<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/io_uring/kbuf.c, branch v7.0-rc3</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>Convert 'alloc_obj' family to use the new default GFP_KERNEL argument</title>
<updated>2026-02-22T01:09:51+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-02-22T00:37:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43'/>
<id>bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43</id>
<content type='text'>
This was done entirely with mindless brute force, using

    git grep -l '\&lt;k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This was done entirely with mindless brute force, using

    git grep -l '\&lt;k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'kmalloc_obj-treewide-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux</title>
<updated>2026-02-21T19:02:58+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-02-21T19:02:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8934827db5403eae57d4537114a9ff88b0a8460f'/>
<id>8934827db5403eae57d4537114a9ff88b0a8460f</id>
<content type='text'>
Pull kmalloc_obj conversion from Kees Cook:
 "This does the tree-wide conversion to kmalloc_obj() and friends using
  coccinelle, with a subsequent small manual cleanup of whitespace
  alignment that coccinelle does not handle.

  This uncovered a clang bug in __builtin_counted_by_ref(), so the
  conversion is preceded by disabling that for current versions of
  clang.  The imminent clang 22.1 release has the fix.

  I've done allmodconfig build tests for x86_64, arm64, i386, and arm. I
  did defconfig builds for alpha, m68k, mips, parisc, powerpc, riscv,
  s390, sparc, sh, arc, csky, xtensa, hexagon, and openrisc"

* tag 'kmalloc_obj-treewide-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  kmalloc_obj: Clean up after treewide replacements
  treewide: Replace kmalloc with kmalloc_obj for non-scalar types
  compiler_types: Disable __builtin_counted_by_ref for Clang
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull kmalloc_obj conversion from Kees Cook:
 "This does the tree-wide conversion to kmalloc_obj() and friends using
  coccinelle, with a subsequent small manual cleanup of whitespace
  alignment that coccinelle does not handle.

  This uncovered a clang bug in __builtin_counted_by_ref(), so the
  conversion is preceded by disabling that for current versions of
  clang.  The imminent clang 22.1 release has the fix.

  I've done allmodconfig build tests for x86_64, arm64, i386, and arm. I
  did defconfig builds for alpha, m68k, mips, parisc, powerpc, riscv,
  s390, sparc, sh, arc, csky, xtensa, hexagon, and openrisc"

* tag 'kmalloc_obj-treewide-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  kmalloc_obj: Clean up after treewide replacements
  treewide: Replace kmalloc with kmalloc_obj for non-scalar types
  compiler_types: Disable __builtin_counted_by_ref for Clang
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: Replace kmalloc with kmalloc_obj for non-scalar types</title>
<updated>2026-02-21T09:02:28+00:00</updated>
<author>
<name>Kees Cook</name>
<email>kees@kernel.org</email>
</author>
<published>2026-02-21T07:49:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=69050f8d6d075dc01af7a5f2f550a8067510366f'/>
<id>69050f8d6d075dc01af7a5f2f550a8067510366f</id>
<content type='text'>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>io_uring: add IORING_OP_URING_CMD128 to opcode checks</title>
<updated>2026-02-19T14:25:39+00:00</updated>
<author>
<name>Caleb Sander Mateos</name>
<email>csander@purestorage.com</email>
</author>
<published>2026-02-19T01:35:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=42a6bd57ee9f930a72c26f863c72f666d6ed9ea5'/>
<id>42a6bd57ee9f930a72c26f863c72f666d6ed9ea5</id>
<content type='text'>
io_should_commit(), io_uring_classic_poll(), and io_do_iopoll() compare
struct io_kiocb's opcode against IORING_OP_URING_CMD to implement
special treatment for uring_cmds. The recently added opcode
IORING_OP_URING_CMD128 is meant to be equivalent to IORING_OP_URING_CMD,
so treat it the same way in these functions.

Fixes: 1cba30bf9fdd ("io_uring: add support for IORING_SETUP_SQE_MIXED")
Signed-off-by: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Reviewed-by: Anuj Gupta &lt;anuj20.g@samsung.com&gt;
Reviewed-by: Kanchan Joshi &lt;joshi.k@samsung.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
io_should_commit(), io_uring_classic_poll(), and io_do_iopoll() compare
struct io_kiocb's opcode against IORING_OP_URING_CMD to implement
special treatment for uring_cmds. The recently added opcode
IORING_OP_URING_CMD128 is meant to be equivalent to IORING_OP_URING_CMD,
so treat it the same way in these functions.

Fixes: 1cba30bf9fdd ("io_uring: add support for IORING_SETUP_SQE_MIXED")
Signed-off-by: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Reviewed-by: Anuj Gupta &lt;anuj20.g@samsung.com&gt;
Reviewed-by: Kanchan Joshi &lt;joshi.k@samsung.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>io_uring/kbuf: fix memory leak if io_buffer_add_list fails</title>
<updated>2026-02-05T18:13:16+00:00</updated>
<author>
<name>Jens Axboe</name>
<email>axboe@kernel.dk</email>
</author>
<published>2026-02-05T15:38:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=442ae406603a94f1a263654494f425302ceb0445'/>
<id>442ae406603a94f1a263654494f425302ceb0445</id>
<content type='text'>
io_register_pbuf_ring() ignores the return value of io_buffer_add_list(),
which can fail if xa_store() returns an error (e.g., -ENOMEM). When this
happens, the function returns 0 (success) to the caller, but the
io_buffer_list structure is neither added to the xarray nor freed.

In practice this requires failure injection to hit, hence not a real
issue. But it should get fixed up none the less.

Fixes: c7fb19428d67 ("io_uring: add support for ring mapped supplied buffers")
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
io_register_pbuf_ring() ignores the return value of io_buffer_add_list(),
which can fail if xa_store() returns an error (e.g., -ENOMEM). When this
happens, the function returns 0 (success) to the caller, but the
io_buffer_list structure is neither added to the xarray nor freed.

In practice this requires failure injection to hit, hence not a real
issue. But it should get fixed up none the less.

Fixes: c7fb19428d67 ("io_uring: add support for ring mapped supplied buffers")
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>io_uring/kbuf: use WRITE_ONCE() for userspace-shared buffer ring fields</title>
<updated>2025-12-05T16:52:02+00:00</updated>
<author>
<name>Joanne Koong</name>
<email>joannelkoong@gmail.com</email>
</author>
<published>2025-12-04T23:54:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a4c694bfc2455e82b7caf6045ca893d123e0ed11'/>
<id>a4c694bfc2455e82b7caf6045ca893d123e0ed11</id>
<content type='text'>
buf-&gt;addr and buf-&gt;len reside in memory shared with userspace. They
should be written with WRITE_ONCE() to guarantee atomic stores and
prevent tearing or other unsafe compiler optimizations.

Signed-off-by: Joanne Koong &lt;joannelkoong@gmail.com&gt;
Cc: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
buf-&gt;addr and buf-&gt;len reside in memory shared with userspace. They
should be written with WRITE_ONCE() to guarantee atomic stores and
prevent tearing or other unsafe compiler optimizations.

Signed-off-by: Joanne Koong &lt;joannelkoong@gmail.com&gt;
Cc: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>io_uring/kbuf: use READ_ONCE() for userspace-mapped memory</title>
<updated>2025-12-04T22:46:23+00:00</updated>
<author>
<name>Caleb Sander Mateos</name>
<email>csander@purestorage.com</email>
</author>
<published>2025-12-04T22:43:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=78385c7299f7514697d196b3233a91bd5e485591'/>
<id>78385c7299f7514697d196b3233a91bd5e485591</id>
<content type='text'>
The struct io_uring_buf elements in a buffer ring are in a memory region
accessible from userspace. A malicious/buggy userspace program could
therefore write to them at any time, so they should be accessed with
READ_ONCE() in the kernel. Commit 98b6fa62c84f ("io_uring/kbuf: always
use READ_ONCE() to read ring provided buffer lengths") already switched
the reads of the len field to READ_ONCE(). Do the same for bid and addr.

Signed-off-by: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Fixes: c7fb19428d67 ("io_uring: add support for ring mapped supplied buffers")
Cc: Joanne Koong &lt;joannelkoong@gmail.com&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 struct io_uring_buf elements in a buffer ring are in a memory region
accessible from userspace. A malicious/buggy userspace program could
therefore write to them at any time, so they should be accessed with
READ_ONCE() in the kernel. Commit 98b6fa62c84f ("io_uring/kbuf: always
use READ_ONCE() to read ring provided buffer lengths") already switched
the reads of the len field to READ_ONCE(). Do the same for bid and addr.

Signed-off-by: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Fixes: c7fb19428d67 ("io_uring: add support for ring mapped supplied buffers")
Cc: Joanne Koong &lt;joannelkoong@gmail.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'io_uring-6.18' into for-6.19/io_uring</title>
<updated>2025-11-13T14:26:37+00:00</updated>
<author>
<name>Jens Axboe</name>
<email>axboe@kernel.dk</email>
</author>
<published>2025-11-13T14:26:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ecb8490b2f4393550a2651f547b7fa67490c4881'/>
<id>ecb8490b2f4393550a2651f547b7fa67490c4881</id>
<content type='text'>
Merge 6.18-rc io_uring fixes, as certain coming changes depend on some
of these.

* io_uring-6.18:
  io_uring/rsrc: don't use blk_rq_nr_phys_segments() as number of bvecs
  io_uring/query: return number of available queries
  io_uring/rw: ensure allocated iovec gets cleared for early failure
  io_uring: fix regbuf vector size truncation
  io_uring: fix types for region size calulation
  io_uring/zcrx: remove sync refill uapi
  io_uring: fix buffer auto-commit for multishot uring_cmd
  io_uring: correct __must_hold annotation in io_install_fixed_file
  io_uring zcrx: add MAINTAINERS entry
  io_uring: Fix code indentation error
  io_uring/sqpoll: be smarter on when to update the stime usage
  io_uring/sqpoll: switch away from getrusage() for CPU accounting
  io_uring: fix incorrect unlikely() usage in io_waitid_prep()

Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge 6.18-rc io_uring fixes, as certain coming changes depend on some
of these.

* io_uring-6.18:
  io_uring/rsrc: don't use blk_rq_nr_phys_segments() as number of bvecs
  io_uring/query: return number of available queries
  io_uring/rw: ensure allocated iovec gets cleared for early failure
  io_uring: fix regbuf vector size truncation
  io_uring: fix types for region size calulation
  io_uring/zcrx: remove sync refill uapi
  io_uring: fix buffer auto-commit for multishot uring_cmd
  io_uring: correct __must_hold annotation in io_install_fixed_file
  io_uring zcrx: add MAINTAINERS entry
  io_uring: Fix code indentation error
  io_uring/sqpoll: be smarter on when to update the stime usage
  io_uring/sqpoll: switch away from getrusage() for CPU accounting
  io_uring: fix incorrect unlikely() usage in io_waitid_prep()

Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>io_uring/memmap: refactor io_free_region() to take user_struct param</title>
<updated>2025-11-06T23:23:21+00:00</updated>
<author>
<name>David Wei</name>
<email>dw@davidwei.uk</email>
</author>
<published>2025-11-04T22:44:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1fa7a34131110e3c41a13b19127da132dea32dcd'/>
<id>1fa7a34131110e3c41a13b19127da132dea32dcd</id>
<content type='text'>
Refactor io_free_region() to take user_struct directly, instead of
accessing it from the ring ctx.

Signed-off-by: David Wei &lt;dw@davidwei.uk&gt;
Reviewed-by: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Refactor io_free_region() to take user_struct directly, instead of
accessing it from the ring ctx.

Signed-off-by: David Wei &lt;dw@davidwei.uk&gt;
Reviewed-by: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>io_uring: fix buffer auto-commit for multishot uring_cmd</title>
<updated>2025-10-24T01:41:31+00:00</updated>
<author>
<name>Ming Lei</name>
<email>ming.lei@redhat.com</email>
</author>
<published>2025-10-24T01:34:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6f1cbf6d6fd13fc169dde14e865897924cdc4bbd'/>
<id>6f1cbf6d6fd13fc169dde14e865897924cdc4bbd</id>
<content type='text'>
Commit 620a50c92700 ("io_uring: uring_cmd: add multishot support") added
multishot uring_cmd support with explicit buffer upfront commit via
io_uring_mshot_cmd_post_cqe(). However, the buffer selection path in
io_ring_buffer_select() was auto-committing buffers for non-pollable files,
which conflicts with uring_cmd's explicit upfront commit model.

This way consumes the whole selected buffer immediately, and causes
failure on the following buffer selection.

Fix this by checking uring_cmd to identify operations that handle buffer
commit explicitly, and skip auto-commit for these operations.

Cc: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Fixes: 620a50c92700 ("io_uring: uring_cmd: add multishot support")
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 620a50c92700 ("io_uring: uring_cmd: add multishot support") added
multishot uring_cmd support with explicit buffer upfront commit via
io_uring_mshot_cmd_post_cqe(). However, the buffer selection path in
io_ring_buffer_select() was auto-committing buffers for non-pollable files,
which conflicts with uring_cmd's explicit upfront commit model.

This way consumes the whole selected buffer immediately, and causes
failure on the following buffer selection.

Fix this by checking uring_cmd to identify operations that handle buffer
commit explicitly, and skip auto-commit for these operations.

Cc: Caleb Sander Mateos &lt;csander@purestorage.com&gt;
Fixes: 620a50c92700 ("io_uring: uring_cmd: add multishot support")
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
</feed>
