<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/usb/host, branch linux-4.9.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>xhci: Remove device endpoints from bandwidth list when freeing the device</title>
<updated>2022-11-03T14:49:16+00:00</updated>
<author>
<name>Mathias Nyman</name>
<email>mathias.nyman@linux.intel.com</email>
</author>
<published>2022-10-24T14:27:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5e4ce28ad907aa54f13b21d5f1dc490525957b0c'/>
<id>5e4ce28ad907aa54f13b21d5f1dc490525957b0c</id>
<content type='text'>
commit 5aed5b7c2430ce318a8e62f752f181e66f0d1053 upstream.

Endpoints are normally deleted from the bandwidth list when they are
dropped, before the virt device is freed.

If xHC host is dying or being removed then the endpoints aren't dropped
cleanly due to functions returning early to avoid interacting with a
non-accessible host controller.

So check and delete endpoints that are still on the bandwidth list when
freeing the virt device.

Solves a list_del corruption kernel crash when unbinding xhci-pci,
caused by xhci_mem_cleanup() when it later tried to delete already freed
endpoints from the bandwidth list.

This only affects hosts that use software bandwidth checking, which
currenty is only the xHC in intel Panther Point PCH (Ivy Bridge)

Cc: stable@vger.kernel.org
Reported-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Tested-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20221024142720.4122053-5-mathias.nyman@intel.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>
commit 5aed5b7c2430ce318a8e62f752f181e66f0d1053 upstream.

Endpoints are normally deleted from the bandwidth list when they are
dropped, before the virt device is freed.

If xHC host is dying or being removed then the endpoints aren't dropped
cleanly due to functions returning early to avoid interacting with a
non-accessible host controller.

So check and delete endpoints that are still on the bandwidth list when
freeing the virt device.

Solves a list_del corruption kernel crash when unbinding xhci-pci,
caused by xhci_mem_cleanup() when it later tried to delete already freed
endpoints from the bandwidth list.

This only affects hosts that use software bandwidth checking, which
currenty is only the xHC in intel Panther Point PCH (Ivy Bridge)

Cc: stable@vger.kernel.org
Reported-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Tested-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20221024142720.4122053-5-mathias.nyman@intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: host: xhci: Fix potential memory leak in xhci_alloc_stream_info()</title>
<updated>2022-10-26T11:15:47+00:00</updated>
<author>
<name>Jianglei Nie</name>
<email>niejianglei2021@163.com</email>
</author>
<published>2022-09-21T12:34:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7fc6bab3413e6a42bb1264ff7c9149808c93a4c7'/>
<id>7fc6bab3413e6a42bb1264ff7c9149808c93a4c7</id>
<content type='text'>
[ Upstream commit 7e271f42a5cc3768cd2622b929ba66859ae21f97 ]

xhci_alloc_stream_info() allocates stream context array for stream_info
-&gt;stream_ctx_array with xhci_alloc_stream_ctx(). When some error occurs,
stream_info-&gt;stream_ctx_array is not released, which will lead to a
memory leak.

We can fix it by releasing the stream_info-&gt;stream_ctx_array with
xhci_free_stream_ctx() on the error path to avoid the potential memory
leak.

Signed-off-by: Jianglei Nie &lt;niejianglei2021@163.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220921123450.671459-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7e271f42a5cc3768cd2622b929ba66859ae21f97 ]

xhci_alloc_stream_info() allocates stream context array for stream_info
-&gt;stream_ctx_array with xhci_alloc_stream_ctx(). When some error occurs,
stream_info-&gt;stream_ctx_array is not released, which will lead to a
memory leak.

We can fix it by releasing the stream_info-&gt;stream_ctx_array with
xhci_free_stream_ctx() on the error path to avoid the potential memory
leak.

Signed-off-by: Jianglei Nie &lt;niejianglei2021@163.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220921123450.671459-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xhci: Add grace period after xHC start to prevent premature runtime suspend.</title>
<updated>2022-09-15T10:39:45+00:00</updated>
<author>
<name>Mathias Nyman</name>
<email>mathias.nyman@linux.intel.com</email>
</author>
<published>2022-08-25T15:08:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e7a5c01912cc4a8865692cfb418aa1362f8e51e5'/>
<id>e7a5c01912cc4a8865692cfb418aa1362f8e51e5</id>
<content type='text'>
commit 33e321586e37b642ad10594b9ef25a613555cd08 upstream.

After xHC controller is started, either in probe or resume, it can take
a while before any of the connected usb devices are visible to the roothub
due to link training.

It's possible xhci driver loads, sees no acivity and suspends the host
before the USB device is visible.

In one testcase with a hotplugged xHC controller the host finally detected
the connected USB device and generated a wake 500ms after host initial
start.

If hosts didn't suspend the device duringe training it probablty wouldn't
take up to 500ms to detect it, but looking at specs reveal USB3 link
training has a couple long timeout values, such as 120ms
RxDetectQuietTimeout, and 360ms PollingLFPSTimeout.

So Add a 500ms grace period that keeps polling the roothub for 500ms after
start, preventing runtime suspend until USB devices are detected.

Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220825150840.132216-3-mathias.nyman@linux.intel.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>
commit 33e321586e37b642ad10594b9ef25a613555cd08 upstream.

After xHC controller is started, either in probe or resume, it can take
a while before any of the connected usb devices are visible to the roothub
due to link training.

It's possible xhci driver loads, sees no acivity and suspends the host
before the USB device is visible.

In one testcase with a hotplugged xHC controller the host finally detected
the connected USB device and generated a wake 500ms after host initial
start.

If hosts didn't suspend the device duringe training it probablty wouldn't
take up to 500ms to detect it, but looking at specs reveal USB3 link
training has a couple long timeout values, such as 120ms
RxDetectQuietTimeout, and 360ms PollingLFPSTimeout.

So Add a 500ms grace period that keeps polling the roothub for 500ms after
start, preventing runtime suspend until USB devices are detected.

Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220825150840.132216-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: host: ohci-ppc-of: Fix refcount leak bug</title>
<updated>2022-08-25T09:09:30+00:00</updated>
<author>
<name>Liang He</name>
<email>windhl@126.com</email>
</author>
<published>2022-06-17T03:46:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fe6fe64403710287f0ae61a516954d8a4f7c9e3f'/>
<id>fe6fe64403710287f0ae61a516954d8a4f7c9e3f</id>
<content type='text'>
[ Upstream commit 40a959d7042bb7711e404ad2318b30e9f92c6b9b ]

In ohci_hcd_ppc_of_probe(), of_find_compatible_node() will return
a node pointer with refcount incremented. We should use of_node_put()
when it is not used anymore.

Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Signed-off-by: Liang He &lt;windhl@126.com&gt;
Link: https://lore.kernel.org/r/20220617034637.4003115-1-windhl@126.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 40a959d7042bb7711e404ad2318b30e9f92c6b9b ]

In ohci_hcd_ppc_of_probe(), of_find_compatible_node() will return
a node pointer with refcount incremented. We should use of_node_put()
when it is not used anymore.

Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Signed-off-by: Liang He &lt;windhl@126.com&gt;
Link: https://lore.kernel.org/r/20220617034637.4003115-1-windhl@126.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drivers: usb: host: Fix deadlock in oxu_bus_suspend()</title>
<updated>2022-06-14T14:52:40+00:00</updated>
<author>
<name>Duoming Zhou</name>
<email>duoming@zju.edu.cn</email>
</author>
<published>2022-04-17T12:03:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9b58d255f27b0ed6a2e43208960864d67579db58'/>
<id>9b58d255f27b0ed6a2e43208960864d67579db58</id>
<content type='text'>
[ Upstream commit 4d378f2ae58138d4c55684e1d274e7dd94aa6524 ]

There is a deadlock in oxu_bus_suspend(), which is shown below:

   (Thread 1)              |      (Thread 2)
                           | timer_action()
oxu_bus_suspend()          |  mod_timer()
 spin_lock_irq() //(1)     |  (wait a time)
 ...                       | oxu_watchdog()
 del_timer_sync()          |  spin_lock_irq() //(2)
 (wait timer to stop)      |  ...

We hold oxu-&gt;lock in position (1) of thread 1, and use
del_timer_sync() to wait timer to stop, but timer handler
also need oxu-&gt;lock in position (2) of thread 2. As a result,
oxu_bus_suspend() will block forever.

This patch extracts del_timer_sync() from the protection of
spin_lock_irq(), which could let timer handler to obtain
the needed lock.

Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Link: https://lore.kernel.org/r/20220417120305.64577-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4d378f2ae58138d4c55684e1d274e7dd94aa6524 ]

There is a deadlock in oxu_bus_suspend(), which is shown below:

   (Thread 1)              |      (Thread 2)
                           | timer_action()
oxu_bus_suspend()          |  mod_timer()
 spin_lock_irq() //(1)     |  (wait a time)
 ...                       | oxu_watchdog()
 del_timer_sync()          |  spin_lock_irq() //(2)
 (wait timer to stop)      |  ...

We hold oxu-&gt;lock in position (1) of thread 1, and use
del_timer_sync() to wait timer to stop, but timer handler
also need oxu-&gt;lock in position (2) of thread 2. As a result,
oxu_bus_suspend() will block forever.

This patch extracts del_timer_sync() from the protection of
spin_lock_irq(), which could let timer handler to obtain
the needed lock.

Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Link: https://lore.kernel.org/r/20220417120305.64577-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: host: isp116x: check return value after calling platform_get_resource()</title>
<updated>2022-06-14T14:52:39+00:00</updated>
<author>
<name>Zhen Ni</name>
<email>nizhen@uniontech.com</email>
</author>
<published>2022-03-02T03:37:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=804de302ada3544699c5f48c5314b249af76faa3'/>
<id>804de302ada3544699c5f48c5314b249af76faa3</id>
<content type='text'>
[ Upstream commit 134a3408c2d3f7e23eb0e4556e0a2d9f36c2614e ]

It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.

Signed-off-by: Zhen Ni &lt;nizhen@uniontech.com&gt;
Link: https://lore.kernel.org/r/20220302033716.31272-1-nizhen@uniontech.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 134a3408c2d3f7e23eb0e4556e0a2d9f36c2614e ]

It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.

Signed-off-by: Zhen Ni &lt;nizhen@uniontech.com&gt;
Link: https://lore.kernel.org/r/20220302033716.31272-1-nizhen@uniontech.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xhci: stop polling roothubs after shutdown</title>
<updated>2022-05-12T10:14:53+00:00</updated>
<author>
<name>Henry Lin</name>
<email>henryl@nvidia.com</email>
</author>
<published>2022-04-08T13:48:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=60eb65df83e165fdda319998fa7ce7853fa8646d'/>
<id>60eb65df83e165fdda319998fa7ce7853fa8646d</id>
<content type='text'>
commit dc92944a014cd6a6f6c94299aaa36164dd2c238a upstream.

While rebooting, XHCI controller and its bus device will be shut down
in order by .shutdown callback. Stopping roothubs polling in
xhci_shutdown() can prevent XHCI driver from accessing port status
after its bus device shutdown.

Take PCIe XHCI controller as example, if XHCI driver doesn't stop roothubs
polling, XHCI driver may access PCIe BAR register for port status after
parent PCIe root port driver is shutdown and cause PCIe bus error.

[check shared hcd exist before stopping its roothub polling -Mathias]

Cc: stable@vger.kernel.org
Signed-off-by: Henry Lin &lt;henryl@nvidia.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220408134823.2527272-3-mathias.nyman@linux.intel.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>
commit dc92944a014cd6a6f6c94299aaa36164dd2c238a upstream.

While rebooting, XHCI controller and its bus device will be shut down
in order by .shutdown callback. Stopping roothubs polling in
xhci_shutdown() can prevent XHCI driver from accessing port status
after its bus device shutdown.

Take PCIe XHCI controller as example, if XHCI driver doesn't stop roothubs
polling, XHCI driver may access PCIe BAR register for port status after
parent PCIe root port driver is shutdown and cause PCIe bus error.

[check shared hcd exist before stopping its roothub polling -Mathias]

Cc: stable@vger.kernel.org
Signed-off-by: Henry Lin &lt;henryl@nvidia.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220408134823.2527272-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xhci: Prevent futile URB re-submissions due to incorrect return value.</title>
<updated>2022-03-02T10:32:06+00:00</updated>
<author>
<name>Hongyu Xie</name>
<email>xiehongyu1@kylinos.cn</email>
</author>
<published>2022-02-15T12:33:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a750d0ee17404ee03b338894ebe763cbfa021397'/>
<id>a750d0ee17404ee03b338894ebe763cbfa021397</id>
<content type='text'>
commit 243a1dd7ba48c120986dd9e66fee74bcb7751034 upstream.

The -ENODEV return value from xhci_check_args() is incorrectly changed
to -EINVAL in a couple places before propagated further.

xhci_check_args() returns 4 types of value, -ENODEV, -EINVAL, 1 and 0.
xhci_urb_enqueue and xhci_check_streams_endpoint return -EINVAL if
the return value of xhci_check_args &lt;= 0.
This causes problems for example r8152_submit_rx, calling usb_submit_urb
in drivers/net/usb/r8152.c.
r8152_submit_rx will never get -ENODEV after submiting an urb when xHC
is halted because xhci_urb_enqueue returns -EINVAL in the very beginning.

[commit message and header edit -Mathias]

Fixes: 203a86613fb3 ("xhci: Avoid NULL pointer deref when host dies.")
Cc: stable@vger.kernel.org
Signed-off-by: Hongyu Xie &lt;xiehongyu1@kylinos.cn&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220215123320.1253947-3-mathias.nyman@linux.intel.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>
commit 243a1dd7ba48c120986dd9e66fee74bcb7751034 upstream.

The -ENODEV return value from xhci_check_args() is incorrectly changed
to -EINVAL in a couple places before propagated further.

xhci_check_args() returns 4 types of value, -ENODEV, -EINVAL, 1 and 0.
xhci_urb_enqueue and xhci_check_streams_endpoint return -EINVAL if
the return value of xhci_check_args &lt;= 0.
This causes problems for example r8152_submit_rx, calling usb_submit_urb
in drivers/net/usb/r8152.c.
r8152_submit_rx will never get -ENODEV after submiting an urb when xHC
is halted because xhci_urb_enqueue returns -EINVAL in the very beginning.

[commit message and header edit -Mathias]

Fixes: 203a86613fb3 ("xhci: Avoid NULL pointer deref when host dies.")
Cc: stable@vger.kernel.org
Signed-off-by: Hongyu Xie &lt;xiehongyu1@kylinos.cn&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220215123320.1253947-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xhci: Fresco FL1100 controller should not have BROKEN_MSI quirk set.</title>
<updated>2022-01-05T11:31:25+00:00</updated>
<author>
<name>Mathias Nyman</name>
<email>mathias.nyman@linux.intel.com</email>
</author>
<published>2021-12-21T11:28:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d575894d1bcd046c4232f2f37eb85d9bc9bf6ea9'/>
<id>d575894d1bcd046c4232f2f37eb85d9bc9bf6ea9</id>
<content type='text'>
commit e4844092581ceec22489b66c42edc88bc6079783 upstream.

The Fresco Logic FL1100 controller needs the TRUST_TX_LENGTH quirk like
other Fresco controllers, but should not have the BROKEN_MSI quirks set.

BROKEN_MSI quirk causes issues in detecting usb drives connected to docks
with this FL1100 controller.
The BROKEN_MSI flag was apparently accidentally set together with the
TRUST_TX_LENGTH quirk

Original patch went to stable so this should go there as well.

Fixes: ea0f69d82119 ("xhci: Enable trust tx length quirk for Fresco FL11 USB controller")
Cc: stable@vger.kernel.org
cc: Nikolay Martynov &lt;mar.kolya@gmail.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20211221112825.54690-2-mathias.nyman@linux.intel.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>
commit e4844092581ceec22489b66c42edc88bc6079783 upstream.

The Fresco Logic FL1100 controller needs the TRUST_TX_LENGTH quirk like
other Fresco controllers, but should not have the BROKEN_MSI quirks set.

BROKEN_MSI quirk causes issues in detecting usb drives connected to docks
with this FL1100 controller.
The BROKEN_MSI flag was apparently accidentally set together with the
TRUST_TX_LENGTH quirk

Original patch went to stable so this should go there as well.

Fixes: ea0f69d82119 ("xhci: Enable trust tx length quirk for Fresco FL11 USB controller")
Cc: stable@vger.kernel.org
cc: Nikolay Martynov &lt;mar.kolya@gmail.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20211221112825.54690-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: max-3421: Use driver data instead of maintaining a list of bound devices</title>
<updated>2021-11-26T10:48:43+00:00</updated>
<author>
<name>Uwe Kleine-König</name>
<email>u.kleine-koenig@pengutronix.de</email>
</author>
<published>2021-10-18T20:40:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=146934b127652b0aef8972bc1318a24251fc17a5'/>
<id>146934b127652b0aef8972bc1318a24251fc17a5</id>
<content type='text'>
commit fc153aba3ef371d0d76eb88230ed4e0dee5b38f2 upstream.

Instead of maintaining a single-linked list of devices that must be
searched linearly in .remove() just use spi_set_drvdata() to remember the
link between the spi device and the driver struct. Then the global list
and the next member can be dropped.

This simplifies the driver, reduces the memory footprint and the time to
search the list. Also it makes obvious that there is always a corresponding
driver struct for a given device in .remove(), so the error path for
!max3421_hcd can be dropped, too.

As a side effect this fixes a data inconsistency when .probe() races with
itself for a second max3421 device in manipulating max3421_hcd_list. A
similar race is fixed in .remove(), too.

Fixes: 2d53139f3162 ("Add support for using a MAX3421E chip as a host driver.")
Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20211018204028.2914597-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit fc153aba3ef371d0d76eb88230ed4e0dee5b38f2 upstream.

Instead of maintaining a single-linked list of devices that must be
searched linearly in .remove() just use spi_set_drvdata() to remember the
link between the spi device and the driver struct. Then the global list
and the next member can be dropped.

This simplifies the driver, reduces the memory footprint and the time to
search the list. Also it makes obvious that there is always a corresponding
driver struct for a given device in .remove(), so the error path for
!max3421_hcd can be dropped, too.

As a side effect this fixes a data inconsistency when .probe() races with
itself for a second max3421 device in manipulating max3421_hcd_list. A
similar race is fixed in .remove(), too.

Fixes: 2d53139f3162 ("Add support for using a MAX3421E chip as a host driver.")
Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20211018204028.2914597-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
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