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If the delegation has been revoked, ignore it.
Signed-off-by: Trond Myklebust <[email protected]>
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If the delegation is marked as being revoked, then don't use it in
the open state structure.
Signed-off-by: Trond Myklebust <[email protected]>
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NFSv2, v3 and NFSv4 servers often have duplicate replay caches that look
at the source port when deciding whether or not an RPC call is a replay
of a previous call. This requires clients to perform strange TCP gymnastics
in order to ensure that when they reconnect to the server, they bind
to the same source port.
NFSv4.1 and NFSv4.2 have sessions that provide proper replay semantics,
that do not look at the source port of the connection. This patch therefore
ensures they can ignore the rebind requirement.
Signed-off-by: Trond Myklebust <[email protected]>
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If a NFSv3 server is being used as both a DS and as a regular NFSv3 server,
we may want to keep the IO traffic on a separate TCP connection, since
it will typically have very different timeout characteristics.
This patch therefore sets up a flag to separate the two modes of operation
for the nfs_client.
Signed-off-by: Trond Myklebust <[email protected]>
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Connecting to the DS is a non-interactive, asynchronous task, so there is
no reason to fire up an extra RPC null ping in order to ensure that the
server is up.
Signed-off-by: Trond Myklebust <[email protected]>
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Add a flag to tell the nfs_client it should set RPC_CLNT_CREATE_NOPING when
creating the rpc client.
Signed-off-by: Trond Myklebust <[email protected]>
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We don't need atomic bit ops when initialising a local structure on the
stack.
Signed-off-by: Trond Myklebust <[email protected]>
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Simplify the struct iattr timestamp encoding by skipping the step of
an intermediate struct timespec.
Signed-off-by: Trond Myklebust <[email protected]>
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Simplify the struct iattr timestamp encoding by skipping the step of
an intermediate struct timespec.
Signed-off-by: Trond Myklebust <[email protected]>
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Encode the mtime correctly.
Fixes: 95582b0083883 ("vfs: change inode times to use struct timespec64")
Signed-off-by: Trond Myklebust <[email protected]>
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Convert the NFSv4 callbacks to use struct timestamp64, rather than
truncating times to 32-bit values.
Signed-off-by: Trond Myklebust <[email protected]>
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NFSv4 supports 64-bit timestamps, so there is no point in converting
the struct iattr timestamps to 32-bits before encoding.
Signed-off-by: Trond Myklebust <[email protected]>
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NFSv4 supports 64-bit times, so we should switch to using struct
timespec64 when decoding attributes.
Signed-off-by: Trond Myklebust <[email protected]>
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If we set nfs_mountpoint_expiry_timeout to a negative value, then
allow that to imply that we do not expire NFSv4 submounts.
Signed-off-by: Trond Myklebust <[email protected]>
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Pull cifs fix from Steve French:
"A small smb3 memleak fix"
* tag '5.4-rc6-smb3-fix' of git://git.samba.org/sfrench/cifs-2.6:
fix memory leak in large read decrypt offload
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Pull NFS client bugfixes from Anna Schumaker:
"This contains two delegation fixes (with the RCU lock leak fix marked
for stable), and three patches to fix destroying the the sunrpc back
channel.
Stable bugfixes:
- Fix an RCU lock leak in nfs4_refresh_delegation_stateid()
Other fixes:
- The TCP back channel mustn't disappear while requests are
outstanding
- The RDMA back channel mustn't disappear while requests are
outstanding
- Destroy the back channel when we destroy the host transport
- Don't allow a cached open with a revoked delegation"
* tag 'nfs-for-5.4-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
NFS: Fix an RCU lock leak in nfs4_refresh_delegation_stateid()
NFSv4: Don't allow a cached open with a revoked delegation
SUNRPC: Destroy the back channel when we destroy the host transport
SUNRPC: The RDMA back channel mustn't disappear while requests are outstanding
SUNRPC: The TCP back channel mustn't disappear while requests are outstanding
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Pull block fixes from Jens Axboe:
- Two small nvme fixes, one is a fabrics connection fix, the other one
a cleanup made possible by that fix (Anton, via Keith)
- Fix requeue handling in umb ubd (Anton)
- Fix spin_lock_irq() nesting in blk-iocost (Dan)
- Three small io_uring fixes:
- Install io_uring fd after done with ctx (me)
- Clear ->result before every poll issue (me)
- Fix leak of shadow request on error (Pavel)
* tag 'for-linus-20191101' of git://git.kernel.dk/linux-block:
iocost: don't nest spin_lock_irq in ioc_weight_write()
io_uring: ensure we clear io_kiocb->result before each issue
um-ubd: Entrust re-queue to the upper layers
nvme-multipath: remove unused groups_only mode in ana log
nvme-multipath: fix possible io hang after ctrl reconnect
io_uring: don't touch ctx in setup after ring fd install
io_uring: Fix leaked shadow_req
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A typo in nfs4_refresh_delegation_stateid() means we're leaking an
RCU lock, and always returning a value of 'false'. As the function
description states, we were always supposed to return 'true' if a
matching delegation was found.
Fixes: 12f275cdd163 ("NFSv4: Retry CLOSE and DELEGRETURN on NFS4ERR_OLD_STATEID.")
Cc: [email protected] # v4.15+
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>
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If the delegation is marked as being revoked, we must not use it
for cached opens.
Fixes: 869f9dfa4d6d ("NFSv4: Fix races between nfs_remove_bad_delegation() and delegation return")
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>
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We use io_kiocb->result == -EAGAIN as a way to know if we need to
re-submit a polled request, as -EAGAIN reporting happens out-of-line
for IO submission failures. This field is cleared when we originally
allocate the request, but it isn't reset when we retry the submission
from async context. This can cause issues where we think something
needs a re-issue, but we're really just reading stale data.
Reset ->result whenever we re-prep a request for polled submission.
Cc: [email protected]
Fixes: 9e645e1105ca ("io_uring: add support for sqe links")
Reported-by: Bijan Mottahedeh <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 fix from Andreas Gruenbacher:
"Fix remounting (broken in -rc1)."
* tag 'gfs2-v5.4-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: Fix initialisation of args for remount
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When gfs2 was converted to use fs_context, the initialisation of the
mount args structure to the currently active args was lost with the
removal of gfs2_remount_fs(), so the checks of the new args on remount
became checks against the default values instead of the current ones.
This caused unexpected remount behaviour and test failures (xfstests
generic/294, generic/306 and generic/452).
Reinstate the args initialisation, this time in gfs2_init_fs_context()
and conditional upon fc->purpose, as that's the only time we get control
before the mount args are parsed in the remount process.
Fixes: 1f52aa08d12f ("gfs2: Convert gfs2 to fs_context")
Signed-off-by: Andrew Price <[email protected]>
Signed-off-by: Andreas Gruenbacher <[email protected]>
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git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
"Mostly virtiofs fixes, but also fixes a regression and couple of
longstanding data/metadata writeback ordering issues"
* tag 'fuse-fixes-5.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: redundant get_fuse_inode() calls in fuse_writepages_fill()
fuse: Add changelog entries for protocols 7.1 - 7.8
fuse: truncate pending writes on O_TRUNC
fuse: flush dirty data/metadata before non-truncate setattr
virtiofs: Remove set but not used variable 'fc'
virtiofs: Retry request submission from worker context
virtiofs: Count pending forgets as in_flight forgets
virtiofs: Set FR_SENT flag only after request has been sent
virtiofs: No need to check fpq->connected state
virtiofs: Do not end request in submission context
fuse: don't advise readdirplus for negative lookup
fuse: don't dereference req->args on finished request
virtio-fs: don't show mount options
virtio-fs: Change module name to virtiofs.ko
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syzkaller reported an issue where it looks like a malicious app can
trigger a use-after-free of reading the ctx ->sq_array and ->rings
value right after having installed the ring fd in the process file
table.
Defer ring fd installation until after we're done reading those
values.
Fixes: 75b28affdd6a ("io_uring: allocate the two rings together")
Reported-by: [email protected]
Signed-off-by: Jens Axboe <[email protected]>
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io_queue_link_head() owns shadow_req after taking it as an argument.
By not freeing it in case of an error, it can leak the request along
with taken ctx->refs.
Reviewed-by: Jackie Liu <[email protected]>
Signed-off-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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Spotted by Ronnie.
Reviewed-by: Ronnie Sahlberg <[email protected]>
Signed-off-by: Steve French <[email protected]>
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Pull cifs fixes from Steve French:
"Seven cifs/smb3 fixes, including three for stable"
* tag '5.4-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: Fix cifsInodeInfo lock_sem deadlock when reconnect occurs
CIFS: Fix use after free of file info structures
CIFS: Fix retry mid list corruption on reconnects
cifs: Fix missed free operations
CIFS: avoid using MID 0xFFFF
cifs: clarify comment about timestamp granularity for old servers
cifs: Handle -EINPROGRESS only when noblockcnt is set
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Pull block and io_uring fixes from Jens Axboe:
"A bit bigger than usual at this point in time, mostly due to some good
bug hunting work by Pavel that resulted in three io_uring fixes from
him and two from me. Anyway, this pull request contains:
- Revert of the submit-and-wait optimization for io_uring, it can't
always be done safely. It depends on commands always making
progress on their own, which isn't necessarily the case outside of
strict file IO. (me)
- Series of two patches from me and three from Pavel, fixing issues
with shared data and sequencing for io_uring.
- Lastly, two timeout sequence fixes for io_uring (zhangyi)
- Two nbd patches fixing races (Josef)
- libahci regulator_get_optional() fix (Mark)"
* tag 'for-linus-2019-10-26' of git://git.kernel.dk/linux-block:
nbd: verify socket is supported during setup
ata: libahci_platform: Fix regulator_get_optional() misuse
nbd: handle racing with error'ed out commands
nbd: protect cmd->status with cmd->lock
io_uring: fix bad inflight accounting for SETUP_IOPOLL|SETUP_SQTHREAD
io_uring: used cached copies of sq->dropped and cq->overflow
io_uring: Fix race for sqes with userspace
io_uring: Fix broken links with offloading
io_uring: Fix corrupted user_data
io_uring: correct timeout req sequence when inserting a new entry
io_uring : correct timeout req sequence when waiting timeout
io_uring: revert "io_uring: optimize submit_and_wait API"
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git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull dax fix from Dan Williams:
"Fix a performance regression that followed from a fix to the
conversion of the fsdax implementation to the xarray. v5.3 users
report that they stop seeing huge page mappings on an application +
filesystem layout that was seeing huge pages previously on v5.2"
* tag 'dax-fix-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
fs/dax: Fix pmd vs pte conflict detection
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We currently assume that submissions from the sqthread are successful,
and if IO polling is enabled, we use that value for knowing how many
completions to look for. But if we overflowed the CQ ring or some
requests simply got errored and already completed, they won't be
available for polling.
For the case of IO polling and SQTHREAD usage, look at the pending
poll list. If it ever hits empty then we know that we don't have
anymore pollable requests inflight. For that case, simply reset
the inflight count to zero.
Reported-by: Pavel Begunkov <[email protected]>
Reviewed-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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We currently use the ring values directly, but that can lead to issues
if the application is malicious and changes these values on our behalf.
Created in-kernel cached versions of them, and just overwrite the user
side when we update them. This is similar to how we treat the sq/cq
ring tail/head updates.
Reported-by: Pavel Begunkov <[email protected]>
Reviewed-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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io_ring_submit() finalises with
1. io_commit_sqring(), which releases sqes to the userspace
2. Then calls to io_queue_link_head(), accessing released head's sqe
Reorder them.
Signed-off-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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io_sq_thread() processes sqes by 8 without considering links. As a
result, links will be randomely subdivided.
The easiest way to fix it is to call io_get_sqring() inside
io_submit_sqes() as do io_ring_submit().
Downsides:
1. This removes optimisation of not grabbing mm_struct for fixed files
2. It submitting all sqes in one go, without finer-grained sheduling
with cq processing.
Signed-off-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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There is a bug, where failed linked requests are returned not with
specified @user_data, but with garbage from a kernel stack.
The reason is that io_fail_links() uses req->user_data, which is
uninitialised when called from io_queue_sqe() on fail path.
Signed-off-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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There's a deadlock that is possible and can easily be seen with
a test where multiple readers open/read/close of the same file
and a disruption occurs causing reconnect. The deadlock is due
a reader thread inside cifs_strict_readv calling down_read and
obtaining lock_sem, and then after reconnect inside
cifs_reopen_file calling down_read a second time. If in
between the two down_read calls, a down_write comes from
another process, deadlock occurs.
CPU0 CPU1
---- ----
cifs_strict_readv()
down_read(&cifsi->lock_sem);
_cifsFileInfo_put
OR
cifs_new_fileinfo
down_write(&cifsi->lock_sem);
cifs_reopen_file()
down_read(&cifsi->lock_sem);
Fix the above by changing all down_write(lock_sem) calls to
down_write_trylock(lock_sem)/msleep() loop, which in turn
makes the second down_read call benign since it will never
block behind the writer while holding lock_sem.
Signed-off-by: Dave Wysochanski <[email protected]>
Suggested-by: Ronnie Sahlberg <[email protected]>
Reviewed--by: Ronnie Sahlberg <[email protected]>
Reviewed-by: Pavel Shilovsky <[email protected]>
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Currently the code assumes that if a file info entry belongs
to lists of open file handles of an inode and a tcon then
it has non-zero reference. The recent changes broke that
assumption when putting the last reference of the file info.
There may be a situation when a file is being deleted but
nothing prevents another thread to reference it again
and start using it. This happens because we do not hold
the inode list lock while checking the number of references
of the file info structure. Fix this by doing the proper
locking when doing the check.
Fixes: 487317c99477d ("cifs: add spinlock for the openFileList to cifsInodeInfo")
Fixes: cb248819d209d ("cifs: use cifsInodeInfo->open_file_lock while iterating to avoid a panic")
Cc: Stable <[email protected]>
Reviewed-by: Ronnie Sahlberg <[email protected]>
Signed-off-by: Pavel Shilovsky <[email protected]>
Signed-off-by: Steve French <[email protected]>
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When the client hits reconnect it iterates over the mid
pending queue marking entries for retry and moving them
to a temporary list to issue callbacks later without holding
GlobalMid_Lock. In the same time there is no guarantee that
mids can't be removed from the temporary list or even
freed completely by another thread. It may cause a temporary
list corruption:
[ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469
[ 430.464668] ------------[ cut here ]------------
[ 430.466569] kernel BUG at lib/list_debug.c:51!
[ 430.468476] invalid opcode: 0000 [#1] SMP PTI
[ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19
[ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55
...
[ 430.510426] Call Trace:
[ 430.511500] cifs_reconnect+0x25e/0x610 [cifs]
[ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs]
[ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs]
[ 430.517452] ? try_to_wake_up+0x212/0x650
[ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs]
[ 430.521086] ? allocate_buffers+0x66/0x120 [cifs]
[ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs]
[ 430.525116] kthread+0xfb/0x130
[ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs]
[ 430.528514] ? kthread_park+0x90/0x90
[ 430.530019] ret_from_fork+0x35/0x40
Fix this by obtaining extra references for mids being retried
and marking them as MID_DELETED which indicates that such a mid
has been dequeued from the pending list.
Also move mid cleanup logic from DeleteMidQEntry to
_cifs_mid_q_entry_release which is called when the last reference
to a particular mid is put. This allows to avoid any use-after-free
of response buffers.
The patch needs to be backported to stable kernels. A stable tag
is not mentioned below because the patch doesn't apply cleanly
to any actively maintained stable kernel.
Reviewed-by: Ronnie Sahlberg <[email protected]>
Reviewed-and-tested-by: David Wysochanski <[email protected]>
Signed-off-by: Pavel Shilovsky <[email protected]>
Signed-off-by: Steve French <[email protected]>
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git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 fix from Andreas Gruenbacher:
"Fix a memory leak introduced in -rc1"
* tag 'gfs2-v5.4-rc4.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: Fix memory leak when gfs2meta's fs_context is freed
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gfs2 and gfs2meta share an ->init_fs_context function which allocates an
args structure stored in fc->fs_private. gfs2 registers a ->free
function to free this memory when the fs_context is cleaned up, but
there was not one registered for gfs2meta, causing a leak.
Register a ->free function for gfs2meta. The existing gfs2_fc_free
function does what we need.
Reported-by: [email protected]
Fixes: 1f52aa08d12f ("gfs2: Convert gfs2 to fs_context")
Signed-off-by: Andrew Price <[email protected]>
Signed-off-by: Bob Peterson <[email protected]>
Signed-off-by: Andreas Gruenbacher <[email protected]>
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The sequence number of the timeout req (req->sequence) indicate the
expected completion request. Because of each timeout req consume a
sequence number, so the sequence of each timeout req on the timeout
list shouldn't be the same. But now, we may get the same number (also
incorrect) if we insert a new entry before the last one, such as submit
such two timeout reqs on a new ring instance below.
req->sequence
req_1 (count = 2): 2
req_2 (count = 1): 2
Then, if we submit a nop req, req_2 will still timeout even the nop req
finished. This patch fix this problem by adjust the sequence number of
each reordered reqs when inserting a new entry.
Signed-off-by: zhangyi (F) <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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The sequence number of reqs on the timeout_list before the timeout req
should be adjusted in io_timeout_fn(), because the current timeout req
will consumes a slot in the cq_ring and cq_tail pointer will be
increased, otherwise other timeout reqs may return in advance without
waiting for enough wait_nr.
Signed-off-by: zhangyi (F) <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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There are cases where it isn't always safe to block for submission,
even if the caller asked to wait for events as well. Revert the
previous optimization of doing that.
This reverts two commits:
bf7ec93c644cb
c576666863b78
Fixes: c576666863b78 ("io_uring: optimize submit_and_wait API")
Signed-off-by: Jens Axboe <[email protected]>
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Currently fuse_writepages_fill() calls get_fuse_inode() few times with
the same argument.
Signed-off-by: Vasily Averin <[email protected]>
Signed-off-by: Miklos Szeredi <[email protected]>
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Make sure cached writes are not reordered around open(..., O_TRUNC), with
the obvious wrong results.
Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on")
Cc: <[email protected]> # v3.15+
Signed-off-by: Miklos Szeredi <[email protected]>
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If writeback cache is enabled, then writes might get reordered with
chmod/chown/utimes. The problem with this is that performing the write in
the fuse daemon might itself change some of these attributes. In such case
the following sequence of operations will result in file ending up with the
wrong mode, for example:
int fd = open ("suid", O_WRONLY|O_CREAT|O_EXCL);
write (fd, "1", 1);
fchown (fd, 0, 0);
fchmod (fd, 04755);
close (fd);
This patch fixes this by flushing pending writes before performing
chown/chmod/utimes.
Reported-by: Giuseppe Scrivano <[email protected]>
Tested-by: Giuseppe Scrivano <[email protected]>
Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on")
Cc: <[email protected]> # v3.15+
Signed-off-by: Miklos Szeredi <[email protected]>
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- fixes of error handling cleanup of metadata accounting with qgroups
enabled
- fix swapped values for qgroup tracepoints
- fix race when handling full sync flag
- don't start unused worker thread, functionality removed already
* tag 'for-5.4-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: check for the full sync flag while holding the inode lock during fsync
Btrfs: fix qgroup double free after failure to reserve metadata for delalloc
btrfs: tracepoints: Fix bad entry members of qgroup events
btrfs: tracepoints: Fix wrong parameter order for qgroup events
btrfs: qgroup: Always free PREALLOC META reserve in btrfs_delalloc_release_extents()
btrfs: don't needlessly create extent-refs kernel thread
btrfs: block-group: Fix a memory leak due to missing btrfs_put_block_group()
Btrfs: add missing extents release on file extent cluster relocation error
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Fixes gcc '-Wunused-but-set-variable' warning:
fs/fuse/virtio_fs.c: In function virtio_fs_wake_pending_and_unlock:
fs/fuse/virtio_fs.c:983:20: warning: variable fc set but not used [-Wunused-but-set-variable]
It is not used since commit 7ee1e2e631db ("virtiofs: No need to check
fpq->connected state")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: zhengbin <[email protected]>
Signed-off-by: Miklos Szeredi <[email protected]>
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Users reported a v5.3 performance regression and inability to establish
huge page mappings. A revised version of the ndctl "dax.sh" huge page
unit test identifies commit 23c84eb78375 "dax: Fix missed wakeup with
PMD faults" as the source.
Update get_unlocked_entry() to check for NULL entries before checking
the entry order, otherwise NULL is misinterpreted as a present pte
conflict. The 'order' check needs to happen before the locked check as
an unlocked entry at the wrong order must fallback to lookup the correct
order.
Reported-by: Jeff Smits <[email protected]>
Reported-by: Doug Nelson <[email protected]>
Cc: <[email protected]>
Fixes: 23c84eb78375 ("dax: Fix missed wakeup with PMD faults")
Reviewed-by: Jan Kara <[email protected]>
Cc: Jeff Moyer <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Reviewed-by: Johannes Thumshirn <[email protected]>
Link: https://lore.kernel.org/r/157167532455.3945484.11971474077040503994.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <[email protected]>
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If regular request queue gets full, currently we sleep for a bit and
retrying submission in submitter's context. This assumes submitter is not
holding any spin lock. But this assumption is not true for background
requests. For background requests, we are called with fc->bg_lock held.
This can lead to deadlock where one thread is trying submission with
fc->bg_lock held while request completion thread has called
fuse_request_end() which tries to acquire fc->bg_lock and gets blocked. As
request completion thread gets blocked, it does not make further progress
and that means queue does not get empty and submitter can't submit more
requests.
To solve this issue, retry submission with the help of a worker, instead of
retrying in submitter's context. We already do this for hiprio/forget
requests.
Reported-by: Chirantan Ekbote <[email protected]>
Signed-off-by: Vivek Goyal <[email protected]>
Signed-off-by: Miklos Szeredi <[email protected]>
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If virtqueue is full, we put forget requests on a list and these forgets
are dispatched later using a worker. As of now we don't count these forgets
in fsvq->in_flight variable. This means when queue is being drained, we
have to have special logic to first drain these pending requests and then
wait for fsvq->in_flight to go to zero.
By counting pending forgets in fsvq->in_flight, we can get rid of special
logic and just wait for in_flight to go to zero. Worker thread will kick
and drain all the forgets anyway, leading in_flight to zero.
I also need similar logic for normal request queue in next patch where I am
about to defer request submission in the worker context if queue is full.
This simplifies the code a bit.
Also add two helper functions to inc/dec in_flight. Decrement in_flight
helper will later used to call completion when in_flight reaches zero.
Signed-off-by: Vivek Goyal <[email protected]>
Signed-off-by: Miklos Szeredi <[email protected]>
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