<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/android, branch v6.18-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>rust_binder: add Rust Binder driver</title>
<updated>2025-09-19T07:40:46+00:00</updated>
<author>
<name>Alice Ryhl</name>
<email>aliceryhl@google.com</email>
</author>
<published>2025-09-19T06:42:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=eafedbc7c050c44744fbdf80bdf3315e860b7513'/>
<id>eafedbc7c050c44744fbdf80bdf3315e860b7513</id>
<content type='text'>
We're generally not proponents of rewrites (nasty uncomfortable things
that make you late for dinner!). So why rewrite Binder?

Binder has been evolving over the past 15+ years to meet the evolving
needs of Android. Its responsibilities, expectations, and complexity
have grown considerably during that time. While we expect Binder to
continue to evolve along with Android, there are a number of factors
that currently constrain our ability to develop/maintain it. Briefly
those are:

1. Complexity: Binder is at the intersection of everything in Android and
   fulfills many responsibilities beyond IPC. It has become many things
   to many people, and due to its many features and their interactions
   with each other, its complexity is quite high. In just 6kLOC it must
   deliver transactions to the right threads. It must correctly parse
   and translate the contents of transactions, which can contain several
   objects of different types (e.g., pointers, fds) that can interact
   with each other. It controls the size of thread pools in userspace,
   and ensures that transactions are assigned to threads in ways that
   avoid deadlocks where the threadpool has run out of threads. It must
   track refcounts of objects that are shared by several processes by
   forwarding refcount changes between the processes correctly.  It must
   handle numerous error scenarios and it combines/nests 13 different
   locks, 7 reference counters, and atomic variables. Finally, It must
   do all of this as fast and efficiently as possible. Minor performance
   regressions can cause a noticeably degraded user experience.

2. Things to improve: Thousand-line functions [1], error-prone error
   handling [2], and confusing structure can occur as a code base grows
   organically. After more than a decade of development, this codebase
   could use an overhaul.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/android/binder.c?h=v6.5#n2896
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/android/binder.c?h=v6.5#n3658

3. Security critical: Binder is a critical part of Android's sandboxing
   strategy. Even Android's most de-privileged sandboxes (e.g. the
   Chrome renderer, or SW Codec) have direct access to Binder. More than
   just about any other component, it's important that Binder provide
   robust security, and itself be robust against security
   vulnerabilities.

It's #1 (high complexity) that has made continuing to evolve Binder and
resolving #2 (tech debt) exceptionally difficult without causing #3
(security issues). For Binder to continue to meet Android's needs, we
need better ways to manage (and reduce!) complexity without increasing
the risk.

The biggest change is obviously the choice of programming language. We
decided to use Rust because it directly addresses a number of the
challenges within Binder that we have faced during the last years. It
prevents mistakes with ref counting, locking, bounds checking, and also
does a lot to reduce the complexity of error handling. Additionally,
we've been able to use the more expressive type system to encode the
ownership semantics of the various structs and pointers, which takes the
complexity of managing object lifetimes out of the hands of the
programmer, reducing the risk of use-after-frees and similar problems.

Rust has many different pointer types that it uses to encode ownership
semantics into the type system, and this is probably one of the most
important aspects of how it helps in Binder. The Binder driver has a lot
of different objects that have complex ownership semantics; some
pointers own a refcount, some pointers have exclusive ownership, and
some pointers just reference the object and it is kept alive in some
other manner. With Rust, we can use a different pointer type for each
kind of pointer, which enables the compiler to enforce that the
ownership semantics are implemented correctly.

Another useful feature is Rust's error handling. Rust allows for more
simplified error handling with features such as destructors, and you get
compilation failures if errors are not properly handled. This means that
even though Rust requires you to spend more lines of code than C on
things such as writing down invariants that are left implicit in C, the
Rust driver is still slightly smaller than C binder: Rust is 5.5kLOC and
C is 5.8kLOC. (These numbers are excluding blank lines, comments,
binderfs, and any debugging facilities in C that are not yet implemented
in the Rust driver. The numbers include abstractions in rust/kernel/
that are unlikely to be used by other drivers than Binder.)

Although this rewrite completely rethinks how the code is structured and
how assumptions are enforced, we do not fundamentally change *how* the
driver does the things it does. A lot of careful thought has gone into
the existing design. The rewrite is aimed rather at improving code
health, structure, readability, robustness, security, maintainability
and extensibility. We also include more inline documentation, and
improve how assumptions in the code are enforced. Furthermore, all
unsafe code is annotated with a SAFETY comment that explains why it is
correct.

We have left the binderfs filesystem component in C. Rewriting it in
Rust would be a large amount of work and requires a lot of bindings to
the file system interfaces. Binderfs has not historically had the same
challenges with security and complexity, so rewriting binderfs seems to
have lower value than the rest of Binder.

Correctness and feature parity
------------------------------

Rust binder passes all tests that validate the correctness of Binder in
the Android Open Source Project. We can boot a device, and run a variety
of apps and functionality without issues. We have performed this both on
the Cuttlefish Android emulator device, and on a Pixel 6 Pro.

As for feature parity, Rust binder currently implements all features
that C binder supports, with the exception of some debugging facilities.
The missing debugging facilities will be added before we submit the Rust
implementation upstream.

Tracepoints
-----------

I did not include all of the tracepoints as I felt that the mechansim
for making C access fields of Rust structs should be discussed on list
separately. I also did not include the support for building Rust Binder
as a module since that requires exporting a bunch of additional symbols
on the C side.

Original RFC Link with old benchmark numbers:
	https://lore.kernel.org/r/20231101-rust-binder-v1-0-08ba9197f637@google.com

Co-developed-by: Wedson Almeida Filho &lt;wedsonaf@gmail.com&gt;
Signed-off-by: Wedson Almeida Filho &lt;wedsonaf@gmail.com&gt;
Co-developed-by: Matt Gilbride &lt;mattgilbride@google.com&gt;
Signed-off-by: Matt Gilbride &lt;mattgilbride@google.com&gt;
Acked-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.com&gt;
Signed-off-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Link: https://lore.kernel.org/r/20250919-rust-binder-v2-1-a384b09f28dd@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We're generally not proponents of rewrites (nasty uncomfortable things
that make you late for dinner!). So why rewrite Binder?

Binder has been evolving over the past 15+ years to meet the evolving
needs of Android. Its responsibilities, expectations, and complexity
have grown considerably during that time. While we expect Binder to
continue to evolve along with Android, there are a number of factors
that currently constrain our ability to develop/maintain it. Briefly
those are:

1. Complexity: Binder is at the intersection of everything in Android and
   fulfills many responsibilities beyond IPC. It has become many things
   to many people, and due to its many features and their interactions
   with each other, its complexity is quite high. In just 6kLOC it must
   deliver transactions to the right threads. It must correctly parse
   and translate the contents of transactions, which can contain several
   objects of different types (e.g., pointers, fds) that can interact
   with each other. It controls the size of thread pools in userspace,
   and ensures that transactions are assigned to threads in ways that
   avoid deadlocks where the threadpool has run out of threads. It must
   track refcounts of objects that are shared by several processes by
   forwarding refcount changes between the processes correctly.  It must
   handle numerous error scenarios and it combines/nests 13 different
   locks, 7 reference counters, and atomic variables. Finally, It must
   do all of this as fast and efficiently as possible. Minor performance
   regressions can cause a noticeably degraded user experience.

2. Things to improve: Thousand-line functions [1], error-prone error
   handling [2], and confusing structure can occur as a code base grows
   organically. After more than a decade of development, this codebase
   could use an overhaul.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/android/binder.c?h=v6.5#n2896
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/android/binder.c?h=v6.5#n3658

3. Security critical: Binder is a critical part of Android's sandboxing
   strategy. Even Android's most de-privileged sandboxes (e.g. the
   Chrome renderer, or SW Codec) have direct access to Binder. More than
   just about any other component, it's important that Binder provide
   robust security, and itself be robust against security
   vulnerabilities.

It's #1 (high complexity) that has made continuing to evolve Binder and
resolving #2 (tech debt) exceptionally difficult without causing #3
(security issues). For Binder to continue to meet Android's needs, we
need better ways to manage (and reduce!) complexity without increasing
the risk.

The biggest change is obviously the choice of programming language. We
decided to use Rust because it directly addresses a number of the
challenges within Binder that we have faced during the last years. It
prevents mistakes with ref counting, locking, bounds checking, and also
does a lot to reduce the complexity of error handling. Additionally,
we've been able to use the more expressive type system to encode the
ownership semantics of the various structs and pointers, which takes the
complexity of managing object lifetimes out of the hands of the
programmer, reducing the risk of use-after-frees and similar problems.

Rust has many different pointer types that it uses to encode ownership
semantics into the type system, and this is probably one of the most
important aspects of how it helps in Binder. The Binder driver has a lot
of different objects that have complex ownership semantics; some
pointers own a refcount, some pointers have exclusive ownership, and
some pointers just reference the object and it is kept alive in some
other manner. With Rust, we can use a different pointer type for each
kind of pointer, which enables the compiler to enforce that the
ownership semantics are implemented correctly.

Another useful feature is Rust's error handling. Rust allows for more
simplified error handling with features such as destructors, and you get
compilation failures if errors are not properly handled. This means that
even though Rust requires you to spend more lines of code than C on
things such as writing down invariants that are left implicit in C, the
Rust driver is still slightly smaller than C binder: Rust is 5.5kLOC and
C is 5.8kLOC. (These numbers are excluding blank lines, comments,
binderfs, and any debugging facilities in C that are not yet implemented
in the Rust driver. The numbers include abstractions in rust/kernel/
that are unlikely to be used by other drivers than Binder.)

Although this rewrite completely rethinks how the code is structured and
how assumptions are enforced, we do not fundamentally change *how* the
driver does the things it does. A lot of careful thought has gone into
the existing design. The rewrite is aimed rather at improving code
health, structure, readability, robustness, security, maintainability
and extensibility. We also include more inline documentation, and
improve how assumptions in the code are enforced. Furthermore, all
unsafe code is annotated with a SAFETY comment that explains why it is
correct.

We have left the binderfs filesystem component in C. Rewriting it in
Rust would be a large amount of work and requires a lot of bindings to
the file system interfaces. Binderfs has not historically had the same
challenges with security and complexity, so rewriting binderfs seems to
have lower value than the rest of Binder.

Correctness and feature parity
------------------------------

Rust binder passes all tests that validate the correctness of Binder in
the Android Open Source Project. We can boot a device, and run a variety
of apps and functionality without issues. We have performed this both on
the Cuttlefish Android emulator device, and on a Pixel 6 Pro.

As for feature parity, Rust binder currently implements all features
that C binder supports, with the exception of some debugging facilities.
The missing debugging facilities will be added before we submit the Rust
implementation upstream.

Tracepoints
-----------

I did not include all of the tracepoints as I felt that the mechansim
for making C access fields of Rust structs should be discussed on list
separately. I also did not include the support for building Rust Binder
as a module since that requires exporting a bunch of additional symbols
on the C side.

Original RFC Link with old benchmark numbers:
	https://lore.kernel.org/r/20231101-rust-binder-v1-0-08ba9197f637@google.com

Co-developed-by: Wedson Almeida Filho &lt;wedsonaf@gmail.com&gt;
Signed-off-by: Wedson Almeida Filho &lt;wedsonaf@gmail.com&gt;
Co-developed-by: Matt Gilbride &lt;mattgilbride@google.com&gt;
Signed-off-by: Matt Gilbride &lt;mattgilbride@google.com&gt;
Acked-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.com&gt;
Signed-off-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Link: https://lore.kernel.org/r/20250919-rust-binder-v2-1-a384b09f28dd@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: fix double-free in dbitmap</title>
<updated>2025-09-18T15:20:00+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2025-09-15T22:12:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3ebcd3460cad351f198c39c6edb4af519a0ed934'/>
<id>3ebcd3460cad351f198c39c6edb4af519a0ed934</id>
<content type='text'>
A process might fail to allocate a new bitmap when trying to expand its
proc-&gt;dmap. In that case, dbitmap_grow() fails and frees the old bitmap
via dbitmap_free(). However, the driver calls dbitmap_free() again when
the same process terminates, leading to a double-free error:

  ==================================================================
  BUG: KASAN: double-free in binder_proc_dec_tmpref+0x2e0/0x55c
  Free of addr ffff00000b7c1420 by task kworker/9:1/209

  CPU: 9 UID: 0 PID: 209 Comm: kworker/9:1 Not tainted 6.17.0-rc6-dirty #5 PREEMPT
  Hardware name: linux,dummy-virt (DT)
  Workqueue: events binder_deferred_func
  Call trace:
   kfree+0x164/0x31c
   binder_proc_dec_tmpref+0x2e0/0x55c
   binder_deferred_func+0xc24/0x1120
   process_one_work+0x520/0xba4
  [...]

  Allocated by task 448:
   __kmalloc_noprof+0x178/0x3c0
   bitmap_zalloc+0x24/0x30
   binder_open+0x14c/0xc10
  [...]

  Freed by task 449:
   kfree+0x184/0x31c
   binder_inc_ref_for_node+0xb44/0xe44
   binder_transaction+0x29b4/0x7fbc
   binder_thread_write+0x1708/0x442c
   binder_ioctl+0x1b50/0x2900
  [...]
  ==================================================================

Fix this issue by marking proc-&gt;map NULL in dbitmap_free().

Cc: stable@vger.kernel.org
Fixes: 15d9da3f818c ("binder: use bitmap for faster descriptor lookup")
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Reviewed-by: Tiffany Yang &lt;ynaffit@google.com&gt;
Link: https://lore.kernel.org/r/20250915221248.3470154-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A process might fail to allocate a new bitmap when trying to expand its
proc-&gt;dmap. In that case, dbitmap_grow() fails and frees the old bitmap
via dbitmap_free(). However, the driver calls dbitmap_free() again when
the same process terminates, leading to a double-free error:

  ==================================================================
  BUG: KASAN: double-free in binder_proc_dec_tmpref+0x2e0/0x55c
  Free of addr ffff00000b7c1420 by task kworker/9:1/209

  CPU: 9 UID: 0 PID: 209 Comm: kworker/9:1 Not tainted 6.17.0-rc6-dirty #5 PREEMPT
  Hardware name: linux,dummy-virt (DT)
  Workqueue: events binder_deferred_func
  Call trace:
   kfree+0x164/0x31c
   binder_proc_dec_tmpref+0x2e0/0x55c
   binder_deferred_func+0xc24/0x1120
   process_one_work+0x520/0xba4
  [...]

  Allocated by task 448:
   __kmalloc_noprof+0x178/0x3c0
   bitmap_zalloc+0x24/0x30
   binder_open+0x14c/0xc10
  [...]

  Freed by task 449:
   kfree+0x184/0x31c
   binder_inc_ref_for_node+0xb44/0xe44
   binder_transaction+0x29b4/0x7fbc
   binder_thread_write+0x1708/0x442c
   binder_ioctl+0x1b50/0x2900
  [...]
  ==================================================================

Fix this issue by marking proc-&gt;map NULL in dbitmap_free().

Cc: stable@vger.kernel.org
Fixes: 15d9da3f818c ("binder: use bitmap for faster descriptor lookup")
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Reviewed-by: Tiffany Yang &lt;ynaffit@google.com&gt;
Link: https://lore.kernel.org/r/20250915221248.3470154-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: add tracepoint for netlink reports</title>
<updated>2025-08-19T10:53:02+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2025-07-27T18:29:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8a61a53b07f23ff12330086b293b6b492d35b8a0'/>
<id>8a61a53b07f23ff12330086b293b6b492d35b8a0</id>
<content type='text'>
Add a tracepoint to capture the same details that are being sent through
the generic netlink interface during transaction failures. This provides
a useful debugging tool to observe the events independently from the
netlink listeners.

Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-6-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add a tracepoint to capture the same details that are being sent through
the generic netlink interface during transaction failures. This provides
a useful debugging tool to observe the events independently from the
netlink listeners.

Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-6-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: add transaction_report feature entry</title>
<updated>2025-08-19T10:53:01+00:00</updated>
<author>
<name>Li Li</name>
<email>dualli@google.com</email>
</author>
<published>2025-07-27T18:29:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f37b55ded8ed35424ebb91a4d012527071e1f601'/>
<id>f37b55ded8ed35424ebb91a4d012527071e1f601</id>
<content type='text'>
Add "transaction_report" to the binderfs feature list, to help userspace
determine if the "BINDER_CMD_REPORT" generic netlink api is supported by
the binder driver.

Signed-off-by: Li Li &lt;dualli@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-5-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add "transaction_report" to the binderfs feature list, to help userspace
determine if the "BINDER_CMD_REPORT" generic netlink api is supported by
the binder driver.

Signed-off-by: Li Li &lt;dualli@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-5-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: introduce transaction reports via netlink</title>
<updated>2025-08-19T10:53:01+00:00</updated>
<author>
<name>Li Li</name>
<email>dualli@google.com</email>
</author>
<published>2025-07-27T18:29:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=63740349eba78f242bcbf60d5244d7f2b2600853'/>
<id>63740349eba78f242bcbf60d5244d7f2b2600853</id>
<content type='text'>
Introduce a generic netlink multicast event to report binder transaction
failures to userspace. This allows subscribers to monitor these events
and take appropriate actions, such as stopping a misbehaving application
that is spamming a service with huge amount of transactions.

The multicast event contains full details of the failed transactions,
including the sender/target PIDs, payload size and specific error code.
This interface is defined using a YAML spec, from which the UAPI and
kernel headers and source are auto-generated.

Signed-off-by: Li Li &lt;dualli@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-4-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Introduce a generic netlink multicast event to report binder transaction
failures to userspace. This allows subscribers to monitor these events
and take appropriate actions, such as stopping a misbehaving application
that is spamming a service with huge amount of transactions.

The multicast event contains full details of the failed transactions,
including the sender/target PIDs, payload size and specific error code.
This interface is defined using a YAML spec, from which the UAPI and
kernel headers and source are auto-generated.

Signed-off-by: Li Li &lt;dualli@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-4-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: add t-&gt;is_async and t-&gt;is_reply</title>
<updated>2025-08-19T10:53:01+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2025-07-27T18:29:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5cd0645b43c7edf55518272a6c69230a5c631729'/>
<id>5cd0645b43c7edf55518272a6c69230a5c631729</id>
<content type='text'>
Replace the t-&gt;need_reply flag with the more descriptive t-&gt;is_async and
and t-&gt;is_reply flags. The 'need_reply' flag was only used for debugging
purposes and the new flags can be used to distinguish between the type
of transactions too: sync, async and reply.

For now, only update the logging in print_binder_transaction_ilocked().
However, the new flags can be used in the future to replace the current
patterns and improve readability. e.g.:

  - if (!reply &amp;&amp; !(tr-&gt;flags &amp; TF_ONE_WAY))
  + if (t-&gt;is_async)

This patch is in preparation for binder's generic netlink implementation
and no functional changes are intended.

Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-3-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Replace the t-&gt;need_reply flag with the more descriptive t-&gt;is_async and
and t-&gt;is_reply flags. The 'need_reply' flag was only used for debugging
purposes and the new flags can be used to distinguish between the type
of transactions too: sync, async and reply.

For now, only update the logging in print_binder_transaction_ilocked().
However, the new flags can be used in the future to replace the current
patterns and improve readability. e.g.:

  - if (!reply &amp;&amp; !(tr-&gt;flags &amp; TF_ONE_WAY))
  + if (t-&gt;is_async)

This patch is in preparation for binder's generic netlink implementation
and no functional changes are intended.

Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-3-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: pre-allocate binder_transaction</title>
<updated>2025-08-19T10:53:01+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2025-07-27T18:29:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4afc5bf0a1849f0ed3ea1d9fd9d0e79b23a67f96'/>
<id>4afc5bf0a1849f0ed3ea1d9fd9d0e79b23a67f96</id>
<content type='text'>
Move the allocation of 'struct binder_transaction' to the beginning of
the binder_transaction() function, along with the initialization of all
the members that are known at that time. This minor refactoring helps to
consolidate the usage of transaction information at later points.

This patch is in preparation for binder's generic netlink implementation
and no functional changes are intended.

Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-2-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move the allocation of 'struct binder_transaction' to the beginning of
the binder_transaction() function, along with the initialization of all
the members that are known at that time. This minor refactoring helps to
consolidate the usage of transaction information at later points.

This patch is in preparation for binder's generic netlink implementation
and no functional changes are intended.

Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250727182932.2499194-2-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: remove MODULE_LICENSE()</title>
<updated>2025-08-18T09:49:19+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2025-08-17T13:50:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4d2604833e8ea79e77de98aa97a94b94a9733962'/>
<id>4d2604833e8ea79e77de98aa97a94b94a9733962</id>
<content type='text'>
The MODULE_LICENSE() macro is intended for drivers that can be built as
loadable modules. The binder driver is always built-in, using this macro
here is unnecessary and potentially confusing. Remove it.

Cc: Salvatore Bonaccorso &lt;carnil@debian.org&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250817135034.3692902-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The MODULE_LICENSE() macro is intended for drivers that can be built as
loadable modules. The binder driver is always built-in, using this macro
here is unnecessary and potentially confusing. Remove it.

Cc: Salvatore Bonaccorso &lt;carnil@debian.org&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20250817135034.3692902-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'char-misc-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc</title>
<updated>2025-07-29T16:52:01+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-07-29T16:52:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0d5ec7919f3747193f051036b2301734a4b5e1d6'/>
<id>0d5ec7919f3747193f051036b2301734a4b5e1d6</id>
<content type='text'>
Pull char / misc / IIO / other driver updates from Greg KH:
 "Here is the big set of char/misc/iio and other smaller driver
  subsystems for 6.17-rc1. It's a big set this time around, with the
  huge majority being in the iio subsystem with new drivers and dts
  files being added there.

  Highlights include:
   - IIO driver updates, additions, and changes making more code const
     and cleaning up some init logic
   - bus_type constant conversion changes
   - misc device test functions added
   - rust miscdevice minor fixup
   - unused function removals for some drivers
   - mei driver updates
   - mhi driver updates
   - interconnect driver updates
   - Android binder updates and test infrastructure added
   - small cdx driver updates
   - small comedi fixes
   - small nvmem driver updates
   - small pps driver updates
   - some acrn virt driver fixes for printk messages
   - other small driver updates

  All of these have been in linux-next with no reported issues"

* tag 'char-misc-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
  binder: Use seq_buf in binder_alloc kunit tests
  binder: Add copyright notice to new kunit files
  misc: ti_fpc202: Switch to of_fwnode_handle()
  bus: moxtet: Use dev_fwnode()
  pc104: move PC104 option to drivers/Kconfig
  drivers: virt: acrn: Don't use %pK through printk
  comedi: fix race between polling and detaching
  interconnect: qcom: Add Milos interconnect provider driver
  dt-bindings: interconnect: document the RPMh Network-On-Chip Interconnect in Qualcomm Milos SoC
  mei: more prints with client prefix
  mei: bus: use cldev in prints
  bus: mhi: host: pci_generic: Add Telit FN990B40 modem support
  bus: mhi: host: Detect events pointing to unexpected TREs
  bus: mhi: host: pci_generic: Add Foxconn T99W696 modem
  bus: mhi: host: Use str_true_false() helper
  bus: mhi: host: pci_generic: Add support for EM929x and set MRU to 32768 for better performance.
  bus: mhi: host: Fix endianness of BHI vector table
  bus: mhi: host: pci_generic: Disable runtime PM for QDU100
  bus: mhi: host: pci_generic: Fix the modem name of Foxconn T99W640
  dt-bindings: interconnect: qcom,msm8998-bwmon: Allow 'nonposted-mmio'
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull char / misc / IIO / other driver updates from Greg KH:
 "Here is the big set of char/misc/iio and other smaller driver
  subsystems for 6.17-rc1. It's a big set this time around, with the
  huge majority being in the iio subsystem with new drivers and dts
  files being added there.

  Highlights include:
   - IIO driver updates, additions, and changes making more code const
     and cleaning up some init logic
   - bus_type constant conversion changes
   - misc device test functions added
   - rust miscdevice minor fixup
   - unused function removals for some drivers
   - mei driver updates
   - mhi driver updates
   - interconnect driver updates
   - Android binder updates and test infrastructure added
   - small cdx driver updates
   - small comedi fixes
   - small nvmem driver updates
   - small pps driver updates
   - some acrn virt driver fixes for printk messages
   - other small driver updates

  All of these have been in linux-next with no reported issues"

* tag 'char-misc-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
  binder: Use seq_buf in binder_alloc kunit tests
  binder: Add copyright notice to new kunit files
  misc: ti_fpc202: Switch to of_fwnode_handle()
  bus: moxtet: Use dev_fwnode()
  pc104: move PC104 option to drivers/Kconfig
  drivers: virt: acrn: Don't use %pK through printk
  comedi: fix race between polling and detaching
  interconnect: qcom: Add Milos interconnect provider driver
  dt-bindings: interconnect: document the RPMh Network-On-Chip Interconnect in Qualcomm Milos SoC
  mei: more prints with client prefix
  mei: bus: use cldev in prints
  bus: mhi: host: pci_generic: Add Telit FN990B40 modem support
  bus: mhi: host: Detect events pointing to unexpected TREs
  bus: mhi: host: pci_generic: Add Foxconn T99W696 modem
  bus: mhi: host: Use str_true_false() helper
  bus: mhi: host: pci_generic: Add support for EM929x and set MRU to 32768 for better performance.
  bus: mhi: host: Fix endianness of BHI vector table
  bus: mhi: host: pci_generic: Disable runtime PM for QDU100
  bus: mhi: host: pci_generic: Fix the modem name of Foxconn T99W640
  dt-bindings: interconnect: qcom,msm8998-bwmon: Allow 'nonposted-mmio'
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2025-07-28T17:32:20+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-07-28T17:32:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2d9c1336edc7d8f8e058822e02c0ce4d126a298e'/>
<id>2d9c1336edc7d8f8e058822e02c0ce4d126a298e</id>
<content type='text'>
Pull misc VFS updates from Al Viro:
 "VFS-related cleanups in various places (mostly of the "that really
  can't happen" or "there's a better way to do it" variety)"

* tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  gpib: use file_inode()
  binder_ioctl_write_read(): simplify control flow a bit
  secretmem: move setting O_LARGEFILE and bumping users' count to the place where we create the file
  apparmor: file never has NULL f_path.mnt
  landlock: opened file never has a negative dentry
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull misc VFS updates from Al Viro:
 "VFS-related cleanups in various places (mostly of the "that really
  can't happen" or "there's a better way to do it" variety)"

* tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  gpib: use file_inode()
  binder_ioctl_write_read(): simplify control flow a bit
  secretmem: move setting O_LARGEFILE and bumping users' count to the place where we create the file
  apparmor: file never has NULL f_path.mnt
  landlock: opened file never has a negative dentry
</pre>
</div>
</content>
</entry>
</feed>
