It is very annoying to have two block layer functions which share same
name, so rename blk_attempt_bio_merge in blk-mq.c as
blk_mq_attempt_bio_merge.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211111085134.345235-3-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

blk_mq_sched_bio_merge is only called from blk-mq.c:blk_attempt_bio_merge(),
which is called when queue usage counter is grabbed already:

1) blk_mq_get_new_requests()

2) blk_mq_get_request()
- cached request in current plug owns one queue usage counter

So don't grab ->q_usage_counter in blk_mq_sched_bio_merge(), and more
importantly this nest way causes hang in blk_mq_freeze_queue_wait().

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211111085134.345235-2-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

The naming got changed as part of a revision of the patchset, but the
kerneldoc apparently never got updated. Fix it.
Reported-by: Nkernel test robot <lkp@intel.com>
Fixes: a2247f19 ("block: Add independent access ranges support")
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Now that we have done a spring cleaning on all drivers and added
error checking / handling, let's keep it that way and ensure
no new drivers fail to stick with it.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20211110002949.999380-1-mcgrof@kernel.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

kernel test robot reports that we now trigger some sparse warnings:

block/blk-mq.h:169:32: sparse: sparse: restricted req_flags_t degrades to integer
block/blk-mq.h:169:32: sparse: sparse: restricted req_flags_t degrades to integer
block/blk-mq.h:169:32: sparse: sparse: restricted req_flags_t degrades to integer

which is due to ->rq_flags being an unsigned int, rather than the
stronger type req_flags_t enum.

Change the type to req_flags_t to silence this warning.

Fixes: 56f8da64 ("block: add rq_flags to struct blk_mq_alloc_data")
Reported-by: Nkernel test robot <lkp@intel.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

When BLKZEROOUT ioctl and data read race, the data read leaves stale
page cache. To avoid the stale page cache, hold invalidate_lock of the
block device file mapping. The stale page cache is observed when
blktests test case block/009 is modified to call "blkdiscard -z" command
and repeated hundreds of times.

This patch can be applied back to the stable kernel version v5.15.y.
Rework is required for older stable kernels.

Fixes: 22dd6d35 ("block: invalidate the page cache when issuing BLKZEROOUT")
Signed-off-by: NShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: NJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211109104723.835533-3-shinichiro.kawasaki@wdc.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

When BLKDISCARD ioctl and data read race, the data read leaves stale
page cache. To avoid the stale page cache, hold invalidate_lock of the
block device file mapping. The stale page cache is observed when
blktests test case block/009 is repeated hundreds of times.

This patch can be applied back to the stable kernel version v5.15.y
with slight patch edit. Rework is required for older stable kernels.

Fixes: 351499a1 ("block: Invalidate cache on discard v2")
Signed-off-by: NShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: NJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211109104723.835533-2-shinichiro.kawasaki@wdc.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Pull more block driver updates from Jens Axboe:

 - Last series adding error handling support for add_disk() in drivers.
   After this one, and once the SCSI side has been merged, we can
   finally annotate add_disk() as must_check. (Luis)

 - bcache fixes (Coly)

 - zram fixes (Ming)

 - ataflop locking fix (Tetsuo)

 - nbd fixes (Ye, Yu)

 - MD merge via Song
      - Cleanup (Yang)
      - sysfs fix (Guoqing)

 - Misc fixes (Geert, Wu, luo)

* tag 'for-5.16/drivers-2021-11-09' of git://git.kernel.dk/linux-block: (34 commits)
  bcache: Revert "bcache: use bvec_virt"
  ataflop: Add missing semicolon to return statement
  floppy: address add_disk() error handling on probe
  ataflop: address add_disk() error handling on probe
  block: update __register_blkdev() probe documentation
  ataflop: remove ataflop_probe_lock mutex
  mtd/ubi/block: add error handling support for add_disk()
  block/sunvdc: add error handling support for add_disk()
  z2ram: add error handling support for add_disk()
  nvdimm/pmem: use add_disk() error handling
  nvdimm/pmem: cleanup the disk if pmem_release_disk() is yet assigned
  nvdimm/blk: add error handling support for add_disk()
  nvdimm/blk: avoid calling del_gendisk() on early failures
  nvdimm/btt: add error handling support for add_disk()
  nvdimm/btt: use goto error labels on btt_blk_init()
  loop: Remove duplicate assignments
  drbd: Fix double free problem in drbd_create_device
  nvdimm/btt: do not call del_gendisk() if not needed
  bcache: fix use-after-free problem in bcache_device_free()
  zram: replace fsync_bdev with sync_blockdev
  ...

Pull block fixes from Jens Axboe:

 - Set of fixes for the batched tag allocation (Ming, me)

 - add_disk() error handling fix (Luis)

 - Nested queue quiesce fixes (Ming)

 - Shared tags init error handling fix (Ye)

 - Misc cleanups (Jean, Ming, me)

* tag 'for-5.16/block-2021-11-09' of git://git.kernel.dk/linux-block:
  nvme: wait until quiesce is done
  scsi: make sure that request queue queiesce and unquiesce balanced
  scsi: avoid to quiesce sdev->request_queue two times
  blk-mq: add one API for waiting until quiesce is done
  blk-mq: don't free tags if the tag_set is used by other device in queue initialztion
  block: fix device_add_disk() kobject_create_and_add() error handling
  block: ensure cached plug request matches the current queue
  block: move queue enter logic into blk_mq_submit_bio()
  block: make bio_queue_enter() fast-path available inline
  block: split request allocation components into helpers
  block: have plug stored requests hold references to the queue
  blk-mq: update hctx->nr_active in blk_mq_end_request_batch()
  blk-mq: add RQF_ELV debug entry
  blk-mq: only try to run plug merge if request has same queue with incoming bio
  block: move RQF_ELV setting into allocators
  dm: don't stop request queue after the dm device is suspended
  block: replace always false argument with 'false'
  block: assign correct tag before doing prefetch of request
  blk-mq: fix redundant check of !e expression

Pull more bdev size updates from Jens Axboe:
 "Two followup changes for the bdev-size series from this merge window:

   - Add loff_t cast to bdev_nr_bytes() (Christoph)

   - Use bdev_nr_bytes() consistently for the block parts at least (me)"

* tag 'for-5.16/bdev-size-2021-11-09' of git://git.kernel.dk/linux-block:
  block: use new bdev_nr_bytes() helper for blkdev_{read,write}_iter()
  block: add a loff_t cast to bdev_nr_bytes

Pull io_uring fixes from Jens Axboe:
 "Minor fixes that should go into the 5.16 release:

   - Fix max worker setting not working correctly on NUMA (Beld)

   - Correctly return current setting for max workers if zeroes are
     passed in (Pavel)

   - io_queue_sqe_arm_apoll() cleanup, as identified during the initial
     merge (Pavel)

   - Misc fixes (Nghia, me)"

* tag 'io_uring-5.16-2021-11-09' of git://git.kernel.dk/linux-block:
  io_uring: honour zeroes as io-wq worker limits
  io_uring: remove dead 'sqe' store
  io_uring: remove redundant assignment to ret in io_register_iowq_max_workers()
  io-wq: fix max-workers not correctly set on multi-node system
  io_uring: clean up io_queue_sqe_arm_apoll

Merge tag 'for-5.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Add DM core support for emitting audit events through the audit
   subsystem. Also enhance both the integrity and crypt targets to emit
   events to via dm-audit.

 - Various other simple code improvements and cleanups.

* tag 'for-5.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm table: log table creation error code
  dm: make workqueue names device-specific
  dm writecache: Make use of the helper macro kthread_run()
  dm crypt: Make use of the helper macro kthread_run()
  dm verity: use bvec_kmap_local in verity_for_bv_block
  dm log writes: use memcpy_from_bvec in log_writes_map
  dm integrity: use bvec_kmap_local in __journal_read_write
  dm integrity: use bvec_kmap_local in integrity_metadata
  dm: add add_disk() error handling
  dm: Remove redundant flush_workqueue() calls
  dm crypt: log aead integrity violations to audit subsystem
  dm integrity: log audit events for dm-integrity target
  dm: introduce audit event module for device mapper

Pull dma-mapping updates from Christoph Hellwig:
 "Just a small set of changes this time. The request dma_direct_alloc
  cleanups are still under review and haven't made the cut.

  Summary:

   - convert sparc32 to the generic dma-direct code

   - use bitmap_zalloc (Christophe JAILLET)"

* tag 'dma-mapping-5.16' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: use 'bitmap_zalloc()' when applicable
  sparc32: use DMA_DIRECT_REMAP
  sparc32: remove dma_make_coherent
  sparc32: remove the call to dma_make_coherent in arch_dma_free

Pull overlayfs updates from Miklos Szeredi:

 - Fix a regression introduced in the last cycle

 - Fix a use-after-free in the AIO path

 - Fix a bogus warning reported by syzbot

* tag 'ovl-update-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: fix filattr copy-up failure
  ovl: fix warning in ovl_create_real()
  ovl: fix use after free in struct ovl_aio_req

Pull fuse updates from Miklos Szeredi:

 - Fix a possible of deadlock in case inode writeback is in progress
   during dentry reclaim

 - Fix a crash in case of page stealing

 - Selectively invalidate cached attributes, possibly improving
   performance

 - Allow filesystems to disable data flushing from ->flush()

 - Misc fixes and cleanups

* tag 'fuse-update-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (23 commits)
  fuse: fix page stealing
  virtiofs: use strscpy for copying the queue name
  fuse: add FOPEN_NOFLUSH
  fuse: only update necessary attributes
  fuse: take cache_mask into account in getattr
  fuse: add cache_mask
  fuse: move reverting attributes to fuse_change_attributes()
  fuse: simplify local variables holding writeback cache state
  fuse: cleanup code conditional on fc->writeback_cache
  fuse: fix attr version comparison in fuse_read_update_size()
  fuse: always invalidate attributes after writes
  fuse: rename fuse_write_update_size()
  fuse: don't bump attr_version in cached write
  fuse: selective attribute invalidation
  fuse: don't increment nlink in link()
  fuse: decrement nlink on overwriting rename
  fuse: simplify __fuse_write_file_get()
  fuse: move fuse_invalidate_attr() into fuse_update_ctime()
  fuse: delete redundant code
  fuse: use kmap_local_page()
  ...

Pull orangefs fixes from Mike Marshall:

 - fix sb refcount leak when allocate sb info failed (Chenyuan Mi)

 - fix error return code of orangefs_revalidate_lookup() (Jia-Ju Bai)

 - remove redundant initialization of variable ret (Colin Ian King)

* tag 'for-linus-5.16-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  orangefs: Fix sb refcount leak when allocate sb info failed.
  fs: orangefs: fix error return code of orangefs_revalidate_lookup()
  orangefs: Remove redundant initialization of variable ret

Pull 9p updates from Dominique Martinet:
 "Fixes, netfs read support and checkpatch rewrite:

   - fix syzcaller uninitialized value usage after missing error check

   - add module autoloading based on transport name

   - convert cached reads to use netfs helpers

   - adjust readahead based on transport msize

   - and many, many checkpatch.pl warning fixes..."

* tag '9p-for-5.16-rc1' of git://github.com/martinetd/linux:
  9p: fix a bunch of checkpatch warnings
  9p: set readahead and io size according to maxsize
  9p p9mode2perm: remove useless strlcpy and check sscanf return code
  9p v9fs_parse_options: replace simple_strtoul with kstrtouint
  9p: fix file headers
  fs/9p: fix indentation and Add missing a blank line after declaration
  fs/9p: fix warnings found by checkpatch.pl
  9p: fix minor indentation and codestyle
  fs/9p: cleanup: opening brace at the beginning of the next line
  9p: Convert to using the netfs helper lib to do reads and caching
  fscache_cookie_enabled: check cookie is valid before accessing it
  net/9p: autoload transport modules
  9p/net: fix missing error check in p9_check_errors

Merge more updates from Andrew Morton:
 "87 patches.

  Subsystems affected by this patch series: mm (pagecache and hugetlb),
  procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
  init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
  sysvfs, kcov, gdb, resource, selftests, and ipc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
  ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
  ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
  selftests/kselftest/runner/run_one(): allow running non-executable files
  virtio-mem: disallow mapping virtio-mem memory via /dev/mem
  kernel/resource: disallow access to exclusive system RAM regions
  kernel/resource: clean up and optimize iomem_is_exclusive()
  scripts/gdb: handle split debug for vmlinux
  kcov: replace local_irq_save() with a local_lock_t
  kcov: avoid enable+disable interrupts if !in_task()
  kcov: allocate per-CPU memory on the relevant node
  Documentation/kcov: define `ip' in the example
  Documentation/kcov: include types.h in the example
  sysv: use BUILD_BUG_ON instead of runtime check
  kernel/fork.c: unshare(): use swap() to make code cleaner
  seq_file: fix passing wrong private data
  seq_file: move seq_escape() to a header
  signal: remove duplicate include in signal.h
  crash_dump: remove duplicate include in crash_dump.h
  crash_dump: fix boolreturn.cocci warning
  hfs/hfsplus: use WARN_ON for sanity check
  ...

Compilation of ipc/ipc_sysctl.c is controlled by
obj-$(CONFIG_SYSVIPC_SYSCTL)
[see ipc/Makefile]

And CONFIG_SYSVIPC_SYSCTL depends on SYSCTL
[see init/Kconfig]

An SYSCTL is selected by PROC_SYSCTL.
[see fs/proc/Kconfig]

Thus: #ifndef CONFIG_PROC_SYSCTL in ipc/ipc_sysctl.c is impossible, the
fallback can be removed.

Link: https://lkml.kernel.org/r/20210918145337.3369-1-manfred@colorfullife.comSigned-off-by: NManfred Spraul <manfred@colorfullife.com>
Reviewed-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: NDavidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This commit removes the requirement to be root to modify sem_next_id,
msg_next_id and shm_next_id and checks checkpoint_restore_ns_capable
instead.

Since those files are specific to the IPC namespace, there is no reason
they should require root privileges.  This is similar to ns_last_pid,
which also only checks checkpoint_restore_ns_capable.

[akpm@linux-foundation.org: ipc/ipc_sysctl.c needs capability.h for checkpoint_restore_ns_capable()]

Link: https://lkml.kernel.org/r/20210916163717.3179496-1-mclapinski@google.comSigned-off-by: NMichal Clapinski <mclapinski@google.com>
Reviewed-by: NDavidlohr Bueso <dbueso@suse.de>
Reviewed-by: NManfred Spraul <manfred@colorfullife.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When running a test program, 'run_one()' checks if the program has the
execution permission and fails if it doesn't.  However, it's easy to
mistakenly lose the permissions, as some common tools like 'diff' don't
support the permission change well[1].  Compared to that, making mistakes
in the test program's path would only rare, as those are explicitly listed
in 'TEST_PROGS'.  Therefore, it might make more sense to resolve the
situation on our own and run the program.

For this reason, this commit makes the test program runner function still
print the warning message but to try parsing the interpreter of the
program and to explicitly run it with the interpreter, in this case.

[1] https://lore.kernel.org/mm-commits/YRJisBs9AunccCD4@kroah.com/

Link: https://lkml.kernel.org/r/20210810164534.25902-1-sj38.park@gmail.comSigned-off-by: NSeongJae Park <sjpark@amazon.de>
Suggested-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We don't want user space to be able to map virtio-mem device memory
directly (e.g., via /dev/mem) in order to have guarantees that in a sane
setup we'll never accidentially access unplugged memory within the
device-managed region of a virtio-mem device, just as required by the
virtio-spec.

As soon as the virtio-mem driver is loaded, the device region is visible
in /proc/iomem via the parent device region.  From that point on user
space is aware of the device region and we want to disallow mapping
anything inside that region (where we will dynamically (un)plug memory)
until the driver has been unloaded cleanly and e.g., another driver might
take over.

By creating our parent IORESOURCE_SYSTEM_RAM resource with
IORESOURCE_EXCLUSIVE, we will disallow any /dev/mem access to our device
region until the driver was unloaded cleanly and removed the parent
region.  This will work even though only some memory blocks are actually
currently added to Linux and appear as busy in the resource tree.

So access to the region from user space is only possible
a) if we don't load the virtio-mem driver.
b) after unloading the virtio-mem driver cleanly.

Don't build virtio-mem if access to /dev/mem cannot be restricticted -- if
we have CONFIG_DEVMEM=y but CONFIG_STRICT_DEVMEM is not set.

Link: https://lkml.kernel.org/r/20210920142856.17758-4-david@redhat.comSigned-off-by: NDavid Hildenbrand <david@redhat.com>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

virtio-mem dynamically exposes memory inside a device memory region as
system RAM to Linux, coordinating with the hypervisor which parts are
actually "plugged" and consequently usable/accessible.

On the one hand, the virtio-mem driver adds/removes whole memory blocks,
creating/removing busy IORESOURCE_SYSTEM_RAM resources, on the other
hand, it logically (un)plugs memory inside added memory blocks,
dynamically either exposing them to the buddy or hiding them from the
buddy and marking them PG_offline.

In contrast to physical devices, like a DIMM, the virtio-mem driver is
required to actually make use of any of the device-provided memory,
because it performs the handshake with the hypervisor.  virtio-mem
memory cannot simply be access via /dev/mem without a driver.

There is no safe way to:
a) Access plugged memory blocks via /dev/mem, as they might contain
   unplugged holes or might get silently unplugged by the virtio-mem
   driver and consequently turned inaccessible.
b) Access unplugged memory blocks via /dev/mem because the virtio-mem
   driver is required to make them actually accessible first.

The virtio-spec states that unplugged memory blocks MUST NOT be written,
and only selected unplugged memory blocks MAY be read.  We want to make
sure, this is the case in sane environments -- where the virtio-mem driver
was loaded.

We want to make sure that in a sane environment, nobody "accidentially"
accesses unplugged memory inside the device managed region.  For example,
a user might spot a memory region in /proc/iomem and try accessing it via
/dev/mem via gdb or dumping it via something else.  By the time the mmap()
happens, the memory might already have been removed by the virtio-mem
driver silently: the mmap() would succeeed and user space might
accidentially access unplugged memory.

So once the driver was loaded and detected the device along the
device-managed region, we just want to disallow any access via /dev/mem to
it.

In an ideal world, we would mark the whole region as busy ("owned by a
driver") and exclude it; however, that would be wrong, as we don't really
have actual system RAM at these ranges added to Linux ("busy system RAM").
Instead, we want to mark such ranges as "not actual busy system RAM but
still soft-reserved and prepared by a driver for future use."

Let's teach iomem_is_exclusive() to reject access to any range with
"IORESOURCE_SYSTEM_RAM | IORESOURCE_EXCLUSIVE", even if not busy and even
if "iomem=relaxed" is set.  Introduce EXCLUSIVE_SYSTEM_RAM to make it
easier for applicable drivers to depend on this setting in their Kconfig.

For now, there are no applicable ranges and we'll modify virtio-mem next
to properly set IORESOURCE_EXCLUSIVE on the parent resource container it
creates to contain all actual busy system RAM added via
add_memory_driver_managed().

Link: https://lkml.kernel.org/r/20210920142856.17758-3-david@redhat.comSigned-off-by: NDavid Hildenbrand <david@redhat.com>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "virtio-mem: disallow mapping virtio-mem memory via /dev/mem", v5.

Let's add the basic infrastructure to exclude some physical memory regions
marked as "IORESOURCE_SYSTEM_RAM" completely from /dev/mem access, even
though they are not marked IORESOURCE_BUSY and even though "iomem=relaxed"
is set.  Resource IORESOURCE_EXCLUSIVE for that purpose instead of adding
new flags to express something similar to "soft-busy" or "not busy yet,
but already prepared by a driver and not to be mapped by user space".

Use it for virtio-mem, to disallow mapping any virtio-mem memory via
/dev/mem to user space after the virtio-mem driver was loaded.

This patch (of 3):

We end up traversing subtrees of ranges we are not interested in; let's
optimize this case, skipping such subtrees, cleaning up the function a
bit.

For example, in the following configuration (/proc/iomem):

  00000000-00000fff : Reserved
  00001000-00057fff : System RAM
  00058000-00058fff : Reserved
  00059000-0009cfff : System RAM
  0009d000-000fffff : Reserved
     000a0000-000bffff : PCI Bus 0000:00
     000c0000-000c3fff : PCI Bus 0000:00
     000c4000-000c7fff : PCI Bus 0000:00
     000c8000-000cbfff : PCI Bus 0000:00
     000cc000-000cffff : PCI Bus 0000:00
     000d0000-000d3fff : PCI Bus 0000:00
     000d4000-000d7fff : PCI Bus 0000:00
     000d8000-000dbfff : PCI Bus 0000:00
     000dc000-000dffff : PCI Bus 0000:00
     000e0000-000e3fff : PCI Bus 0000:00
     000e4000-000e7fff : PCI Bus 0000:00
     000e8000-000ebfff : PCI Bus 0000:00
     000ec000-000effff : PCI Bus 0000:00
     000f0000-000fffff : PCI Bus 0000:00
       000f0000-000fffff : System ROM
  00100000-3fffffff : System RAM
  40000000-403fffff : Reserved
     40000000-403fffff : pnp 00:00
  40400000-80a79fff : System RAM
  ...

We don't have to look at any children of "0009d000-000fffff : Reserved"
if we can just skip these 15 items directly because the parent range is
not of interest.

Link: https://lkml.kernel.org/r/20210920142856.17758-1-david@redhat.com
Link: https://lkml.kernel.org/r/20210920142856.17758-2-david@redhat.comSigned-off-by: NDavid Hildenbrand <david@redhat.com>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is related to two previous changes.  Commit dfe4529e
("scripts/gdb: find vmlinux where it was before") and commit da036ae1
("scripts/gdb: handle split debug").

Although Chrome OS has been using the debug suffix for modules for a
while, it has just recently started using it for vmlinux as well.  That
means we've now got to improve the detection of "vmlinux" to also handle
that it might end with ".debug".

Link: https://lkml.kernel.org/r/20211028151120.v2.1.Ie6bd5a232f770acd8c9ffae487a02170bad3e963@changeidSigned-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NStephen Boyd <swboyd@chromium.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The kcov code mixes local_irq_save() and spin_lock() in
kcov_remote_{start|end}().  This creates a warning on PREEMPT_RT because
local_irq_save() disables interrupts and spin_lock_t is turned into a
sleeping lock which can not be acquired in a section with disabled
interrupts.

The kcov_remote_lock is used to synchronize the access to the hash-list
kcov_remote_map.  The local_irq_save() block protects access to the
per-CPU data kcov_percpu_data.

There is no compelling reason to change the lock type to raw_spin_lock_t
to make it work with local_irq_save().  Changing it would require to
move memory allocation (in kcov_remote_add()) and deallocation outside
of the locked section.

Adding an unlimited amount of entries to the hashlist will increase the
IRQ-off time during lookup.  It could be argued that this is debug code
and the latency does not matter.  There is however no need to do so and
it would allow to use this facility in an RT enabled build.

Using a local_lock_t instead of local_irq_save() has the befit of adding
a protection scope within the source which makes it obvious what is
protected.  On a !PREEMPT_RT && !LOCKDEP build the local_lock_irqsave()
maps directly to local_irq_save() so there is overhead at runtime.

Replace the local_irq_save() section with a local_lock_t.

Link: https://lkml.kernel.org/r/20210923164741.1859522-6-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-6-bigeasy@linutronix.deReported-by: NClark Williams <williams@redhat.com>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NDmitry Vyukov <dvyukov@google.com>
Acked-by: NMarco Elver <elver@google.com>
Tested-by: NMarco Elver <elver@google.com>
Reviewed-by: NAndrey Konovalov <andreyknvl@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kcov_remote_start() may need to allocate memory in the in_task() case
(otherwise per-CPU memory has been pre-allocated) and therefore requires
enabled interrupts.

The interrupts are enabled before checking if the allocation is required
so if no allocation is required then the interrupts are needlessly enabled
and disabled again.

Enable interrupts only if memory allocation is performed.

Link: https://lkml.kernel.org/r/20210923164741.1859522-5-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-5-bigeasy@linutronix.deSigned-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NDmitry Vyukov <dvyukov@google.com>
Acked-by: NMarco Elver <elver@google.com>
Tested-by: NMarco Elver <elver@google.com>
Reviewed-by: NAndrey Konovalov <andreyknvl@gmail.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

During boot kcov allocates per-CPU memory which is used later if remote/
softirq processing is enabled.

Allocate the per-CPU memory on the CPU local node to avoid cross node
memory access.

Link: https://lkml.kernel.org/r/20210923164741.1859522-4-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-4-bigeasy@linutronix.deSigned-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NDmitry Vyukov <dvyukov@google.com>
Acked-by: NMarco Elver <elver@google.com>
Tested-by: NMarco Elver <elver@google.com>
Reviewed-by: NAndrey Konovalov <andreyknvl@gmail.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The example code uses the variable `ip' but never declares it.

Declare `ip' as a 64bit variable which is the same type as the array
from which it loads its value.

Link: https://lkml.kernel.org/r/20210923164741.1859522-3-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-3-bigeasy@linutronix.deSigned-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NDmitry Vyukov <dvyukov@google.com>
Acked-by: NMarco Elver <elver@google.com>
Tested-by: NMarco Elver <elver@google.com>
Reviewed-by: NAndrey Konovalov <andreyknvl@gmail.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "kcov: PREEMPT_RT fixup + misc", v2.

The last patch in series is follow-up to address the PREEMPT_RT issue
within in kcov reported by Clark [1].  Patches 1-3 are smaller things that
I noticed while staring at it.  Patch 4 is small change which makes
replacement in #5 simpler / more obvious.

[1] https://lkml.kernel.org/r/20210809155909.333073de@theseus.lan

This patch (of 5):

The first example code has includes at the top, the following two
example share that part. The last example (remote coverage collection)
requires the linux/types.h header file due its __aligned_u64 usage.

Add the linux/types.h to the top most example and a comment that the
header files from above are required as it is done in the second
example.

Link: https://lkml.kernel.org/r/20210923164741.1859522-1-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-2-bigeasy@linutronix.de
Link: https://lkml.kernel.org/r/20210923164741.1859522-2-bigeasy@linutronix.deSigned-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NDmitry Vyukov <dvyukov@google.com>
Acked-by: NMarco Elver <elver@google.com>
Tested-by: NMarco Elver <elver@google.com>
Reviewed-by: NAndrey Konovalov <andreyknvl@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Clark Williams <williams@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There were runtime checks about sizes of struct v7_super_block and struct
sysv_inode.  If one of these checks fail the kernel will panic.  Since
these values are known at compile time let's use BUILD_BUG_ON(), because
it's a standard mechanism for validation checking at build time

Link: https://lkml.kernel.org/r/20210813123020.22971-1-paskripkin@gmail.com
Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: NPavel Skripkin <paskripkin@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use swap() instead of reimplementing it.

Link: https://lkml.kernel.org/r/20210909022046.8151-1-ran.xiaokai@zte.com.cnSigned-off-by: NRan Xiaokai <ran.xiaokai@zte.com.cn>
Cc: Gabriel Krisman Bertazi <krisman@collabora.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexey Gladkov <legion@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

DEFINE_PROC_SHOW_ATTRIBUTE() is supposed to be used to define a series
of functions and variables to register proc file easily. And the users
can use proc_create_data() to pass their own private data and get it
via seq->private in the callback. Unfortunately, the proc file system
use PDE_DATA() to get private data instead of inode->i_private. So fix
it. Fortunately, there only one user of it which does not pass any
private data, so this bug does not break any in-tree codes.

Link: https://lkml.kernel.org/r/20211029032638.84884-1-songmuchun@bytedance.com
Fixes: 97a32539 ("proc: convert everything to "struct proc_ops"")
Signed-off-by: NMuchun Song <songmuchun@bytedance.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Florent Revest <revest@chromium.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move seq_escape() to the header as inliner, for a small kernel text size
reduction.

Link: https://lkml.kernel.org/r/20211001122917.67228-1-andriy.shevchenko@linux.intel.comSigned-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

'linux/string.h' included in 'signal.h' is duplicated.
it's also included at line 7.

Link: https://lkml.kernel.org/r/20211019024934.973008-1-ye.guojin@zte.com.cnSigned-off-by: NYe Guojin <ye.guojin@zte.com.cn>
Reported-by: NZeal Robot <zealci@zte.com.cn>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In crash_dump.h, header file <linux/pgtable.h> is included twice.  This
duplication was introduced in commit 65fddcfc("mm: reorder includes
after introduction of linux/pgtable.h") where the order of the header
files is adjusted, while the old one was not removed.

Clean it up here.

Link: https://lkml.kernel.org/r/20211020090659.1038877-1-ye.guojin@zte.com.cnSigned-off-by: NYe Guojin <ye.guojin@zte.com.cn>
Reported-by: NZeal Robot <zealci@zte.com.cn>
Acked-by: NBaoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Changcheng Deng <deng.changcheng@zte.com.cn>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

./include/linux/crash_dump.h: 119: 50-51: WARNING: return of 0/1 in
function 'is_kdump_kernel' with return type bool

Return statements in functions returning bool should use true/false
instead of 1/0.

Link: https://lkml.kernel.org/r/20211020083905.1037952-1-deng.changcheng@zte.com.cnSigned-off-by: NChangcheng Deng <deng.changcheng@zte.com.cn>
Reported-by: NZeal Robot <zealci@zte.com.cn>
Reviewed-by: NSimon Horman <horms@kernel.org>
Acked-by: NBaoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Ye Guojin <ye.guojin@zte.com.cn>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

gcc warns about a couple of instances in which a sanity check exists but
the author wasn't sure how to react to it failing, which makes it look
like a possible bug:

  fs/hfsplus/inode.c: In function 'hfsplus_cat_read_inode':
  fs/hfsplus/inode.c:503:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
    503 |                         /* panic? */;
        |                                     ^
  fs/hfsplus/inode.c:524:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
    524 |                         /* panic? */;
        |                                     ^
  fs/hfsplus/inode.c: In function 'hfsplus_cat_write_inode':
  fs/hfsplus/inode.c:582:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
    582 |                         /* panic? */;
        |                                     ^
  fs/hfsplus/inode.c:608:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
    608 |                         /* panic? */;
        |                                     ^
  fs/hfs/inode.c: In function 'hfs_write_inode':
  fs/hfs/inode.c:464:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
    464 |                         /* panic? */;
        |                                     ^
  fs/hfs/inode.c:485:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
    485 |                         /* panic? */;
        |                                     ^

panic() is probably not the correct choice here, but a WARN_ON
seems appropriate and avoids the compile-time warning.

Link: https://lkml.kernel.org/r/20210927102149.1809384-1-arnd@kernel.org
Link: https://lore.kernel.org/all/20210322223249.2632268-1-arnd@kernel.org/Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NChristian Brauner <christian.brauner@ubuntu.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove filenames that are not particularly useful in file comments, and
suppress checkpatch warnings

  WARNING: It's generally not useful to have the filename in the file

Link: https://lkml.kernel.org/r/1635151862-11547-3-git-send-email-konishi.ryusuke@gmail.comSigned-off-by: NRyusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Qing Wang <wangqing@vivo.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "nilfs2 updates".

This patch (of 2):

coccicheck complains about the use of snprintf() in sysfs show functions.

Fix the coccicheck warning:

  WARNING: use scnprintf or sprintf.

Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Link: https://lkml.kernel.org/r/1635151862-11547-1-git-send-email-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/1634095759-4625-1-git-send-email-wangqing@vivo.com
Link: https://lkml.kernel.org/r/1635151862-11547-2-git-send-email-konishi.ryusuke@gmail.comSigned-off-by: NQing Wang <wangqing@vivo.com>
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>