<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/include/linux/sysfs.h, branch v7.1-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core</title>
<updated>2026-04-14T02:03:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-14T02:03:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4793dae01f47754e288cdbb3a22581cac2317f2b'/>
<id>4793dae01f47754e288cdbb3a22581cac2317f2b</id>
<content type='text'>
Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Fix NULL pointer dereference in debugfs_create_str()
   - Fix misplaced EXPORT_SYMBOL_GPL for debugfs_create_str()
   - Fix soundwire debugfs NULL pointer dereference from uninitialized
     firmware_file

  device property:
   - Make fwnode flags modifications thread safe; widen the field to
     unsigned long and use set_bit() / clear_bit() based accessors
   - Document how to check for the property presence

  devres:
   - Separate struct devres_node from its "subclasses" (struct devres,
     struct devres_group); give struct devres_node its own release and
     free callbacks for per-type dispatch
   - Introduce struct devres_action for devres actions, avoiding the
     ARCH_DMA_MINALIGN alignment overhead of struct devres
   - Export struct devres_node and its init/add/remove/dbginfo
     primitives for use by Rust Devres&lt;T&gt;
   - Fix missing node debug info in devm_krealloc()
   - Use guard(spinlock_irqsave) where applicable; consolidate unlock
     paths in devres_release_group()

  driver_override:
   - Convert PCI, WMI, vdpa, s390/cio, s390/ap, and fsl-mc to the
     generic driver_override infrastructure, replacing per-bus
     driver_override strings, sysfs attributes, and match logic; fixes a
     potential UAF from unsynchronized access to driver_override in bus
     match() callbacks
   - Simplify __device_set_driver_override() logic

  kernfs:
   - Send IN_DELETE_SELF and IN_IGNORED inotify events on kernfs file
     and directory removal
   - Add corresponding selftests for memcg

  platform:
   - Allow attaching software nodes when creating platform devices via a
     new 'swnode' field in struct platform_device_info
   - Add kerneldoc for struct platform_device_info

  software node:
   - Move software node initialization from postcore_initcall() to
     driver_init(), making it available early in the boot process
   - Move kernel_kobj initialization (ksysfs_init) earlier to support
     the above
   - Remove software_node_exit(); dead code in a built-in unit

  SoC:
   - Introduce of_machine_read_compatible() and of_machine_read_model()
     OF helpers and export soc_attr_read_machine() to replace direct
     accesses to of_root from SoC drivers; also enables
     CONFIG_COMPILE_TEST coverage for these drivers

  sysfs:
   - Constify attribute group array pointers to
     'const struct attribute_group *const *' in sysfs functions,
     device_add_groups() / device_remove_groups(), and struct class

  Rust:
   - Devres:
      - Embed struct devres_node directly in Devres&lt;T&gt; instead of going
        through devm_add_action(), avoiding the extra allocation and the
        unnecessary ARCH_DMA_MINALIGN alignment

   - I/O:
      - Turn IoCapable from a marker trait into a functional trait
        carrying the raw I/O accessor implementation (io_read /
        io_write), providing working defaults for the per-type Io
        methods
      - Add RelaxedMmio wrapper type, making relaxed accessors usable in
        code generic over the Io trait
      - Remove overloaded per-type Io methods and per-backend macros
        from Mmio and PCI ConfigSpace

   - I/O (Register):
      - Add IoLoc trait and generic read/write/update methods to the Io
        trait, making I/O operations parameterizable by typed locations
      - Add register! macro for defining hardware register types with
        typed bitfield accessors backed by Bounded values; supports
        direct, relative, and array register addressing
      - Add write_reg() / try_write_reg() and LocatedRegister trait
      - Update PCI sample driver to demonstrate the register! macro

         Example:

         ```
             register! {
                 /// UART control register.
                 CTRL(u32) @ 0x18 {
                     /// Receiver enable.
                     19:19   rx_enable =&gt; bool;
                     /// Parity configuration.
                     14:13   parity ?=&gt; Parity;
                 }

                 /// FIFO watermark and counter register.
                 WATER(u32) @ 0x2c {
                     /// Number of datawords in the receive FIFO.
                     26:24   rx_count;
                     /// RX interrupt threshold.
                     17:16   rx_water;
                 }
             }

             impl WATER {
                 fn rx_above_watermark(&amp;self) -&gt; bool {
                     self.rx_count() &gt; self.rx_water()
                 }
             }

             fn init(bar: &amp;pci::Bar&lt;BAR0_SIZE&gt;) {
                 let water = WATER::zeroed()
                     .with_const_rx_water::&lt;1&gt;(); // &gt; 3 would not compile
                 bar.write_reg(water);

                 let ctrl = CTRL::zeroed()
                     .with_parity(Parity::Even)
                     .with_rx_enable(true);
                 bar.write_reg(ctrl);
             }

             fn handle_rx(bar: &amp;pci::Bar&lt;BAR0_SIZE&gt;) {
                 if bar.read(WATER).rx_above_watermark() {
                     // drain the FIFO
                 }
             }

             fn set_parity(bar: &amp;pci::Bar&lt;BAR0_SIZE&gt;, parity: Parity) {
                 bar.update(CTRL, |r| r.with_parity(parity));
             }
         ```

   - IRQ:
      - Move 'static bounds from where clauses to trait declarations for
        IRQ handler traits

   - Misc:
      - Enable the generic_arg_infer Rust feature
      - Extend Bounded with shift operations, single-bit bool
        conversion, and const get()

  Misc:
   - Make deferred_probe_timeout default a Kconfig option
   - Drop auxiliary_dev_pm_ops; the PM core falls back to driver PM
     callbacks when no bus type PM ops are set
   - Add conditional guard support for device_lock()
   - Add ksysfs.c to the DRIVER CORE MAINTAINERS entry
   - Fix kernel-doc warnings in base.h
   - Fix stale reference to memory_block_add_nid() in documentation"

* tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (67 commits)
  bus: fsl-mc: use generic driver_override infrastructure
  s390/ap: use generic driver_override infrastructure
  s390/cio: use generic driver_override infrastructure
  vdpa: use generic driver_override infrastructure
  platform/wmi: use generic driver_override infrastructure
  PCI: use generic driver_override infrastructure
  driver core: make software nodes available earlier
  software node: remove software_node_exit()
  kernel: ksysfs: initialize kernel_kobj earlier
  MAINTAINERS: add ksysfs.c to the DRIVER CORE entry
  drivers/base/memory: fix stale reference to memory_block_add_nid()
  device property: Document how to check for the property presence
  soundwire: debugfs: initialize firmware_file to empty string
  debugfs: fix placement of EXPORT_SYMBOL_GPL for debugfs_create_str()
  debugfs: check for NULL pointer in debugfs_create_str()
  driver core: Make deferred_probe_timeout default a Kconfig option
  driver core: simplify __device_set_driver_override() clearing logic
  driver core: auxiliary bus: Drop auxiliary_dev_pm_ops
  device property: Make modifications of fwnode "flags" thread safe
  rust: devres: embed struct devres_node directly
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Fix NULL pointer dereference in debugfs_create_str()
   - Fix misplaced EXPORT_SYMBOL_GPL for debugfs_create_str()
   - Fix soundwire debugfs NULL pointer dereference from uninitialized
     firmware_file

  device property:
   - Make fwnode flags modifications thread safe; widen the field to
     unsigned long and use set_bit() / clear_bit() based accessors
   - Document how to check for the property presence

  devres:
   - Separate struct devres_node from its "subclasses" (struct devres,
     struct devres_group); give struct devres_node its own release and
     free callbacks for per-type dispatch
   - Introduce struct devres_action for devres actions, avoiding the
     ARCH_DMA_MINALIGN alignment overhead of struct devres
   - Export struct devres_node and its init/add/remove/dbginfo
     primitives for use by Rust Devres&lt;T&gt;
   - Fix missing node debug info in devm_krealloc()
   - Use guard(spinlock_irqsave) where applicable; consolidate unlock
     paths in devres_release_group()

  driver_override:
   - Convert PCI, WMI, vdpa, s390/cio, s390/ap, and fsl-mc to the
     generic driver_override infrastructure, replacing per-bus
     driver_override strings, sysfs attributes, and match logic; fixes a
     potential UAF from unsynchronized access to driver_override in bus
     match() callbacks
   - Simplify __device_set_driver_override() logic

  kernfs:
   - Send IN_DELETE_SELF and IN_IGNORED inotify events on kernfs file
     and directory removal
   - Add corresponding selftests for memcg

  platform:
   - Allow attaching software nodes when creating platform devices via a
     new 'swnode' field in struct platform_device_info
   - Add kerneldoc for struct platform_device_info

  software node:
   - Move software node initialization from postcore_initcall() to
     driver_init(), making it available early in the boot process
   - Move kernel_kobj initialization (ksysfs_init) earlier to support
     the above
   - Remove software_node_exit(); dead code in a built-in unit

  SoC:
   - Introduce of_machine_read_compatible() and of_machine_read_model()
     OF helpers and export soc_attr_read_machine() to replace direct
     accesses to of_root from SoC drivers; also enables
     CONFIG_COMPILE_TEST coverage for these drivers

  sysfs:
   - Constify attribute group array pointers to
     'const struct attribute_group *const *' in sysfs functions,
     device_add_groups() / device_remove_groups(), and struct class

  Rust:
   - Devres:
      - Embed struct devres_node directly in Devres&lt;T&gt; instead of going
        through devm_add_action(), avoiding the extra allocation and the
        unnecessary ARCH_DMA_MINALIGN alignment

   - I/O:
      - Turn IoCapable from a marker trait into a functional trait
        carrying the raw I/O accessor implementation (io_read /
        io_write), providing working defaults for the per-type Io
        methods
      - Add RelaxedMmio wrapper type, making relaxed accessors usable in
        code generic over the Io trait
      - Remove overloaded per-type Io methods and per-backend macros
        from Mmio and PCI ConfigSpace

   - I/O (Register):
      - Add IoLoc trait and generic read/write/update methods to the Io
        trait, making I/O operations parameterizable by typed locations
      - Add register! macro for defining hardware register types with
        typed bitfield accessors backed by Bounded values; supports
        direct, relative, and array register addressing
      - Add write_reg() / try_write_reg() and LocatedRegister trait
      - Update PCI sample driver to demonstrate the register! macro

         Example:

         ```
             register! {
                 /// UART control register.
                 CTRL(u32) @ 0x18 {
                     /// Receiver enable.
                     19:19   rx_enable =&gt; bool;
                     /// Parity configuration.
                     14:13   parity ?=&gt; Parity;
                 }

                 /// FIFO watermark and counter register.
                 WATER(u32) @ 0x2c {
                     /// Number of datawords in the receive FIFO.
                     26:24   rx_count;
                     /// RX interrupt threshold.
                     17:16   rx_water;
                 }
             }

             impl WATER {
                 fn rx_above_watermark(&amp;self) -&gt; bool {
                     self.rx_count() &gt; self.rx_water()
                 }
             }

             fn init(bar: &amp;pci::Bar&lt;BAR0_SIZE&gt;) {
                 let water = WATER::zeroed()
                     .with_const_rx_water::&lt;1&gt;(); // &gt; 3 would not compile
                 bar.write_reg(water);

                 let ctrl = CTRL::zeroed()
                     .with_parity(Parity::Even)
                     .with_rx_enable(true);
                 bar.write_reg(ctrl);
             }

             fn handle_rx(bar: &amp;pci::Bar&lt;BAR0_SIZE&gt;) {
                 if bar.read(WATER).rx_above_watermark() {
                     // drain the FIFO
                 }
             }

             fn set_parity(bar: &amp;pci::Bar&lt;BAR0_SIZE&gt;, parity: Parity) {
                 bar.update(CTRL, |r| r.with_parity(parity));
             }
         ```

   - IRQ:
      - Move 'static bounds from where clauses to trait declarations for
        IRQ handler traits

   - Misc:
      - Enable the generic_arg_infer Rust feature
      - Extend Bounded with shift operations, single-bit bool
        conversion, and const get()

  Misc:
   - Make deferred_probe_timeout default a Kconfig option
   - Drop auxiliary_dev_pm_ops; the PM core falls back to driver PM
     callbacks when no bus type PM ops are set
   - Add conditional guard support for device_lock()
   - Add ksysfs.c to the DRIVER CORE MAINTAINERS entry
   - Fix kernel-doc warnings in base.h
   - Fix stale reference to memory_block_add_nid() in documentation"

* tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (67 commits)
  bus: fsl-mc: use generic driver_override infrastructure
  s390/ap: use generic driver_override infrastructure
  s390/cio: use generic driver_override infrastructure
  vdpa: use generic driver_override infrastructure
  platform/wmi: use generic driver_override infrastructure
  PCI: use generic driver_override infrastructure
  driver core: make software nodes available earlier
  software node: remove software_node_exit()
  kernel: ksysfs: initialize kernel_kobj earlier
  MAINTAINERS: add ksysfs.c to the DRIVER CORE entry
  drivers/base/memory: fix stale reference to memory_block_add_nid()
  device property: Document how to check for the property presence
  soundwire: debugfs: initialize firmware_file to empty string
  debugfs: fix placement of EXPORT_SYMBOL_GPL for debugfs_create_str()
  debugfs: check for NULL pointer in debugfs_create_str()
  driver core: Make deferred_probe_timeout default a Kconfig option
  driver core: simplify __device_set_driver_override() clearing logic
  driver core: auxiliary bus: Drop auxiliary_dev_pm_ops
  device property: Make modifications of fwnode "flags" thread safe
  rust: devres: embed struct devres_node directly
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>kernfs: pass struct ns_common instead of const void * for namespace tags</title>
<updated>2026-04-09T12:36:52+00:00</updated>
<author>
<name>Christian Brauner</name>
<email>brauner@kernel.org</email>
</author>
<published>2026-04-01T10:15:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e3b2cf6e5dba416a03152f299d99982dfe1e861d'/>
<id>e3b2cf6e5dba416a03152f299d99982dfe1e861d</id>
<content type='text'>
kernfs has historically used const void * to pass around namespace tags
used for directory-level namespace filtering. The only current user of
this is sysfs network namespace tagging where struct net pointers are
cast to void *.

Replace all const void * namespace parameters with const struct
ns_common * throughout the kernfs, sysfs, and kobject namespace layers.
This includes the kobj_ns_type_operations callbacks, kobject_namespace(),
and all sysfs/kernfs APIs that accept or return namespace tags.

Passing struct ns_common is needed because various codepaths require
access to the underlying namespace. A struct ns_common can always be
converted back to the concrete namespace type (e.g., struct net) via
container_of() or to_ns_common() in the reverse direction.

This is a preparatory change for switching to ns_id-based directory
iteration to prevent a KASLR pointer leak through the current use of
raw namespace pointers as hash seeds and comparison keys.

Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
kernfs has historically used const void * to pass around namespace tags
used for directory-level namespace filtering. The only current user of
this is sysfs network namespace tagging where struct net pointers are
cast to void *.

Replace all const void * namespace parameters with const struct
ns_common * throughout the kernfs, sysfs, and kobject namespace layers.
This includes the kobj_ns_type_operations callbacks, kobject_namespace(),
and all sysfs/kernfs APIs that accept or return namespace tags.

Passing struct ns_common is needed because various codepaths require
access to the underlying namespace. A struct ns_common can always be
converted back to the concrete namespace type (e.g., struct net) via
container_of() or to_ns_common() in the reverse direction.

This is a preparatory change for switching to ns_id-based directory
iteration to prevent a KASLR pointer leak through the current use of
raw namespace pointers as hash seeds and comparison keys.

Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysfs: constify group arrays in function arguments</title>
<updated>2026-03-13T09:21:31+00:00</updated>
<author>
<name>Heiner Kallweit</name>
<email>hkallweit1@gmail.com</email>
</author>
<published>2026-03-01T12:30:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=fe2511adb1fc1814df06ca11e0d8a92f792e4029'/>
<id>fe2511adb1fc1814df06ca11e0d8a92f792e4029</id>
<content type='text'>
Constify the groups array argument where applicable. This allows to
pass constant arrays as arguments.

Signed-off-by: Heiner Kallweit &lt;hkallweit1@gmail.com&gt;
Link: https://patch.msgid.link/17035265-8882-4101-b7a7-16b3eb94f8b5@gmail.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>
Constify the groups array argument where applicable. This allows to
pass constant arrays as arguments.

Signed-off-by: Heiner Kallweit &lt;hkallweit1@gmail.com&gt;
Link: https://patch.msgid.link/17035265-8882-4101-b7a7-16b3eb94f8b5@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kernel.h: move VERIFY_OCTAL_PERMISSIONS() to sysfs.h</title>
<updated>2026-02-01T00:16:05+00:00</updated>
<author>
<name>Yury Norov</name>
<email>ynorov@nvidia.com</email>
</author>
<published>2026-01-16T04:25:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=90ddd39b881df74b14918cee031154f6ddb7af33'/>
<id>90ddd39b881df74b14918cee031154f6ddb7af33</id>
<content type='text'>
The macro is related to sysfs, but is defined in kernel.h.  Move it to the
proper header, and unload the generic kernel.h.

Now that the macro is removed from kernel.h, linux/moduleparam.h is
decoupled, and kernel.h inclusion can be removed.

Link: https://lkml.kernel.org/r/20260116042510.241009-4-ynorov@nvidia.com
Signed-off-by: Yury Norov &lt;ynorov@nvidia.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Tested-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Petr Pavlu &lt;petr.pavlu@suse.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Joel Fernandes &lt;joelagnelf@nvidia.com&gt;
Cc: Aaron Tomlin &lt;atomlin@atomlin.com&gt;
Cc: Andi Shyti &lt;andi.shyti@linux.intel.com&gt;
Cc: Christophe Leroy (CS GROUP) &lt;chleroy@kernel.org&gt;
Cc: Jani Nikula &lt;jani.nikula@intel.com&gt;
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.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>
The macro is related to sysfs, but is defined in kernel.h.  Move it to the
proper header, and unload the generic kernel.h.

Now that the macro is removed from kernel.h, linux/moduleparam.h is
decoupled, and kernel.h inclusion can be removed.

Link: https://lkml.kernel.org/r/20260116042510.241009-4-ynorov@nvidia.com
Signed-off-by: Yury Norov &lt;ynorov@nvidia.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Tested-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Petr Pavlu &lt;petr.pavlu@suse.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Joel Fernandes &lt;joelagnelf@nvidia.com&gt;
Cc: Aaron Tomlin &lt;atomlin@atomlin.com&gt;
Cc: Andi Shyti &lt;andi.shyti@linux.intel.com&gt;
Cc: Christophe Leroy (CS GROUP) &lt;chleroy@kernel.org&gt;
Cc: Jani Nikula &lt;jani.nikula@intel.com&gt;
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysfs: simplify attribute definition macros</title>
<updated>2025-11-26T14:16:35+00:00</updated>
<author>
<name>Thomas Weißschuh</name>
<email>linux@weissschuh.net</email>
</author>
<published>2025-10-29T08:12:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=71464949b1f5f8b8599d057fea525a2a520f84d8'/>
<id>71464949b1f5f8b8599d057fea525a2a520f84d8</id>
<content type='text'>
Define the macros in terms of each other.
This makes them easier to understand and also will make it easier to
implement the transition machinery for 'const struct attribute'.

__ATTR_RO_MODE() can't be implemented in terms of __ATTR() as not all
attributes have a .store callback. The same issue theoretically exists
for __ATTR_WO(), but practically that does not occur today.

Reorder __ATTR_RO() below __ATTR_RO_MODE() to keep the order of the
macro definition consistent with respect to each other.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-7-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Define the macros in terms of each other.
This makes them easier to understand and also will make it easier to
implement the transition machinery for 'const struct attribute'.

__ATTR_RO_MODE() can't be implemented in terms of __ATTR() as not all
attributes have a .store callback. The same issue theoretically exists
for __ATTR_WO(), but practically that does not occur today.

Reorder __ATTR_RO() below __ATTR_RO_MODE() to keep the order of the
macro definition consistent with respect to each other.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-7-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysfs: attribute_group: enable const variants of is_visible()</title>
<updated>2025-11-26T14:16:35+00:00</updated>
<author>
<name>Thomas Weißschuh</name>
<email>linux@weissschuh.net</email>
</author>
<published>2025-10-29T08:12:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7dd9fdb4939b972c1d0523e94fb3f70789653f0c'/>
<id>7dd9fdb4939b972c1d0523e94fb3f70789653f0c</id>
<content type='text'>
When constifying instances of struct attribute, for consistency the
corresponding .is_visible() callback should be adapted, too.
Introduce a temporary transition mechanism until all callbacks are
converted.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-4-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When constifying instances of struct attribute, for consistency the
corresponding .is_visible() callback should be adapted, too.
Introduce a temporary transition mechanism until all callbacks are
converted.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-4-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE()</title>
<updated>2025-11-26T14:16:35+00:00</updated>
<author>
<name>Thomas Weißschuh</name>
<email>linux@weissschuh.net</email>
</author>
<published>2025-10-29T08:12:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=02ac5335a55111d87a7a618355261b4407ed0f7f'/>
<id>02ac5335a55111d87a7a618355261b4407ed0f7f</id>
<content type='text'>
For the constification phase of 'struct attribute' various callback
struct members will need to exist in both const and non-const variants.
Keeping both members in a union avoids memory and CPU overhead but will
be detected and trapped by Control Flow Integrity (CFI). By deciding
between a struct and a union depending whether CFI is enabled, most
configurations can avoid this overhead. Code using these callbacks will
still need to be updated to handle both members explicitly.
In the union case the compiler will recognize that testing for one union
member is enough and optimize away the code for the other one.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-3-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For the constification phase of 'struct attribute' various callback
struct members will need to exist in both const and non-const variants.
Keeping both members in a union avoids memory and CPU overhead but will
be detected and trapped by Control Flow Integrity (CFI). By deciding
between a struct and a union depending whether CFI is enabled, most
configurations can avoid this overhead. Code using these callbacks will
still need to be updated to handle both members explicitly.
In the union case the compiler will recognize that testing for one union
member is enough and optimize away the code for the other one.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-3-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS()</title>
<updated>2025-11-26T14:16:35+00:00</updated>
<author>
<name>Thomas Weißschuh</name>
<email>linux@weissschuh.net</email>
</author>
<published>2025-10-29T08:12:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=964c93b1eef37e3bbe0edb37346c076217d71fe7'/>
<id>964c93b1eef37e3bbe0edb37346c076217d71fe7</id>
<content type='text'>
To ease the constification process of 'struct attribute', transparently
handle the const pointers in ATTRIBUTE_GROUPS(). A cast is used instead
of assigning to .attrs_new as it keeps the macro smaller. As both
members are aliased to each other the result is identical.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-2-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To ease the constification process of 'struct attribute', transparently
handle the const pointers in ATTRIBUTE_GROUPS(). A cast is used instead
of assigning to .attrs_new as it keeps the macro smaller. As both
members are aliased to each other the result is identical.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-2-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysfs: attribute_group: allow registration of const attribute</title>
<updated>2025-11-26T14:16:34+00:00</updated>
<author>
<name>Thomas Weißschuh</name>
<email>linux@weissschuh.net</email>
</author>
<published>2025-10-29T08:12:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f85d90dd8d0efbc75e79698e147c6e682df22e1a'/>
<id>f85d90dd8d0efbc75e79698e147c6e682df22e1a</id>
<content type='text'>
To be able to constify instances of struct attribute it has to be
possible to add them to struct attribute_group. The current type of the
attrs member however is not compatible with that. Introduce a union that
allows registration of both const and non-const attributes to enable a
piecewise transition. As both union member types are compatible no
logic needs to be adapted.

Technically it is now possible register a const struct attribute and
receive it as mutable pointer in the callbacks. This is a soundness
issue.  But this same soundness issue already exists today in
sysfs_create_file(). Also the struct definition and callback
implementation are always closely linked and are meant to be moved to
const in lockstep.

Similar to commit 906c508afdca ("sysfs: attribute_group: allow
registration of const bin_attribute")

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-1-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To be able to constify instances of struct attribute it has to be
possible to add them to struct attribute_group. The current type of the
attrs member however is not compatible with that. Introduce a union that
allows registration of both const and non-const attributes to enable a
piecewise transition. As both union member types are compatible no
logic needs to be adapted.

Technically it is now possible register a const struct attribute and
receive it as mutable pointer in the callbacks. This is a soundness
issue.  But this same soundness issue already exists today in
sysfs_create_file(). Also the struct definition and callback
implementation are always closely linked and are meant to be moved to
const in lockstep.

Similar to commit 906c508afdca ("sysfs: attribute_group: allow
registration of const bin_attribute")

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-1-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysfs: remove attribute_group::bin_attrs_new</title>
<updated>2025-08-19T11:12:12+00:00</updated>
<author>
<name>Thomas Weißschuh</name>
<email>linux@weissschuh.net</email>
</author>
<published>2025-08-11T09:13:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=44d454fcffa8b08d6d66df132121c1d387fa85db'/>
<id>44d454fcffa8b08d6d66df132121c1d387fa85db</id>
<content type='text'>
This transitional field is now unused and unnecessary.
Remove it.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://lore.kernel.org/r/20250811-sysfs-const-bin_attr-final-v4-2-7b6053fd58bb@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This transitional field is now unused and unnecessary.
Remove it.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Link: https://lore.kernel.org/r/20250811-sysfs-const-bin_attr-final-v4-2-7b6053fd58bb@weissschuh.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
