commit 0b0747d507 upstream.
The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.
PID: 17360 TASK: ffff95c1090c5c40 CPU: 41 COMMAND: "mrdiagd"
!# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
!# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
!# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
# 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
# 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
# 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
# 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
# 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
# 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
# 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
#10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
#11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
#12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
#13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
#14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
#15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
#16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
#17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
#18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
#19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
#20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
#21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
#22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
#23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
#24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
#25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
#26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
#27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0
PID: 17355 TASK: ffff95c1090c3d80 CPU: 29 COMMAND: "mrdiagd"
!# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
!# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
# 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
# 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
# 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
# 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
# 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
# 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
# 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
# 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
#10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
#11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
#12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
#13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
#14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
#15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
#16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
#17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0
The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 24e0e61db3 upstream.
In AHCI 1.3.1, the register description for CAP.SSC:
"When cleared to ‘0’, software must not allow the HBA to initiate
transitions to the Slumber state via agressive link power management nor
the PxCMD.ICC field in each port, and the PxSCTL.IPM field in each port
must be programmed to disallow device initiated Slumber requests."
In AHCI 1.3.1, the register description for CAP.PSC:
"When cleared to ‘0’, software must not allow the HBA to initiate
transitions to the Partial state via agressive link power management nor
the PxCMD.ICC field in each port, and the PxSCTL.IPM field in each port
must be programmed to disallow device initiated Partial requests."
Ensure that we always set the corresponding bits in PxSCTL.IPM, such that
a device is not allowed to initiate transitions to power states which are
unsupported by the HBA.
DevSleep is always initiated by the HBA, however, for completeness, set the
corresponding bit in PxSCTL.IPM such that agressive link power management
cannot transition to DevSleep if DevSleep is not supported.
sata_link_scr_lpm() is used by libahci, ata_piix and libata-pmp.
However, only libahci has the ability to read the CAP/CAP2 register to see
if these features are supported. Therefore, in order to not introduce any
regressions on ata_piix or libata-pmp, create flags that indicate that the
respective feature is NOT supported. This way, the behavior for ata_piix
and libata-pmp should remain unchanged.
This change is based on a patch originally submitted by Runa Guo-oc.
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Fixes: 1152b2617a ("libata: implement sata_link_scr_lpm() and make ata_dev_set_feature() global")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ee34a82e89 upstream.
During the ino lookup ioctl we can end up calling btrfs_iget() to get an
inode reference while we are holding on a root's btree. If btrfs_iget()
needs to lookup the inode from the root's btree, because it's not
currently loaded in memory, then it will need to lock another or the
same path in the same root btree. This may result in a deadlock and
trigger the following lockdep splat:
WARNING: possible circular locking dependency detected
6.5.0-rc7-syzkaller-00004-gf7757129e3de #0 Not tainted
------------------------------------------------------
syz-executor277/5012 is trying to acquire lock:
ffff88802df41710 (btrfs-tree-01){++++}-{3:3}, at: __btrfs_tree_read_lock+0x2f/0x220 fs/btrfs/locking.c:136
but task is already holding lock:
ffff88802df418e8 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x2f/0x220 fs/btrfs/locking.c:136
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (btrfs-tree-00){++++}-{3:3}:
down_read_nested+0x49/0x2f0 kernel/locking/rwsem.c:1645
__btrfs_tree_read_lock+0x2f/0x220 fs/btrfs/locking.c:136
btrfs_search_slot+0x13a4/0x2f80 fs/btrfs/ctree.c:2302
btrfs_init_root_free_objectid+0x148/0x320 fs/btrfs/disk-io.c:4955
btrfs_init_fs_root fs/btrfs/disk-io.c:1128 [inline]
btrfs_get_root_ref+0x5ae/0xae0 fs/btrfs/disk-io.c:1338
btrfs_get_fs_root fs/btrfs/disk-io.c:1390 [inline]
open_ctree+0x29c8/0x3030 fs/btrfs/disk-io.c:3494
btrfs_fill_super+0x1c7/0x2f0 fs/btrfs/super.c:1154
btrfs_mount_root+0x7e0/0x910 fs/btrfs/super.c:1519
legacy_get_tree+0xef/0x190 fs/fs_context.c:611
vfs_get_tree+0x8c/0x270 fs/super.c:1519
fc_mount fs/namespace.c:1112 [inline]
vfs_kern_mount+0xbc/0x150 fs/namespace.c:1142
btrfs_mount+0x39f/0xb50 fs/btrfs/super.c:1579
legacy_get_tree+0xef/0x190 fs/fs_context.c:611
vfs_get_tree+0x8c/0x270 fs/super.c:1519
do_new_mount+0x28f/0xae0 fs/namespace.c:3335
do_mount fs/namespace.c:3675 [inline]
__do_sys_mount fs/namespace.c:3884 [inline]
__se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
-> #0 (btrfs-tree-01){++++}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3142 [inline]
check_prevs_add kernel/locking/lockdep.c:3261 [inline]
validate_chain kernel/locking/lockdep.c:3876 [inline]
__lock_acquire+0x39ff/0x7f70 kernel/locking/lockdep.c:5144
lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5761
down_read_nested+0x49/0x2f0 kernel/locking/rwsem.c:1645
__btrfs_tree_read_lock+0x2f/0x220 fs/btrfs/locking.c:136
btrfs_tree_read_lock fs/btrfs/locking.c:142 [inline]
btrfs_read_lock_root_node+0x292/0x3c0 fs/btrfs/locking.c:281
btrfs_search_slot_get_root fs/btrfs/ctree.c:1832 [inline]
btrfs_search_slot+0x4ff/0x2f80 fs/btrfs/ctree.c:2154
btrfs_lookup_inode+0xdc/0x480 fs/btrfs/inode-item.c:412
btrfs_read_locked_inode fs/btrfs/inode.c:3892 [inline]
btrfs_iget_path+0x2d9/0x1520 fs/btrfs/inode.c:5716
btrfs_search_path_in_tree_user fs/btrfs/ioctl.c:1961 [inline]
btrfs_ioctl_ino_lookup_user+0x77a/0xf50 fs/btrfs/ioctl.c:2105
btrfs_ioctl+0xb0b/0xd40 fs/btrfs/ioctl.c:4683
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xf8/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
rlock(btrfs-tree-00);
lock(btrfs-tree-01);
lock(btrfs-tree-00);
rlock(btrfs-tree-01);
*** DEADLOCK ***
1 lock held by syz-executor277/5012:
#0: ffff88802df418e8 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x2f/0x220 fs/btrfs/locking.c:136
stack backtrace:
CPU: 1 PID: 5012 Comm: syz-executor277 Not tainted 6.5.0-rc7-syzkaller-00004-gf7757129e3de #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
check_noncircular+0x375/0x4a0 kernel/locking/lockdep.c:2195
check_prev_add kernel/locking/lockdep.c:3142 [inline]
check_prevs_add kernel/locking/lockdep.c:3261 [inline]
validate_chain kernel/locking/lockdep.c:3876 [inline]
__lock_acquire+0x39ff/0x7f70 kernel/locking/lockdep.c:5144
lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5761
down_read_nested+0x49/0x2f0 kernel/locking/rwsem.c:1645
__btrfs_tree_read_lock+0x2f/0x220 fs/btrfs/locking.c:136
btrfs_tree_read_lock fs/btrfs/locking.c:142 [inline]
btrfs_read_lock_root_node+0x292/0x3c0 fs/btrfs/locking.c:281
btrfs_search_slot_get_root fs/btrfs/ctree.c:1832 [inline]
btrfs_search_slot+0x4ff/0x2f80 fs/btrfs/ctree.c:2154
btrfs_lookup_inode+0xdc/0x480 fs/btrfs/inode-item.c:412
btrfs_read_locked_inode fs/btrfs/inode.c:3892 [inline]
btrfs_iget_path+0x2d9/0x1520 fs/btrfs/inode.c:5716
btrfs_search_path_in_tree_user fs/btrfs/ioctl.c:1961 [inline]
btrfs_ioctl_ino_lookup_user+0x77a/0xf50 fs/btrfs/ioctl.c:2105
btrfs_ioctl+0xb0b/0xd40 fs/btrfs/ioctl.c:4683
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xf8/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f0bec94ea39
Fix this simply by releasing the path before calling btrfs_iget() as at
point we don't need the path anymore.
Reported-by: syzbot+bf66ad948981797d2f1d@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/00000000000045fa140603c4a969@google.com/
Fixes: 23d0b79dfa ("btrfs: Add unprivileged version of ino_lookup ioctl")
CC: stable@vger.kernel.org # 4.19+
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>
commit 724768a393 upstream.
ovl_{read,write}_iter() always call fdput(real) to put one or zero
refcounts of the real file, but for aio, whether it was submitted or not,
ovl_aio_put() also calls fdput(), which is not balanced. This is only a
problem in the less common case when FDPUT_FPUT flag is set.
To fix the problem use get_file() to take file refcount and use fput()
instead of fdput() in ovl_aio_put().
Fixes: 2406a307ac ("ovl: implement async IO routines")
Cc: <stable@vger.kernel.org> # v5.6
Reviewed-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ab04830202 upstream.
Some local filesystems support setting persistent fileattr flags
(e.g. FS_NOATIME_FL) on directories and regular files via ioctl.
Some of those persistent fileattr flags are reflected to vfs as
in-memory inode flags (e.g. S_NOATIME).
Overlayfs uses the in-memory inode flags (e.g. S_NOATIME) on a lower file
as an indication that a the lower file may have persistent inode fileattr
flags (e.g. FS_NOATIME_FL) that need to be copied to upper file.
However, in some cases, the S_NOATIME in-memory flag could be a false
indication for persistent FS_NOATIME_FL fileattr. For example, with NFS
and FUSE lower fs, as was the case in the two bug reports, the S_NOATIME
flag is set unconditionally for all inodes.
Users cannot set persistent fileattr flags on symlinks and special files,
but in some local fs, such as ext4/btrfs/tmpfs, the FS_NOATIME_FL fileattr
flag are inheritted to symlinks and special files from parent directory.
In both cases described above, when lower symlink has the S_NOATIME flag,
overlayfs will try to copy the symlink's fileattrs and fail with error
ENOXIO, because it could not open the symlink for the ioctl security hook.
To solve this failure, do not attempt to copyup fileattrs for anything
other than directories and regular files.
Reported-by: Ruiwen Zhao <ruiwen@google.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217850
Fixes: 72db82115d ("ovl: copy up sync/noatime fileattr flags")
Cc: <stable@vger.kernel.org> # v5.15
Reviewed-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5d1f903f75 upstream.
Changing the mode of symlinks is meaningless as the vfs doesn't take the
mode of a symlink into account during path lookup permission checking.
However, the vfs doesn't block mode changes on symlinks. This however,
has lead to an untenable mess roughly classifiable into the following
two categories:
(1) Filesystems that don't implement a i_op->setattr() for symlinks.
Such filesystems may or may not know that without i_op->setattr()
defined, notify_change() falls back to simple_setattr() causing the
inode's mode in the inode cache to be changed.
That's a generic issue as this will affect all non-size changing
inode attributes including ownership changes.
Example: afs
(2) Filesystems that fail with EOPNOTSUPP but change the mode of the
symlink nonetheless.
Some filesystems will happily update the mode of a symlink but still
return EOPNOTSUPP. This is the biggest source of confusion for
userspace.
The EOPNOTSUPP in this case comes from POSIX ACLs. Specifically it
comes from filesystems that call posix_acl_chmod(), e.g., btrfs via
if (!err && attr->ia_valid & ATTR_MODE)
err = posix_acl_chmod(idmap, dentry, inode->i_mode);
Filesystems including btrfs don't implement i_op->set_acl() so
posix_acl_chmod() will report EOPNOTSUPP.
When posix_acl_chmod() is called, most filesystems will have
finished updating the inode.
Perversely, this has the consequences that this behavior may depend
on two kconfig options and mount options:
* CONFIG_POSIX_ACL={y,n}
* CONFIG_${FSTYPE}_POSIX_ACL={y,n}
* Opt_acl, Opt_noacl
Example: btrfs, ext4, xfs
The only way to change the mode on a symlink currently involves abusing
an O_PATH file descriptor in the following manner:
fd = openat(-1, "/path/to/link", O_CLOEXEC | O_PATH | O_NOFOLLOW);
char path[PATH_MAX];
snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
chmod(path, 0000);
But for most major filesystems with POSIX ACL support such as btrfs,
ext4, ceph, tmpfs, xfs and others this will fail with EOPNOTSUPP with
the mode still updated due to the aforementioned posix_acl_chmod()
nonsense.
So, given that for all major filesystems this would fail with EOPNOTSUPP
and that both glibc (cf. [1]) and musl (cf. [2]) outright block mode
changes on symlinks we should just try and block mode changes on
symlinks directly in the vfs and have a clean break with this nonsense.
If this causes any regressions, we do the next best thing and fix up all
filesystems that do return EOPNOTSUPP with the mode updated to not call
posix_acl_chmod() on symlinks.
But as usual, let's try the clean cut solution first. It's a simple
patch that can be easily reverted. Not marking this for backport as I'll
do that manually if we're reasonably sure that this works and there are
no strong objections.
We could block this in chmod_common() but it's more appropriate to do it
notify_change() as it will also mean that we catch filesystems that
change symlink permissions explicitly or accidently.
Similar proposals were floated in the past as in [3] and [4] and again
recently in [5]. There's also a couple of bugs about this inconsistency
as in [6] and [7].
Link: https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/fchmodat.c;h=99527a3727e44cb8661ee1f743068f108ec93979;hb=HEAD [1]
Link: https://git.musl-libc.org/cgit/musl/tree/src/stat/fchmodat.c [2]
Link: https://lore.kernel.org/all/20200911065733.GA31579@infradead.org [3]
Link: https://sourceware.org/legacy-ml/libc-alpha/2020-02/msg00518.html [4]
Link: https://lore.kernel.org/lkml/87lefmbppo.fsf@oldenburg.str.redhat.com [5]
Link: https://sourceware.org/legacy-ml/libc-alpha/2020-02/msg00467.html [6]
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=14578#c17 [7]
Reviewed-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org # please backport to all LTSes but not before v6.6-rc2 is tagged
Suggested-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Florian Weimer <fweimer@redhat.com>
Message-Id: <20230712-vfs-chmod-symlinks-v2-1-08cfb92b61dd@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit df203da47f ]
There is a compile error when this commit is added:
md: raid1: fix potential OOB in raid1_remove_disk()
drivers/md/raid1.c: In function 'raid1_remove_disk':
drivers/md/raid1.c:1844:9: error: ISO C90 forbids mixed declarations
and code [-Werror=declaration-after-statement]
1844 | struct raid1_info *p = conf->mirrors + number;
| ^~~~~~
That's because the new code was inserted before the struct.
The change is move the struct command above this commit.
Fixes: 8b0472b50b ("md: raid1: fix potential OOB in raid1_remove_disk()")
Signed-off-by: Nigel Croxon <ncroxon@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/46d929d0-2aab-4cf2-b2bf-338963e8ba5a@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b9080468ca ]
__symbol_put() is really meant as an internal helper and is not available
when module unloading is disabled, unlike the previously used symbol_put():
samples/hw_breakpoint/data_breakpoint.c: In function 'hw_break_module_exit':
samples/hw_breakpoint/data_breakpoint.c:73:9: error: implicit declaration of function '__symbol_put'; did you mean '__symbol_get'? [-Werror=implicit-function-declaration]
The hw_break_module_exit() function is not actually used when module
unloading is disabled, but it still causes the build failure for an
undefined identifier. Enclose this one call in an appropriate #ifdef to
clarify what the requirement is. Leaving out the entire exit function
would also work but feels less clar in this case.
Fixes: 910e230d5f ("samples/hw_breakpoint: Fix kernel BUG 'invalid opcode: 0000'")
Fixes: d8a84d33a4 ("samples/hw_breakpoint: drop use of kallsyms_lookup_name()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 75b2f7e4c9 ]
-flto* implies -ffunction-sections. With LTO enabled, ld.lld generates
multiple .text sections for purgatory.ro:
$ readelf -S purgatory.ro | grep " .text"
[ 1] .text PROGBITS 0000000000000000 00000040
[ 7] .text.purgatory PROGBITS 0000000000000000 000020e0
[ 9] .text.warn PROGBITS 0000000000000000 000021c0
[13] .text.sha256_upda PROGBITS 0000000000000000 000022f0
[15] .text.sha224_upda PROGBITS 0000000000000000 00002be0
[17] .text.sha256_fina PROGBITS 0000000000000000 00002bf0
[19] .text.sha224_fina PROGBITS 0000000000000000 00002cc0
This causes WARNING from kexec_purgatory_setup_sechdrs():
WARNING: CPU: 26 PID: 110894 at kernel/kexec_file.c:919
kexec_load_purgatory+0x37f/0x390
Fix this by disabling LTO for purgatory.
[ AFAICT, x86 is the only arch that supports LTO and purgatory. ]
We could also fix this with an explicit linker script to rejoin .text.*
sections back into .text. However, given the benefit of LTOing purgatory
is small, simply disable the production of more .text.* sections for now.
Fixes: b33fff07e3 ("x86, build: allow LTO to be selected")
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/r/20230914170138.995606-1-song@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f530ee95b7 ]
The decompressor has a hard limit on the number of page tables it can
allocate. This limit is defined at compile-time and will cause boot
failure if it is reached.
The kernel is very strict and calculates the limit precisely for the
worst-case scenario based on the current configuration. However, it is
easy to forget to adjust the limit when a new use-case arises. The
worst-case scenario is rarely encountered during sanity checks.
In the case of enabling 5-level paging, a use-case was overlooked. The
limit needs to be increased by one to accommodate the additional level.
This oversight went unnoticed until Aaron attempted to run the kernel
via kexec with 5-level paging and unaccepted memory enabled.
Update wost-case calculations to include 5-level paging.
To address this issue, let's allocate some extra space for page tables.
128K should be sufficient for any use-case. The logic can be simplified
by using a single value for all kernel configurations.
[ Also add a warning, should this memory run low - by Dave Hansen. ]
Fixes: 34bbb0009f ("x86/boot/compressed: Enable 5-level paging during decompression stage")
Reported-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230915070221.10266-1-kirill.shutemov@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7dcc683db3 ]
Since debugfs_create_file() returns ERR_PTR and never NULL, use IS_ERR() to
check the return value.
Fixes: 2fcbc569b9 ("scsi: lpfc: Make debugfs ktime stats generic for NVME and SCSI")
Fixes: 4c47efc140 ("scsi: lpfc: Move SCSI and NVME Stats to hardware queue structures")
Fixes: 6a828b0f61 ("scsi: lpfc: Support non-uniform allocation of MSIX vectors to hardware queues")
Fixes: 95bfc6d8ad ("scsi: lpfc: Make FW logging dynamically configurable")
Fixes: 9f77870870 ("scsi: lpfc: Add debugfs support for cm framework buffers")
Fixes: c490850a09 ("scsi: lpfc: Adapt partitioned XRI lists to efficient sharing")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Link: https://lore.kernel.org/r/20230906030809.2847970-1-ruanjinjie@huawei.com
Reviewed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7583028d35 ]
The timeout arg of usb_bulk_msg() is ms already, which has been converted
to jiffies by msecs_to_jiffies() in usb_start_wait_urb(). So fix the usage
by removing the redundant msecs_to_jiffies() in the macros.
And as Hans suggested, also remove msecs_to_jiffies() for the IDLE_TIMEOUT
macro to make it consistent here and so change IDLE_TIMEOUT to
msecs_to_jiffies(IDLE_TIMEOUT) where it is used.
Fixes: e4f86e4371 ("drm: Add Grain Media GM12U320 driver v2")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230904021421.1663892-1-ruanjinjie@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6bfe3959b0 ]
The function btrfs_validate_super() should verify the metadata_uuid in
the provided superblock argument. Because, all its callers expect it to
do that.
Such as in the following stacks:
write_all_supers()
sb = fs_info->super_for_commit;
btrfs_validate_write_super(.., sb)
btrfs_validate_super(.., sb, ..)
scrub_one_super()
btrfs_validate_super(.., sb, ..)
And
check_dev_super()
btrfs_validate_super(.., sb, ..)
However, it currently verifies the fs_info::super_copy::metadata_uuid
instead. Fix this using the correct metadata_uuid in the superblock
argument.
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4844c3664a ]
In some cases, we need to read the FSID from the superblock when the
metadata_uuid is not set, and otherwise, read the metadata_uuid. So,
add a helper.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 6bfe3959b0 ("btrfs: compare the correct fsid/metadata_uuid in btrfs_validate_super")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d42f0c6ad5 ]
The latest version of grep claims the egrep is now obsolete so the build
now contains warnings that look like:
egrep: warning: egrep is obsolescent; using grep -E
fix this up by moving the related file to use "grep -E" instead.
Here are the steps to install the latest grep:
wget http://ftp.gnu.org/gnu/grep/grep-3.8.tar.gz
tar xf grep-3.8.tar.gz
cd grep-3.8 && ./configure && make
sudo make install
export PATH=/usr/local/bin:$PATH
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Stable-dep-of: 4fe4a6374c ("MIPS: Only fiddle with CHECKFLAGS if `need-compiler'")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 25f97138f8 ]
Allow a brcmnand_soc instance to provide a custom set of I/O operations
which we will require when using this driver on a BCMA bus which is not
directly memory mapped I/O. Update the nand_{read,write}_reg accordingly
to use the SoC operations if provided.
To minimize the penalty on other SoCs which do support standard MMIO
accesses, we use a static key which is disabled by default and gets
enabled if a soc implementation does provide I/O operations.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220107184614.2670254-3-f.fainelli@gmail.com
Stable-dep-of: 2ec2839a90 ("mtd: rawnand: brcmnand: Fix ECC level field setting for v7.2 controller")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2dfba3bb40 ]
We got a filesystem inconsistency issue below while running generic/475
I/O failure pressure test with fast_commit feature enabled.
Symlink /p3/d3/d1c/d6c/dd6/dce/l101 (inode #132605) is invalid.
If fast_commit feature is enabled, a special fast_commit journal area is
appended to the end of the normal journal area. The journal->j_last
point to the first unused block behind the normal journal area instead
of the whole log area, and the journal->j_fc_last point to the first
unused block behind the fast_commit journal area. While doing journal
recovery, do_one_pass(PASS_SCAN) should first scan the normal journal
area and turn around to the first block once it meet journal->j_last,
but the wrap() macro misuse the journal->j_fc_last, so the recovering
could not read the next magic block (commit block perhaps) and would end
early mistakenly and missing tN and every transaction after it in the
following example. Finally, it could lead to filesystem inconsistency.
| normal journal area | fast commit area |
+-------------------------------------------------+------------------+
| tN(rere) | tN+1 |~| tN-x |...| tN-1 | tN(front) | .... |
+-------------------------------------------------+------------------+
/ / /
start journal->j_last journal->j_fc_last
This patch fix it by use the correct ending journal->j_last.
Fixes: 5b849b5f96 ("jbd2: fast commit recovery path")
Cc: stable@kernel.org
Reported-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/linux-ext4/20230613043120.GB1584772@mit.edu/
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230626073322.3956567-1-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f7f497cb70 ]
This patch kills t_handle_lock transaction spinlock completely from
jbd2.
To explain the reasoning, currently there were three sites at which
this spinlock was used.
1. jbd2_journal_wait_updates()
a. Based on careful code review it can be seen that, we don't need this
lock here. This is since we wait for any currently ongoing updates
based on a atomic variable t_updates. And we anyway don't take any
t_handle_lock while in stop_this_handle().
i.e.
write_lock(&journal->j_state_lock()
jbd2_journal_wait_updates() stop_this_handle()
while (atomic_read(txn->t_updates) { |
DEFINE_WAIT(wait); |
prepare_to_wait(); |
if (atomic_read(txn->t_updates) if (atomic_dec_and_test(txn->t_updates))
write_unlock(&journal->j_state_lock);
schedule(); wake_up()
write_lock(&journal->j_state_lock);
finish_wait();
}
txn->t_state = T_COMMIT
write_unlock(&journal->j_state_lock);
b. Also note that between atomic_inc(&txn->t_updates) in
start_this_handle() and jbd2_journal_wait_updates(), the
synchronization happens via read_lock(journal->j_state_lock) in
start_this_handle();
2. jbd2_journal_extend()
a. jbd2_journal_extend() is called with the handle of each process from
task_struct. So no lock required in updating member fields of handle_t
b. For member fields of h_transaction, all updates happens only via
atomic APIs (which is also within read_lock()).
So, no need of this transaction spinlock.
3. update_t_max_wait()
Based on Jan suggestion, this can be carefully removed using atomic
cmpxchg API.
Note that there can be several processes which are waiting for a new
transaction to be allocated and started. For doing this only one
process will succeed in taking write_lock() and allocating a new txn.
After that all of the process will be updating the t_max_wait (max
transaction wait time). This can be done via below method w/o taking
any locks using atomic cmpxchg.
For more details refer [1]
new = get_new_val();
old = READ_ONCE(ptr->max_val);
while (old < new)
old = cmpxchg(&ptr->max_val, old, new);
[1]: https://lwn.net/Articles/849237/
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/d89e599658b4a1f3893a48c6feded200073037fc.1644992076.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: 2dfba3bb40 ("jbd2: correct the end of the journal recovery scan range")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 696ffaf50e ]
Printing to consoles can be deferred for several reasons:
- explicitly with printk_deferred()
- printk() in NMI context
- recursive printk() calls
The current implementation is not consistent. For printk_deferred(),
irq work is scheduled twice. For NMI und recursive, panic CPU
suppression and caller delays are not properly enforced.
Correct these inconsistencies by consolidating the deferred printing
code so that vprintk_deferred() is the top-level function for
deferred printing and vprintk_emit() will perform whichever irq_work
queueing is appropriate.
Also add kerneldoc for wake_up_klogd() and defer_console_output() to
clarify their differences and appropriate usage.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230717194607.145135-6-john.ogness@linutronix.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4d0fe8c52b ]
When I register a kset in the following way:
static struct kset my_kset;
kobject_set_name(&my_kset.kobj, "my_kset");
ret = kset_register(&my_kset);
A null pointer dereference exception is occurred:
[ 4453.568337] Unable to handle kernel NULL pointer dereference at \
virtual address 0000000000000028
... ...
[ 4453.810361] Call trace:
[ 4453.813062] kobject_get_ownership+0xc/0x34
[ 4453.817493] kobject_add_internal+0x98/0x274
[ 4453.822005] kset_register+0x5c/0xb4
[ 4453.825820] my_kobj_init+0x44/0x1000 [my_kset]
... ...
Because I didn't initialize my_kset.kobj.ktype.
According to the description in Documentation/core-api/kobject.rst:
- A ktype is the type of object that embeds a kobject. Every structure
that embeds a kobject needs a corresponding ktype.
So add sanity check to make sure kset->kobj.ktype is not NULL.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20230805084114.1298-2-thunder.leizhen@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dda4b60ed7 ]
Some NXP processor using chipidea IP has a bug when frame babble is
detected.
As per 4.15.1.1.1 Serial Bus Babble:
A babble condition also exists if IN transaction is in progress at
High-speed SOF2 point. This is called frame babble. The host controller
must disable the port to which the frame babble is detected.
The USB controller has disabled the port (PE cleared) and has asserted
USBERRINT when frame babble is detected, but PEC is not asserted.
Therefore, the SW isn't aware that port has been disabled. Then the
SW keeps sending packets to this port, but all of the transfers will
fail.
This workaround will firstly assert PCD by SW when USBERRINT is detected
and then judge whether port change has really occurred or not by polling
roothub status. Because the PEC doesn't get asserted in our case, this
patch will also assert it by SW when specific conditions are satisfied.
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20230809024432.535160-1-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 801f287c93 ]
The function lio_target_nacl_info_show() uses sprintf() in a loop to print
details for every iSCSI connection in a session without checking for the
buffer length. With enough iSCSI connections it's possible to overflow the
buffer provided by configfs and corrupt the memory.
This patch replaces sprintf() with sysfs_emit_at() that checks for buffer
boundries.
Signed-off-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
Link: https://lore.kernel.org/r/20230722152657.168859-2-k.shelekhin@yadro.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 49d736313d ]
In function size_from_channelarray(), the return value 'bytes' is defined
as int type. However, the calcution of 'bytes' in this function is designed
to use the unsigned int type. So it is necessary to change 'bytes' type to
unsigned int to avoid integer overflow.
The size_from_channelarray() is called in main() function, its return value
is directly multipled by 'buf_len' and then used as the malloc() parameter.
The 'buf_len' is completely controllable by user, thus a multiplication
overflow may occur here. This could allocate an unexpected small area.
Signed-off-by: Chenyuan Mi <michenyuan@huawei.com>
Link: https://lore.kernel.org/r/20230725092407.62545-1-michenyuan@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2319b9c87f ]
The device may be scheduled during the resume process,
so this cannot appear in atomic operations. Since
pm_runtime_set_active will resume suppliers, put set
active outside the spin lock, which is only used to
protect the struct cdns data structure, otherwise the
kernel will report the following warning:
BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1163
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 651, name: sh
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
CPU: 0 PID: 651 Comm: sh Tainted: G WC 6.1.20 #1
Hardware name: Freescale i.MX8QM MEK (DT)
Call trace:
dump_backtrace.part.0+0xe0/0xf0
show_stack+0x18/0x30
dump_stack_lvl+0x64/0x80
dump_stack+0x1c/0x38
__might_resched+0x1fc/0x240
__might_sleep+0x68/0xc0
__pm_runtime_resume+0x9c/0xe0
rpm_get_suppliers+0x68/0x1b0
__pm_runtime_set_status+0x298/0x560
cdns_resume+0xb0/0x1c0
cdns3_controller_resume.isra.0+0x1e0/0x250
cdns3_plat_resume+0x28/0x40
Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20230616021952.1025854-1-xiaolei.wang@windriver.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2e1796fd49 ]
It was completely unnecessary to use BUG in buffer_prepare().
Just replace it with an error return. This also fixes a smatch warning:
drivers/media/pci/cx23885/cx23885-video.c:422 buffer_prepare() error: uninitialized symbol 'ret'.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ee630b29ea ]
BUG_ON is unnecessary here, and in addition it confuses smatch.
Replacing this with an error return help resolve this smatch
warning:
drivers/media/tuners/qt1010.c:350 qt1010_init() error: buffer overflow 'i2c_data' 34 <= 34
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b97719a669 ]
In gl861_i2c_master_xfer, msg is controlled by user. When msg[i].buf
is null and msg[i].len is zero, former checks on msg[i].buf would be
passed. Malicious data finally reach gl861_i2c_master_xfer. If accessing
msg[i].buf[0] without sanity check, null ptr deref would happen.
We add check on msg[i].len to prevent crash.
Similar commit:
commit 0ed554fd76
("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1047f93430 ]
In az6007_i2c_xfer, msg is controlled by user. When msg[i].buf
is null and msg[i].len is zero, former checks on msg[i].buf would be
passed. Malicious data finally reach az6007_i2c_xfer. If accessing
msg[i].buf[0] without sanity check, null ptr deref would happen.
We add check on msg[i].len to prevent crash.
Similar commit:
commit 0ed554fd76
("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c30411266f ]
In anysee_master_xfer, msg is controlled by user. When msg[i].buf
is null and msg[i].len is zero, former checks on msg[i].buf would be
passed. Malicious data finally reach anysee_master_xfer. If accessing
msg[i].buf[0] without sanity check, null ptr deref would happen.
We add check on msg[i].len to prevent crash.
Similar commit:
commit 0ed554fd76
("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil: add spaces around +]
Signed-off-by: Sasha Levin <sashal@kernel.org>