<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/include, branch v6.14-rc6</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge tag 'mm-hotfixes-stable-2025-03-08-16-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2025-03-09T00:34:06+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-09T00:34:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1110ce6a1e34fe1fdc1bfe4ad52405f327d5083b'/>
<id>1110ce6a1e34fe1fdc1bfe4ad52405f327d5083b</id>
<content type='text'>
Pull misc fixes from Andrew Morton:
 "33 hotfixes. 24 are cc:stable and the remainder address post-6.13
  issues or aren't considered necessary for -stable kernels.

  26 are for MM and 7 are for non-MM.

   - "mm: memory_failure: unmap poisoned folio during migrate properly"
     from Ma Wupeng fixes a couple of two year old bugs involving the
     migration of hwpoisoned folios.

   - "selftests/damon: three fixes for false results" from SeongJae Park
     fixes three one year old bugs in the SAMON selftest code.

  The remainder are singletons and doubletons. Please see the individual
  changelogs for details"

* tag 'mm-hotfixes-stable-2025-03-08-16-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (33 commits)
  mm/page_alloc: fix uninitialized variable
  rapidio: add check for rio_add_net() in rio_scan_alloc_net()
  rapidio: fix an API misues when rio_add_net() fails
  MAINTAINERS: .mailmap: update Sumit Garg's email address
  Revert "mm/page_alloc.c: don't show protection in zone's -&gt;lowmem_reserve[] for empty zone"
  mm: fix finish_fault() handling for large folios
  mm: don't skip arch_sync_kernel_mappings() in error paths
  mm: shmem: remove unnecessary warning in shmem_writepage()
  userfaultfd: fix PTE unmapping stack-allocated PTE copies
  userfaultfd: do not block on locking a large folio with raised refcount
  mm: zswap: use ATOMIC_LONG_INIT to initialize zswap_stored_pages
  mm: shmem: fix potential data corruption during shmem swapin
  mm: fix kernel BUG when userfaultfd_move encounters swapcache
  selftests/damon/damon_nr_regions: sort collected regiosn before checking with min/max boundaries
  selftests/damon/damon_nr_regions: set ops update for merge results check to 100ms
  selftests/damon/damos_quota: make real expectation of quota exceeds
  include/linux/log2.h: mark is_power_of_2() with __always_inline
  NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback
  mm, swap: avoid BUG_ON in relocate_cluster()
  mm: swap: use correct step in loop to wait all clusters in wait_for_allocation()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull misc fixes from Andrew Morton:
 "33 hotfixes. 24 are cc:stable and the remainder address post-6.13
  issues or aren't considered necessary for -stable kernels.

  26 are for MM and 7 are for non-MM.

   - "mm: memory_failure: unmap poisoned folio during migrate properly"
     from Ma Wupeng fixes a couple of two year old bugs involving the
     migration of hwpoisoned folios.

   - "selftests/damon: three fixes for false results" from SeongJae Park
     fixes three one year old bugs in the SAMON selftest code.

  The remainder are singletons and doubletons. Please see the individual
  changelogs for details"

* tag 'mm-hotfixes-stable-2025-03-08-16-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (33 commits)
  mm/page_alloc: fix uninitialized variable
  rapidio: add check for rio_add_net() in rio_scan_alloc_net()
  rapidio: fix an API misues when rio_add_net() fails
  MAINTAINERS: .mailmap: update Sumit Garg's email address
  Revert "mm/page_alloc.c: don't show protection in zone's -&gt;lowmem_reserve[] for empty zone"
  mm: fix finish_fault() handling for large folios
  mm: don't skip arch_sync_kernel_mappings() in error paths
  mm: shmem: remove unnecessary warning in shmem_writepage()
  userfaultfd: fix PTE unmapping stack-allocated PTE copies
  userfaultfd: do not block on locking a large folio with raised refcount
  mm: zswap: use ATOMIC_LONG_INIT to initialize zswap_stored_pages
  mm: shmem: fix potential data corruption during shmem swapin
  mm: fix kernel BUG when userfaultfd_move encounters swapcache
  selftests/damon/damon_nr_regions: sort collected regiosn before checking with min/max boundaries
  selftests/damon/damon_nr_regions: set ops update for merge results check to 100ms
  selftests/damon/damos_quota: make real expectation of quota exceeds
  include/linux/log2.h: mark is_power_of_2() with __always_inline
  NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback
  mm, swap: avoid BUG_ON in relocate_cluster()
  mm: swap: use correct step in loop to wait all clusters in wait_for_allocation()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'acpi-6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2025-03-07T22:17:42+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-07T22:17:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d4fd25b6f883db41194e1760041560779d412d98'/>
<id>d4fd25b6f883db41194e1760041560779d412d98</id>
<content type='text'>
Pull ACPI fix from Rafael Wysocki:
 "Restore the previous behavior of the ACPI platform_profile sysfs
  interface that has been changed recently in a way incompatible with
  the existing user space (Mario Limonciello)"

* tag 'acpi-6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  platform/x86/amd: pmf: Add balanced-performance to hidden choices
  platform/x86/amd: pmf: Add 'quiet' to hidden choices
  ACPI: platform_profile: Add support for hidden choices
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ACPI fix from Rafael Wysocki:
 "Restore the previous behavior of the ACPI platform_profile sysfs
  interface that has been changed recently in a way incompatible with
  the existing user space (Mario Limonciello)"

* tag 'acpi-6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  platform/x86/amd: pmf: Add balanced-performance to hidden choices
  platform/x86/amd: pmf: Add 'quiet' to hidden choices
  ACPI: platform_profile: Add support for hidden choices
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'block-6.14-20250306' of git://git.kernel.dk/linux</title>
<updated>2025-03-07T21:12:33+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-07T21:12:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=381af8d9f484c06d93e4a0b8459526e779b35a65'/>
<id>381af8d9f484c06d93e4a0b8459526e779b35a65</id>
<content type='text'>
Pull block fixes from Jens Axboe:

 - NVMe pull request via Keith:
      - TCP use after free fix on polling (Sagi)
      - Controller memory buffer cleanup fixes (Icenowy)
      - Free leaking requests on bad user passthrough commands (Keith)
      - TCP error message fix (Maurizio)
      - TCP corruption fix on partial PDU (Maurizio)
      - TCP memory ordering fix for weakly ordered archs (Meir)
      - Type coercion fix on message error for TCP (Dan)

 - Name the RQF flags enum, fixing issues with anon enums and BPF import
   of it

 - ublk parameter setting fix

 - GPT partition 7-bit conversion fix

* tag 'block-6.14-20250306' of git://git.kernel.dk/linux:
  block: Name the RQF flags enum
  nvme-tcp: fix signedness bug in nvme_tcp_init_connection()
  block: fix conversion of GPT partition name to 7-bit
  ublk: set_params: properly check if parameters can be applied
  nvmet-tcp: Fix a possible sporadic response drops in weakly ordered arch
  nvme-tcp: fix potential memory corruption in nvme_tcp_recv_pdu()
  nvme-tcp: Fix a C2HTermReq error message
  nvmet: remove old function prototype
  nvme-ioctl: fix leaked requests on mapping error
  nvme-pci: skip CMB blocks incompatible with PCI P2P DMA
  nvme-pci: clean up CMBMSC when registering CMB fails
  nvme-tcp: fix possible UAF in nvme_tcp_poll
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull block fixes from Jens Axboe:

 - NVMe pull request via Keith:
      - TCP use after free fix on polling (Sagi)
      - Controller memory buffer cleanup fixes (Icenowy)
      - Free leaking requests on bad user passthrough commands (Keith)
      - TCP error message fix (Maurizio)
      - TCP corruption fix on partial PDU (Maurizio)
      - TCP memory ordering fix for weakly ordered archs (Meir)
      - Type coercion fix on message error for TCP (Dan)

 - Name the RQF flags enum, fixing issues with anon enums and BPF import
   of it

 - ublk parameter setting fix

 - GPT partition 7-bit conversion fix

* tag 'block-6.14-20250306' of git://git.kernel.dk/linux:
  block: Name the RQF flags enum
  nvme-tcp: fix signedness bug in nvme_tcp_init_connection()
  block: fix conversion of GPT partition name to 7-bit
  ublk: set_params: properly check if parameters can be applied
  nvmet-tcp: Fix a possible sporadic response drops in weakly ordered arch
  nvme-tcp: fix potential memory corruption in nvme_tcp_recv_pdu()
  nvme-tcp: Fix a C2HTermReq error message
  nvmet: remove old function prototype
  nvme-ioctl: fix leaked requests on mapping error
  nvme-pci: skip CMB blocks incompatible with PCI P2P DMA
  nvme-pci: clean up CMBMSC when registering CMB fails
  nvme-tcp: fix possible UAF in nvme_tcp_poll
</pre>
</div>
</content>
</entry>
<entry>
<title>fs/pipe: add simpler helpers for common cases</title>
<updated>2025-03-07T04:25:35+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-07T04:25:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=00a7d39898c8010bfd5ff62af31ca5db34421b38'/>
<id>00a7d39898c8010bfd5ff62af31ca5db34421b38</id>
<content type='text'>
The fix to atomically read the pipe head and tail state when not holding
the pipe mutex has caused a number of headaches due to the size change
of the involved types.

It turns out that we don't have _that_ many places that access these
fields directly and were affected, but we have more than we strictly
should have, because our low-level helper functions have been designed
to have intimate knowledge of how the pipes work.

And as a result, that random noise of direct 'pipe-&gt;head' and
'pipe-&gt;tail' accesses makes it harder to pinpoint any actual potential
problem spots remaining.

For example, we didn't have a "is the pipe full" helper function, but
instead had a "given these pipe buffer indexes and this pipe size, is
the pipe full".  That's because some low-level pipe code does actually
want that much more complicated interface.

But most other places literally just want a "is the pipe full" helper,
and not having it meant that those places ended up being unnecessarily
much too aware of this all.

It would have been much better if only the very core pipe code that
cared had been the one aware of this all.

So let's fix it - better late than never.  This just introduces the
trivial wrappers for "is this pipe full or empty" and to get how many
pipe buffers are used, so that instead of writing

        if (pipe_full(pipe-&gt;head, pipe-&gt;tail, pipe-&gt;max_usage))

the places that literally just want to know if a pipe is full can just
say

        if (pipe_is_full(pipe))

instead.  The existing trivial cases were converted with a 'sed' script.

This cuts down on the places that access pipe-&gt;head and pipe-&gt;tail
directly outside of the pipe code (and core splice code) quite a lot.

The splice code in particular still revels in doing the direct low-level
accesses, and the fuse fuse_dev_splice_write() code also seems a bit
unnecessarily eager to go very low-level, but it's at least a bit better
than it used to be.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The fix to atomically read the pipe head and tail state when not holding
the pipe mutex has caused a number of headaches due to the size change
of the involved types.

It turns out that we don't have _that_ many places that access these
fields directly and were affected, but we have more than we strictly
should have, because our low-level helper functions have been designed
to have intimate knowledge of how the pipes work.

And as a result, that random noise of direct 'pipe-&gt;head' and
'pipe-&gt;tail' accesses makes it harder to pinpoint any actual potential
problem spots remaining.

For example, we didn't have a "is the pipe full" helper function, but
instead had a "given these pipe buffer indexes and this pipe size, is
the pipe full".  That's because some low-level pipe code does actually
want that much more complicated interface.

But most other places literally just want a "is the pipe full" helper,
and not having it meant that those places ended up being unnecessarily
much too aware of this all.

It would have been much better if only the very core pipe code that
cared had been the one aware of this all.

So let's fix it - better late than never.  This just introduces the
trivial wrappers for "is this pipe full or empty" and to get how many
pipe buffers are used, so that instead of writing

        if (pipe_full(pipe-&gt;head, pipe-&gt;tail, pipe-&gt;max_usage))

the places that literally just want to know if a pipe is full can just
say

        if (pipe_is_full(pipe))

instead.  The existing trivial cases were converted with a 'sed' script.

This cuts down on the places that access pipe-&gt;head and pipe-&gt;tail
directly outside of the pipe code (and core splice code) quite a lot.

The splice code in particular still revels in doing the direct low-level
accesses, and the fuse fuse_dev_splice_write() code also seems a bit
unnecessarily eager to go very low-level, but it's at least a bit better
than it used to be.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: Name the RQF flags enum</title>
<updated>2025-03-07T00:50:55+00:00</updated>
<author>
<name>Breno Leitao</name>
<email>leitao@debian.org</email>
</author>
<published>2025-03-06T16:27:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e7112524e5e885181cc5ae4d258f33b9dbe0b907'/>
<id>e7112524e5e885181cc5ae4d258f33b9dbe0b907</id>
<content type='text'>
Commit 5f89154e8e9e3445f9b59 ("block: Use enum to define RQF_x bit
indexes") converted the RQF flags to an anonymous enum, which was
a beneficial change. This patch goes one step further by naming the enum
as "rqf_flags".

This naming enables exporting these flags to BPF clients, eliminating
the need to duplicate these flags in BPF code. Instead, BPF clients can
now access the same kernel-side values through CO:RE (Compile Once, Run
Everywhere), as shown in this example:

    rqf_stats = bpf_core_enum_value(enum rqf_flags, __RQF_STATS)

Suggested-by: Yonghong Song &lt;yonghong.song@linux.dev&gt;
Signed-off-by: Breno Leitao &lt;leitao@debian.org&gt;
Link: https://lore.kernel.org/r/20250306-rqf_flags-v1-1-bbd64918b406@debian.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 5f89154e8e9e3445f9b59 ("block: Use enum to define RQF_x bit
indexes") converted the RQF flags to an anonymous enum, which was
a beneficial change. This patch goes one step further by naming the enum
as "rqf_flags".

This naming enables exporting these flags to BPF clients, eliminating
the need to duplicate these flags in BPF code. Instead, BPF clients can
now access the same kernel-side values through CO:RE (Compile Once, Run
Everywhere), as shown in this example:

    rqf_stats = bpf_core_enum_value(enum rqf_flags, __RQF_STATS)

Suggested-by: Yonghong Song &lt;yonghong.song@linux.dev&gt;
Signed-off-by: Breno Leitao &lt;leitao@debian.org&gt;
Link: https://lore.kernel.org/r/20250306-rqf_flags-v1-1-bbd64918b406@debian.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'vfs-6.14-rc6.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs</title>
<updated>2025-03-06T18:04:49+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-06T18:04:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7f0e9ee5e44887272627d0fcde0b19a675daf597'/>
<id>7f0e9ee5e44887272627d0fcde0b19a675daf597</id>
<content type='text'>
Pull vfs fixes from Christian Brauner:

 - Fix spelling mistakes in idmappings.rst

 - Fix RCU warnings in override_creds()/revert_creds()

 - Create new pid namespaces with default limit now that pid_max is
   namespaced

* tag 'vfs-6.14-rc6.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
  pid: Do not set pid_max in new pid namespaces
  doc: correcting two prefix errors in idmappings.rst
  cred: Fix RCU warnings in override/revert_creds
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull vfs fixes from Christian Brauner:

 - Fix spelling mistakes in idmappings.rst

 - Fix RCU warnings in override_creds()/revert_creds()

 - Create new pid namespaces with default limit now that pid_max is
   namespaced

* tag 'vfs-6.14-rc6.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
  pid: Do not set pid_max in new pid namespaces
  doc: correcting two prefix errors in idmappings.rst
  cred: Fix RCU warnings in override/revert_creds
</pre>
</div>
</content>
</entry>
<entry>
<title>fs/pipe: express 'pipe_empty()' in terms of 'pipe_occupancy()'</title>
<updated>2025-03-06T17:30:42+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-06T17:30:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=74d42bdb3a4673b1c10d1f457184e4d3c9cb0196'/>
<id>74d42bdb3a4673b1c10d1f457184e4d3c9cb0196</id>
<content type='text'>
That's what 'pipe_full()' does, so it's more consistent. But more
importantly it gets the type limits right when the pipe head and tail
are no longer necessarily 'unsigned int'.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
That's what 'pipe_full()' does, so it's more consistent. But more
importantly it gets the type limits right when the pipe head and tail
are no longer necessarily 'unsigned int'.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>include/linux/log2.h: mark is_power_of_2() with __always_inline</title>
<updated>2025-03-06T05:36:16+00:00</updated>
<author>
<name>Su Hui</name>
<email>suhui@nfschina.com</email>
</author>
<published>2025-02-21T07:16:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c29564d8b46f64f5e6e6f1c9c02f7761b7b90963'/>
<id>c29564d8b46f64f5e6e6f1c9c02f7761b7b90963</id>
<content type='text'>
When building kernel with randconfig, there is an error:

In function `kvm_is_cr4_bit_set',inlined from
`kvm_update_cpuid_runtime' at arch/x86/kvm/cpuid.c:310:9:

include/linux/compiler_types.h:542:38: error: call to
`__compiletime_assert_380' declared with attribute error:
BUILD_BUG_ON failed: !is_power_of_2(cr4_bit).

'!is_power_of_2(X86_CR4_OSXSAVE)' is False, but gcc treats is_power_of_2()
as non-inline function and a compilation error happens. Fix this by marking
is_power_of_2() with __always_inline.

Link: https://lkml.kernel.org/r/20250221071624.1356899-1-suhui@nfschina.com
Signed-off-by: Su Hui &lt;suhui@nfschina.com&gt;
Cc: Binbin Wu &lt;binbin.wu@linux.intel.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Sean Christopherson &lt;seanjc@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>
When building kernel with randconfig, there is an error:

In function `kvm_is_cr4_bit_set',inlined from
`kvm_update_cpuid_runtime' at arch/x86/kvm/cpuid.c:310:9:

include/linux/compiler_types.h:542:38: error: call to
`__compiletime_assert_380' declared with attribute error:
BUILD_BUG_ON failed: !is_power_of_2(cr4_bit).

'!is_power_of_2(X86_CR4_OSXSAVE)' is False, but gcc treats is_power_of_2()
as non-inline function and a compilation error happens. Fix this by marking
is_power_of_2() with __always_inline.

Link: https://lkml.kernel.org/r/20250221071624.1356899-1-suhui@nfschina.com
Signed-off-by: Su Hui &lt;suhui@nfschina.com&gt;
Cc: Binbin Wu &lt;binbin.wu@linux.intel.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Sean Christopherson &lt;seanjc@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback</title>
<updated>2025-03-06T05:36:15+00:00</updated>
<author>
<name>Mike Snitzer</name>
<email>snitzer@kernel.org</email>
</author>
<published>2025-02-25T02:20:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ce6d9c1c2b5cc785016faa11b48b6cd317eb367e'/>
<id>ce6d9c1c2b5cc785016faa11b48b6cd317eb367e</id>
<content type='text'>
Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so
nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd.

Otherwise NFS can deadlock waiting for kcompactd enduced writeback which
recurses back to NFS (which triggers writeback to NFSD via NFS loopback
mount on the same host, NFSD blocks waiting for XFS's call to
__filemap_get_folio):

6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds.

{---
[58] "kcompactd0"
[&lt;0&gt;] folio_wait_bit+0xe8/0x200
[&lt;0&gt;] folio_wait_writeback+0x2b/0x80
[&lt;0&gt;] nfs_wb_folio+0x80/0x1b0 [nfs]
[&lt;0&gt;] nfs_release_folio+0x68/0x130 [nfs]
[&lt;0&gt;] split_huge_page_to_list_to_order+0x362/0x840
[&lt;0&gt;] migrate_pages_batch+0x43d/0xb90
[&lt;0&gt;] migrate_pages_sync+0x9a/0x240
[&lt;0&gt;] migrate_pages+0x93c/0x9f0
[&lt;0&gt;] compact_zone+0x8e2/0x1030
[&lt;0&gt;] compact_node+0xdb/0x120
[&lt;0&gt;] kcompactd+0x121/0x2e0
[&lt;0&gt;] kthread+0xcf/0x100
[&lt;0&gt;] ret_from_fork+0x31/0x40
[&lt;0&gt;] ret_from_fork_asm+0x1a/0x30
---}

[akpm@linux-foundation.org: fix build]
Link: https://lkml.kernel.org/r/20250225022002.26141-1-snitzer@kernel.org
Fixes: 96780ca55e3c ("NFS: fix up nfs_release_folio() to try to release the page")
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Cc: Anna Schumaker &lt;anna.schumaker@oracle.com&gt;
Cc: Trond Myklebust &lt;trond.myklebust@hammerspace.com&gt;
Cc: &lt;stable@vger.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>
Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so
nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd.

Otherwise NFS can deadlock waiting for kcompactd enduced writeback which
recurses back to NFS (which triggers writeback to NFSD via NFS loopback
mount on the same host, NFSD blocks waiting for XFS's call to
__filemap_get_folio):

6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds.

{---
[58] "kcompactd0"
[&lt;0&gt;] folio_wait_bit+0xe8/0x200
[&lt;0&gt;] folio_wait_writeback+0x2b/0x80
[&lt;0&gt;] nfs_wb_folio+0x80/0x1b0 [nfs]
[&lt;0&gt;] nfs_release_folio+0x68/0x130 [nfs]
[&lt;0&gt;] split_huge_page_to_list_to_order+0x362/0x840
[&lt;0&gt;] migrate_pages_batch+0x43d/0xb90
[&lt;0&gt;] migrate_pages_sync+0x9a/0x240
[&lt;0&gt;] migrate_pages+0x93c/0x9f0
[&lt;0&gt;] compact_zone+0x8e2/0x1030
[&lt;0&gt;] compact_node+0xdb/0x120
[&lt;0&gt;] kcompactd+0x121/0x2e0
[&lt;0&gt;] kthread+0xcf/0x100
[&lt;0&gt;] ret_from_fork+0x31/0x40
[&lt;0&gt;] ret_from_fork_asm+0x1a/0x30
---}

[akpm@linux-foundation.org: fix build]
Link: https://lkml.kernel.org/r/20250225022002.26141-1-snitzer@kernel.org
Fixes: 96780ca55e3c ("NFS: fix up nfs_release_folio() to try to release the page")
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Cc: Anna Schumaker &lt;anna.schumaker@oracle.com&gt;
Cc: Trond Myklebust &lt;trond.myklebust@hammerspace.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/hugetlb: wait for hugetlb folios to be freed</title>
<updated>2025-03-06T05:36:14+00:00</updated>
<author>
<name>Ge Yang</name>
<email>yangge1116@126.com</email>
</author>
<published>2025-02-19T03:46:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=67bab13307c83fb742c2556b06cdc39dbad27f07'/>
<id>67bab13307c83fb742c2556b06cdc39dbad27f07</id>
<content type='text'>
Since the introduction of commit c77c0a8ac4c52 ("mm/hugetlb: defer freeing
of huge pages if in non-task context"), which supports deferring the
freeing of hugetlb pages, the allocation of contiguous memory through
cma_alloc() may fail probabilistically.

In the CMA allocation process, if it is found that the CMA area is
occupied by in-use hugetlb folios, these in-use hugetlb folios need to be
migrated to another location.  When there are no available hugetlb folios
in the free hugetlb pool during the migration of in-use hugetlb folios,
new folios are allocated from the buddy system.  A temporary state is set
on the newly allocated folio.  Upon completion of the hugetlb folio
migration, the temporary state is transferred from the new folios to the
old folios.  Normally, when the old folios with the temporary state are
freed, it is directly released back to the buddy system.  However, due to
the deferred freeing of hugetlb pages, the PageBuddy() check fails,
ultimately leading to the failure of cma_alloc().

Here is a simplified call trace illustrating the process:
cma_alloc()
    -&gt;__alloc_contig_migrate_range() // Migrate in-use hugetlb folios
        -&gt;unmap_and_move_huge_page()
            -&gt;folio_putback_hugetlb() // Free old folios
    -&gt;test_pages_isolated()
        -&gt;__test_page_isolated_in_pageblock()
             -&gt;PageBuddy(page) // Check if the page is in buddy

To resolve this issue, we have implemented a function named
wait_for_freed_hugetlb_folios().  This function ensures that the hugetlb
folios are properly released back to the buddy system after their
migration is completed.  By invoking wait_for_freed_hugetlb_folios()
before calling PageBuddy(), we ensure that PageBuddy() will succeed.

Link: https://lkml.kernel.org/r/1739936804-18199-1-git-send-email-yangge1116@126.com
Fixes: c77c0a8ac4c5 ("mm/hugetlb: defer freeing of huge pages if in non-task context")
Signed-off-by: Ge Yang &lt;yangge1116@126.com&gt;
Reviewed-by: Muchun Song &lt;muchun.song@linux.dev&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Barry Song &lt;21cnbao@gmail.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: &lt;stable@vger.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>
Since the introduction of commit c77c0a8ac4c52 ("mm/hugetlb: defer freeing
of huge pages if in non-task context"), which supports deferring the
freeing of hugetlb pages, the allocation of contiguous memory through
cma_alloc() may fail probabilistically.

In the CMA allocation process, if it is found that the CMA area is
occupied by in-use hugetlb folios, these in-use hugetlb folios need to be
migrated to another location.  When there are no available hugetlb folios
in the free hugetlb pool during the migration of in-use hugetlb folios,
new folios are allocated from the buddy system.  A temporary state is set
on the newly allocated folio.  Upon completion of the hugetlb folio
migration, the temporary state is transferred from the new folios to the
old folios.  Normally, when the old folios with the temporary state are
freed, it is directly released back to the buddy system.  However, due to
the deferred freeing of hugetlb pages, the PageBuddy() check fails,
ultimately leading to the failure of cma_alloc().

Here is a simplified call trace illustrating the process:
cma_alloc()
    -&gt;__alloc_contig_migrate_range() // Migrate in-use hugetlb folios
        -&gt;unmap_and_move_huge_page()
            -&gt;folio_putback_hugetlb() // Free old folios
    -&gt;test_pages_isolated()
        -&gt;__test_page_isolated_in_pageblock()
             -&gt;PageBuddy(page) // Check if the page is in buddy

To resolve this issue, we have implemented a function named
wait_for_freed_hugetlb_folios().  This function ensures that the hugetlb
folios are properly released back to the buddy system after their
migration is completed.  By invoking wait_for_freed_hugetlb_folios()
before calling PageBuddy(), we ensure that PageBuddy() will succeed.

Link: https://lkml.kernel.org/r/1739936804-18199-1-git-send-email-yangge1116@126.com
Fixes: c77c0a8ac4c5 ("mm/hugetlb: defer freeing of huge pages if in non-task context")
Signed-off-by: Ge Yang &lt;yangge1116@126.com&gt;
Reviewed-by: Muchun Song &lt;muchun.song@linux.dev&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Barry Song &lt;21cnbao@gmail.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
