Setting backing device is done before ZRAM initialization.  If we set the
backing device, then remove the ZRAM module without initializing the
device, the backing device reference will be leaked and the device will be
hold forever.

Fix this by always reset the ZRAM fully on rmmod or reset store.

Link: https://lkml.kernel.org/r/20241209165717.94215-3-ryncsn@gmail.com
Fixes: 013bf95a83ec ("zram: add interface to specif backing device")
Signed-off-by: Kairui Song <kasong@tencent.com>
Reported-by: Desheng Wu <deshengwu@tencent.com>
Suggested-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Patch series "zram: fix backing device setup issue", v2.

This series fixes two bugs of backing device setting:

- ZRAM should reject using a zero sized (or the uninitialized ZRAM
  device itself) as the backing device.
- Fix backing device leaking when removing a uninitialized ZRAM
  device.


This patch (of 2):

Setting a zero sized block device as backing device is pointless, and one
can easily create a recursive loop by setting the uninitialized ZRAM
device itself as its own backing device by (zram0 is uninitialized):

    echo /dev/zram0 > /sys/block/zram0/backing_dev

It's definitely a wrong config, and the module will pin itself, kernel
should refuse doing so in the first place.

By refusing to use zero sized device we avoided misuse cases including
this one above.

Link: https://lkml.kernel.org/r/20241209165717.94215-1-ryncsn@gmail.com
Link: https://lkml.kernel.org/r/20241209165717.94215-2-ryncsn@gmail.com
Fixes: 013bf95a83ec ("zram: add interface to specif backing device")
Signed-off-by: Kairui Song <kasong@tencent.com>
Reported-by: Desheng Wu <deshengwu@tencent.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Commit 4ce6e2db00de ("virtio-blk: Ensure no requests in virtqueues before
deleting vqs.") replaces queue quiesce with queue freeze in virtio-blk's
PM callbacks. And the motivation is to drain inflight IOs before suspending.

block layer's queue freeze looks very handy, but it is also easy to cause
deadlock, such as, any attempt to call into bio_queue_enter() may run into
deadlock if the queue is frozen in current context. There are all kinds
of ->suspend() called in suspend context, so keeping queue frozen in the
whole suspend context isn't one good idea. And Marek reported lockdep
warning[1] caused by virtio-blk's freeze queue in virtblk_freeze().

[1] https://lore.kernel.org/linux-block/ca16370e-d646-4eee-b9cc-87277c89c43c@samsung.com/

Given the motivation is to drain in-flight IOs, it can be done by calling
freeze & unfreeze, meantime restore to previous behavior by keeping queue
quiesced during suspend.

Cc: Yi Sun <yi.sun@unisoc.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: virtualization@lists.linux.dev
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://lore.kernel.org/r/20241112125821.1475793-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Add the missing description to fix the following warning:

WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/block/rnull_mod.o

Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20241130094521.193924-1-fujita.tomonori@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The continual trickle of small conversion patches is grating on me, and
is really not helping.  Just get rid of the 'remove_new' member
function, which is just an alias for the plain 'remove', and had a
comment to that effect:

  /*
   * .remove_new() is a relic from a prototype conversion of .remove().
   * New drivers are supposed to implement .remove(). Once all drivers are
   * converted to not use .remove_new any more, it will be dropped.
   */

This was just a tree-wide 'sed' script that replaced '.remove_new' with
'.remove', with some care taken to turn a subsequent tab into two tabs
to make things line up.

I did do some minimal manual whitespace adjustment for places that used
spaces to line things up.

Then I just removed the old (sic) .remove_new member function, and this
is the end result.  No more unnecessary conversion noise.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull more block updates from Jens Axboe:

 - NVMe pull request via Keith:
      - Use correct srcu list traversal (Breno)
      - Scatter-gather support for metadata (Keith)
      - Fabrics shutdown race condition fix (Nilay)
      - Persistent reservations updates (Guixin)

 - Add the required bits for MD atomic write support for raid0/1/10

 - Correct return value for unknown opcode in ublk

 - Fix deadlock with zone revalidation

 - Fix for the io priority request vs bio cleanups

 - Use the correct unsigned int type for various limit helpers

 - Fix for a race in loop

 - Cleanup blk_rq_prep_clone() to prevent uninit-value warning and make
   it easier for actual humans to read

 - Fix potential UAF when iterating tags

 - A few fixes for bfq-iosched UAF issues

 - Fix for brd discard not decrementing the allocated page count

 - Various little fixes and cleanups

* tag 'block-6.13-20242901' of git://git.kernel.dk/linux: (36 commits)
  brd: decrease the number of allocated pages which discarded
  block, bfq: fix bfqq uaf in bfq_limit_depth()
  block: Don't allow an atomic write be truncated in blkdev_write_iter()
  mq-deadline: don't call req_get_ioprio from the I/O completion handler
  block: Prevent potential deadlock in blk_revalidate_disk_zones()
  block: Remove extra part pointer NULLify in blk_rq_init()
  nvme: tuning pr code by using defined structs and macros
  nvme: introduce change ptpl and iekey definition
  block: return bool from get_disk_ro and bdev_read_only
  block: remove a duplicate definition for bdev_read_only
  block: return bool from blk_rq_aligned
  block: return unsigned int from blk_lim_dma_alignment_and_pad
  block: return unsigned int from queue_dma_alignment
  block: return unsigned int from bdev_io_opt
  block: req->bio is always set in the merge code
  block: don't bother checking the data direction for merges
  block: blk-mq: fix uninit-value in blk_rq_prep_clone and refactor
  Revert "block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator()"
  md/raid10: Atomic write support
  md/raid1: Atomic write support
  ...

The number of allocated pages which discarded will not decrease.
Fix it.

Fixes: 9ead7efc6f3f ("brd: implement discard support")

Signed-off-by: Zhang Xianwei <zhang.xianwei8@zte.com.cn>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241128170056565nPKSz2vsP8K8X2uk2iaDG@zte.com.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Enable a series of lints, including safety-related ones, e.g. the
     compiler will now warn about missing safety comments, as well as
     unnecessary ones. How safety documentation is organized is a
     frequent source of review comments, thus having the compiler guide
     new developers on where they are expected (and where not) is very
     nice.

   - Start using '#[expect]': an interesting feature in Rust (stabilized
     in 1.81.0) that makes the compiler warn if an expected warning was
     _not_ emitted. This is useful to avoid forgetting cleaning up
     locally ignored diagnostics ('#[allow]'s).

   - Introduce '.clippy.toml' configuration file for Clippy, the Rust
     linter, which will allow us to tweak its behaviour. For instance,
     our first use cases are declaring a disallowed macro and, more
     importantly, enabling the checking of private items.

   - Lints-related fixes and cleanups related to the items above.

   - Migrate from 'receiver_trait' to 'arbitrary_self_types': to get the
     kernel into stable Rust, one of the major pieces of the puzzle is
     the support to write custom types that can be used as 'self', i.e.
     as receivers, since the kernel needs to write types such as 'Arc'
     that common userspace Rust would not. 'arbitrary_self_types' has
     been accepted to become stable, and this is one of the steps
     required to get there.

   - Remove usage of the 'new_uninit' unstable feature.

   - Use custom C FFI types. Includes a new 'ffi' crate to contain our
     custom mapping, instead of using the standard library 'core::ffi'
     one. The actual remapping will be introduced in a later cycle.

   - Map '__kernel_{size_t,ssize_t,ptrdiff_t}' to 'usize'/'isize'
     instead of 32/64-bit integers.

   - Fix 'size_t' in bindgen generated prototypes of C builtins.

   - Warn on bindgen < 0.69.5 and libclang >= 19.1 due to a double issue
     in the projects, which we managed to trigger with the upcoming
     tracepoint support. It includes a build test since some
     distributions backported the fix (e.g. Debian -- thanks!). All
     major distributions we list should be now OK except Ubuntu non-LTS.

  'macros' crate:

   - Adapt the build system to be able run the doctests there too; and
     clean up and enable the corresponding doctests.

  'kernel' crate:

   - Add 'alloc' module with generic kernel allocator support and remove
     the dependency on the Rust standard library 'alloc' and the
     extension traits we used to provide fallible methods with flags.

     Add the 'Allocator' trait and its implementations '{K,V,KV}malloc'.
     Add the 'Box' type (a heap allocation for a single value of type
     'T' that is also generic over an allocator and considers the
     kernel's GFP flags) and its shorthand aliases '{K,V,KV}Box'. Add
     'ArrayLayout' type. Add 'Vec' (a contiguous growable array type)
     and its shorthand aliases '{K,V,KV}Vec', including iterator
     support.

     For instance, now we may write code such as:

         let mut v = KVec::new();
         v.push(1, GFP_KERNEL)?;
         assert_eq!(&v, &[1]);

     Treewide, move as well old users to these new types.

   - 'sync' module: add global lock support, including the
     'GlobalLockBackend' trait; the 'Global{Lock,Guard,LockedBy}' types
     and the 'global_lock!' macro. Add the 'Lock::try_lock' method.

   - 'error' module: optimize 'Error' type to use 'NonZeroI32' and make
     conversion functions public.

   - 'page' module: add 'page_align' function.

   - Add 'transmute' module with the existing 'FromBytes' and 'AsBytes'
     traits.

   - 'block::mq::request' module: improve rendered documentation.

   - 'types' module: extend 'Opaque' type documentation and add simple
     examples for the 'Either' types.

  drm/panic:

   - Clean up a series of Clippy warnings.

  Documentation:

   - Add coding guidelines for lints and the '#[expect]' feature.

   - Add Ubuntu to the list of distributions in the Quick Start guide.

  MAINTAINERS:

   - Add Danilo Krummrich as maintainer of the new 'alloc' module.

  And a few other small cleanups and fixes"

* tag 'rust-6.13' of https://github.com/Rust-for-Linux/linux: (82 commits)
  rust: alloc: Fix `ArrayLayout` allocations
  docs: rust: remove spurious item in `expect` list
  rust: allow `clippy::needless_lifetimes`
  rust: warn on bindgen < 0.69.5 and libclang >= 19.1
  rust: use custom FFI integer types
  rust: map `__kernel_size_t` and friends also to usize/isize
  rust: fix size_t in bindgen prototypes of C builtins
  rust: sync: add global lock support
  rust: macros: enable the rest of the tests
  rust: macros: enable paste! use from macro_rules!
  rust: enable macros::module! tests
  rust: kbuild: expand rusttest target for macros
  rust: types: extend `Opaque` documentation
  rust: block: fix formatting of `kernel::block::mq::request` module
  rust: macros: fix documentation of the paste! macro
  rust: kernel: fix THIS_MODULE header path in ThisModule doc comment
  rust: page: add Rust version of PAGE_ALIGN
  rust: helpers: remove unnecessary header includes
  rust: exports: improve grammar in commentary
  drm/panic: allow verbose version check
  ...

Pull MM updates from Andrew Morton:

 - The series "zram: optimal post-processing target selection" from
   Sergey Senozhatsky improves zram's post-processing selection
   algorithm. This leads to improved memory savings.

 - Wei Yang has gone to town on the mapletree code, contributing several
   series which clean up the implementation:
	- "refine mas_mab_cp()"
	- "Reduce the space to be cleared for maple_big_node"
	- "maple_tree: simplify mas_push_node()"
	- "Following cleanup after introduce mas_wr_store_type()"
	- "refine storing null"

 - The series "selftests/mm: hugetlb_fault_after_madv improvements" from
   David Hildenbrand fixes this selftest for s390.

 - The series "introduce pte_offset_map_{ro|rw}_nolock()" from Qi Zheng
   implements some rationaizations and cleanups in the page mapping
   code.

 - The series "mm: optimize shadow entries removal" from Shakeel Butt
   optimizes the file truncation code by speeding up the handling of
   shadow entries.

 - The series "Remove PageKsm()" from Matthew Wilcox completes the
   migration of this flag over to being a folio-based flag.

 - The series "Unify hugetlb into arch_get_unmapped_area functions" from
   Oscar Salvador implements a bunch of consolidations and cleanups in
   the hugetlb code.

 - The series "Do not shatter hugezeropage on wp-fault" from Dev Jain
   takes away the wp-fault time practice of turning a huge zero page
   into small pages. Instead we replace the whole thing with a THP. More
   consistent cleaner and potentiall saves a large number of pagefaults.

 - The series "percpu: Add a test case and fix for clang" from Andy
   Shevchenko enhances and fixes the kernel's built in percpu test code.

 - The series "mm/mremap: Remove extra vma tree walk" from Liam Howlett
   optimizes mremap() by avoiding doing things which we didn't need to
   do.

 - The series "Improve the tmpfs large folio read performance" from
   Baolin Wang teaches tmpfs to copy data into userspace at the folio
   size rather than as individual pages. A 20% speedup was observed.

 - The series "mm/damon/vaddr: Fix issue in
   damon_va_evenly_split_region()" fro Zheng Yejian fixes DAMON
   splitting.

 - The series "memcg-v1: fully deprecate charge moving" from Shakeel
   Butt removes the long-deprecated memcgv2 charge moving feature.

 - The series "fix error handling in mmap_region() and refactor" from
   Lorenzo Stoakes cleanup up some of the mmap() error handling and
   addresses some potential performance issues.

 - The series "x86/module: use large ROX pages for text allocations"
   from Mike Rapoport teaches x86 to use large pages for
   read-only-execute module text.

 - The series "page allocation tag compression" from Suren Baghdasaryan
   is followon maintenance work for the new page allocation profiling
   feature.

 - The series "page->index removals in mm" from Matthew Wilcox remove
   most references to page->index in mm/. A slow march towards shrinking
   struct page.

 - The series "damon/{self,kunit}tests: minor fixups for DAMON debugfs
   interface tests" from Andrew Paniakin performs maintenance work for
   DAMON's self testing code.

 - The series "mm: zswap swap-out of large folios" from Kanchana Sridhar
   improves zswap's batching of compression and decompression. It is a
   step along the way towards using Intel IAA hardware acceleration for
   this zswap operation.

 - The series "kasan: migrate the last module test to kunit" from
   Sabyrzhan Tasbolatov completes the migration of the KASAN built-in
   tests over to the KUnit framework.

 - The series "implement lightweight guard pages" from Lorenzo Stoakes
   permits userapace to place fault-generating guard pages within a
   single VMA, rather than requiring that multiple VMAs be created for
   this. Improved efficiencies for userspace memory allocators are
   expected.

 - The series "memcg: tracepoint for flushing stats" from JP Kobryn uses
   tracepoints to provide increased visibility into memcg stats flushing
   activity.

 - The series "zram: IDLE flag handling fixes" from Sergey Senozhatsky
   fixes a zram buglet which potentially affected performance.

 - The series "mm: add more kernel parameters to control mTHP" from
   Maíra Canal enhances our ability to control/configuremultisize THP
   from the kernel boot command line.

 - The series "kasan: few improvements on kunit tests" from Sabyrzhan
   Tasbolatov has a couple of fixups for the KASAN KUnit tests.

 - The series "mm/list_lru: Split list_lru lock into per-cgroup scope"
   from Kairui Song optimizes list_lru memory utilization when lockdep
   is enabled.

* tag 'mm-stable-2024-11-18-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (215 commits)
  cma: enforce non-zero pageblock_order during cma_init_reserved_mem()
  mm/kfence: add a new kunit test test_use_after_free_read_nofault()
  zram: fix NULL pointer in comp_algorithm_show()
  memcg/hugetlb: add hugeTLB counters to memcg
  vmstat: call fold_vm_zone_numa_events() before show per zone NUMA event
  mm: mmap_lock: check trace_mmap_lock_$type_enabled() instead of regcount
  zram: ZRAM_DEF_COMP should depend on ZRAM
  MAINTAINERS/MEMORY MANAGEMENT: add document files for mm
  Docs/mm/damon: recommend academic papers to read and/or cite
  mm: define general function pXd_init()
  kmemleak: iommu/iova: fix transient kmemleak false positive
  mm/list_lru: simplify the list_lru walk callback function
  mm/list_lru: split the lock to per-cgroup scope
  mm/list_lru: simplify reparenting and initial allocation
  mm/list_lru: code clean up for reparenting
  mm/list_lru: don't export list_lru_add
  mm/list_lru: don't pass unnecessary key parameters
  kasan: add kunit tests for kmalloc_track_caller, kmalloc_node_track_caller
  kasan: change kasan_atomics kunit test as KUNIT_CASE_SLOW
  kasan: use EXPORT_SYMBOL_IF_KUNIT to export symbols
  ...

Pull reiserfs removal from Jan Kara:
 "The deprecation period of reiserfs is ending at the end of this year
  so it is time to remove it"

* tag 'reiserfs_delete' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  reiserfs: The last commit