linux-stable.git/drivers/base, branch v5.10.95 Linux kernel stable tree device property: Fix fwnode_graph_devcon_match() fwnode leak 2022-01-27T09:54:25+00:00 Sakari Ailus sakari.ailus@linux.intel.com 2021-12-01T12:59:29+00:00 6c1e3d8b1bff4c861c9ebe2d37a5b296fc7ee207 commit 4a7f4110f79163fd53ea65438041994ed615e3af upstream. For each endpoint it encounters, fwnode_graph_devcon_match() checks whether the endpoint's remote port parent device is available. If it is not, it ignores the endpoint but does not put the reference to the remote endpoint port parent fwnode. For available devices the fwnode handle reference is put as expected. Put the reference for unavailable devices now. Fixes: 637e9e52b185 ("device connection: Find device connections also from device graphs") Cc: 5.1+ <stable@vger.kernel.org> # 5.1+ Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 4a7f4110f79163fd53ea65438041994ed615e3af upstream.

For each endpoint it encounters, fwnode_graph_devcon_match() checks
whether the endpoint's remote port parent device is available. If it is
not, it ignores the endpoint but does not put the reference to the remote
endpoint port parent fwnode. For available devices the fwnode handle
reference is put as expected.

Put the reference for unavailable devices now.

Fixes: 637e9e52b185 ("device connection: Find device connections also from device graphs")
Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PM: runtime: Add safety net to supplier device release 2022-01-27T09:54:17+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2021-12-10T16:10:13+00:00 37b25de3af10a3082f9ef5888de0f8602c5dcadf [ Upstream commit d1579e61192e0e686faa4208500ef4c3b529b16c ] Because refcount_dec_not_one() returns true if the target refcount becomes saturated, it is generally unsafe to use its return value as a loop termination condition, but that is what happens when a device link's supplier device is released during runtime PM suspend operations and on device link removal. To address this, introduce pm_runtime_release_supplier() to be used in the above cases which will check the supplier device's runtime PM usage counter in addition to the refcount_dec_not_one() return value, so the loop can be terminated in case the rpm_active refcount value becomes invalid, and update the code in question to use it as appropriate. This change is not expected to have any visible functional impact. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d1579e61192e0e686faa4208500ef4c3b529b16c ]

Because refcount_dec_not_one() returns true if the target refcount
becomes saturated, it is generally unsafe to use its return value as
a loop termination condition, but that is what happens when a device
link's supplier device is released during runtime PM suspend
operations and on device link removal.

To address this, introduce pm_runtime_release_supplier() to be used
in the above cases which will check the supplier device's runtime
PM usage counter in addition to the refcount_dec_not_one() return
value, so the loop can be terminated in case the rpm_active refcount
value becomes invalid, and update the code in question to use it as
appropriate.

This change is not expected to have any visible functional impact.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
regmap: Call regmap_debugfs_exit() prior to _init() 2022-01-27T09:54:03+00:00 Fabio Estevam festevam@denx.de 2022-01-07T16:33:07+00:00 d71fca5d0167f250a351f2fe9f9f0659aaa41a69 [ Upstream commit 530792efa6cb86f5612ff093333fec735793b582 ] Since commit cffa4b2122f5 ("regmap: debugfs: Fix a memory leak when calling regmap_attach_dev"), the following debugfs error is seen on i.MX boards: debugfs: Directory 'dummy-iomuxc-gpr@20e0000' with parent 'regmap' already present! In the attempt to fix the memory leak, the above commit added a NULL check for map->debugfs_name. For the first debufs entry, map->debugfs_name is NULL and then the new name is allocated via kasprintf(). For the second debugfs entry, map->debugfs_name() is no longer NULL, so it will keep using the old entry name and the duplicate name error is seen. Quoting Mark Brown: "That means that if the device gets freed we'll end up with the old debugfs file hanging around pointing at nothing. ... To be more explicit this means we need a call to regmap_debugfs_exit() which will clean up all the existing debugfs stuff before we loose references to it." Call regmap_debugfs_exit() prior to regmap_debugfs_init() to fix the problem. Tested on i.MX6Q and i.MX6SX boards. Fixes: cffa4b2122f5 ("regmap: debugfs: Fix a memory leak when calling regmap_attach_dev") Suggested-by: Mark Brown <broonie@kernel.org> Signed-off-by: Fabio Estevam <festevam@denx.de> Link: https://lore.kernel.org/r/20220107163307.335404-1-festevam@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 530792efa6cb86f5612ff093333fec735793b582 ]

Since commit cffa4b2122f5 ("regmap: debugfs: Fix a memory leak when
calling regmap_attach_dev"), the following debugfs error is seen
on i.MX boards:

debugfs: Directory 'dummy-iomuxc-gpr@20e0000' with parent 'regmap' already present!

In the attempt to fix the memory leak, the above commit added a NULL check
for map->debugfs_name. For the first debufs entry, map->debugfs_name is NULL
and then the new name is allocated via kasprintf().

For the second debugfs entry, map->debugfs_name() is no longer NULL, so
it will keep using the old entry name and the duplicate name error is seen.

Quoting Mark Brown:

"That means that if the device gets freed we'll end up with the old debugfs
file hanging around pointing at nothing.
...
To be more explicit this means we need a call to regmap_debugfs_exit()
which will clean up all the existing debugfs stuff before we loose
references to it."

Call regmap_debugfs_exit() prior to regmap_debugfs_init() to fix
the problem.

Tested on i.MX6Q and i.MX6SX boards.

Fixes: cffa4b2122f5 ("regmap: debugfs: Fix a memory leak when calling regmap_attach_dev")
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://lore.kernel.org/r/20220107163307.335404-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
software node: fix wrong node passed to find nargs_prop 2022-01-27T09:53:59+00:00 Clément Léger clement.leger@bootlin.com 2021-12-20T21:05:33+00:00 1d4e722b62d2b6ca1ba0a83687230b47c41a16da [ Upstream commit c5fc5ba8b6b7bebc05e45036a33405b4c5036c2f ] nargs_prop refers to a property located in the reference that is found within the nargs property. Use the correct reference node in call to property_entry_read_int_array() to retrieve the correct nargs value. Fixes: b06184acf751 ("software node: Add software_node_get_reference_args()") Signed-off-by: Clément Léger <clement.leger@bootlin.com> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Daniel Scally <djrscally@gmail.com> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit c5fc5ba8b6b7bebc05e45036a33405b4c5036c2f ]

nargs_prop refers to a property located in the reference that is found
within the nargs property. Use the correct reference node in call to
property_entry_read_int_array() to retrieve the correct nargs value.

Fixes: b06184acf751 ("software node: Add software_node_get_reference_args()")
Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Daniel Scally <djrscally@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
devtmpfs regression fix: reconfigure on each mount 2022-01-20T08:17:49+00:00 NeilBrown neilb@suse.de 2022-01-16T22:07:26+00:00 0084fefe2960b3a0c6482558272ee6372c75e3d4 commit a6097180d884ddab769fb25588ea8598589c218c upstream. Prior to Linux v5.4 devtmpfs used mount_single() which treats the given mount options as "remount" options, so it updates the configuration of the single super_block on each mount. Since that was changed, the mount options used for devtmpfs are ignored. This is a regression which affect systemd - which mounts devtmpfs with "-o mode=755,size=4m,nr_inodes=1m". This patch restores the "remount" effect by calling reconfigure_single() Fixes: d401727ea0d7 ("devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()") Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a6097180d884ddab769fb25588ea8598589c218c upstream.

Prior to Linux v5.4 devtmpfs used mount_single() which treats the given
mount options as "remount" options, so it updates the configuration of
the single super_block on each mount.

Since that was changed, the mount options used for devtmpfs are ignored.
This is a regression which affect systemd - which mounts devtmpfs with
"-o mode=755,size=4m,nr_inodes=1m".

This patch restores the "remount" effect by calling reconfigure_single()

Fixes: d401727ea0d7 ("devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()")
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
firmware_loader: fix pre-allocated buf built-in firmware use 2021-11-26T09:39:10+00:00 Luis Chamberlain mcgrof@kernel.org 2021-09-17T18:22:13+00:00 c6c9bbe7facb10b03aa3b61ee0f8231a414e209a [ Upstream commit f7a07f7b96033df7709042ff38e998720a3f7119 ] The firmware_loader can be used with a pre-allocated buffer through the use of the API calls: o request_firmware_into_buf() o request_partial_firmware_into_buf() If the firmware was built-in and present, our current check for if the built-in firmware fits into the pre-allocated buffer does not return any errors, and we proceed to tell the caller that everything worked fine. It's a lie and no firmware would end up being copied into the pre-allocated buffer. So if the caller trust the result it may end up writing a bunch of 0's to a device! Fix this by making the function that checks for the pre-allocated buffer return non-void. Since the typical use case is when no pre-allocated buffer is provided make this return successfully for that case. If the built-in firmware does *not* fit into the pre-allocated buffer size return a failure as we should have been doing before. I'm not aware of users of the built-in firmware using the API calls with a pre-allocated buffer, as such I doubt this fixes any real life issue. But you never know... perhaps some oddball private tree might use it. In so far as upstream is concerned this just fixes our code for correctness. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20210917182226.3532898-2-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f7a07f7b96033df7709042ff38e998720a3f7119 ]

The firmware_loader can be used with a pre-allocated buffer
through the use of the API calls:

  o request_firmware_into_buf()
  o request_partial_firmware_into_buf()

If the firmware was built-in and present, our current check
for if the built-in firmware fits into the pre-allocated buffer
does not return any errors, and we proceed to tell the caller
that everything worked fine. It's a lie and no firmware would
end up being copied into the pre-allocated buffer. So if the
caller trust the result it may end up writing a bunch of 0's
to a device!

Fix this by making the function that checks for the pre-allocated
buffer return non-void. Since the typical use case is when no
pre-allocated buffer is provided make this return successfully
for that case. If the built-in firmware does *not* fit into the
pre-allocated buffer size return a failure as we should have
been doing before.

I'm not aware of users of the built-in firmware using the API
calls with a pre-allocated buffer, as such I doubt this fixes
any real life issue. But you never know... perhaps some oddball
private tree might use it.

In so far as upstream is concerned this just fixes our code for
correctness.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20210917182226.3532898-2-mcgrof@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
driver core: Fix possible memory leak in device_link_add() 2021-11-18T13:04:16+00:00 Yang Yingliang yangyingliang@huawei.com 2021-09-30T08:57:14+00:00 e1959450b77a2a9226a818993ea55700872c134b [ Upstream commit df0a18149474c7e6b21f6367fbc6bc8d0f192444 ] I got memory leak as follows: unreferenced object 0xffff88801f0b2200 (size 64): comm "i2c-lis2hh12-21", pid 5455, jiffies 4294944606 (age 15.224s) hex dump (first 32 bytes): 72 65 67 75 6c 61 74 6f 72 3a 72 65 67 75 6c 61 regulator:regula 74 6f 72 2e 30 2d 2d 69 32 63 3a 31 2d 30 30 31 tor.0--i2c:1-001 backtrace: [<00000000bf5b0c3b>] __kmalloc_track_caller+0x19f/0x3a0 [<0000000050da42d9>] kvasprintf+0xb5/0x150 [<000000004bbbed13>] kvasprintf_const+0x60/0x190 [<00000000cdac7480>] kobject_set_name_vargs+0x56/0x150 [<00000000bf83f8e8>] dev_set_name+0xc0/0x100 [<00000000cc1cf7e3>] device_link_add+0x6b4/0x17c0 [<000000009db9faed>] _regulator_get+0x297/0x680 [<00000000845e7f2b>] _devm_regulator_get+0x5b/0xe0 [<000000003958ee25>] st_sensors_power_enable+0x71/0x1b0 [st_sensors] [<000000005f450f52>] st_accel_i2c_probe+0xd9/0x150 [st_accel_i2c] [<00000000b5f2ab33>] i2c_device_probe+0x4d8/0xbe0 [<0000000070fb977b>] really_probe+0x299/0xc30 [<0000000088e226ce>] __driver_probe_device+0x357/0x500 [<00000000c21dda32>] driver_probe_device+0x4e/0x140 [<000000004e650441>] __device_attach_driver+0x257/0x340 [<00000000cf1891b8>] bus_for_each_drv+0x166/0x1e0 When device_register() returns an error, the name allocated in dev_set_name() will be leaked, the put_device() should be used instead of kfree() to give up the device reference, then the name will be freed in kobject_cleanup() and the references of consumer and supplier will be decreased in device_link_release_fn(). Fixes: 287905e68dd2 ("driver core: Expose device link details in sysfs") Reported-by: Hulk Robot <hulkci@huawei.com> Reviewed-by: Saravana Kannan <saravanak@google.com> Reviewed-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20210930085714.2057460-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit df0a18149474c7e6b21f6367fbc6bc8d0f192444 ]

I got memory leak as follows:

unreferenced object 0xffff88801f0b2200 (size 64):
  comm "i2c-lis2hh12-21", pid 5455, jiffies 4294944606 (age 15.224s)
  hex dump (first 32 bytes):
    72 65 67 75 6c 61 74 6f 72 3a 72 65 67 75 6c 61  regulator:regula
    74 6f 72 2e 30 2d 2d 69 32 63 3a 31 2d 30 30 31  tor.0--i2c:1-001
  backtrace:
    [<00000000bf5b0c3b>] __kmalloc_track_caller+0x19f/0x3a0
    [<0000000050da42d9>] kvasprintf+0xb5/0x150
    [<000000004bbbed13>] kvasprintf_const+0x60/0x190
    [<00000000cdac7480>] kobject_set_name_vargs+0x56/0x150
    [<00000000bf83f8e8>] dev_set_name+0xc0/0x100
    [<00000000cc1cf7e3>] device_link_add+0x6b4/0x17c0
    [<000000009db9faed>] _regulator_get+0x297/0x680
    [<00000000845e7f2b>] _devm_regulator_get+0x5b/0xe0
    [<000000003958ee25>] st_sensors_power_enable+0x71/0x1b0 [st_sensors]
    [<000000005f450f52>] st_accel_i2c_probe+0xd9/0x150 [st_accel_i2c]
    [<00000000b5f2ab33>] i2c_device_probe+0x4d8/0xbe0
    [<0000000070fb977b>] really_probe+0x299/0xc30
    [<0000000088e226ce>] __driver_probe_device+0x357/0x500
    [<00000000c21dda32>] driver_probe_device+0x4e/0x140
    [<000000004e650441>] __device_attach_driver+0x257/0x340
    [<00000000cf1891b8>] bus_for_each_drv+0x166/0x1e0

When device_register() returns an error, the name allocated in dev_set_name()
will be leaked, the put_device() should be used instead of kfree() to give up
the device reference, then the name will be freed in kobject_cleanup() and the
references of consumer and supplier will be decreased in device_link_release_fn().

Fixes: 287905e68dd2 ("driver core: Expose device link details in sysfs")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210930085714.2057460-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PM: sleep: Do not let "syscore" devices runtime-suspend during system transitions 2021-11-18T13:03:46+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2021-10-22T12:58:23+00:00 daccf40320d41fe7241caa8c47584b934b0fe97f commit 928265e3601cde78c7e0a3e518a93b27defed3b1 upstream. There is no reason to allow "syscore" devices to runtime-suspend during system-wide PM transitions, because they are subject to the same possible failure modes as any other devices in that respect. Accordingly, change device_prepare() and device_complete() to call pm_runtime_get_noresume() and pm_runtime_put(), respectively, for "syscore" devices too. Fixes: 057d51a1268f ("Merge branch 'pm-sleep'") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: 3.10+ <stable@vger.kernel.org> # 3.10+ Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 928265e3601cde78c7e0a3e518a93b27defed3b1 upstream.

There is no reason to allow "syscore" devices to runtime-suspend
during system-wide PM transitions, because they are subject to the
same possible failure modes as any other devices in that respect.

Accordingly, change device_prepare() and device_complete() to call
pm_runtime_get_noresume() and pm_runtime_put(), respectively, for
"syscore" devices too.

Fixes: 057d51a1268f ("Merge branch 'pm-sleep'")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
regmap: Fix possible double-free in regcache_rbtree_exit() 2021-11-02T18:48:22+00:00 Yang Yingliang yangyingliang@huawei.com 2021-10-12T02:37:35+00:00 36e911a16b377bde0ad91a8c679069d0d310b1a6 commit 55e6d8037805b3400096d621091dfbf713f97e83 upstream. In regcache_rbtree_insert_to_block(), when 'present' realloc failed, the 'blk' which is supposed to assign to 'rbnode->block' will be freed, so 'rbnode->block' points a freed memory, in the error handling path of regcache_rbtree_init(), 'rbnode->block' will be freed again in regcache_rbtree_exit(), KASAN will report double-free as follows: BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390 Call Trace: slab_free_freelist_hook+0x10d/0x240 kfree+0xce/0x390 regcache_rbtree_exit+0x15d/0x1a0 regcache_rbtree_init+0x224/0x2c0 regcache_init+0x88d/0x1310 __regmap_init+0x3151/0x4a80 __devm_regmap_init+0x7d/0x100 madera_spi_probe+0x10f/0x333 [madera_spi] spi_probe+0x183/0x210 really_probe+0x285/0xc30 To fix this, moving up the assignment of rbnode->block to immediately after the reallocation has succeeded so that the data structure stays valid even if the second reallocation fails. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 3f4ff561bc88b ("regmap: rbtree: Make cache_present bitmap per node") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20211012023735.1632786-1-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 55e6d8037805b3400096d621091dfbf713f97e83 upstream.

In regcache_rbtree_insert_to_block(), when 'present' realloc failed,
the 'blk' which is supposed to assign to 'rbnode->block' will be freed,
so 'rbnode->block' points a freed memory, in the error handling path of
regcache_rbtree_init(), 'rbnode->block' will be freed again in
regcache_rbtree_exit(), KASAN will report double-free as follows:

BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390
Call Trace:
 slab_free_freelist_hook+0x10d/0x240
 kfree+0xce/0x390
 regcache_rbtree_exit+0x15d/0x1a0
 regcache_rbtree_init+0x224/0x2c0
 regcache_init+0x88d/0x1310
 __regmap_init+0x3151/0x4a80
 __devm_regmap_init+0x7d/0x100
 madera_spi_probe+0x10f/0x333 [madera_spi]
 spi_probe+0x183/0x210
 really_probe+0x285/0xc30

To fix this, moving up the assignment of rbnode->block to immediately after
the reallocation has succeeded so that the data structure stays valid even
if the second reallocation fails.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 3f4ff561bc88b ("regmap: rbtree: Make cache_present bitmap per node")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20211012023735.1632786-1-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Reject pointless SYNC_STATE_ONLY device links 2021-10-20T09:45:01+00:00 Saravana Kannan saravanak@google.com 2021-09-29T19:05:49+00:00 be8ef91d61663bfcc79f5c0eb33f9a26ab74de73 commit f729a592adb6760013c3e48622a5bf256b992452 upstream. SYNC_STATE_ONLY device links intentionally allow cycles because cyclic sync_state() dependencies are valid and necessary. However a SYNC_STATE_ONLY device link where the consumer and the supplier are the same device is pointless because the device link would be deleted as soon as the device probes (because it's also the consumer) and won't affect when the sync_state() callback is called. It's a waste of CPU cycles and memory to create this device link. So reject any attempts to create such a device link. Fixes: 05ef983e0d65 ("driver core: Add device link support for SYNC_STATE_ONLY flag") Cc: stable <stable@vger.kernel.org> Reported-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210929190549.860541-1-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f729a592adb6760013c3e48622a5bf256b992452 upstream.

SYNC_STATE_ONLY device links intentionally allow cycles because cyclic
sync_state() dependencies are valid and necessary.

However a SYNC_STATE_ONLY device link where the consumer and the supplier
are the same device is pointless because the device link would be deleted
as soon as the device probes (because it's also the consumer) and won't
affect when the sync_state() callback is called. It's a waste of CPU cycles
and memory to create this device link. So reject any attempts to create
such a device link.

Fixes: 05ef983e0d65 ("driver core: Add device link support for SYNC_STATE_ONLY flag")
Cc: stable <stable@vger.kernel.org>
Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210929190549.860541-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>