<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/mm, branch v6.18.34</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.18.34</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.18.34'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2026-06-01T15:51:03+00:00</updated>
<entry>
<title>cgroup/rstat: validate cpu before css_rstat_cpu() access</title>
<updated>2026-06-01T15:51:03+00:00</updated>
<author>
<name>Qing Ming</name>
<email>a0yami@mailbox.org</email>
</author>
<published>2026-05-16T07:08:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=6a01413a4e8fcb0263d7bef5075c5f8f4eb3a8b6'/>
<id>urn:sha1:6a01413a4e8fcb0263d7bef5075c5f8f4eb3a8b6</id>
<content type='text'>
[ Upstream commit 8817005efbdfdf5d4e4814cb5dc52b53d12917d7 ]

css_rstat_updated() is exposed as a BPF kfunc and accepts a
caller-provided cpu argument. The function uses cpu for per-cpu rstat
lookups without checking whether it refers to a valid possible CPU.

A BPF iter/cgroup program with CAP_BPF and CAP_PERFMON can pass an
invalid cpu value. On an unfixed UBSCAN_BOUNDS test kernel, cpu ==
0x7fffffff triggers:

  UBSAN: array-index-out-of-bounds in kernel/cgroup/rstat.c:31:9
  index 2147483647 is out of range for type 'long unsigned int [64]'
  Call Trace:
    css_rstat_updated
    bpf_iter_run_prog
    cgroup_iter_seq_show
    bpf_seq_read

Add cpu validation to the BPF-facing css_rstat_updated() kfunc and
move the common implementation to __css_rstat_updated() for in-kernel
callers.

Fixes: a319185be9f5 ("cgroup: bpf: enable bpf programs to integrate with rstat")
Signed-off-by: Qing Ming &lt;a0yami@mailbox.org&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>mm/page_alloc: fix initialization of tags of the huge zero folio with init_on_free</title>
<updated>2026-06-01T15:50:41+00:00</updated>
<author>
<name>David Hildenbrand (Arm)</name>
<email>david@kernel.org</email>
</author>
<published>2026-04-21T15:39:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=738d18f1da3513d17b6f7bf30146cc4ac2480ffd'/>
<id>urn:sha1:738d18f1da3513d17b6f7bf30146cc4ac2480ffd</id>
<content type='text'>
commit 6a288a4ddb4a994490505ab5f41c445f8e6b6467 upstream.

__GFP_ZEROTAGS semantics are currently a bit weird, but effectively this
flag is only ever set alongside __GFP_ZERO and __GFP_SKIP_KASAN.

If we run with init_on_free, we will zero out pages during
__free_pages_prepare(), to skip zeroing on the allocation path.

However, when allocating with __GFP_ZEROTAG set, post_alloc_hook() will
consequently not only skip clearing page content, but also skip clearing
tag memory.

Not clearing tags through __GFP_ZEROTAGS is irrelevant for most pages that
will get mapped to user space through set_pte_at() later: set_pte_at() and
friends will detect that the tags have not been initialized yet
(PG_mte_tagged not set), and initialize them.

However, for the huge zero folio, which will be mapped through a PMD
marked as special, this initialization will not be performed, ending up
exposing whatever tags were still set for the pages.

The docs (Documentation/arch/arm64/memory-tagging-extension.rst) state
that allocation tags are set to 0 when a page is first mapped to user
space.  That no longer holds with the huge zero folio when init_on_free is
enabled.

Fix it by decoupling __GFP_ZEROTAGS from __GFP_ZERO, passing to
tag_clear_highpages() whether we want to also clear page content.

Invert the meaning of the tag_clear_highpages() return value to have
clearer semantics.

Reproduced with the huge zero folio by modifying the check_buffer_fill
arm64/mte selftest to use a 2 MiB area, after making sure that pages have
a non-0 tag set when freeing (note that, during boot, we will not actually
initialize tags, but only set KASAN_TAG_KERNEL in the page flags).

	$ ./check_buffer_fill
	1..20
	...
	not ok 17 Check initial tags with private mapping, sync error mode and mmap memory
	not ok 18 Check initial tags with private mapping, sync error mode and mmap/mprotect memory
	...

This code needs more cleanups; we'll tackle that next, like
decoupling __GFP_ZEROTAGS from __GFP_SKIP_KASAN.

[akpm@linux-foundation.org: s/__GPF_ZERO/__GFP_ZERO/, per David]
Link: https://lore.kernel.org/20260421-zerotags-v2-1-05cb1035482e@kernel.org
Fixes: adfb6609c680 ("mm/huge_memory: initialise the tags of the huge zero folio")
Signed-off-by: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Tested-by: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Liam Howlett &lt;liam@infradead.org&gt;
Cc: Lorenzo Stoakes (Oracle) &lt;ljs@kernel.org&gt;
Cc: Mark Brown &lt;broonie@kernel.org&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm/memory_hotplug: fix memory block reference leak on remove</title>
<updated>2026-06-01T15:50:41+00:00</updated>
<author>
<name>Muchun Song</name>
<email>songmuchun@bytedance.com</email>
</author>
<published>2026-04-28T08:52:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=09ce923071e7852ece60d7368e05249bf32c7967'/>
<id>urn:sha1:09ce923071e7852ece60d7368e05249bf32c7967</id>
<content type='text'>
commit 93866f55f7e292fe3d47d36c9efe5ee10213a06b upstream.

Patch series "mm: Fix memory block leaks and locking", v2.

This series fixes two memory block device reference leaks and one locking
issue around the per-memory_block hwpoison counter.


This patch (of 2):

remove_memory_blocks_and_altmaps() looks up each memory block with
find_memory_block(), which acquires a reference to the memory block
device.

That reference is never dropped on this path, resulting in a leaked device
reference when removing memory blocks and their altmaps.  Drop the
reference after retrieving mem-&gt;altmap and clearing mem-&gt;altmap, before
removing the memory block device.

Link: https://lore.kernel.org/20260428085219.1316047-1-songmuchun@bytedance.com
Link: https://lore.kernel.org/20260428085219.1316047-2-songmuchun@bytedance.com
Fixes: 6b8f0798b85a ("mm/memory_hotplug: split memmap_on_memory requests across memblocks")
Signed-off-by: Muchun Song &lt;songmuchun@bytedance.com&gt;
Acked-by: Oscar Salvador &lt;osalvador@suse.de&gt;
Acked-by: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Cc: Danilo Krummrich &lt;dakr@kernel.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: "Huang, Ying" &lt;huang.ying.caritas@gmail.com&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Naoya Horiguchi &lt;nao.horiguchi@gmail.com&gt;
Cc: "Rafael J. Wysocki" &lt;rafael@kernel.org&gt;
Cc: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm: fix __vm_normal_page() to handle missing support for pmd_special()/pud_special()</title>
<updated>2026-06-01T15:50:41+00:00</updated>
<author>
<name>David Hildenbrand (Arm)</name>
<email>david@kernel.org</email>
</author>
<published>2026-04-30T11:31:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=62153767e8fc3889bc6508e9ffe927aaf64c4334'/>
<id>urn:sha1:62153767e8fc3889bc6508e9ffe927aaf64c4334</id>
<content type='text'>
commit c0c6ccd9828c3a1950623b546fa57292a77b5c73 upstream.

On x86 32-bit with THP enabled, zap_huge_pmd() is seen to generate a
"WARNING: mm/memory.c:735 at __vm_normal_page+0x6a/0x7d", from the
VM_WARN_ON_ONCE(is_zero_pfn(pfn) || is_huge_zero_pfn(pfn)); followed by
"BUG: Bad rss-counter state"s, then later "BUG: Bad page state"s when
reclaim gets to call shrink_huge_zero_folio_scan().

It's as if the _PAGE_SPECIAL bit never got set in the huge_zero pmd: and
indeed, whereas pte_special() and pte_mkspecial() are subject to a
dedicated CONFIG_ARCH_HAS_PTE_SPECIAL, pmd_special() and pmd_mkspecial()
are subject to CONFIG_ARCH_SUPPORTS_PMD_PFNMAP, which is never enabled on
any 32-bit architecture.

While the problem was exposed through commit d80a9cb1a64a
("mm/huge_memory: add and use normal_or_softleaf_folio_pmd()"), it was an
oversight in commit af38538801c6 ("mm/memory: factor out common code from
vm_normal_page_*()") and would result in other problems:
* huge zero folio accounted in smaps, pagemap (PAGE_IS_FILE) and
  numamaps as file-backed THP
* folio_walk_start() returning the folio even without FW_ZEROPAGE set.
  Callers seem to tolerate that, though.

... and triggering the VM_WARN_ON_ONE(), although never reported so far.

To fix it, teach vm_normal_page_pmd()/vm_normal_page_pud() to consider
whether pmd_special/pud_special is actually implemented.

Link: https://lore.kernel.org/20260430-pmd_special-v1-1-dbcbcfd72c20@kernel.org
Fixes: af38538801c6 ("mm/memory: factor out common code from vm_normal_page_*()")
Signed-off-by: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Reported-by: Hugh Dickins &lt;hughd@google.com&gt;
Closes: https://lore.kernel.org/r/74a75b59-2e13-3985-ee99-d5521f39df2a@google.com
Reported-by: Bibo Mao &lt;maobibo@loongson.cn&gt;
Closes: https://lore.kernel.org/r/20260430041121.2839350-1-maobibo@loongson.cn
Debugged-by: Hugh Dickins &lt;hughd@google.com&gt;
Reviewed-by: Lance Yang &lt;lance.yang@linux.dev&gt;
Tested-by: Bibo Mao &lt;maobibo@loongson.cn&gt;
Reviewed-by: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Reviewed-by: Oscar Salvador &lt;osalvador@suse.de&gt;
Reviewed-by: Lorenzo Stoakes &lt;ljs@kernel.org&gt;
Cc: Liam R. Howlett &lt;liam@infradead.org&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Vlastimil Babka &lt;vbabka@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm/memory: fix spurious warning when unmapping device-private/exclusive pages</title>
<updated>2026-06-01T15:50:41+00:00</updated>
<author>
<name>Alistair Popple</name>
<email>apopple@nvidia.com</email>
</author>
<published>2026-05-01T06:51:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2fff0cdd942261497fb8922a194b4da3315ae864'/>
<id>urn:sha1:2fff0cdd942261497fb8922a194b4da3315ae864</id>
<content type='text'>
commit be3f38d05cc5a7c3f13e51994c5dd043ab604d28 upstream.

Device private and exclusive entries are only supported for anonymous
folios.  This condition is tested in __migrate_device_pages() and
make_device_exclusive() using folio_test_anon().  However the unmap path
tests this assumption using vma_is_anonymous().

This is wrong because whilst anonymous VMAs can only contain folios where
folio_test_anon() is true the opposite relation does not hold.  A folio
for which folio_test_anon() is true does not imply vma_is_anonymous() is
true.  Such a condition can occur if for example a folio is part of a
private filebacked mapping.

In this case vma_is_anonymous() is false as the mapping is filebacked, but
folio_test_anon() may be true, thus permitting devices to migrate the
folio to device private memory.  This can lead to the following spurious
warnings during process teardown:

[  772.737706] ------------[ cut here ]------------
[  772.739201] WARNING: mm/memory.c:1754 at unmap_page_range.cold+0x26/0x18a, CPU#17: hmm-tests/2041
[  772.742050] Modules linked in: test_hmm nvidia_uvm(O) nvidia(O)
[  772.743959] CPU: 17 UID: 0 PID: 2041 Comm: hmm-tests Tainted: G        W  O        7.0.0+ #387 PREEMPT(full)
[  772.747104] Tainted: [W]=WARN, [O]=OOT_MODULE
[  772.748509] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014
[  772.752117] RIP: 0010:unmap_page_range.cold+0x26/0x18a
[  772.753780] Code: 7e fe ff ff 48 89 4c 24 78 4c 89 44 24 38 e8 f2 ff b1 00 48 8b 4c 24 78 4c 8b 44 24 38 48 8b 44 24 18 48 83 78 48 00 74 04 90 &lt;0f&gt; 0b 90 48 89 ca b8 ff ff 37 00 48 c1 ea 03 48 c1 e0 2a 80 3c 02
[  772.759602] RSP: 0018:ffff888112607550 EFLAGS: 00010286
[  772.761310] RAX: ffff88811bbf4dc0 RBX: dffffc0000000000 RCX: ffffea03e9bfffd8
[  772.763583] RDX: 1ffff1102377e9c1 RSI: 0000000000000008 RDI: ffff88811bbf4e08
[  772.765914] RBP: 0000000000000006 R08: ffff8881059f7448 R09: ffffed10224c0e68
[  772.768184] R10: ffff888112607347 R11: 0000000000000001 R12: 0000000000000001
[  772.770461] R13: ffffea03e9bfffc0 R14: ffff888112607908 R15: ffffea03e9bfffc0
[  772.772782] FS:  00007f327caa2780(0000) GS:ffff888427b7d000(0000) knlGS:0000000000000000
[  772.775328] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  772.777187] CR2: 00007f327ca89000 CR3: 00000001994d5000 CR4: 00000000000006f0
[  772.779135] Call Trace:
[  772.779792]  &lt;TASK&gt;
[  772.780317]  ? dmirror_interval_invalidate+0x1a3/0x290 [test_hmm]
[  772.781873]  ? vm_normal_page_pud+0x2b0/0x2b0
[  772.782992]  ? __rwlock_init+0x150/0x150
[  772.784006]  ? lock_release+0x216/0x2b0
[  772.785008]  ? __mmu_notifier_invalidate_range_start+0x505/0x6e0
[  772.786522]  ? lock_release+0x216/0x2b0
[  772.787498]  ? unmap_single_vma+0xb6/0x210
[  772.788573]  unmap_vmas+0x27d/0x520
[  772.789506]  ? unmap_single_vma+0x210/0x210
[  772.790607]  ? mas_update_gap.part.0+0x620/0x620
[  772.791834]  unmap_region+0x19e/0x350
[  772.792769]  ? remove_vma+0x130/0x130
[  772.793684]  ? mas_alloc_nodes+0x1f2/0x300
[  772.794730]  vms_complete_munmap_vmas+0x8c1/0xe20
[  772.795926]  ? unmap_region+0x350/0x350
[  772.796917]  do_vmi_align_munmap+0x36a/0x4e0
[  772.798018]  ? lock_release+0x216/0x2b0
[  772.799024]  ? vma_shrink+0x620/0x620
[  772.799983]  do_vmi_munmap+0x150/0x2c0
[  772.800939]  __vm_munmap+0x161/0x2c0
[  772.801872]  ? expand_downwards+0xd60/0xd60
[  772.802948]  ? clockevents_program_event+0x1ef/0x540
[  772.804217]  ? lock_release+0x216/0x2b0
[  772.805158]  __x64_sys_munmap+0x59/0x80
[  772.805776]  do_syscall_64+0xfc/0x670
[  772.806336]  ? irqentry_exit+0xda/0x580
[  772.806976]  entry_SYSCALL_64_after_hwframe+0x4b/0x53
[  772.807772] RIP: 0033:0x7f327cbb2717
[  772.808323] Code: 73 01 c3 48 8b 0d f9 76 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d c9 76 0d 00 f7 d8 64 89 01 48
[  772.811337] RSP: 002b:00007ffde7f57d38 EFLAGS: 00000202 ORIG_RAX: 000000000000000b
[  772.812564] RAX: ffffffffffffffda RBX: 00007f327cc9c000 RCX: 00007f327cbb2717
[  772.813733] RDX: 0000000000000000 RSI: 0000000000400000 RDI: 00007f327c289000
[  772.814867] RBP: 0000000000421360 R08: 000000000000001a R09: 0000000000000000
[  772.815991] R10: 0000000000000003 R11: 0000000000000202 R12: 00007ffde7f57d74
[  772.817121] R13: 00007f327c689010 R14: 0000000000100000 R15: 00007f327c289000
[  772.818272]  &lt;/TASK&gt;
[  772.818614] irq event stamp: 0
[  772.819159] hardirqs last  enabled at (0): [&lt;0000000000000000&gt;] 0x0
[  772.820174] hardirqs last disabled at (0): [&lt;ffffffff82a57ab3&gt;] copy_process+0x19f3/0x6440
[  772.821511] softirqs last  enabled at (0): [&lt;ffffffff82a57b00&gt;] copy_process+0x1a40/0x6440
[  772.822869] softirqs last disabled at (0): [&lt;0000000000000000&gt;] 0x0
[  772.823871] ---[ end trace 0000000000000000 ]---

Fix this by using the same check for folio_test_anon() in
zap_nonpresent_ptes(). Also add a hmm-test case for this.

Link: https://lore.kernel.org/20260501065116.2057242-1-apopple@nvidia.com
Fixes: 999dad824c39 ("mm/shmem: persist uffd-wp bit across zapping for file-backed")
Signed-off-by: Alistair Popple &lt;apopple@nvidia.com&gt;
Reported-by: Arsen Arsenović &lt;aarsenovic@baylibre.com&gt;
Reviewed-by: Balbir Singh &lt;balbirs@nvidia.com&gt;
Cc: David Hildenbrand &lt;david@kernel.org&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: John Hubbard &lt;jhubbard@nvidia.com&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam R. Howlett &lt;liam@infradead.org&gt;
Cc: Lorenzo Stoakes &lt;ljs@kernel.org&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Shuah Khan &lt;shuah@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Cc: Vlastimil Babka &lt;vbabka@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm/damon/sysfs-schemes: call missing mem_cgroup_iter_break()</title>
<updated>2026-06-01T15:50:39+00:00</updated>
<author>
<name>SeongJae Park</name>
<email>sj@kernel.org</email>
</author>
<published>2026-04-26T17:36:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=302e02f9ba49f81418ec2a749ae6f5cac1d424e9'/>
<id>urn:sha1:302e02f9ba49f81418ec2a749ae6f5cac1d424e9</id>
<content type='text'>
commit d4e7b5c4cc353f154d5ab8bb2e1ce7714d77a6e9 upstream.

damon_sysfs_memcg_path_to_id() breaks mem_cgroup_iter() loop without
calling mem_cgroup_iter_break().  This leaks the cgroup reference.  Fix
the issue by calling mem_cgroup_iter_break() before the break.

The issue was discovered [1] by Sashiko.

Link: https://lore.kernel.org/20260426173625.86521-1-sj@kernel.org
Link: https://lore.kernel.org/20260423004148.74722-1-sj@kernel.org [1]
Fixes: 29cbb9a13f05 ("mm/damon/sysfs-schemes: implement scheme filters")
Signed-off-by: SeongJae Park &lt;sj@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 6.3.x
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>memblock: reserve_mem: fix end caclulation in reserve_mem_release_by_name()</title>
<updated>2026-05-23T11:06:53+00:00</updated>
<author>
<name>Mike Rapoport (Microsoft)</name>
<email>rppt@kernel.org</email>
</author>
<published>2026-03-23T07:48:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7377e48f9ca8b45420bde4e74da88af2b708d59e'/>
<id>urn:sha1:7377e48f9ca8b45420bde4e74da88af2b708d59e</id>
<content type='text'>
[ Upstream commit c12c3e1507809ad1fc0448f51c933f52e17d13cd ]

free_reserved_area() expects end parameter to point to the first address
after the area, but reserve_mem_release_by_name() passes it the last
address inside the area.

Remove subtraction of one in calculation of the area end.

Fixes: 74e2498ccf7b ("mm/memblock: Add reserved memory release function")
Link: https://patch.msgid.link/20260323074836.3653702-2-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>mm/damon/core: disallow time-quota setting zero esz</title>
<updated>2026-05-17T15:15:35+00:00</updated>
<author>
<name>SeongJae Park</name>
<email>sj@kernel.org</email>
</author>
<published>2026-04-07T00:31:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=a9591e4083cc703fb3fe272b0cdcbe0a213538df'/>
<id>urn:sha1:a9591e4083cc703fb3fe272b0cdcbe0a213538df</id>
<content type='text'>
commit 8bbde987c2b84f80da0853f739f0a920386f8b99 upstream.

When the throughput of a DAMOS scheme is very slow, DAMOS time quota can
make the effective size quota smaller than damon_ctx-&gt;min_region_sz.  In
the case, damos_apply_scheme() will skip applying the action, because the
action is tried at region level, which requires &gt;=min_region_sz size.
That is, the quota is effectively exceeded for the quota charge window.

Because no action will be applied, the total_charged_sz and
total_charged_ns are also not updated.  damos_set_effective_quota() will
try to update the effective size quota before starting the next charge
window.  However, because the total_charged_sz and total_charged_ns have
not updated, the throughput and effective size quota are also not changed.
Since effective size quota can only be decreased, other effective size
quota update factors including DAMOS quota goals and size quota cannot
make any change, either.

As a result, the scheme is unexpectedly deactivated until the user notices
and mitigates the situation.  The users can mitigate this situation by
changing the time quota online or re-install the scheme.  While the
mitigation is somewhat straightforward, finding the situation would be
challenging, because DAMON is not providing good observabilities for that.
Even if such observability is provided, doing the additional monitoring
and the mitigation is somewhat cumbersome and not aligned to the intention
of the time quota.  The time quota was intended to help reduce the user's
administration overhead.

Fix the problem by setting time quota-modified effective size quota be at
least min_region_sz always.

The issue was discovered [1] by sashiko.

Link: https://lore.kernel.org/20260407003153.79589-1-sj@kernel.org
Link: https://lore.kernel.org/20260405192504.110014-1-sj@kernel.org [1]
Fixes: 1cd243030059 ("mm/damon/schemes: implement time quota")
Signed-off-by: SeongJae Park &lt;sj@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 5.16.x
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm/damon/reclaim: detect and use fresh enabled and kdamond_pid values</title>
<updated>2026-05-17T15:15:35+00:00</updated>
<author>
<name>SeongJae Park</name>
<email>sj@kernel.org</email>
</author>
<published>2026-04-19T16:10:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d893804e9e3bd29e14d52813a8648a552417f826'/>
<id>urn:sha1:d893804e9e3bd29e14d52813a8648a552417f826</id>
<content type='text'>
commit 64a140afa5ed1c6f5ba6d451512cbdbbab1ba339 upstream.

Patch series "mm/damon/modules: detect and use fresh status", v3.

DAMON modules including DAMON_RECLAIM, DAMON_LRU_SORT and DAMON_STAT
commonly expose the kdamond running status via their parameters.  Under
certain scenarios including wrong user inputs and memory allocation
failures, those parameter values can be stale.  It can confuse users.  For
DAMON_RECLAIM and DAMON_LRU_SORT, it even makes the kdamond unable to be
restarted before the system reboot.

The problem comes from the fact that there are multiple events for the
status changes and it is difficult to follow up all the scenarios.  Fix
the issue by detecting and using the status on demand, instead of using a
cached status that is difficult to be updated.

Patches 1-3 fix the bugs in DAMON_RECLAIM, DAMON_LRU_SORT and DAMON_STAT
in the order.


This patch (of 3):

DAMON_RECLAIM updates 'enabled' and 'kdamond_pid' parameter values, which
represents the running status of its kdamond, when the user explicitly
requests start/stop of the kdamond.  The kdamond can, however, be stopped
in events other than the explicit user request in the following three
events.

1. ctx-&gt;regions_score_histogram allocation failure at beginning of the
   execution,
2. damon_commit_ctx() failure due to invalid user input, and
3. damon_commit_ctx() failure due to its internal allocation failures.

Hence, if the kdamond is stopped by the above three events, the values of
the status parameters can be stale.  Users could show the stale values and
be confused.  This is already bad, but the real consequence is worse.
DAMON_RECLAIM avoids unnecessary damon_start() and damon_stop() calls
based on the 'enabled' parameter value.  And the update of 'enabled'
parameter value depends on the damon_start() and damon_stop() call
results.  Hence, once the kdamond has stopped by the unintentional events,
the user cannot restart the kdamond before the system reboot.  For
example, the issue can be reproduced via below steps.

    # cd /sys/module/damon_reclaim/parameters
    #
    # # start DAMON_RECLAIM
    # echo Y &gt; enabled
    # ps -ef | grep kdamond
    root         806       2  0 17:53 ?        00:00:00 [kdamond.0]
    root         808     803  0 17:53 pts/4    00:00:00 grep kdamond
    #
    # # commit wrong input to stop kdamond withou explicit stop request
    # echo 3 &gt; addr_unit
    # echo Y &gt; commit_inputs
    bash: echo: write error: Invalid argument
    #
    # # confirm kdamond is stopped
    # ps -ef | grep kdamond
    root         811     803  0 17:53 pts/4    00:00:00 grep kdamond
    #
    # # users casn now show stable status
    # cat enabled
    Y
    # cat kdamond_pid
    806
    #
    # # even after fixing the wrong parameter,
    # # kdamond cannot be restarted.
    # echo 1 &gt; addr_unit
    # echo Y &gt; enabled
    # ps -ef | grep kdamond
    root         815     803  0 17:54 pts/4    00:00:00 grep kdamond

The problem will only rarely happen in real and common setups for the
following reasons.  The allocation failures are unlikely in such setups
since those allocations are arguably too small to fail.  Also sane users
on real production environments may not commit wrong input parameters.
But once it happens, the consequence is quite bad.  And the bug is a bug.

The issue stems from the fact that there are multiple events that can
change the status, and following all the events is challenging.
Dynamically detect and use the fresh status for the parameters when those
are requested.

Link: https://lore.kernel.org/20260419161003.79176-1-sj@kernel.org
Link: https://lore.kernel.org/20260419161003.79176-2-sj@kernel.org
Fixes: e035c280f6df ("mm/damon/reclaim: support online inputs update")
Co-developed-by: Liew Rui Yan &lt;aethernet65535@gmail.com&gt;
Signed-off-by: Liew Rui Yan &lt;aethernet65535@gmail.com&gt;
Signed-off-by: SeongJae Park &lt;sj@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 5.19.x
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm/damon/lru_sort: detect and use fresh enabled and kdamond_pid values</title>
<updated>2026-05-17T15:15:35+00:00</updated>
<author>
<name>SeongJae Park</name>
<email>sj@kernel.org</email>
</author>
<published>2026-04-19T16:10:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4697ed7be9b991c9790fa322b3e7302491704668'/>
<id>urn:sha1:4697ed7be9b991c9790fa322b3e7302491704668</id>
<content type='text'>
commit b98b7ff6025ae82570d4915e083f0cbd8d48b3cf upstream.

DAMON_LRU_SORT updates 'enabled' and 'kdamond_pid' parameter values, which
represents the running status of its kdamond, when the user explicitly
requests start/stop of the kdamond.  The kdamond can, however, be stopped
in events other than the explicit user request in the following three
events.

1. ctx-&gt;regions_score_histogram allocation failure at beginning of the
   execution,
2. damon_commit_ctx() failure due to invalid user input, and
3. damon_commit_ctx() failure due to its internal allocation failures.

Hence, if the kdamond is stopped by the above three events, the values of
the status parameters can be stale.  Users could show the stale values and
be confused.  This is already bad, but the real consequence is worse.
DAMON_LRU_SORT avoids unnecessary damon_start() and damon_stop() calls
based on the 'enabled' parameter value.  And the update of 'enabled'
parameter value depends on the damon_start() and damon_stop() call
results.  Hence, once the kdamond has stopped by the unintentional events,
the user cannot restart the kdamond before the system reboot.  For
example, the issue can be reproduced via below steps.

    # cd /sys/module/damon_lru_sort/parameters
    #
    # # start DAMON_LRU_SORT
    # echo Y &gt; enabled
    # ps -ef | grep kdamond
    root         806       2  0 17:53 ?        00:00:00 [kdamond.0]
    root         808     803  0 17:53 pts/4    00:00:00 grep kdamond
    #
    # # commit wrong input to stop kdamond withou explicit stop request
    # echo 3 &gt; addr_unit
    # echo Y &gt; commit_inputs
    bash: echo: write error: Invalid argument
    #
    # # confirm kdamond is stopped
    # ps -ef | grep kdamond
    root         811     803  0 17:53 pts/4    00:00:00 grep kdamond
    #
    # # users casn now show stable status
    # cat enabled
    Y
    # cat kdamond_pid
    806
    #
    # # even after fixing the wrong parameter,
    # # kdamond cannot be restarted.
    # echo 1 &gt; addr_unit
    # echo Y &gt; enabled
    # ps -ef | grep kdamond
    root         815     803  0 17:54 pts/4    00:00:00 grep kdamond

The problem will only rarely happen in real and common setups for the
following reasons.  The allocation failures are unlikely in such setups
since those allocations are arguably too small to fail.  Also sane users
on real production environments may not commit wrong input parameters.
But once it happens, the consequence is quite bad.  And the bug is a bug.

The issue stems from the fact that there are multiple events that can
change the status, and following all the events is challenging.
Dynamically detect and use the fresh status for the parameters when those
are requested.

Link: https://lore.kernel.org/20260419161003.79176-3-sj@kernel.org
Fixes: 40e983cca927 ("mm/damon: introduce DAMON-based LRU-lists Sorting")
Co-developed-by: Liew Rui Yan &lt;aethernet65535@gmail.com&gt;
Signed-off-by: Liew Rui Yan &lt;aethernet65535@gmail.com&gt;
Signed-off-by: SeongJae Park &lt;sj@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 6.0.x
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
