<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/Documentation/admin-guide/blockdev, branch master</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2026-04-15T19:59:16+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-15T19:59:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=334fbe734e687404f346eba7d5d96ed2b44d35ab'/>
<id>334fbe734e687404f346eba7d5d96ed2b44d35ab</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op-&gt;mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb-&gt;mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op-&gt;mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb-&gt;mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-7.1/block-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux</title>
<updated>2026-04-13T22:51:31+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-13T22:51:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7fe6ac157b7e15c8976bd62ad7cb98e248884e83'/>
<id>7fe6ac157b7e15c8976bd62ad7cb98e248884e83</id>
<content type='text'>
Pull block updates from Jens Axboe:

 - Add shared memory zero-copy I/O support for ublk, bypassing per-I/O
   copies between kernel and userspace by matching registered buffer
   PFNs at I/O time. Includes selftests.

 - Refactor bio integrity to support filesystem initiated integrity
   operations and arbitrary buffer alignment.

 - Clean up bio allocation, splitting bio_alloc_bioset() into clear fast
   and slow paths. Add bio_await() and bio_submit_or_kill() helpers,
   unify synchronous bi_end_io callbacks.

 - Fix zone write plug refcount handling and plug removal races. Add
   support for serializing zone writes at QD=1 for rotational zoned
   devices, yielding significant throughput improvements.

 - Add SED-OPAL ioctls for Single User Mode management and a STACK_RESET
   command.

 - Add io_uring passthrough (uring_cmd) support to the BSG layer.

 - Replace pp_buf in partition scanning with struct seq_buf.

 - zloop improvements and cleanups.

 - drbd genl cleanup, switching to pre_doit/post_doit.

 - NVMe pull request via Keith:
      - Fabrics authentication updates
      - Enhanced block queue limits support
      - Workqueue usage updates
      - A new write zeroes device quirk
      - Tagset cleanup fix for loop device

 - MD pull requests via Yu Kuai:
      - Fix raid5 soft lockup in retry_aligned_read()
      - Fix raid10 deadlock with check operation and nowait requests
      - Fix raid1 overlapping writes on writemostly disks
      - Fix sysfs deadlock on array_state=clear
      - Proactive RAID-5 parity building with llbitmap, with
        write_zeroes_unmap optimization for initial sync
      - Fix llbitmap barrier ordering, rdev skipping, and bitmap_ops
        version mismatch fallback
      - Fix bcache use-after-free and uninitialized closure
      - Validate raid5 journal metadata payload size
      - Various cleanups

 - Various other fixes, improvements, and cleanups

* tag 'for-7.1/block-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (146 commits)
  ublk: fix tautological comparison warning in ublk_ctrl_reg_buf
  scsi: bsg: fix buffer overflow in scsi_bsg_uring_cmd()
  block: refactor blkdev_zone_mgmt_ioctl
  MAINTAINERS: update ublk driver maintainer email
  Documentation: ublk: address review comments for SHMEM_ZC docs
  ublk: allow buffer registration before device is started
  ublk: replace xarray with IDA for shmem buffer index allocation
  ublk: simplify PFN range loop in __ublk_ctrl_reg_buf
  ublk: verify all pages in multi-page bvec fall within registered range
  ublk: widen ublk_shmem_buf_reg.len to __u64 for 4GB buffer support
  xfs: use bio_await in xfs_zone_gc_reset_sync
  block: add a bio_submit_or_kill helper
  block: factor out a bio_await helper
  block: unify the synchronous bi_end_io callbacks
  xfs: fix number of GC bvecs
  selftests/ublk: add read-only buffer registration test
  selftests/ublk: add filesystem fio verify test for shmem_zc
  selftests/ublk: add hugetlbfs shmem_zc test for loop target
  selftests/ublk: add shared memory zero-copy test
  selftests/ublk: add UBLK_F_SHMEM_ZC support for loop target
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull block updates from Jens Axboe:

 - Add shared memory zero-copy I/O support for ublk, bypassing per-I/O
   copies between kernel and userspace by matching registered buffer
   PFNs at I/O time. Includes selftests.

 - Refactor bio integrity to support filesystem initiated integrity
   operations and arbitrary buffer alignment.

 - Clean up bio allocation, splitting bio_alloc_bioset() into clear fast
   and slow paths. Add bio_await() and bio_submit_or_kill() helpers,
   unify synchronous bi_end_io callbacks.

 - Fix zone write plug refcount handling and plug removal races. Add
   support for serializing zone writes at QD=1 for rotational zoned
   devices, yielding significant throughput improvements.

 - Add SED-OPAL ioctls for Single User Mode management and a STACK_RESET
   command.

 - Add io_uring passthrough (uring_cmd) support to the BSG layer.

 - Replace pp_buf in partition scanning with struct seq_buf.

 - zloop improvements and cleanups.

 - drbd genl cleanup, switching to pre_doit/post_doit.

 - NVMe pull request via Keith:
      - Fabrics authentication updates
      - Enhanced block queue limits support
      - Workqueue usage updates
      - A new write zeroes device quirk
      - Tagset cleanup fix for loop device

 - MD pull requests via Yu Kuai:
      - Fix raid5 soft lockup in retry_aligned_read()
      - Fix raid10 deadlock with check operation and nowait requests
      - Fix raid1 overlapping writes on writemostly disks
      - Fix sysfs deadlock on array_state=clear
      - Proactive RAID-5 parity building with llbitmap, with
        write_zeroes_unmap optimization for initial sync
      - Fix llbitmap barrier ordering, rdev skipping, and bitmap_ops
        version mismatch fallback
      - Fix bcache use-after-free and uninitialized closure
      - Validate raid5 journal metadata payload size
      - Various cleanups

 - Various other fixes, improvements, and cleanups

* tag 'for-7.1/block-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (146 commits)
  ublk: fix tautological comparison warning in ublk_ctrl_reg_buf
  scsi: bsg: fix buffer overflow in scsi_bsg_uring_cmd()
  block: refactor blkdev_zone_mgmt_ioctl
  MAINTAINERS: update ublk driver maintainer email
  Documentation: ublk: address review comments for SHMEM_ZC docs
  ublk: allow buffer registration before device is started
  ublk: replace xarray with IDA for shmem buffer index allocation
  ublk: simplify PFN range loop in __ublk_ctrl_reg_buf
  ublk: verify all pages in multi-page bvec fall within registered range
  ublk: widen ublk_shmem_buf_reg.len to __u64 for 4GB buffer support
  xfs: use bio_await in xfs_zone_gc_reset_sync
  block: add a bio_submit_or_kill helper
  block: factor out a bio_await helper
  block: unify the synchronous bi_end_io callbacks
  xfs: fix number of GC bvecs
  selftests/ublk: add read-only buffer registration test
  selftests/ublk: add filesystem fio verify test for shmem_zc
  selftests/ublk: add hugetlbfs shmem_zc test for loop target
  selftests/ublk: add shared memory zero-copy test
  selftests/ublk: add UBLK_F_SHMEM_ZC support for loop target
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: remove chained recompression</title>
<updated>2026-04-05T20:53:24+00:00</updated>
<author>
<name>Sergey Senozhatsky</name>
<email>senozhatsky@chromium.org</email>
</author>
<published>2026-03-11T08:42:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=cedfa028b54e584532026888dec94039b62b3d1f'/>
<id>cedfa028b54e584532026888dec94039b62b3d1f</id>
<content type='text'>
Chained recompression has unpredictable behavior and is not useful in
practice.

First, systems usually configure just one alternative recompression
algorithm, which has slower compression/decompression but better
compression ratio.  A single alternative algorithm doesn't need chaining.

Second, even with multiple recompression algorithms, chained recompression
is suboptimal.  If a lower priority algorithm succeeds, the page is never
attempted with a higher priority algorithm, leading to worse memory
savings.  If a lower priority algorithm fails, the page is still attempted
with a higher priority algorithm, wasting resources on the failed lower
priority attempt.

In either case, the system would be better off targeting a specific
priority directly.

Chained recompression also significantly complicates the code.  Remove it.

Link: https://lkml.kernel.org/r/20260311084312.1766036-6-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: gao xu &lt;gaoxu2@honor.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Chained recompression has unpredictable behavior and is not useful in
practice.

First, systems usually configure just one alternative recompression
algorithm, which has slower compression/decompression but better
compression ratio.  A single alternative algorithm doesn't need chaining.

Second, even with multiple recompression algorithms, chained recompression
is suboptimal.  If a lower priority algorithm succeeds, the page is never
attempted with a higher priority algorithm, leading to worse memory
savings.  If a lower priority algorithm fails, the page is still attempted
with a higher priority algorithm, wasting resources on the failed lower
priority attempt.

In either case, the system would be better off targeting a specific
priority directly.

Chained recompression also significantly complicates the code.  Remove it.

Link: https://lkml.kernel.org/r/20260311084312.1766036-6-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: gao xu &lt;gaoxu2@honor.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: update recompression documentation</title>
<updated>2026-04-05T20:53:24+00:00</updated>
<author>
<name>Sergey Senozhatsky</name>
<email>senozhatsky@chromium.org</email>
</author>
<published>2026-03-11T08:42:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=be5f13d94846e8207c9aac0180b13ce1f762e1b1'/>
<id>be5f13d94846e8207c9aac0180b13ce1f762e1b1</id>
<content type='text'>
Emphasize usage of the `priority` parameter for recompression and explain
why `algo` parameter can lead to unexpected behavior and thus is not
recommended.

Link: https://lkml.kernel.org/r/20260311084312.1766036-5-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: gao xu &lt;gaoxu2@honor.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Emphasize usage of the `priority` parameter for recompression and explain
why `algo` parameter can lead to unexpected behavior and thus is not
recommended.

Link: https://lkml.kernel.org/r/20260311084312.1766036-5-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: gao xu &lt;gaoxu2@honor.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zloop: add max_open_zones option</title>
<updated>2026-03-31T14:33:28+00:00</updated>
<author>
<name>Damien Le Moal</name>
<email>dlemoal@kernel.org</email>
</author>
<published>2026-03-26T20:32:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b2a78fec344ead9ffca63ee13018f482392bf09d'/>
<id>b2a78fec344ead9ffca63ee13018f482392bf09d</id>
<content type='text'>
Introduce the new max_open_zones option to allow specifying a limit on
the maximum number of open zones of a zloop device. This change allows
creating a zloop device that can more closely mimick the characteristics
of a physical SMR drive.

When set to a non zero value, only up to max_open_zones zones can be in
the implicit open (BLK_ZONE_COND_IMP_OPEN) and explicit open
(BLK_ZONE_COND_EXP_OPEN) conditions at any time. The transition to the
implicit open condition of a zone on a write operation can result in an
implicit close of an already implicitly open zone. This is handled in
the function zloop_do_open_zone(). This function also handles
transitions to the explicit open condition. Implicit close transitions
are handled using an LRU ordered list of open zones which is managed
using the helper functions zloop_lru_rotate_open_zone() and
zloop_lru_remove_open_zone().

Signed-off-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://patch.msgid.link/20260326203245.946830-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Introduce the new max_open_zones option to allow specifying a limit on
the maximum number of open zones of a zloop device. This change allows
creating a zloop device that can more closely mimick the characteristics
of a physical SMR drive.

When set to a non zero value, only up to max_open_zones zones can be in
the implicit open (BLK_ZONE_COND_IMP_OPEN) and explicit open
(BLK_ZONE_COND_EXP_OPEN) conditions at any time. The transition to the
implicit open condition of a zone on a write operation can result in an
implicit close of an already implicitly open zone. This is handled in
the function zloop_do_open_zone(). This function also handles
transitions to the explicit open condition. Implicit close transitions
are handled using an LRU ordered list of open zones which is managed
using the helper functions zloop_lru_rotate_open_zone() and
zloop_lru_remove_open_zone().

Signed-off-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://patch.msgid.link/20260326203245.946830-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zloop: forget write cache on force removal</title>
<updated>2026-03-25T12:49:01+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2026-03-23T07:11:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=829def1e35ca3a6ef07d53d47089ef7cff0fd127'/>
<id>829def1e35ca3a6ef07d53d47089ef7cff0fd127</id>
<content type='text'>
Add a new options that causes zloop to truncate the zone files to the
write pointer value recorded at the last cache flush to simulate
unclean shutdowns.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Bart Van Assche &lt;bvanassche@acm.org&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Link: https://patch.msgid.link/20260323071156.2940772-3-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add a new options that causes zloop to truncate the zone files to the
write pointer value recorded at the last cache flush to simulate
unclean shutdowns.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Bart Van Assche &lt;bvanassche@acm.org&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Link: https://patch.msgid.link/20260323071156.2940772-3-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: rename writeback_compressed device attr</title>
<updated>2026-03-04T17:44:23+00:00</updated>
<author>
<name>Sergey Senozhatsky</name>
<email>senozhatsky@chromium.org</email>
</author>
<published>2026-02-26T02:54:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ba4c3698e6963eacd8e7c86c13343631bfeabe55'/>
<id>ba4c3698e6963eacd8e7c86c13343631bfeabe55</id>
<content type='text'>
Rename writeback_compressed attr to compressed_writeback to avoid possible
confusion and have more natural naming.  writeback_compressed may look
like an alternative version of writeback while in fact
writeback_compressed only sets a writeback property.  Make this
distinction more clear with a new compressed_writeback name.

This updates a feature which is new in 7.0-rcX.

Link: https://lkml.kernel.org/r/20260226025429.1042083-1-senozhatsky@chromium.org
Fixes: 4c1d61389e8e ("zram: introduce writeback_compressed device attribute")
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Suggested-by: Minchan Kim &lt;minchan@kernel.org&gt;
Acked-by: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: Richard Chang &lt;richardycc@google.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: "Christoph Böhmwalder" &lt;christoph.boehmwalder@linbit.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Lars Ellenberg &lt;lars.ellenberg@linbit.com&gt;
Cc: Philipp Reisner &lt;philipp.reisner@linbit.com&gt;
Cc: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Rename writeback_compressed attr to compressed_writeback to avoid possible
confusion and have more natural naming.  writeback_compressed may look
like an alternative version of writeback while in fact
writeback_compressed only sets a writeback property.  Make this
distinction more clear with a new compressed_writeback name.

This updates a feature which is new in 7.0-rcX.

Link: https://lkml.kernel.org/r/20260226025429.1042083-1-senozhatsky@chromium.org
Fixes: 4c1d61389e8e ("zram: introduce writeback_compressed device attribute")
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Suggested-by: Minchan Kim &lt;minchan@kernel.org&gt;
Acked-by: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: Richard Chang &lt;richardycc@google.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: "Christoph Böhmwalder" &lt;christoph.boehmwalder@linbit.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Lars Ellenberg &lt;lars.ellenberg@linbit.com&gt;
Cc: Philipp Reisner &lt;philipp.reisner@linbit.com&gt;
Cc: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: document writeback_batch_size</title>
<updated>2026-01-21T03:24:36+00:00</updated>
<author>
<name>Sergey Senozhatsky</name>
<email>senozhatsky@chromium.org</email>
</author>
<published>2025-12-01T09:47:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2502673aed6c66befc7efc2dc008e2a8a50508cd'/>
<id>2502673aed6c66befc7efc2dc008e2a8a50508cd</id>
<content type='text'>
Add missing writeback_batch_size documentation.

Link: https://lkml.kernel.org/r/20251201094754.4149975-4-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: David Stevens &lt;stevensd@google.com&gt;
Cc: Minchan Kim &lt;minchan@google.com&gt;
Cc: Richard Chang &lt;richardycc@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add missing writeback_batch_size documentation.

Link: https://lkml.kernel.org/r/20251201094754.4149975-4-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: David Stevens &lt;stevensd@google.com&gt;
Cc: Minchan Kim &lt;minchan@google.com&gt;
Cc: Richard Chang &lt;richardycc@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>zram: introduce writeback_compressed device attribute</title>
<updated>2026-01-21T03:24:36+00:00</updated>
<author>
<name>Richard Chang</name>
<email>richardycc@google.com</email>
</author>
<published>2025-12-01T09:47:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4c1d61389e8e4307449eb2ebad997241cbf08fef'/>
<id>4c1d61389e8e4307449eb2ebad997241cbf08fef</id>
<content type='text'>
Introduce witeback_compressed device attribute to toggle compressed
writeback (decompression on demand) feature.

[senozhatsky@chromium.org: rewrote original patch, added documentation]
Link: https://lkml.kernel.org/r/20251201094754.4149975-3-senozhatsky@chromium.org
Signed-off-by: Richard Chang &lt;richardycc@google.com&gt;
Co-developed-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: David Stevens &lt;stevensd@google.com&gt;
Cc: Minchan Kim &lt;minchan@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Introduce witeback_compressed device attribute to toggle compressed
writeback (decompression on demand) feature.

[senozhatsky@chromium.org: rewrote original patch, added documentation]
Link: https://lkml.kernel.org/r/20251201094754.4149975-3-senozhatsky@chromium.org
Signed-off-by: Richard Chang &lt;richardycc@google.com&gt;
Co-developed-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Signed-off-by: Sergey Senozhatsky &lt;senozhatsky@chromium.org&gt;
Cc: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: David Stevens &lt;stevensd@google.com&gt;
Cc: Minchan Kim &lt;minchan@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Documentation: admin-guide: blockdev: replace zone_capacity with zone_capacity_mb when creating devices</title>
<updated>2025-12-15T16:56:06+00:00</updated>
<author>
<name>Yongpeng Yang</name>
<email>yangyongpeng@xiaomi.com</email>
</author>
<published>2025-12-15T09:58:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=67d85b062dcb49af9c903a58842a4ed7281f57b8'/>
<id>67d85b062dcb49af9c903a58842a4ed7281f57b8</id>
<content type='text'>
The "zone_capacity=%umb" option is no longer used. The effective option
is now "zone_capacity_mb=%u", so update the documentation accordingly.

Signed-off-by: Yongpeng Yang &lt;yangyongpeng@xiaomi.com&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The "zone_capacity=%umb" option is no longer used. The effective option
is now "zone_capacity_mb=%u", so update the documentation accordingly.

Signed-off-by: Yongpeng Yang &lt;yangyongpeng@xiaomi.com&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
</feed>
