linux-stable.git/drivers/base/dd.c, branch linux-6.3.y Linux kernel stable tree driver core: Don't require dynamic_debug for initcall_debug probe timing 2023-04-30T23:32:26+00:00 Stephen Boyd swboyd@chromium.org 2023-04-12T22:58:42+00:00 c009ead55b57dca89f17d460062dc2a5a9f6e445 commit e2f06aa885081e1391916367f53bad984714b4db upstream. Don't require the use of dynamic debug (or modification of the kernel to add a #define DEBUG to the top of this file) to get the printk message about driver probe timing. This printk is only emitted when initcall_debug is enabled on the kernel commandline, and it isn't immediately obvious that you have to do something else to debug boot timing issues related to driver probe. Add a comment too so it doesn't get converted back to pr_debug(). Fixes: eb7fbc9fb118 ("driver core: Add missing '\n' in log messages") Cc: stable <stable@kernel.org> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Brian Norris <briannorris@chromium.org> Reviewed-by: Brian Norris <briannorris@chromium.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Link: https://lore.kernel.org/r/20230412225842.3196599-1-swboyd@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e2f06aa885081e1391916367f53bad984714b4db upstream.

Don't require the use of dynamic debug (or modification of the kernel to
add a #define DEBUG to the top of this file) to get the printk message
about driver probe timing. This printk is only emitted when
initcall_debug is enabled on the kernel commandline, and it isn't
immediately obvious that you have to do something else to debug boot
timing issues related to driver probe. Add a comment too so it doesn't
get converted back to pr_debug().

Fixes: eb7fbc9fb118 ("driver core: Add missing '\n' in log messages")
Cc: stable <stable@kernel.org>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Brian Norris <briannorris@chromium.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20230412225842.3196599-1-swboyd@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers: base: dd: fix memory leak with using debugfs_lookup() 2023-02-08T12:33:13+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2023-02-02T14:16:21+00:00 36c893d3a759ae7c91ee7d4871ebfc7504f08c40 When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Link: https://lore.kernel.org/r/20230202141621.2296458-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230202141621.2296458-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: bus: move bus notifier logic into bus.c 2023-01-18T08:00:48+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2023-01-11T09:23:31+00:00 ed9f918174cb35ba51d2fc86a613305dd8bc4cfe The logic to touch the bus notifier was open-coded in numberous places in the driver core. Clean that up by creating a local bus_notify() function and have everyone call this function instead, making the reading of the caller code simpler and easier to maintain over time. Reviewed-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20230111092331.3946745-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The logic to touch the bus notifier was open-coded in numberous places
in the driver core.  Clean that up by creating a local bus_notify()
function and have everyone call this function instead, making the
reading of the caller code simpler and easier to maintain over time.

Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230111092331.3946745-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Make driver_deferred_probe_timeout a static variable 2023-01-11T15:06:40+00:00 Javier Martinez Canillas javierm@redhat.com 2022-12-27T23:21:52+00:00 504fa212d7030fb1c042290dc2eb92b21515573a It is not used outside of its compilation unit, so there's no need to export this variable. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Andrew Halaney <ahalaney@redhat.com> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/r/20221227232152.3094584-1-javierm@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
It is not used outside of its compilation unit, so there's no need to
export this variable.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Acked-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/r/20221227232152.3094584-1-javierm@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Fix bus_type.match() error handling in __driver_attach() 2022-11-10T17:36:04+00:00 Isaac J. Manjarres isaacmanjarres@google.com 2022-09-21T00:14:13+00:00 27c0d217340e47ec995557f61423ef415afba987 When a driver registers with a bus, it will attempt to match with every device on the bus through the __driver_attach() function. Currently, if the bus_type.match() function encounters an error that is not -EPROBE_DEFER, __driver_attach() will return a negative error code, which causes the driver registration logic to stop trying to match with the remaining devices on the bus. This behavior is not correct; a failure while matching a driver to a device does not mean that the driver won't be able to match and bind with other devices on the bus. Update the logic in __driver_attach() to reflect this. Fixes: 656b8035b0ee ("ARM: 8524/1: driver cohandle -EPROBE_DEFER from bus_type.match()") Cc: stable@vger.kernel.org Cc: Saravana Kannan <saravanak@google.com> Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com> Link: https://lore.kernel.org/r/20220921001414.4046492-1-isaacmanjarres@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
When a driver registers with a bus, it will attempt to match with every
device on the bus through the __driver_attach() function. Currently, if
the bus_type.match() function encounters an error that is not
-EPROBE_DEFER, __driver_attach() will return a negative error code, which
causes the driver registration logic to stop trying to match with the
remaining devices on the bus.

This behavior is not correct; a failure while matching a driver to a
device does not mean that the driver won't be able to match and bind
with other devices on the bus. Update the logic in __driver_attach()
to reflect this.

Fixes: 656b8035b0ee ("ARM: 8524/1: driver cohandle -EPROBE_DEFER from bus_type.match()")
Cc: stable@vger.kernel.org
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Link: https://lore.kernel.org/r/20220921001414.4046492-1-isaacmanjarres@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: mark driver_allows_async_probing static 2022-11-10T17:31:04+00:00 Christoph Hellwig hch@lst.de 2022-10-30T09:22:55+00:00 189a87f8ef8ceed16b2a230dc0ce65117068ac30 driver_allows_async_probing is only used in drivers/base/dd.c, so mark it static and remove the declaration in drivers/base/base.h. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20221030092255.872280-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
driver_allows_async_probing is only used in drivers/base/dd.c, so mark
it static and remove the declaration in drivers/base/base.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030092255.872280-1-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge 6.0-rc5 into driver-core-next 2022-09-12T14:51:22+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2022-09-12T14:51:22+00:00 a791dc135325862fdf491ac088f54993710e2515 We need the driver core and debugfs changes in this branch. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
We need the driver core and debugfs changes in this branch.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver_core: move from strlcpy with unused retval to strscpy 2022-09-01T16:15:32+00:00 Wolfram Sang wsa+renesas@sang-engineering.com 2022-08-18T20:59:56+00:00 07b7b883be5ba0b4bd9ebf8d72c236ef36ae2676 Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20220818205956.6528-1-wsa+renesas@sang-engineering.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220818205956.6528-1-wsa+renesas@sang-engineering.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Don't probe devices after bus_type.match() probe deferral 2022-09-01T13:57:13+00:00 Isaac J. Manjarres isaacmanjarres@google.com 2022-08-17T18:40:26+00:00 25e9fbf0fd38868a429feabc38abebfc6dbf6542 Both __device_attach_driver() and __driver_attach() check the return code of the bus_type.match() function to see if the device needs to be added to the deferred probe list. After adding the device to the list, the logic attempts to bind the device to the driver anyway, as if the device had matched with the driver, which is not correct. If __device_attach_driver() detects that the device in question is not ready to match with a driver on the bus, then it doesn't make sense for the device to attempt to bind with the current driver or continue attempting to match with any of the other drivers on the bus. So, update the logic in __device_attach_driver() to reflect this. If __driver_attach() detects that a driver tried to match with a device that is not ready to match yet, then the driver should not attempt to bind with the device. However, the driver can still attempt to match and bind with other devices on the bus, as drivers can be bound to multiple devices. So, update the logic in __driver_attach() to reflect this. Fixes: 656b8035b0ee ("ARM: 8524/1: driver cohandle -EPROBE_DEFER from bus_type.match()") Cc: stable@vger.kernel.org Cc: Saravana Kannan <saravanak@google.com> Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com> Link: https://lore.kernel.org/r/20220817184026.3468620-1-isaacmanjarres@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Both __device_attach_driver() and __driver_attach() check the return
code of the bus_type.match() function to see if the device needs to be
added to the deferred probe list. After adding the device to the list,
the logic attempts to bind the device to the driver anyway, as if the
device had matched with the driver, which is not correct.

If __device_attach_driver() detects that the device in question is not
ready to match with a driver on the bus, then it doesn't make sense for
the device to attempt to bind with the current driver or continue
attempting to match with any of the other drivers on the bus. So, update
the logic in __device_attach_driver() to reflect this.

If __driver_attach() detects that a driver tried to match with a device
that is not ready to match yet, then the driver should not attempt to bind
with the device. However, the driver can still attempt to match and bind
with other devices on the bus, as drivers can be bound to multiple
devices. So, update the logic in __driver_attach() to reflect this.

Fixes: 656b8035b0ee ("ARM: 8524/1: driver cohandle -EPROBE_DEFER from bus_type.match()")
Cc: stable@vger.kernel.org
Cc: Saravana Kannan <saravanak@google.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Link: https://lore.kernel.org/r/20220817184026.3468620-1-isaacmanjarres@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "driver core: Delete driver_deferred_probe_check_state()" 2022-08-23T11:14:02+00:00 Saravana Kannan saravanak@google.com 2022-08-19T22:16:11+00:00 13a8e0f6b01b14b2e28ba144e112c883f03a3db2 This reverts commit 9cbffc7a59561be950ecc675d19a3d2b45202b2b. There are a few more issues to fix that have been reported in the thread for the original series [1]. We'll need to fix those before this will work. So, revert it for now. [1] - https://lore.kernel.org/lkml/20220601070707.3946847-1-saravanak@google.com/ Fixes: 9cbffc7a5956 ("driver core: Delete driver_deferred_probe_check_state()") Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Peng Fan <peng.fan@nxp.com> Tested-by: Douglas Anderson <dianders@chromium.org> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20220819221616.2107893-2-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
This reverts commit 9cbffc7a59561be950ecc675d19a3d2b45202b2b.

There are a few more issues to fix that have been reported in the thread
for the original series [1]. We'll need to fix those before this will work.
So, revert it for now.

[1] - https://lore.kernel.org/lkml/20220601070707.3946847-1-saravanak@google.com/

Fixes: 9cbffc7a5956 ("driver core: Delete driver_deferred_probe_check_state()")
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Peng Fan <peng.fan@nxp.com>
Tested-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20220819221616.2107893-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>