<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/base, branch v5.15-rc5</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge tag 'driver-core-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core</title>
<updated>2021-10-03T18:10:09+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-10-03T18:10:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=84928ce3bb4e20ec7ef0e990630a690855dd44cc'/>
<id>84928ce3bb4e20ec7ef0e990630a690855dd44cc</id>
<content type='text'>
Pull driver core fixes from Greg KH:
 "Here are some driver core and kernfs fixes for reported issues for
  5.15-rc4. These fixes include:

   - kernfs positive dentry bugfix

   - debugfs_create_file_size error path fix

   - cpumask sysfs file bugfix to preserve the user/kernel abi (has been
     reported multiple times.)

   - devlink fixes for mdiobus devices as reported by the subsystem
     maintainers.

  Also included in here are some devlink debugging changes to make it
  easier for people to report problems when asked. They have already
  helped with the mdiobus and other subsystems reporting issues.

  All of these have been linux-next for a while with no reported issues"

* tag 'driver-core-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kernfs: also call kernfs_set_rev() for positive dentry
  driver core: Add debug logs when fwnode links are added/deleted
  driver core: Create __fwnode_link_del() helper function
  driver core: Set deferred probe reason when deferred by driver core
  net: mdiobus: Set FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD for mdiobus parents
  driver core: fw_devlink: Add support for FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD
  driver core: fw_devlink: Improve handling of cyclic dependencies
  cpumask: Omit terminating null byte in cpumap_print_{list,bitmask}_to_buf
  debugfs: debugfs_create_file_size(): use IS_ERR to check for error
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull driver core fixes from Greg KH:
 "Here are some driver core and kernfs fixes for reported issues for
  5.15-rc4. These fixes include:

   - kernfs positive dentry bugfix

   - debugfs_create_file_size error path fix

   - cpumask sysfs file bugfix to preserve the user/kernel abi (has been
     reported multiple times.)

   - devlink fixes for mdiobus devices as reported by the subsystem
     maintainers.

  Also included in here are some devlink debugging changes to make it
  easier for people to report problems when asked. They have already
  helped with the mdiobus and other subsystems reporting issues.

  All of these have been linux-next for a while with no reported issues"

* tag 'driver-core-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kernfs: also call kernfs_set_rev() for positive dentry
  driver core: Add debug logs when fwnode links are added/deleted
  driver core: Create __fwnode_link_del() helper function
  driver core: Set deferred probe reason when deferred by driver core
  net: mdiobus: Set FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD for mdiobus parents
  driver core: fw_devlink: Add support for FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD
  driver core: fw_devlink: Improve handling of cyclic dependencies
  cpumask: Omit terminating null byte in cpumap_print_{list,bitmask}_to_buf
  debugfs: debugfs_create_file_size(): use IS_ERR to check for error
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: Add debug logs when fwnode links are added/deleted</title>
<updated>2021-09-28T07:48:48+00:00</updated>
<author>
<name>Saravana Kannan</name>
<email>saravanak@google.com</email>
</author>
<published>2021-09-15T17:28:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ebd6823af378c7d91f80cbe83ce07b5f166744e4'/>
<id>ebd6823af378c7d91f80cbe83ce07b5f166744e4</id>
<content type='text'>
This will help with debugging fw_devlink issues.

Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915172808.620546-4-saravanak@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>
This will help with debugging fw_devlink issues.

Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915172808.620546-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: Create __fwnode_link_del() helper function</title>
<updated>2021-09-28T07:48:48+00:00</updated>
<author>
<name>Saravana Kannan</name>
<email>saravanak@google.com</email>
</author>
<published>2021-09-15T17:28:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=76f130810b477243ce1312bf5754dc41ce7f91a8'/>
<id>76f130810b477243ce1312bf5754dc41ce7f91a8</id>
<content type='text'>
The same code is repeated in multiple locations. Create a helper
function for it.

Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915172808.620546-3-saravanak@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 same code is repeated in multiple locations. Create a helper
function for it.

Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915172808.620546-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: Set deferred probe reason when deferred by driver core</title>
<updated>2021-09-28T07:48:48+00:00</updated>
<author>
<name>Saravana Kannan</name>
<email>saravanak@google.com</email>
</author>
<published>2021-09-15T17:28:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=68223eeec70898cd5e42451a9168cd9b2808e248'/>
<id>68223eeec70898cd5e42451a9168cd9b2808e248</id>
<content type='text'>
When the driver core defers the probe of a device, set the deferred
probe reason so that it's easier to debug. The deferred probe reason is
available in debugfs under devices_deferred.

Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915172808.620546-2-saravanak@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>
When the driver core defers the probe of a device, set the deferred
probe reason so that it's easier to debug. The deferred probe reason is
available in debugfs under devices_deferred.

Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915172808.620546-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'devprop-5.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2021-09-24T18:20:29+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-09-24T18:20:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=47d7e65d64cc72756b1aa0ccfa3dcbd38c638507'/>
<id>47d7e65d64cc72756b1aa0ccfa3dcbd38c638507</id>
<content type='text'>
Pull device properties framework fix from Rafael Wysocki:
 "Fix software node refcount imbalance on device removal (Laurentiu
  Tudor)"

* tag 'devprop-5.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  software node: balance refcount for managed software nodes
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull device properties framework fix from Rafael Wysocki:
 "Fix software node refcount imbalance on device removal (Laurentiu
  Tudor)"

* tag 'devprop-5.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  software node: balance refcount for managed software nodes
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: fw_devlink: Add support for FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD</title>
<updated>2021-09-23T17:26:54+00:00</updated>
<author>
<name>Saravana Kannan</name>
<email>saravanak@google.com</email>
</author>
<published>2021-09-15T17:09:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5501765a02a6c324f78581e6bb8209d054fe13ae'/>
<id>5501765a02a6c324f78581e6bb8209d054fe13ae</id>
<content type='text'>
If a parent device is also a supplier to a child device, fw_devlink=on by
design delays the probe() of the child device until the probe() of the
parent finishes successfully.

However, some drivers of such parent devices (where parent is also a
supplier) expect the child device to finish probing successfully as soon as
they are added using device_add() and before the probe() of the parent
device has completed successfully. One example of such a case is discussed
in the link mentioned below.

Add a flag to make fw_devlink=on not enforce these supplier-consumer
relationships, so these drivers can continue working.

Link: https://lore.kernel.org/netdev/CAGETcx_uj0V4DChME-gy5HGKTYnxLBX=TH2rag29f_p=UcG+Tg@mail.gmail.com/
Fixes: ea718c699055 ("Revert "Revert "driver core: Set fw_devlink=on by default""")
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915170940.617415-3-saravanak@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>
If a parent device is also a supplier to a child device, fw_devlink=on by
design delays the probe() of the child device until the probe() of the
parent finishes successfully.

However, some drivers of such parent devices (where parent is also a
supplier) expect the child device to finish probing successfully as soon as
they are added using device_add() and before the probe() of the parent
device has completed successfully. One example of such a case is discussed
in the link mentioned below.

Add a flag to make fw_devlink=on not enforce these supplier-consumer
relationships, so these drivers can continue working.

Link: https://lore.kernel.org/netdev/CAGETcx_uj0V4DChME-gy5HGKTYnxLBX=TH2rag29f_p=UcG+Tg@mail.gmail.com/
Fixes: ea718c699055 ("Revert "Revert "driver core: Set fw_devlink=on by default""")
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915170940.617415-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: fw_devlink: Improve handling of cyclic dependencies</title>
<updated>2021-09-21T16:21:48+00:00</updated>
<author>
<name>Saravana Kannan</name>
<email>saravanak@google.com</email>
</author>
<published>2021-09-15T17:09:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2de9d8e0d2fe3a1eb632def2245529067cb35db5'/>
<id>2de9d8e0d2fe3a1eb632def2245529067cb35db5</id>
<content type='text'>
When we have a dependency of the form:

Device-A -&gt; Device-C
	Device-B

Device-C -&gt; Device-B

Where,
* Indentation denotes "child of" parent in previous line.
* X -&gt; Y denotes X is consumer of Y based on firmware (Eg: DT).

We have cyclic dependency: device-A -&gt; device-C -&gt; device-B -&gt; device-A

fw_devlink current treats device-C -&gt; device-B dependency as an invalid
dependency and doesn't enforce it but leaves the rest of the
dependencies as is.

While the current behavior is necessary, it is not sufficient if the
false dependency in this example is actually device-A -&gt; device-C. When
this is the case, device-C will correctly probe defer waiting for
device-B to be added, but device-A will be incorrectly probe deferred by
fw_devlink waiting on device-C to probe successfully. Due to this, none
of the devices in the cycle will end up probing.

To fix this, we need to go relax all the dependencies in the cycle like
we already do in the other instances where fw_devlink detects cycles.
A real world example of this was reported[1] and analyzed[2].

[1] - https://lore.kernel.org/lkml/0a2c4106-7f48-2bb5-048e-8c001a7c3fda@samsung.com/
[2] - https://lore.kernel.org/lkml/CAGETcx8peaew90SWiux=TyvuGgvTQOmO4BFALz7aj0Za5QdNFQ@mail.gmail.com/

Fixes: f9aa460672c9 ("driver core: Refactor fw_devlink feature")
Cc: stable &lt;stable@vger.kernel.org&gt;
Reported-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Tested-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915170940.617415-2-saravanak@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>
When we have a dependency of the form:

Device-A -&gt; Device-C
	Device-B

Device-C -&gt; Device-B

Where,
* Indentation denotes "child of" parent in previous line.
* X -&gt; Y denotes X is consumer of Y based on firmware (Eg: DT).

We have cyclic dependency: device-A -&gt; device-C -&gt; device-B -&gt; device-A

fw_devlink current treats device-C -&gt; device-B dependency as an invalid
dependency and doesn't enforce it but leaves the rest of the
dependencies as is.

While the current behavior is necessary, it is not sufficient if the
false dependency in this example is actually device-A -&gt; device-C. When
this is the case, device-C will correctly probe defer waiting for
device-B to be added, but device-A will be incorrectly probe deferred by
fw_devlink waiting on device-C to probe successfully. Due to this, none
of the devices in the cycle will end up probing.

To fix this, we need to go relax all the dependencies in the cycle like
we already do in the other instances where fw_devlink detects cycles.
A real world example of this was reported[1] and analyzed[2].

[1] - https://lore.kernel.org/lkml/0a2c4106-7f48-2bb5-048e-8c001a7c3fda@samsung.com/
[2] - https://lore.kernel.org/lkml/CAGETcx8peaew90SWiux=TyvuGgvTQOmO4BFALz7aj0Za5QdNFQ@mail.gmail.com/

Fixes: f9aa460672c9 ("driver core: Refactor fw_devlink feature")
Cc: stable &lt;stable@vger.kernel.org&gt;
Reported-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Tested-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Saravana Kannan &lt;saravanak@google.com&gt;
Link: https://lore.kernel.org/r/20210915170940.617415-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus-5.15b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip</title>
<updated>2021-09-17T15:31:49+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-09-17T15:31:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c6460daea23dcd160f2dc497c64b4c882ea1de69'/>
<id>c6460daea23dcd160f2dc497c64b4c882ea1de69</id>
<content type='text'>
Pull xen fixes from Juergen Gross:

 - The first hunk of a Xen swiotlb fixup series fixing multiple minor
   issues and doing some small cleanups

 - Some further Xen related fixes avoiding WARN() splats when running as
   Xen guests or dom0

 - A Kconfig fix allowing the pvcalls frontend to be built as a module

* tag 'for-linus-5.15b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  swiotlb-xen: drop DEFAULT_NSLABS
  swiotlb-xen: arrange to have buffer info logged
  swiotlb-xen: drop leftover __ref
  swiotlb-xen: limit init retries
  swiotlb-xen: suppress certain init retries
  swiotlb-xen: maintain slab count properly
  swiotlb-xen: fix late init retry
  swiotlb-xen: avoid double free
  xen/pvcalls: backend can be a module
  xen: fix usage of pmd_populate in mremap for pv guests
  xen: reset legacy rtc flag for PV domU
  PM: base: power: don't try to use non-existing RTC for storing data
  xen/balloon: use a kernel thread instead a workqueue
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull xen fixes from Juergen Gross:

 - The first hunk of a Xen swiotlb fixup series fixing multiple minor
   issues and doing some small cleanups

 - Some further Xen related fixes avoiding WARN() splats when running as
   Xen guests or dom0

 - A Kconfig fix allowing the pvcalls frontend to be built as a module

* tag 'for-linus-5.15b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  swiotlb-xen: drop DEFAULT_NSLABS
  swiotlb-xen: arrange to have buffer info logged
  swiotlb-xen: drop leftover __ref
  swiotlb-xen: limit init retries
  swiotlb-xen: suppress certain init retries
  swiotlb-xen: maintain slab count properly
  swiotlb-xen: fix late init retry
  swiotlb-xen: avoid double free
  xen/pvcalls: backend can be a module
  xen: fix usage of pmd_populate in mremap for pv guests
  xen: reset legacy rtc flag for PV domU
  PM: base: power: don't try to use non-existing RTC for storing data
  xen/balloon: use a kernel thread instead a workqueue
</pre>
</div>
</content>
</entry>
<entry>
<title>software node: balance refcount for managed software nodes</title>
<updated>2021-09-16T11:13:48+00:00</updated>
<author>
<name>Laurentiu Tudor</name>
<email>laurentiu.tudor@nxp.com</email>
</author>
<published>2021-09-15T08:09:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5aeb05b27f81269a2bf2e15eab9fc0f9a400d3a8'/>
<id>5aeb05b27f81269a2bf2e15eab9fc0f9a400d3a8</id>
<content type='text'>
software_node_notify(), on KOBJ_REMOVE drops the refcount twice on managed
software nodes, thus leading to underflow errors. Balance the refcount by
bumping it in the device_create_managed_software_node() function.

The error [1] was encountered after adding a .shutdown() op to our
fsl-mc-bus driver.

[1]
pc : refcount_warn_saturate+0xf8/0x150
lr : refcount_warn_saturate+0xf8/0x150
sp : ffff80001009b920
x29: ffff80001009b920 x28: ffff1a2420318000 x27: 0000000000000000
x26: ffffccac15e7a038 x25: 0000000000000008 x24: ffffccac168e0030
x23: ffff1a2428a82000 x22: 0000000000080000 x21: ffff1a24287b5000
x20: 0000000000000001 x19: ffff1a24261f4400 x18: ffffffffffffffff
x17: 6f72645f726f7272 x16: 0000000000000000 x15: ffff80009009b607
x14: 0000000000000000 x13: ffffccac16602670 x12: 0000000000000a17
x11: 000000000000035d x10: ffffccac16602670 x9 : ffffccac16602670
x8 : 00000000ffffefff x7 : ffffccac1665a670 x6 : ffffccac1665a670
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 00000000ffffffff
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff1a2420318000
Call trace:
 refcount_warn_saturate+0xf8/0x150
 kobject_put+0x10c/0x120
 software_node_notify+0xd8/0x140
 device_platform_notify+0x4c/0xb4
 device_del+0x188/0x424
 fsl_mc_device_remove+0x2c/0x4c
 rebofind sp.c__fsl_mc_device_remove+0x14/0x2c
 device_for_each_child+0x5c/0xac
 dprc_remove+0x9c/0xc0
 fsl_mc_driver_remove+0x28/0x64
 __device_release_driver+0x188/0x22c
 device_release_driver+0x30/0x50
 bus_remove_device+0x128/0x134
 device_del+0x16c/0x424
 fsl_mc_bus_remove+0x8c/0x114
 fsl_mc_bus_shutdown+0x14/0x20
 platform_shutdown+0x28/0x40
 device_shutdown+0x15c/0x330
 __do_sys_reboot+0x218/0x2a0
 __arm64_sys_reboot+0x28/0x34
 invoke_syscall+0x48/0x114
 el0_svc_common+0x40/0xdc
 do_el0_svc+0x2c/0x94
 el0_svc+0x2c/0x54
 el0t_64_sync_handler+0xa8/0x12c
 el0t_64_sync+0x198/0x19c
---[ end trace 32eb1c71c7d86821 ]---

Fixes: 151f6ff78cdf ("software node: Provide replacement for device_add_properties()")
Reported-by: Jon Nettleton &lt;jon@solid-run.com&gt;
Suggested-by: Heikki Krogerus &lt;heikki.krogerus@linux.intel.com&gt;
Reviewed-by: Heikki Krogerus &lt;heikki.krogerus@linux.intel.com&gt;
Signed-off-by: Laurentiu Tudor &lt;laurentiu.tudor@nxp.com&gt;
Cc: 5.12+ &lt;stable@vger.kernel.org&gt; # 5.12+
[ rjw: Fix up the software_node_notify() invocation ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
software_node_notify(), on KOBJ_REMOVE drops the refcount twice on managed
software nodes, thus leading to underflow errors. Balance the refcount by
bumping it in the device_create_managed_software_node() function.

The error [1] was encountered after adding a .shutdown() op to our
fsl-mc-bus driver.

[1]
pc : refcount_warn_saturate+0xf8/0x150
lr : refcount_warn_saturate+0xf8/0x150
sp : ffff80001009b920
x29: ffff80001009b920 x28: ffff1a2420318000 x27: 0000000000000000
x26: ffffccac15e7a038 x25: 0000000000000008 x24: ffffccac168e0030
x23: ffff1a2428a82000 x22: 0000000000080000 x21: ffff1a24287b5000
x20: 0000000000000001 x19: ffff1a24261f4400 x18: ffffffffffffffff
x17: 6f72645f726f7272 x16: 0000000000000000 x15: ffff80009009b607
x14: 0000000000000000 x13: ffffccac16602670 x12: 0000000000000a17
x11: 000000000000035d x10: ffffccac16602670 x9 : ffffccac16602670
x8 : 00000000ffffefff x7 : ffffccac1665a670 x6 : ffffccac1665a670
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 00000000ffffffff
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff1a2420318000
Call trace:
 refcount_warn_saturate+0xf8/0x150
 kobject_put+0x10c/0x120
 software_node_notify+0xd8/0x140
 device_platform_notify+0x4c/0xb4
 device_del+0x188/0x424
 fsl_mc_device_remove+0x2c/0x4c
 rebofind sp.c__fsl_mc_device_remove+0x14/0x2c
 device_for_each_child+0x5c/0xac
 dprc_remove+0x9c/0xc0
 fsl_mc_driver_remove+0x28/0x64
 __device_release_driver+0x188/0x22c
 device_release_driver+0x30/0x50
 bus_remove_device+0x128/0x134
 device_del+0x16c/0x424
 fsl_mc_bus_remove+0x8c/0x114
 fsl_mc_bus_shutdown+0x14/0x20
 platform_shutdown+0x28/0x40
 device_shutdown+0x15c/0x330
 __do_sys_reboot+0x218/0x2a0
 __arm64_sys_reboot+0x28/0x34
 invoke_syscall+0x48/0x114
 el0_svc_common+0x40/0xdc
 do_el0_svc+0x2c/0x94
 el0_svc+0x2c/0x54
 el0t_64_sync_handler+0xa8/0x12c
 el0t_64_sync+0x198/0x19c
---[ end trace 32eb1c71c7d86821 ]---

Fixes: 151f6ff78cdf ("software node: Provide replacement for device_add_properties()")
Reported-by: Jon Nettleton &lt;jon@solid-run.com&gt;
Suggested-by: Heikki Krogerus &lt;heikki.krogerus@linux.intel.com&gt;
Reviewed-by: Heikki Krogerus &lt;heikki.krogerus@linux.intel.com&gt;
Signed-off-by: Laurentiu Tudor &lt;laurentiu.tudor@nxp.com&gt;
Cc: 5.12+ &lt;stable@vger.kernel.org&gt; # 5.12+
[ rjw: Fix up the software_node_notify() invocation ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>memblock: introduce saner 'memblock_free_ptr()' interface</title>
<updated>2021-09-14T20:23:22+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-09-14T20:23:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=77e02cf57b6cff9919949defb7fd9b8ac16399a2'/>
<id>77e02cf57b6cff9919949defb7fd9b8ac16399a2</id>
<content type='text'>
The boot-time allocation interface for memblock is a mess, with
'memblock_alloc()' returning a virtual pointer, but then you are
supposed to free it with 'memblock_free()' that takes a _physical_
address.

Not only is that all kinds of strange and illogical, but it actually
causes bugs, when people then use it like a normal allocation function,
and it fails spectacularly on a NULL pointer:

   https://lore.kernel.org/all/20210912140820.GD25450@xsang-OptiPlex-9020/

or just random memory corruption if the debug checks don't catch it:

   https://lore.kernel.org/all/61ab2d0c-3313-aaab-514c-e15b7aa054a0@suse.cz/

I really don't want to apply patches that treat the symptoms, when the
fundamental cause is this horribly confusing interface.

I started out looking at just automating a sane replacement sequence,
but because of this mix or virtual and physical addresses, and because
people have used the "__pa()" macro that can take either a regular
kernel pointer, or just the raw "unsigned long" address, it's all quite
messy.

So this just introduces a new saner interface for freeing a virtual
address that was allocated using 'memblock_alloc()', and that was kept
as a regular kernel pointer.  And then it converts a couple of users
that are obvious and easy to test, including the 'xbc_nodes' case in
lib/bootconfig.c that caused problems.

Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Fixes: 40caa127f3c7 ("init: bootconfig: Remove all bootconfig data when the init memory is removed")
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The boot-time allocation interface for memblock is a mess, with
'memblock_alloc()' returning a virtual pointer, but then you are
supposed to free it with 'memblock_free()' that takes a _physical_
address.

Not only is that all kinds of strange and illogical, but it actually
causes bugs, when people then use it like a normal allocation function,
and it fails spectacularly on a NULL pointer:

   https://lore.kernel.org/all/20210912140820.GD25450@xsang-OptiPlex-9020/

or just random memory corruption if the debug checks don't catch it:

   https://lore.kernel.org/all/61ab2d0c-3313-aaab-514c-e15b7aa054a0@suse.cz/

I really don't want to apply patches that treat the symptoms, when the
fundamental cause is this horribly confusing interface.

I started out looking at just automating a sane replacement sequence,
but because of this mix or virtual and physical addresses, and because
people have used the "__pa()" macro that can take either a regular
kernel pointer, or just the raw "unsigned long" address, it's all quite
messy.

So this just introduces a new saner interface for freeing a virtual
address that was allocated using 'memblock_alloc()', and that was kept
as a regular kernel pointer.  And then it converts a couple of users
that are obvious and easy to test, including the 'xbc_nodes' case in
lib/bootconfig.c that caused problems.

Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Fixes: 40caa127f3c7 ("init: bootconfig: Remove all bootconfig data when the init memory is removed")
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
