Add new stats for measuring the performance of mballoc. This patch is
forked from Artem Blagodarenko's work that can be found here:

https://github.com/lustre/lustre-release/blob/master/ldiskfs/kernel_patches/patches/rhel8/ext4-simple-blockalloc.patch

This patch reorganizes the stats by cr level. This is how the output
looks like:

mballoc:
	reqs: 0
	success: 0
	groups_scanned: 0
	cr0_stats:
		hits: 0
		groups_considered: 0
		useless_loops: 0
		bad_suggestions: 0
	cr1_stats:
		hits: 0
		groups_considered: 0
		useless_loops: 0
		bad_suggestions: 0
	cr2_stats:
		hits: 0
		groups_considered: 0
		useless_loops: 0
	cr3_stats:
		hits: 0
		groups_considered: 0
		useless_loops: 0
	extents_scanned: 0
		goal_hits: 0
		2^n_hits: 0
		breaks: 0
		lost: 0
	buddies_generated: 0/40
	buddies_time_used: 0
	preallocated: 0
	discarded: 0

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20210401172129.189766-4-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Before this patch, the function parse_options() was returning
journal_devnum and journal_ioprio variables to the caller. This patch
generalizes that interface to allow parse_options to return any parsed
options to return back to the caller. In this patch series, it gets
used to capture the value of "mb_optimize_scan=%u" mount option.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20210401172129.189766-3-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

s_mb_buddies_generated gets used later in this patch series to
determine if the cr 0 and cr 1 optimziations should be performed or
not. Currently, s_mb_buddies_generated is protected under a
spin_lock. In the allocation path, it is better if we don't depend on
the lock and instead read the value atomically. In order to do that,
we drop s_bal_lock altogether and we convert the only two protected
fields by it s_mb_buddies_generated and s_mb_generation_time to atomic
type.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20210401172129.189766-2-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Commit <50122847> ("ext4: fix check to prevent initializing reserved
inodes") check the block group zero and prevent initializing reserved
inodes. But in some special cases, the reserved inode may not all belong
to the group zero, it may exist into the second group if we format
filesystem below.

  mkfs.ext4 -b 4096 -g 8192 -N 1024 -I 4096 /dev/sda

So, it will end up triggering a false positive report of a corrupted
file system. This patch fix it by avoid check reserved inodes if no free
inode blocks will be zeroed.

Cc: stable@kernel.org
Fixes: 50122847

 ("ext4: fix check to prevent initializing reserved inodes")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210331121516.2243099-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Building with 'make W=1' shows a harmless -Wempty-body warning:

fs/jbd2/recovery.c: In function 'fc_do_one_pass':
fs/jbd2/recovery.c:267:75: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
  267 |                 jbd_debug(3, "Fast commit replay failed, err = %d\n", err);
      |                                                                           ^

Change the empty dprintk() macros to no_printk(), which avoids this
warning and adds format string checking.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210322102152.95684-1-arnd@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Matching names with casefolded encrypting directories requires
decrypting entries to confirm case since we are case preserving. We can
avoid needing to decrypt if our hash values don't match.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Link: https://lore.kernel.org/r/20210319073414.1381041-3-drosen@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

This adds support for encryption with casefolding.

Since the name on disk is case preserving, and also encrypted, we can no
longer just recompute the hash on the fly. Additionally, to avoid
leaking extra information from the hash of the unencrypted name, we use
siphash via an fscrypt v2 policy.

The hash is stored at the end of the directory entry for all entries
inside of an encrypted and casefolded directory apart from those that
deal with '.' and '..'. This way, the change is backwards compatible
with existing ext4 filesystems.

[ Changed to advertise this feature via the file:
  /sys/fs/ext4/features/encrypted_casefold -- TYT ]

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20210319073414.1381041-2-drosen@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Removes braces to follow the coding style.

Signed-off-by: Milan Djurovic <mdjurovic@zohomail.com>
Link: https://lore.kernel.org/r/20210316052953.67616-1-mdjurovic@zohomail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

A number of tracepoint instances have been removed from ext4 by past
patches but the definitions of those tracepoints have not.

All instances of ext4_ext_in_cache and ext4_ext_put_in_cache were
removed by commit 69eb33dc ("ext4: remove single extent cache").
ext4_get_reserved_cluster_alloc was removed by commit b6bf9171
("ext4: reduce reserved cluster count by number of allocated
clusters").  ext4_find_delalloc_range was removed by commit
7d1b1fbc ("ext4: reimplement ext4_find_delay_alloc_range on extent
status tree").

All instances of ext4_direct_IO_enter and ext4_direct_IO_exit were
removed by commit 378f32ba

 ("ext4: introduce direct I/O write
using iomap infrastructure").

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20210216191634.20957-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Some members of transaction_t are allowed to be read without any lock
being held if accessed from the correct context.  We used LockDoc's
findings to determine those members.  Each member of them is marked
with a short comment: "no lock needed for jbd2 thread".

Signed-off-by: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
Signed-off-by: Horst Schirmeier <horst.schirmeier@tu-dortmund.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210211171410.17984-1-alexander.lochmann@tu-dortmund.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Some members of transaction_t are allowed to be read without any lock
being held if consistency doesn't matter.  Based on LockDoc's
findings, we extended the locking documentation of those members.
Each one of them is marked with a short comment: "no lock for quick
racy checks".

Signed-off-by: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
Signed-off-by: Horst Schirmeier <horst.schirmeier@tu-dortmund.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/ad82c7a9-a624-4ed5-5ada-a6410c44c0b3@tu-dortmund.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210207190425.38107-7-chaitanya.kulkarni@wdc.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210207190425.38107-6-chaitanya.kulkarni@wdc.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Pull ext4 fixes from Ted Ts'o:
 "Miscellaneous ext4 bug fixes for v5.12"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: initialize ret to suppress smatch warning
  ext4: stop inode update before return
  ext4: fix rename whiteout with fast commit
  ext4: fix timer use-after-free on failed mount
  ext4: fix potential error in ext4_do_update_inode
  ext4: do not try to set xattr into ea_inode if value is empty
  ext4: do not iput inode under running transaction in ext4_rename()
  ext4: find old entry again if failed to rename whiteout
  ext4: fix error handling in ext4_end_enable_verity()
  ext4: fix bh ref count on error paths
  fs/ext4: fix integer overflow in s_log_groups_per_flex
  ext4: add reclaim checks to xattr code
  ext4: shrink race window in ext4_should_retry_alloc()

Pull io_uring followup fixes from Jens Axboe:

 - The SIGSTOP change from Eric, so we properly ignore that for
   PF_IO_WORKER threads.

 - Disallow sending signals to PF_IO_WORKER threads in general, we're
   not interested in having them funnel back to the io_uring owning
   task.

 - Stable fix from Stefan, ensuring we properly break links for short
   send/sendmsg recv/recvmsg if MSG_WAITALL is set.

 - Catch and loop when needing to run task_work before a PF_IO_WORKER
   threads goes to sleep.

* tag 'io_uring-5.12-2021-03-21' of git://git.kernel.dk/linux-block:
  io_uring: call req_set_fail_links() on short send[msg]()/recv[msg]() with MSG_WAITALL
  io-wq: ensure task is running before processing task_work
  signal: don't allow STOP on PF_IO_WORKER threads
  signal: don't allow sending any signals to PF_IO_WORKER threads

Pull staging and IIO driver fixes from Greg KH:
 "Some small staging and IIO driver fixes:

   - MAINTAINERS changes for the move of the staging mailing list

   - comedi driver fixes to get request_irq() to work correctly

   - counter driver fixes for reported issues with iio devices

   - tiny iio driver fixes for reported issues.

  All of these have been in linux-next with no reported problems"

* tag 'staging-5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: vt665x: fix alignment constraints
  staging: comedi: cb_pcidas64: fix request_irq() warn
  staging: comedi: cb_pcidas: fix request_irq() warn
  MAINTAINERS: move the staging subsystem to lists.linux.dev
  MAINTAINERS: move some real subsystems off of the staging mailing list
  iio: gyro: mpu3050: Fix error handling in mpu3050_trigger_handler
  iio: hid-sensor-temperature: Fix issues of timestamp channel
  iio: hid-sensor-humidity: Fix alignment issue of timestamp channel
  counter: stm32-timer-cnt: fix ceiling miss-alignment with reload register
  counter: stm32-timer-cnt: fix ceiling write max value
  counter: stm32-timer-cnt: Report count function when SLAVE_MODE_DISABLED
  iio: adc: ab8500-gpadc: Fix off by 10 to 3
  iio:adc:stm32-adc: Add HAS_IOMEM dependency
  iio: adis16400: Fix an error code in adis16400_initial_setup()
  iio: adc: adi-axi-adc: add proper Kconfig dependencies
  iio: adc: ad7949: fix wrong ADC result due to incorrect bit mask
  iio: hid-sensor-prox: Fix scale not correct issue
  iio:adc:qcom-spmi-vadc: add default scale to LR_MUX2_BAT_ID channel

Pull USB and Thunderbolt driver fixes from Greg KH:
 "Here are some small Thunderbolt and USB driver fixes for some reported
  issues:

   - thunderbolt fixes for minor problems

   - typec fixes for power issues

   - usb-storage quirk addition

   - usbip bugfix

   - dwc3 bugfix when stopping transfers

   - cdnsp bugfix for isoc transfers

   - gadget use-after-free fix

  All have been in linux-next this week with no reported issues"

* tag 'usb-5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: typec: tcpm: Skip sink_cap query only when VDM sm is busy
  usb: dwc3: gadget: Prevent EP queuing while stopping transfers
  usb: typec: tcpm: Invoke power_supply_changed for tcpm-source-psy-
  usb: typec: Remove vdo[3] part of tps6598x_rx_identity_reg struct
  usb-storage: Add quirk to defeat Kindle's automatic unload
  usb: gadget: configfs: Fix KASAN use-after-free
  usbip: Fix incorrect double assignment to udc->ud.tcp_rx
  usb: cdnsp: Fixes incorrect value in ISOC TRB
  thunderbolt: Increase runtime PM reference count on DP tunnel discovery
  thunderbolt: Initialize HopID IDAs in tb_switch_alloc()

Pull irq fix from Ingo Molnar:
 "A change to robustify force-threaded IRQ handlers to always disable
  interrupts, plus a DocBook fix.

  The force-threaded IRQ handler change has been accelerated from the
  normal schedule of such a change to keep the bad pattern/workaround of
  spin_lock_irqsave() in handlers or IRQF_NOTHREAD as a kludge from
  spreading"

* tag 'irq-urgent-2021-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Disable interrupts for force threaded handlers
  genirq/irq_sim: Fix typos in kernel doc (fnode -> fwnode)

Pull perf fixes from Ingo Molnar:
 "Boundary condition fixes for bugs unearthed by the perf fuzzer"

* tag 'perf-urgent-2021-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Fix unchecked MSR access error caused by VLBR_EVENT
  perf/x86/intel: Fix a crash caused by zero PEBS status

Pull locking fixes from Ingo Molnar:

 - Get static calls & modules right. Hopefully.

 - WW mutex fixes

* tag 'locking-urgent-2021-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  static_call: Fix static_call_update() sanity check
  static_call: Align static_call_is_init() patching condition
  static_call: Fix static_call_set_init()
  locking/ww_mutex: Fix acquire/release imbalance in ww_acquire_init()/ww_acquire_fini()
  locking/ww_mutex: Simplify use_ww_ctx & ww_ctx handling

Pull EFI fixes from Ingo Molnar:

 - another missing RT_PROP table related fix, to ensure that the
   efivarfs pseudo filesystem fails gracefully if variable services
   are unsupported

 - use the correct alignment for literal EFI GUIDs

 - fix a use after unmap issue in the memreserve code

* tag 'efi-urgent-2021-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: use 32-bit alignment for efi_guid_t literals
  firmware/efi: Fix a use after bug in efi_mem_reserve_persistent
  efivars: respect EFI_UNSUPPORTED return from firmware

Pull x86 fixes from Borislav Petkov:
 "The freshest pile of shiny x86 fixes for 5.12:

   - Add the arch-specific mapping between physical and logical CPUs to
     fix devicetree-node lookups

   - Restore the IRQ2 ignore logic

   - Fix get_nr_restart_syscall() to return the correct restart syscall
     number. Split in a 4-patches set to avoid kABI breakage when
     backporting to dead kernels"

* tag 'x86_urgent_for_v5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic/of: Fix CPU devicetree-node lookups
  x86/ioapic: Ignore IRQ2 again
  x86: Introduce restart_block->arch_data to remove TS_COMPAT_RESTART
  x86: Introduce TS_COMPAT_RESTART to fix get_nr_restart_syscall()
  x86: Move TS_COMPAT back to asm/thread_info.h
  kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data()

Pull powerpc fixes from Michael Ellerman:

 - Fix a possible stack corruption and subsequent DLPAR failure in the
   rpadlpar_io PCI hotplug driver

 - Two build fixes for uncommon configurations

Thanks to Christophe Leroy and Tyrel Datwyler.

* tag 'powerpc-5.12-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  PCI: rpadlpar: Fix potential drc_name corruption in store functions
  powerpc: Force inlining of cpu_has_feature() to avoid build failure
  powerpc/vdso32: Add missing _restgpr_31_x to fix build failure

Without that it's not safe to use them in a linked combination with
others.

Now combinations like IORING_OP_SENDMSG followed by IORING_OP_SPLICE
should be possible.

We already handle short reads and writes for the following opcodes:

- IORING_OP_READV
- IORING_OP_READ_FIXED
- IORING_OP_READ
- IORING_OP_WRITEV
- IORING_OP_WRITE_FIXED
- IORING_OP_WRITE
- IORING_OP_SPLICE
- IORING_OP_TEE

Now we have it for these as well:

- IORING_OP_SENDMSG
- IORING_OP_SEND
- IORING_OP_RECVMSG
- IORING_OP_RECV

For IORING_OP_RECVMSG we also check for the MSG_TRUNC and MSG_CTRUNC
flags in order to call req_set_fail_links().

There might be applications arround depending on the behavior
that even short send[msg]()/recv[msg]() retuns continue an
IOSQE_IO_LINK chain.

It's very unlikely that such applications pass in MSG_WAITALL,
which is only defined in 'man 2 recvmsg', but not in 'man 2 sendmsg'.

It's expected that the low level sock_sendmsg() call just ignores
MSG_WAITALL, as MSG_ZEROCOPY is also ignored without explicitly set
SO_ZEROCOPY.

We also expect the caller to know about the implicit truncation to
MAX_RW_COUNT, which we don't detect.

cc: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/c4e1a4cc0d905314f4d5dc567e65a7b09621aab3.1615908477.git.metze@samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Mark the current task as running if we need to run task_work from the
io-wq threads as part of work handling. If that is the case, then return
as such so that the caller can appropriately loop back and reset if it
was part of a going-to-sleep flush.

Fixes: 3bfe6106

 ("io-wq: fork worker threads from original task")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Just like we don't allow normal signals to IO threads, don't deliver a
STOP to a task that has PF_IO_WORKER set. The IO threads don't take
signals in general, and have no means of flushing out a stop either.

Longer term, we may want to look into allowing stop of these threads,
as it relates to eg process freezing. For now, this prevents a spin
issue if a SIGSTOP is delivered to the parent task.

Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

They don't take signals individually, and even if they share signals with
the parent task, don't allow them to be delivered through the worker
thread. Linux does allow this kind of behavior for regular threads, but
it's really a compatability thing that we need not care about for the IO
threads.

Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

The inode update should be stopped before returing the error code.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Link: https://lore.kernel.org/r/20210117085732.93788-1-bianpan2016@163.com
Fixes: 8016e29f

 ("ext4: fast commit recovery path")
Cc: stable@kernel.org
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

This patch adds rename whiteout support in fast commits. Note that the
whiteout object that gets created is actually char device. Which
imples, the function ext4_inode_journal_mode(struct inode *inode)
would return "JOURNAL_DATA" for this inode. This has a consequence in
fast commit code that it will make creation of the whiteout object a
fast-commit ineligible behavior and thus will fall back to full
commits. With this patch, this can be observed by running fast commits
with rename whiteout and seeing the stats generated by ext4_fc_stats
tracepoint as follows:

ext4_fc_stats: dev 254:32 fc ineligible reasons:
XATTR:0, CROSS_RENAME:0, JOURNAL_FLAG_CHANGE:0, NO_MEM:0, SWAP_BOOT:0,
RESIZE:0, RENAME_DIR:0, FALLOC_RANGE:0, INODE_JOURNAL_DATA:16;
num_commits:6, ineligible: 6, numblks: 3

So in short, this patch guarantees that in case of rename whiteout, we
fall back to full commits.

Amir mentioned that instead of creating a new whiteout object for
every rename, we can create a static whiteout object with irrelevant
nlink. That will make fast commits to not fall back to full
commit. But until this happens, this patch will ensure correctness by
falling back to full commits.

Fixes: 8016e29f

 ("ext4: fast commit recovery path")
Cc: stable@kernel.org
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20210316221921.1124955-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

When filesystem mount fails because of corrupted filesystem we first
cancel the s_err_report timer reminding fs errors every day and only
then we flush s_error_work. However s_error_work may report another fs
error and re-arm timer thus resulting in timer use-after-free. Fix the
problem by first flushing the work and only after that canceling the
s_err_report timer.

Reported-by:  <syzbot+628472a2aac693ab0fcd@syzkaller.appspotmail.com>
Fixes: 2d01ddc8

 ("ext4: save error info to sb through journal if available")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210315165906.2175-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

If set_large_file = 1 and errors occur in ext4_handle_dirty_metadata(),
the error code will be overridden, go to out_brelse to avoid this
situation.

Signed-off-by: Shijie Luo <luoshijie1@huawei.com>
Link: https://lore.kernel.org/r/20210312065051.36314-1-luoshijie1@huawei.com
Cc: stable@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Syzbot report a warning that ext4 may create an empty ea_inode if set
an empty extent attribute to a file on the file system which is no free
blocks left.

  WARNING: CPU: 6 PID: 10667 at fs/ext4/xattr.c:1640 ext4_xattr_set_entry+0x10f8/0x1114 fs/ext4/xattr.c:1640
  ...
  Call trace:
   ext4_xattr_set_entry+0x10f8/0x1114 fs/ext4/xattr.c:1640
   ext4_xattr_block_set+0x1d0/0x1b1c fs/ext4/xattr.c:1942
   ext4_xattr_set_handle+0x8a0/0xf1c fs/ext4/xattr.c:2390
   ext4_xattr_set+0x120/0x1f0 fs/ext4/xattr.c:2491
   ext4_xattr_trusted_set+0x48/0x5c fs/ext4/xattr_trusted.c:37
   __vfs_setxattr+0x208/0x23c fs/xattr.c:177
  ...

Now, ext4 try to store extent attribute into an external inode if
ext4_xattr_block_set() return -ENOSPC, but for the case of store an
empty extent attribute, store the extent entry into the extent
attribute block is enough. A simple reproduce below.

  fallocate test.img -l 1M
  mkfs.ext4 -F -b 2048 -O ea_inode test.img
  mount test.img /mnt
  dd if=/dev/zero of=/mnt/foo bs=2048 count=500
  setfattr -n "user.test" /mnt/foo

Reported-by:  <syzbot+98b881fdd8ebf45ab4ae@syzkaller.appspotmail.com>
Fixes: 9c6e7853

 ("ext4: reserve space for xattr entries/names")
Cc: stable@kernel.org
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210305120508.298465-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

In ext4_rename(), when RENAME_WHITEOUT failed to add new entry into
directory, it ends up dropping new created whiteout inode under the
running transaction. After commit <9b88f9fb

> ("ext4: Do not iput inode
under running transaction"), we follow the assumptions that evict() does
not get called from a transaction context but in ext4_rename() it breaks
this suggestion. Although it's not a real problem, better to obey it, so
this patch add inode to orphan list and stop transaction before final
iput().

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210303131703.330415-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

If we failed to add new entry on rename whiteout, we cannot reset the
old->de entry directly, because the old->de could have moved from under
us during make indexed dir. So find the old entry again before reset is
needed, otherwise it may corrupt the filesystem as below.

  /dev/sda: Entry '00000001' in ??? (12) has deleted/unused inode 15. CLEARED.
  /dev/sda: Unattached inode 75
  /dev/sda: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.

Fixes: 6b4b8e6b

 ("ext4: fix bug for rename with RENAME_WHITEOUT")
Cc: stable@vger.kernel.org
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210303131703.330415-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

With interrupt force threading all device interrupt handlers are invoked
from kernel threads. Contrary to hard interrupt context the invocation only
disables bottom halfs, but not interrupts. This was an oversight back then
because any code like this will have an issue:

thread(irq_A)
  irq_handler(A)
    spin_lock(&foo->lock);

interrupt(irq_B)
  irq_handler(B)
    spin_lock(&foo->lock);

This has been triggered with networking (NAPI vs. hrtimers) and console
drivers where printk() happens from an interrupt which interrupted the
force threaded handler.

Now people noticed and started to change the spin_lock() in the handler to
spin_lock_irqsave() which affects performance or add IRQF_NOTHREAD to the
interrupt request which in turn breaks RT.

Fix the root cause and not the symptom and disable interrupts before
invoking the force threaded handler which preserves the regular semantics
and the usefulness of the interrupt force threading as a general debugging
tool.

For not RT this is not changing much, except that during the execution of
the threaded handler interrupts are delayed until the handler
returns. Vs. scheduling and softirq processing there is no difference.

For RT kernels there is no issue.

Fixes: 8d32a307

 ("genirq: Provide forced interrupt threading")
Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Johan Hovold <johan@kernel.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20210317143859.513307808@linutronix.de

Pull RISC-V fixes from Palmer Dabbelt:
 "A handful of fixes for 5.12:

   - fix the SBI remote fence numbers for hypervisor fences, which had
     been transcribed in the wrong order in Linux. These fences are only
     used with the KVM patches applied.

   - fix a whole host of build warnings, these should have no functional
     change.

   - fix init_resources() to prevent an off-by-one error from causing an
     out-of-bounds array reference. This was manifesting during boot on
     vexriscv.

   - ensure the KASAN mappings are visible before proceeding to use
     them"

* tag 'riscv-for-linus-5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Correct SPARSEMEM configuration
  RISC-V: kasan: Declare kasan_shallow_populate() static
  riscv: Ensure page table writes are flushed when initializing KASAN vmalloc
  RISC-V: Fix out-of-bounds accesses in init_resources()
  riscv: Fix compilation error with Canaan SoC
  ftrace: Fix spelling mistake "disabed" -> "disabled"
  riscv: fix bugon.cocci warnings
  riscv: process: Fix no prototype for arch_dup_task_struct
  riscv: ftrace: Use ftrace_get_regs helper
  riscv: process: Fix no prototype for show_regs
  riscv: syscall_table: Reduce W=1 compilation warnings noise
  riscv: time: Fix no prototype for time_init
  riscv: ptrace: Fix no prototype warnings
  riscv: sbi: Fix comment of __sbi_set_timer_v01
  riscv: irq: Fix no prototype warning
  riscv: traps: Fix no prototype warnings
  RISC-V: correct enum sbi_ext_rfence_fid

Pull cifs fixes from Steve French:
 "Five cifs/smb3 fixes - three for stable, including an important ACL
  fix and security signature fix"

* tag '5.12-rc3-smb3' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix allocation size on newly created files
  cifs: warn and fail if trying to use rootfs without the config option
  fs/cifs/: fix misspellings using codespell tool
  cifs: Fix preauth hash corruption
  cifs: update new ACE pointer after populate_new_aces.

Pull SCSI fixes from James Bottomley:
 "Eight fixes, all in drivers, all fairly minor either being fixes in
  error legs, memory leaks on teardown, context errors or semantic
  problems"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: mpt3sas: Do not use GFP_KERNEL in atomic context
  scsi: ufs: ufs-mediatek: Correct operator & -> &&
  scsi: sd_zbc: Update write pointer offset cache
  scsi: lpfc: Fix some error codes in debugfs
  scsi: qla2xxx: Fix broken #endif placement
  scsi: st: Fix a use after free in st_open()
  scsi: myrs: Fix a double free in myrs_cleanup()
  scsi: ibmvfc: Free channel_setup_buf during device tear down