Linux kernel
============
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several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
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Pull btrfs fix from David Sterba:
"One more patch that we'd like to get to 5.12 before release.
It's changing where and how the superblock is stored in the zoned
mode. It is an on-disk format change but so far there are no
implications for users as the proper mkfs support hasn't been merged
and is waiting for the kernel side to settle.
Until now, the superblocks were derived from the zone index, but zone
size can differ per device. This is changed to be based on fixed
offset values, to make it independent of the device zone size.
The work on that got a bit delayed, we discussed the exact locations
to support potential device sizes and usecases. (Partially delayed
also due to my vacation.) Having that in the same release where the
zoned mode is declared usable is highly desired, there are userspace
projects that need to be updated to recognize the feature. Pushing
that to the next release would make things harder to test"
* tag 'for-5.12-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: zoned: move superblock logging zone location
Pull locking fixlets from Ingo Molnar:
"Two minor fixes: one for a Clang warning, the other improves an
ambiguous/confusing kernel log message"
* tag 'locking-urgent-2021-04-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
lockdep: Address clang -Wformat warning printing for %hd
lockdep: Add a missing initialization hint to the "INFO: Trying to register non-static key" message
Moves the location of the superblock logging zones. The new locations of
the logging zones are now determined based on fixed block addresses
instead of on fixed zone numbers.
The old placement method based on fixed zone numbers causes problems when
one needs to inspect a file system image without access to the drive zone
information. In such case, the super block locations cannot be reliably
determined as the zone size is unknown. By locating the superblock logging
zones using fixed addresses, we can scan a dumped file system image without
the zone information since a super block copy will always be present at or
after the fixed known locations.
Introduce the following three pairs of zones containing fixed offset
locations, regardless of the device zone size.
- primary superblock: offset 0B (and the following zone)
- first copy: offset 512G (and the following zone)
- Second copy: offset 4T (4096G, and the following zone)
If a logging zone is outside of the disk capacity, we do not record the
superblock copy.
The first copy position is much larger than for a non-zoned filesystem,
which is at 64M. This is to avoid overlapping with the log zones for
the primary superblock. This higher location is arbitrary but allows
supporting devices with very large zone sizes, plus some space around in
between.
Such large zone size is unrealistic and very unlikely to ever be seen in
real devices. Currently, SMR disks have a zone size of 256MB, and we are
expecting ZNS drives to be in the 1-4GB range, so this limit gives us
room to breathe. For now, we only allow zone sizes up to 8GB. The
maximum zone size that would still fit in the space is 256G.
The fixed location addresses are somewhat arbitrary, with the intent of
maintaining superblock reliability for smaller and larger devices, with
the preference for the latter. For this reason, there are two superblocks
under the first 1T. This should cover use cases for physical devices and
for emulated/device-mapper devices.
The superblock logging zones are reserved for superblock logging and
never used for data or metadata blocks. Note that we only reserve the
two zones per primary/copy actually used for superblock logging. We do
not reserve the ranges of zones possibly containing superblocks with the
largest supported zone size (0-16GB, 512G-528GB, 4096G-4112G).
The zones containing the fixed location offsets used to store
superblocks on a non-zoned volume are also reserved to avoid confusion.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull x86 fixes from Borislav Petkov:
- Fix the vDSO exception handling return path to disable interrupts
again.
- A fix for the CE collector to return the proper return values to its
callers which are used to convey what the collector has done with the
error address.
* tag 'x86_urgent_for_v5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/traps: Correct exc_general_protection() and math_error() return paths
RAS/CEC: Correct ce_add_elem()'s returned values
Clang doesn't like format strings that truncate a 32-bit
value to something shorter:
kernel/locking/lockdep.c:709:4: error: format specifies type 'short' but the argument has type 'int' [-Werror,-Wformat]
In this case, the warning is a slightly questionable, as it could realize
that both class->wait_type_outer and class->wait_type_inner are in fact
8-bit struct members, even though the result of the ?: operator becomes an
'int'.
However, there is really no point in printing the number as a 16-bit
'short' rather than either an 8-bit or 32-bit number, so just change
it to a normal %d.
Fixes: de8f5e4f2dc1 ("lockdep: Introduce wait-type checks")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210322115531.3987555-1-arnd@kernel.org
Commit 1dae796aabf6 ("btrfs: inode: sink parameter start and len to
check_data_csum()") replaced the start parameter to check_data_csum()
with page_offset(), but page_offset() is not meaningful for direct I/O
pages. Bring back the start parameter.
Fixes: 265d4ac03fdf ("btrfs: sink parameter start and len to check_data_csum")
CC: stable@vger.kernel.org # 5.11+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull percpu fix from Dennis Zhou:
"This contains a fix for sporadically failing atomic percpu
allocations.
I only caught it recently while I was reviewing a new series [1] and
simultaneously saw reports by btrfs in xfstests [2] and [3].
In v5.9, memcg accounting was extended to percpu done by adding a
second type of chunk. I missed an interaction with the free page float
count used to ensure we can support atomic allocations. If one type of
chunk has no free pages, but the other has enough to satisfy the free
page float requirement, we will not repopulate the free pages for the
former type of chunk. This led to the sporadically failing atomic
allocations"
Link: https://lore.kernel.org/linux-mm/20210324190626.564297-1-guro@fb.com/ [1]
Link: https://lore.kernel.org/linux-mm/20210401185158.3275.409509F4@e16-tech.com/ [2]
Link: https://lore.kernel.org/linux-mm/CAL3q7H5RNBjCi708GH7jnczAOe0BLnacT9C+OBgA-Dx9jhB6SQ@mail.gmail.com/ [3]
* 'for-5.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
percpu: make pcpu_nr_empty_pop_pages per chunk type
Commit
334872a09198 ("x86/traps: Attempt to fixup exceptions in vDSO before signaling")
added return statements which bypass calling cond_local_irq_disable().
According to
ca4c6a9858c2 ("x86/traps: Make interrupt enable/disable symmetric in C code"),
cond_local_irq_disable() is needed because the asm return code no longer
disables interrupts. Follow the existing code as an example to use "goto
exit" instead of "return" statement.
[ bp: Massage commit message. ]
Fixes: 334872a09198 ("x86/traps: Attempt to fixup exceptions in vDSO before signaling")
Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Link: https://lkml.kernel.org/r/1617902914-83245-1-git-send-email-thomas.tai@oracle.com
Since this message is printed when dynamically allocated spinlocks (e.g.
kzalloc()) are used without initialization (e.g. spin_lock_init()),
suggest to developers to check whether initialization functions for objects
were called, before making developers wonder what annotation is missing.
[ mingo: Minor tweaks to the message. ]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210321064913.4619-1-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While removing a qgroup's sysfs entry we end up taking the kernfs_mutex,
through kobject_del(), while holding the fs_info->qgroup_lock spinlock,
producing the following trace:
[821.843637] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:281
[821.843641] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 28214, name: podman
[821.843644] CPU: 3 PID: 28214 Comm: podman Tainted: G W 5.11.6 #15
[821.843646] Hardware name: Dell Inc. PowerEdge R330/084XW4, BIOS 2.11.0 12/08/2020
[821.843647] Call Trace:
[821.843650] dump_stack+0xa1/0xfb
[821.843656] ___might_sleep+0x144/0x160
[821.843659] mutex_lock+0x17/0x40
[821.843662] kernfs_remove_by_name_ns+0x1f/0x80
[821.843666] sysfs_remove_group+0x7d/0xe0
[821.843668] sysfs_remove_groups+0x28/0x40
[821.843670] kobject_del+0x2a/0x80
[821.843672] btrfs_sysfs_del_one_qgroup+0x2b/0x40 [btrfs]
[821.843685] __del_qgroup_rb+0x12/0x150 [btrfs]
[821.843696] btrfs_remove_qgroup+0x288/0x2a0 [btrfs]
[821.843707] btrfs_ioctl+0x3129/0x36a0 [btrfs]
[821.843717] ? __mod_lruvec_page_state+0x5e/0xb0
[821.843719] ? page_add_new_anon_rmap+0xbc/0x150
[821.843723] ? kfree+0x1b4/0x300
[821.843725] ? mntput_no_expire+0x55/0x330
[821.843728] __x64_sys_ioctl+0x5a/0xa0
[821.843731] do_syscall_64+0x33/0x70
[821.843733] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[821.843736] RIP: 0033:0x4cd3fb
[821.843741] RSP: 002b:000000c000906b20 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
[821.843744] RAX: ffffffffffffffda RBX: 000000c000050000 RCX: 00000000004cd3fb
[821.843745] RDX: 000000c000906b98 RSI: 000000004010942a RDI: 000000000000000f
[821.843747] RBP: 000000c000907cd0 R08: 000000c000622901 R09: 0000000000000000
[821.843748] R10: 000000c000d992c0 R11: 0000000000000206 R12: 000000000000012d
[821.843749] R13: 000000000000012c R14: 0000000000000200 R15: 0000000000000049
Fix this by removing the qgroup sysfs entry while not holding the spinlock,
since the spinlock is only meant for protection of the qgroup rbtree.
Reported-by: Stuart Shelton <srcshelton@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/7A5485BB-0628-419D-A4D3-27B1AF47E25A@gmail.com/
Fixes: 49e5fb46211de0 ("btrfs: qgroup: export qgroups in sysfs")
CC: stable@vger.kernel.org # 5.10+
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>
Pull SCSI fixes from James Bottomley:
"Seven fixes, all in drivers.
The hpsa three are the most extensive and the most problematic: it's a
packed structure misalignment that oopses on ia64 but looks like it
would also oops on quite a few non-x86 architectures.
The pm80xx is a regression and the rest are bug fixes for patches in
the misc tree"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: scsi_transport_srp: Don't block target in SRP_PORT_LOST state
scsi: target: iscsi: Fix zero tag inside a trace event
scsi: pm80xx: Fix chip initialization failure
scsi: ufs: core: Fix wrong Task Tag used in task management request UPIUs
scsi: ufs: core: Fix task management request completion timeout
scsi: hpsa: Add an assert to prevent __packed reintroduction
scsi: hpsa: Fix boot on ia64 (atomic_t alignment)
scsi: hpsa: Use __packed on individual structs, not header-wide
nr_empty_pop_pages is used to guarantee that there are some free
populated pages to satisfy atomic allocations. Accounted and
non-accounted allocations are using separate sets of chunks,
so both need to have a surplus of empty pages.
This commit makes pcpu_nr_empty_pop_pages and the corresponding logic
per chunk type.
[Dennis]
This issue came up as I was reviewing [1] and realized I missed this.
Simultaneously, it was reported btrfs was seeing failed atomic
allocations in fsstress tests [2] and [3].
[1] https://lore.kernel.org/linux-mm/20210324190626.564297-1-guro@fb.com/
[2] https://lore.kernel.org/linux-mm/20210401185158.3275.409509F4@e16-tech.com/
[3] https://lore.kernel.org/linux-mm/CAL3q7H5RNBjCi708GH7jnczAOe0BLnacT9C+OBgA-Dx9jhB6SQ@mail.gmail.com/
Fixes: 3c7be18ac9a0 ("mm: memcg/percpu: account percpu memory to memory cgroups")
Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Roman Gushchin <guro@fb.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>
ce_add_elem() uses different return values to signal a result from
adding an element to the collector. Commit in Fixes: broke the case
where the element being added is not found in the array. Correct that.
[ bp: Rewrite commit message, add kernel-doc comments. ]
Fixes: de0e0624d86f ("RAS/CEC: Check count_threshold unconditionally")
Signed-off-by: William Roche <william.roche@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/1617722939-29670-1-git-send-email-william.roche@oracle.com