Merge tag 'v6.6.51' into for/openbmc/dev-6.6

This is the 6.6.51 stable release

btrfs: fix race between direct IO write and fsync when using same fd

commit cd9253c23aedd61eb5ff11f37a36247cd46faf86 upstream.

If we have 2 threads that are using the same file descriptor and one o

btrfs: fix race between direct IO write and fsync when using same fd

commit cd9253c23aedd61eb5ff11f37a36247cd46faf86 upstream.

If we have 2 threads that are using the same file descriptor and one of
them is doing direct IO writes while the other is doing fsync, we have a
race where we can end up either:

1) Attempt a fsync without holding the inode's lock, triggering an
assertion failures when assertions are enabled;

2) Do an invalid memory access from the fsync task because the file private
points to memory allocated on stack by the direct IO task and it may be
used by the fsync task after the stack was destroyed.

The race happens like this:

1) A user space program opens a file descriptor with O_DIRECT;

2) The program spawns 2 threads using libpthread for example;

3) One of the threads uses the file descriptor to do direct IO writes,
while the other calls fsync using the same file descriptor.

4) Call task A the thread doing direct IO writes and task B the thread
doing fsyncs;

5) Task A does a direct IO write, and at btrfs_direct_write() sets the
file's private to an on stack allocated private with the member
'fsync_skip_inode_lock' set to true;

6) Task B enters btrfs_sync_file() and sees that there's a private
structure associated to the file which has 'fsync_skip_inode_lock' set
to true, so it skips locking the inode's VFS lock;

7) Task A completes the direct IO write, and resets the file's private to
NULL since it had no prior private and our private was stack allocated.
Then it unlocks the inode's VFS lock;

8) Task B enters btrfs_get_ordered_extents_for_logging(), then the
assertion that checks the inode's VFS lock is held fails, since task B
never locked it and task A has already unlocked it.

The stack trace produced is the following:

assertion failed: inode_is_locked(&inode->vfs_inode), in fs/btrfs/ordered-data.c:983
------------[ cut here ]------------
kernel BUG at fs/btrfs/ordered-data.c:983!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 9 PID: 5072 Comm: worker Tainted: G U OE 6.10.5-1-default #1 openSUSE Tumbleweed 69f48d427608e1c09e60ea24c6c55e2ca1b049e8
Hardware name: Acer Predator PH315-52/Covini_CFS, BIOS V1.12 07/28/2020
RIP: 0010:btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs]
Code: 50 d6 86 c0 e8 (...)
RSP: 0018:ffff9e4a03dcfc78 EFLAGS: 00010246
RAX: 0000000000000054 RBX: ffff9078a9868e98 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff907dce4a7800 RDI: ffff907dce4a7800
RBP: ffff907805518800 R08: 0000000000000000 R09: ffff9e4a03dcfb38
R10: ffff9e4a03dcfb30 R11: 0000000000000003 R12: ffff907684ae7800
R13: 0000000000000001 R14: ffff90774646b600 R15: 0000000000000000
FS: 00007f04b96006c0(0000) GS:ffff907dce480000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f32acbfc000 CR3: 00000001fd4fa005 CR4: 00000000003726f0
Call Trace:
<TASK>
? __die_body.cold+0x14/0x24
? die+0x2e/0x50
? do_trap+0xca/0x110
? do_error_trap+0x6a/0x90
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? exc_invalid_op+0x50/0x70
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? asm_exc_invalid_op+0x1a/0x20
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
btrfs_sync_file+0x21a/0x4d0 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? __seccomp_filter+0x31d/0x4f0
__x64_sys_fdatasync+0x4f/0x90
do_syscall_64+0x82/0x160
? do_futex+0xcb/0x190
? __x64_sys_futex+0x10e/0x1d0
? switch_fpu_return+0x4f/0xd0
? syscall_exit_to_user_mode+0x72/0x220
? do_syscall_64+0x8e/0x160
? syscall_exit_to_user_mode+0x72/0x220
? do_syscall_64+0x8e/0x160
? syscall_exit_to_user_mode+0x72/0x220
? do_syscall_64+0x8e/0x160
? syscall_exit_to_user_mode+0x72/0x220
? do_syscall_64+0x8e/0x160
entry_SYSCALL_64_after_hwframe+0x76/0x7e

Another problem here is if task B grabs the private pointer and then uses
it after task A has finished, since the private was allocated in the stack
of task A, it results in some invalid memory access with a hard to predict
result.

This issue, triggering the assertion, was observed with QEMU workloads by
two users in the Link tags below.

Fix this by not relying on a file's private to pass information to fsync
that it should skip locking the inode and instead pass this information
through a special value stored in current->journal_info. This is safe
because in the relevant section of the direct IO write path we are not
holding a transaction handle, so current->journal_info is NULL.

The following C program triggers the issue:

$ cat repro.c
/* Get the O_DIRECT definition. */
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdint.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <pthread.h>

static int fd;

static ssize_t do_write(int fd, const void *buf, size_t count, off_t offset)
{
while (count > 0) {
ssize_t ret;

ret = pwrite(fd, buf, count, offset);
if (ret < 0) {
if (errno == EINTR)
continue;
return ret;
}
count -= ret;
buf += ret;
}
return 0;
}

static void *fsync_loop(void *arg)
{
while (1) {
int ret;

ret = fsync(fd);
if (ret != 0) {
perror("Fsync failed");
exit(6);
}
}
}

int main(int argc, char *argv[])
{
long pagesize;
void *write_buf;
pthread_t fsyncer;
int ret;

if (argc != 2) {
fprintf(stderr, "Use: %s <file path>\n", argv[0]);
return 1;
}

fd = open(argv[1], O_WRONLY | O_CREAT | O_TRUNC | O_DIRECT, 0666);
if (fd == -1) {
perror("Failed to open/create file");
return 1;
}

pagesize = sysconf(_SC_PAGE_SIZE);
if (pagesize == -1) {
perror("Failed to get page size");
return 2;
}

ret = posix_memalign(&write_buf, pagesize, pagesize);
if (ret) {
perror("Failed to allocate buffer");
return 3;
}

ret = pthread_create(&fsyncer, NULL, fsync_loop, NULL);
if (ret != 0) {
fprintf(stderr, "Failed to create writer thread: %d\n", ret);
return 4;
}

while (1) {
ret = do_write(fd, write_buf, pagesize, 0);
if (ret != 0) {
perror("Write failed");
exit(5);
}
}

return 0;
}

$ mkfs.btrfs -f /dev/sdi
$ mount /dev/sdi /mnt/sdi
$ timeout 10 ./repro /mnt/sdi/foo

Usually the race is triggered within less than 1 second. A test case for
fstests will follow soon.

Reported-by: Paulo Dias <paulo.miguel.dias@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219187
Reported-by: Andreas Jahn <jahn-andi@web.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219199
Reported-by: syzbot+4704b3cc972bd76024f1@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/00000000000044ff540620d7dee2@google.com/
Fixes: 939b656bc8ab ("btrfs: fix corruption after buffer fault in during direct IO append write")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge tag 'v6.6.9' into dev-6.6

This is the 6.6.9 stable release

btrfs: free qgroup pertrans reserve on transaction abort

[ Upstream commit b321a52cce062ec7ed385333a33905d22159ce36 ]

If we abort a transaction, we never run the code that frees the pertrans
qgroup

btrfs: free qgroup pertrans reserve on transaction abort

[ Upstream commit b321a52cce062ec7ed385333a33905d22159ce36 ]

If we abort a transaction, we never run the code that frees the pertrans
qgroup reservation. This results in warnings on unmount as that
reservation has been leaked. The leak isn't a huge issue since the fs is
read-only, but it's better to clean it up when we know we can/should. Do
it during the cleanup_transaction step of aborting.

CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

Merge tag 'for-6.6-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

- reject unknown mount options

- adjust transaction abort error messa

Merge tag 'for-6.6-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

- reject unknown mount options

- adjust transaction abort error message level

- fix one more build warning with -Wmaybe-uninitialized

- proper error handling in several COW-related cases

* tag 'for-6.6-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: error out when reallocating block for defrag using a stale transaction
btrfs: error when COWing block from a root that is being deleted
btrfs: error out when COWing block using a stale transaction
btrfs: always print transaction aborted messages with an error level
btrfs: reject unknown mount options early
btrfs: fix some -Wmaybe-uninitialized warnings in ioctl.c

show more ...

btrfs: always print transaction aborted messages with an error level

Commit b7af0635c87f ("btrfs: print transaction aborted messages with an
error level") changed the log level of transaction aborte

btrfs: always print transaction aborted messages with an error level

Commit b7af0635c87f ("btrfs: print transaction aborted messages with an
error level") changed the log level of transaction aborted messages from
a debug level to an error level, so that such messages are always visible
even on production systems where the log level is normally above the debug
level (and also on some syzbot reports).

Later, commit fccf0c842ed4 ("btrfs: move btrfs_abort_transaction to
transaction.c") changed the log level back to debug level when the error
number for a transaction abort should not have a stack trace printed.
This happened for absolutely no reason. It's always useful to print
transaction abort messages with an error level, regardless of whether
the error number should cause a stack trace or not.

So change back the log level to error level.

Fixes: fccf0c842ed4 ("btrfs: move btrfs_abort_transaction to transaction.c")
CC: stable@vger.kernel.org # 6.5+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

show more ...

Merge tag 'kvm-riscv-fixes-6.6-1' of https://github.com/kvm-riscv/linux into HEAD

KVM/riscv fixes for 6.6, take #1

- Fix KVM_GET_REG_LIST API for ISA_EXT registers
- Fix reading ISA_EXT register of

Merge tag 'kvm-riscv-fixes-6.6-1' of https://github.com/kvm-riscv/linux into HEAD

KVM/riscv fixes for 6.6, take #1

- Fix KVM_GET_REG_LIST API for ISA_EXT registers
- Fix reading ISA_EXT register of a missing extension
- Fix ISA_EXT register handling in get-reg-list test
- Fix filtering of AIA registers in get-reg-list test

show more ...

Merge tag 'for-6.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

- several fixes for handling directory item (inserting, removing,
it

Merge tag 'for-6.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

- several fixes for handling directory item (inserting, removing,
iteration, error handling)

- fix transaction commit stalls when auto relocation is running and
blocks other tasks that want to commit

- fix a build error when DEBUG is enabled

- fix lockdep warning in inode number lookup ioctl

- fix race when finishing block group creation

- remove link to obsolete wiki in several files

* tag 'for-6.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
MAINTAINERS: remove links to obsolete btrfs.wiki.kernel.org
btrfs: assert delayed node locked when removing delayed item
btrfs: remove BUG() after failure to insert delayed dir index item
btrfs: improve error message after failure to add delayed dir index item
btrfs: fix a compilation error if DEBUG is defined in btree_dirty_folio
btrfs: check for BTRFS_FS_ERROR in pending ordered assert
btrfs: fix lockdep splat and potential deadlock after failure running delayed items
btrfs: do not block starts waiting on previous transaction commit
btrfs: release path before inode lookup during the ino lookup ioctl
btrfs: fix race between finishing block group creation and its item update

show more ...

btrfs: do not block starts waiting on previous transaction commit

Internally I got a report of very long stalls on normal operations like
creating a new file when auto relocation was running. The r

btrfs: do not block starts waiting on previous transaction commit

Internally I got a report of very long stalls on normal operations like
creating a new file when auto relocation was running. The reporter used
the 'bpf offcputime' tracer to show that we would get stuck in
start_transaction for 5 to 30 seconds, and were always being woken up by
the transaction commit.

Using my timing-everything script, which times how long a function takes
and what percentage of that total time is taken up by its children, I
saw several traces like this

1083 took 32812902424 ns
29929002926 ns 91.2110% wait_for_commit_duration
25568 ns 7.7920e-05% commit_fs_roots_duration
1007751 ns 0.00307% commit_cowonly_roots_duration
446855602 ns 1.36182% btrfs_run_delayed_refs_duration
271980 ns 0.00082% btrfs_run_delayed_items_duration
2008 ns 6.1195e-06% btrfs_apply_pending_changes_duration
9656 ns 2.9427e-05% switch_commit_roots_duration
1598 ns 4.8700e-06% btrfs_commit_device_sizes_duration
4314 ns 1.3147e-05% btrfs_free_log_root_tree_duration

Here I was only tracing functions that happen where we are between
START_COMMIT and UNBLOCKED in order to see what would be keeping us
blocked for so long. The wait_for_commit() we do is where we wait for a
previous transaction that hasn't completed it's commit. This can
include all of the unpin work and other cleanups, which tends to be the
longest part of our transaction commit.

There is no reason we should be blocking new things from entering the
transaction at this point, it just adds to random latency spikes for no
reason.

Fix this by adding a PREP stage. This allows us to properly deal with
multiple committers coming in at the same time, we retain the behavior
that the winner waits on the previous transaction and the losers all
wait for this transaction commit to occur. Nothing else is blocked
during the PREP stage, and then once the wait is complete we switch to
COMMIT_START and all of the same behavior as before is maintained.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

show more ...

Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo V

Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

show more ...

Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/1

Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/121735/

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

show more ...

Merge drm/drm-next into drm-misc-next

Backmerging to get v6.5-rc2.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

ASoC: Merge v6.5-rc2

Get a similar baseline to my other branches, and fixes for people using
the branch.

Merge v6.5-rc1 into drm-misc-fixes

Boris needs 6.5-rc1 in drm-misc-fixes to prevent a conflict.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge branch 'master' into mm-hotfixes-stable

Merge tag 'for-6.5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
"Mainly core changes, refactoring and optimizations.

Performance is imp

Merge tag 'for-6.5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
"Mainly core changes, refactoring and optimizations.

Performance is improved in some areas, overall there may be a
cumulative improvement due to refactoring that removed lookups in the
IO path or simplified IO submission tracking.

Core:

- submit IO synchronously for fast checksums (crc32c and xxhash),
remove high priority worker kthread

- read extent buffer in one go, simplify IO tracking, bio submission
and locking

- remove additional tracking of redirtied extent buffers, originally
added for zoned mode but actually not needed

- track ordered extent pointer in bio to avoid rbtree lookups during
IO

- scrub, use recovered data stripes as cache to avoid unnecessary
read

- in zoned mode, optimize logical to physical mappings of extents

- remove PageError handling, not set by VFS nor writeback

- cleanups, refactoring, better structure packing

- lots of error handling improvements

- more assertions, lockdep annotations

- print assertion failure with the exact line where it happens

- tracepoint updates

- more debugging prints

Performance:

- speedup in fsync(), better tracking of inode logged status can
avoid transaction commit

- IO path structures track logical offsets in data structures and
does not need to look it up

User visible changes:

- don't commit transaction for every created subvolume, this can
reduce time when many subvolumes are created in a batch

- print affected files when relocation fails

- trigger orphan file cleanup during START_SYNC ioctl

Notable fixes:

- fix crash when disabling quota and relocation

- fix crashes when removing roots from drity list

- fix transacion abort during relocation when converting from newer
profiles not covered by fallback

- in zoned mode, stop reclaiming block groups if filesystem becomes
read-only

- fix rare race condition in tree mod log rewind that can miss some
btree node slots

- with enabled fsverity, drop up-to-date page bit in case the
verification fails"

* tag 'for-6.5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (194 commits)
btrfs: fix race between quota disable and relocation
btrfs: add comment to struct btrfs_fs_info::dirty_cowonly_roots
btrfs: fix race when deleting free space root from the dirty cow roots list
btrfs: fix race when deleting quota root from the dirty cow roots list
btrfs: tracepoints: also show actual number of the outstanding extents
btrfs: update i_version in update_dev_time
btrfs: make btrfs_compressed_bioset static
btrfs: add handling for RAID1C23/DUP to btrfs_reduce_alloc_profile
btrfs: scrub: remove btrfs_fs_info::scrub_wr_completion_workers
btrfs: scrub: remove scrub_ctx::csum_list member
btrfs: do not BUG_ON after failure to migrate space during truncation
btrfs: do not BUG_ON on failure to get dir index for new snapshot
btrfs: send: do not BUG_ON() on unexpected symlink data extent
btrfs: do not BUG_ON() when dropping inode items from log root
btrfs: replace BUG_ON() at split_item() with proper error handling
btrfs: do not BUG_ON() on tree mod log failures at btrfs_del_ptr()
btrfs: do not BUG_ON() on tree mod log failures at insert_ptr()
btrfs: do not BUG_ON() on tree mod log failure at insert_new_root()
btrfs: do not BUG_ON() on tree mod log failures at push_nodes_for_insert()
btrfs: abort transaction at update_ref_for_cow() when ref count is zero
...

show more ...

btrfs: don't hold an extra reference for redirtied buffers

When btrfs_redirty_list_add redirties a buffer, it also acquires
an extra reference that is released on transaction commit. But
this is no

btrfs: don't hold an extra reference for redirtied buffers

When btrfs_redirty_list_add redirties a buffer, it also acquires
an extra reference that is released on transaction commit. But
this is not required as buffers that are dirty or under writeback
are never freed (look for calls to extent_buffer_under_io())).

Remove the extra reference and the infrastructure used to drop it
again.

History behind redirty logic:

In the first place, it used releasing_list to hold all the
to-be-released extent buffers, and decided which buffers to re-dirty at
the commit time. Then, in a later version, the behaviour got changed to
re-dirty a necessary buffer and add re-dirtied one to the list in
btrfs_free_tree_block(). In short, the list was there mostly for the
patch series' historical reason.

Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[ add Naohiro's comment regarding history ]
Signed-off-by: David Sterba <dsterba@suse.com>

show more ...

Merge branch 'next' into for-linus

Prepare input updates for 6.4 merge window.

Merge drm/drm-next into drm-intel-gt-next

Need to pull in commit from drm-next (earlier in drm-intel-next):

1eca0778f4b3 ("drm/i915: add struct i915_dsm to wrap dsm members together")

In order to

Merge drm/drm-next into drm-intel-gt-next

Need to pull in commit from drm-next (earlier in drm-intel-next):

1eca0778f4b3 ("drm/i915: add struct i915_dsm to wrap dsm members together")

In order to merge following patch to drm-intel-gt-next:

https://patchwork.freedesktop.org/patch/530942/?series=114925&rev=6

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

show more ...

Merge drm/drm-next into drm-intel-next

Catch up with 6.3-rc cycle...

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge remote-tracking branch 'drm/drm-next' into msm-next

Merge drm-next into msm-next to pick up external clk and PM dependencies
for improved a6xx GPU reset sequence.

Signed-off-by: Rob Clark <ro

Merge remote-tracking branch 'drm/drm-next' into msm-next

Merge drm-next into msm-next to pick up external clk and PM dependencies
for improved a6xx GPU reset sequence.

Signed-off-by: Rob Clark <robdclark@chromium.org>

show more ...

Merge tag 'v6.3-rc2' into next

Merge with mainline to get of_property_present() and other newer APIs.

Merge drm/drm-fixes into drm-misc-fixes

Backmerging to get latest upstream.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-next into drm-misc-next

Backmerging to get v6.3-rc1 and sync with the other DRM trees.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge remote-tracking branch 'acme/perf-tools' into perf-tools-next

To pick up perf-tools fixes just merged upstream.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>