock here. Kudos to Piotr Krysiuk <piotras@gmail.com>, who'd spotted a related bug in pivot_root(2) (fixed unnoticed in 5.3); search for other similar turds has caught out this one. Cc: stable@kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-27configfs: fix config_item refcnt leak in configfs_rmdir()Xiyu Yang1-0/+1
configfs_rmdir() invokes configfs_get_config_item(), which returns a reference of the specified config_item object to "parent_item" with increased refcnt. When configfs_rmdir() returns, local variable "parent_item" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of configfs_rmdir(). When down_write_killable() fails, the function forgets to decrease the refcnt increased by configfs_get_config_item(), causing a refcnt leak. Fix this issue by calling config_item_put() when down_write_killable() fails. Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-26Merge tag '5.7-rc2-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds4-18/+78
Pull cifs fixes from Steve French: "Five cifs/smb3 fixes:two for DFS reconnect failover, one lease fix for stable and the others to fix a missing spinlock during reconnect" * tag '5.7-rc2-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: fix uninitialised lease_key in open_shroot() cifs: ensure correct super block for DFS reconnect cifs: do not share tcons with DFS cifs: minor update to comments around the cifs_tcp_ses_lock mutex cifs: protect updating server->dstaddr with a spinlock
2020-04-26Merge tag 'driver-core-5.7-rc3' of ↵Linus Torvalds1-12/+3
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core fixes from Greg KH: "Here are some small firmware/driver core/debugfs fixes for 5.7-rc3. The debugfs change is now possible as now the last users of debugfs_create_u32() have been fixed up in the different trees that got merged into 5.7-rc1, and I don't want it creeping back in. The firmware changes did cause a regression in linux-next, so the final patch here reverts part of that, re-exporting the symbol to resolve that issue. All of these patches, with the exception of the final one, have been in linux-next with only that one reported issue" * tag 'driver-core-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: firmware_loader: revert removal of the fw_fallback_config export debugfs: remove return value of debugfs_create_u32() firmware_loader: remove unused exports firmware: imx: fix compile-testing
2020-04-25Merge branch 'for-linus' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull pid leak fix from Eric Biederman: "Oleg noticed that put_pid(thread_pid) was not getting called when proc was not compiled in. Let's get that fixed before 5.7 is released and causes problems for anyone" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: proc: Put thread_pid in release_task not proc_flush_pid
2020-04-25NFSv4: Remove unreachable error condition due to rpc_run_task()Xiyu Yang1-2/+1
nfs4_proc_layoutget() invokes rpc_run_task(), which return the value to "task". Since rpc_run_task() is impossible to return an ERR pointer, there is no need to add the IS_ERR() condition on "task" here. So we need to remove it. Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-24proc: Put thread_pid in release_task not proc_flush_pidEric W. Biederman1-1/+0
Oleg pointed out that in the unlikely event the kernel is compiled with CONFIG_PROC_FS unset that release_task will now leak the pid. Move the put_pid out of proc_flush_pid into release_task to fix this and to guarantee I don't make that mistake again. When possible it makes sense to keep get and put in the same function so it can easily been seen how they pair up. Fixes: 7bc3e6e55acf ("proc: Use a list of inodes to flush from proc") Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-04-24Merge tag 'io_uring-5.7-2020-04-24' of git://git.kernel.dk/linux-blockLinus Torvalds1-5/+5
Pull io_uring fix from Jens Axboe: "Single fixup for a change that went into -rc2" * tag 'io_uring-5.7-2020-04-24' of git://git.kernel.dk/linux-block: io_uring: only restore req->work for req that needs do completion
2020-04-24Merge tag 'block-5.7-2020-04-24' of git://git.kernel.dk/linux-blockLinus Torvalds2-2/+11
Pull block fixes from Jens Axboe: "A few fixes/changes that should go into this release: - null_blk zoned fixes (Damien) - blkdev_close() sync improvement (Douglas) - Fix regression in blk-iocost that impacted (at least) systemtap (Waiman) - Comment fix, header removal (Zhiqiang, Jianpeng)" * tag 'block-5.7-2020-04-24' of git://git.kernel.dk/linux-block: null_blk: Cleanup zoned device initialization null_blk: Fix zoned command handling block: remove unused header blk-iocost: Fix error on iocost_ioc_vrate_adj bdev: Reduce time holding bd_mutex in sync in blkdev_close() buffer: remove useless comment and WB_REASON_FREE_MORE_MEM, reason.
2020-04-24Merge tag 'afs-fixes-20200424' of ↵Linus Torvalds7-21/+15
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull misc AFS fixes from David Howells: "Three miscellaneous fixes to the afs filesystem: - Remove some struct members that aren't used, aren't set or aren't read, plus a wake up that nothing ever waits for. - Actually set the AFS_SERVER_FL_HAVE_EPOCH flag so that the code that depends on it can work. - Make a couple of waits uninterruptible if they're done for an operation that isn't supposed to be interruptible" * tag 'afs-fixes-20200424' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: afs: Make record checking use TASK_UNINTERRUPTIBLE when appropriate afs: Fix to actually set AFS_SERVER_FL_HAVE_EPOCH afs: Remove some unused bits