<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/tty/serial, branch v5.4.262</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>tty: serial: meson: fix hard LOCKUP on crtscts mode</title>
<updated>2023-11-28T16:50:20+00:00</updated>
<author>
<name>Pavel Krasavin</name>
<email>pkrasavin@imaqliq.com</email>
</author>
<published>2023-10-14T11:39:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0fe69c99cc133eea7d8b1369b83838272ca62080'/>
<id>0fe69c99cc133eea7d8b1369b83838272ca62080</id>
<content type='text'>
[ Upstream commit 2a1d728f20edeee7f26dc307ed9df4e0d23947ab ]

There might be hard lockup if we set crtscts mode on port without RTS/CTS configured:

# stty -F /dev/ttyAML6 crtscts; echo 1 &gt; /dev/ttyAML6; echo 2 &gt; /dev/ttyAML6
[   95.890386] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
[   95.890857] rcu:     3-...0: (201 ticks this GP) idle=e33c/1/0x4000000000000000 softirq=5844/5846 fqs=4984
[   95.900212] rcu:     (detected by 2, t=21016 jiffies, g=7753, q=296 ncpus=4)
[   95.906972] Task dump for CPU 3:
[   95.910178] task:bash            state:R  running task     stack:0     pid:205   ppid:1      flags:0x00000202
[   95.920059] Call trace:
[   95.922485]  __switch_to+0xe4/0x168
[   95.925951]  0xffffff8003477508
[   95.974379] watchdog: Watchdog detected hard LOCKUP on cpu 3
[   95.974424] Modules linked in: 88x2cs(O) rtc_meson_vrtc

Possible solution would be to not allow to setup crtscts on such port.

Tested on S905X3 based board.

Fixes: ff7693d079e5 ("ARM: meson: serial: add MesonX SoC on-chip uart driver")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Krasavin &lt;pkrasavin@imaqliq.com&gt;
Reviewed-by: Neil Armstrong &lt;neil.armstrong@linaro.org&gt;
Reviewed-by: Dmitry Rokosov &lt;ddrokosov@salutedevices.com&gt;

v6: stable tag added
v5: https://lore.kernel.org/lkml/OF43DA36FF.2BD3BB21-ON00258A47.005A8125-00258A47.005A9513@gdc.ru/
added missed Reviewed-by tags, Fixes tag added according to Dmitry and Neil notes
v4: https://lore.kernel.org/lkml/OF55521400.7512350F-ON00258A47.003F7254-00258A47.0040E15C@gdc.ru/
More correct patch subject according to Jiri's note
v3: https://lore.kernel.org/lkml/OF6CF5FFA0.CCFD0E8E-ON00258A46.00549EDF-00258A46.0054BB62@gdc.ru/
"From:" line added to the mail
v2: https://lore.kernel.org/lkml/OF950BEF72.7F425944-ON00258A46.00488A76-00258A46.00497D44@gdc.ru/
braces for single statement removed according to Dmitry's note
v1: https://lore.kernel.org/lkml/OF28B2B8C9.5BC0CD28-ON00258A46.0037688F-00258A46.0039155B@gdc.ru/
Link: https://lore.kernel.org/r/OF66360032.51C36182-ON00258A48.003F656B-00258A48.0040092C@gdc.ru

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 2a1d728f20edeee7f26dc307ed9df4e0d23947ab ]

There might be hard lockup if we set crtscts mode on port without RTS/CTS configured:

# stty -F /dev/ttyAML6 crtscts; echo 1 &gt; /dev/ttyAML6; echo 2 &gt; /dev/ttyAML6
[   95.890386] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
[   95.890857] rcu:     3-...0: (201 ticks this GP) idle=e33c/1/0x4000000000000000 softirq=5844/5846 fqs=4984
[   95.900212] rcu:     (detected by 2, t=21016 jiffies, g=7753, q=296 ncpus=4)
[   95.906972] Task dump for CPU 3:
[   95.910178] task:bash            state:R  running task     stack:0     pid:205   ppid:1      flags:0x00000202
[   95.920059] Call trace:
[   95.922485]  __switch_to+0xe4/0x168
[   95.925951]  0xffffff8003477508
[   95.974379] watchdog: Watchdog detected hard LOCKUP on cpu 3
[   95.974424] Modules linked in: 88x2cs(O) rtc_meson_vrtc

Possible solution would be to not allow to setup crtscts on such port.

Tested on S905X3 based board.

Fixes: ff7693d079e5 ("ARM: meson: serial: add MesonX SoC on-chip uart driver")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Krasavin &lt;pkrasavin@imaqliq.com&gt;
Reviewed-by: Neil Armstrong &lt;neil.armstrong@linaro.org&gt;
Reviewed-by: Dmitry Rokosov &lt;ddrokosov@salutedevices.com&gt;

v6: stable tag added
v5: https://lore.kernel.org/lkml/OF43DA36FF.2BD3BB21-ON00258A47.005A8125-00258A47.005A9513@gdc.ru/
added missed Reviewed-by tags, Fixes tag added according to Dmitry and Neil notes
v4: https://lore.kernel.org/lkml/OF55521400.7512350F-ON00258A47.003F7254-00258A47.0040E15C@gdc.ru/
More correct patch subject according to Jiri's note
v3: https://lore.kernel.org/lkml/OF6CF5FFA0.CCFD0E8E-ON00258A46.00549EDF-00258A46.0054BB62@gdc.ru/
"From:" line added to the mail
v2: https://lore.kernel.org/lkml/OF950BEF72.7F425944-ON00258A46.00488A76-00258A46.00497D44@gdc.ru/
braces for single statement removed according to Dmitry's note
v1: https://lore.kernel.org/lkml/OF28B2B8C9.5BC0CD28-ON00258A46.0037688F-00258A46.0039155B@gdc.ru/
Link: https://lore.kernel.org/r/OF66360032.51C36182-ON00258A48.003F656B-00258A48.0040092C@gdc.ru

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>serial: meson: Use platform_get_irq() to get the interrupt</title>
<updated>2023-11-28T16:50:20+00:00</updated>
<author>
<name>Lad Prabhakar</name>
<email>prabhakar.mahadev-lad.rj@bp.renesas.com</email>
</author>
<published>2021-12-24T14:29:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8f40bbf7dc01e4d54153d857fde2eefa9238127f'/>
<id>8f40bbf7dc01e4d54153d857fde2eefa9238127f</id>
<content type='text'>
[ Upstream commit 5b68061983471470d4109bac776145245f06bc09 ]

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq().

Signed-off-by: Lad Prabhakar &lt;prabhakar.mahadev-lad.rj@bp.renesas.com&gt;
Link: https://lore.kernel.org/r/20211224142917.6966-5-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
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 5b68061983471470d4109bac776145245f06bc09 ]

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq().

Signed-off-by: Lad Prabhakar &lt;prabhakar.mahadev-lad.rj@bp.renesas.com&gt;
Link: https://lore.kernel.org/r/20211224142917.6966-5-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: serial: meson: retrieve port FIFO size from DT</title>
<updated>2023-11-28T16:50:20+00:00</updated>
<author>
<name>Neil Armstrong</name>
<email>narmstrong@baylibre.com</email>
</author>
<published>2021-05-18T07:58:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a1113f2c9b2c69cf281e11b246996780127a95a9'/>
<id>a1113f2c9b2c69cf281e11b246996780127a95a9</id>
<content type='text'>
[ Upstream commit 27d44e05d7b85d9d4cfe0a3c0663ea49752ece93 ]

Now the DT bindings has a property to get the FIFO size for a particular port,
retrieve it and use to setup the FIFO interrupts threshold.

Reviewed-by: Kevin Hilman &lt;khilman@baylibre.com&gt;
Signed-off-by: Neil Armstrong &lt;narmstrong@baylibre.com&gt;
Link: https://lore.kernel.org/r/20210518075833.3736038-3-narmstrong@baylibre.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
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 27d44e05d7b85d9d4cfe0a3c0663ea49752ece93 ]

Now the DT bindings has a property to get the FIFO size for a particular port,
retrieve it and use to setup the FIFO interrupts threshold.

Reviewed-by: Kevin Hilman &lt;khilman@baylibre.com&gt;
Signed-off-by: Neil Armstrong &lt;narmstrong@baylibre.com&gt;
Link: https://lore.kernel.org/r/20210518075833.3736038-3-narmstrong@baylibre.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: meson: remove redundant initialization of variable id</title>
<updated>2023-11-28T16:50:20+00:00</updated>
<author>
<name>Colin Ian King</name>
<email>colin.king@canonical.com</email>
</author>
<published>2021-04-26T10:11:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=13391526d817b2d92c4b39ebc49c251ce51a5911'/>
<id>13391526d817b2d92c4b39ebc49c251ce51a5911</id>
<content type='text'>
[ Upstream commit 021212f5335229ed12e3d31f9b7d30bd3bb66f7d ]

The variable id being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed. Since id is just being used in a for-loop
inside a local scope, move the declaration of id to that scope.

Reviewed-by: Kevin Hilman &lt;khilman@baylibre.com&gt;
Reviewed-by: Martin Blumenstingl &lt;martin.blumenstingl@googlemail.com&gt;
Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Addresses-Coverity: ("Unused value")
Link: https://lore.kernel.org/r/20210426101106.9122-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
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 021212f5335229ed12e3d31f9b7d30bd3bb66f7d ]

The variable id being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed. Since id is just being used in a for-loop
inside a local scope, move the declaration of id to that scope.

Reviewed-by: Kevin Hilman &lt;khilman@baylibre.com&gt;
Reviewed-by: Martin Blumenstingl &lt;martin.blumenstingl@googlemail.com&gt;
Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Addresses-Coverity: ("Unused value")
Link: https://lore.kernel.org/r/20210426101106.9122-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 2a1d728f20ed ("tty: serial: meson: fix hard LOCKUP on crtscts mode")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: 8250: Add support for Intashield IS-100</title>
<updated>2023-11-08T10:23:43+00:00</updated>
<author>
<name>Cameron Williams</name>
<email>cang1@live.co.uk</email>
</author>
<published>2023-10-20T16:03:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8b0ecf2167a05d24f153efd7cf31a76dbb32fdda'/>
<id>8b0ecf2167a05d24f153efd7cf31a76dbb32fdda</id>
<content type='text'>
commit 4d994e3cf1b541ff32dfb03fbbc60eea68f9645b upstream.

Add support for the Intashield IS-100 1 port serial card.

Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB7899A0E0CDAA505AF5A874CDC4DBA@DU0PR02MB7899.eurprd02.prod.outlook.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 4d994e3cf1b541ff32dfb03fbbc60eea68f9645b upstream.

Add support for the Intashield IS-100 1 port serial card.

Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB7899A0E0CDAA505AF5A874CDC4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: 8250: Add support for Brainboxes UP cards</title>
<updated>2023-11-08T10:23:43+00:00</updated>
<author>
<name>Cameron Williams</name>
<email>cang1@live.co.uk</email>
</author>
<published>2023-10-20T16:03:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6dd5561b23854e3506516b63fea9e3ab98d1b4c0'/>
<id>6dd5561b23854e3506516b63fea9e3ab98d1b4c0</id>
<content type='text'>
commit 2c6fec1e1532f15350be7e14ba6b88a39d289fe4 upstream.

Add support for the Brainboxes UP (powered PCI) range of
cards, namely UP-189, UP-200, UP-869 and UP-880.

Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB7899B5B59FF3D8587E88C117C4DBA@DU0PR02MB7899.eurprd02.prod.outlook.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 2c6fec1e1532f15350be7e14ba6b88a39d289fe4 upstream.

Add support for the Brainboxes UP (powered PCI) range of
cards, namely UP-189, UP-200, UP-869 and UP-880.

Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB7899B5B59FF3D8587E88C117C4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: 8250: Add support for additional Brainboxes UC cards</title>
<updated>2023-11-08T10:23:43+00:00</updated>
<author>
<name>Cameron Williams</name>
<email>cang1@live.co.uk</email>
</author>
<published>2023-10-20T16:03:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=03145e0ff8ab13cb1babc2b1984d29bdba9265d4'/>
<id>03145e0ff8ab13cb1babc2b1984d29bdba9265d4</id>
<content type='text'>
commit c563db486db7d245c0e2f319443417ae8e692f7f upstream.

Add device IDs for some more Brainboxes UC cards, namely
UC-235/UC-246, UC-253/UC-734, UC-302, UC-313, UC-346, UC-357,
UC-607 and UC-836.

Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB789969998A6C3FAFCD95C85DC4DBA@DU0PR02MB7899.eurprd02.prod.outlook.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 c563db486db7d245c0e2f319443417ae8e692f7f upstream.

Add device IDs for some more Brainboxes UC cards, namely
UC-235/UC-246, UC-253/UC-734, UC-302, UC-313, UC-346, UC-357,
UC-607 and UC-836.

Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB789969998A6C3FAFCD95C85DC4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: 8250: Remove UC-257 and UC-431</title>
<updated>2023-11-08T10:23:43+00:00</updated>
<author>
<name>Cameron Williams</name>
<email>cang1@live.co.uk</email>
</author>
<published>2023-10-20T16:03:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5a6471372f9b28c72625af346d60137e8b3e7ee8'/>
<id>5a6471372f9b28c72625af346d60137e8b3e7ee8</id>
<content type='text'>
commit 33092fb3af51deb80849e90a17bada44bbcde6b3 upstream.

The UC-257 is a serial + LPT card, so remove it from this driver.
A patch has been submitted to add it to parport_serial instead.

Additionaly, the UC-431 does not use this card ID, only the UC-420
does. The 431 is a 3-port card and there is no generic 3-port configuration
available, so remove reference to it from this driver.

Fixes: 152d1afa834c ("tty: Add support for Brainboxes UC cards.")
Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB78995ADF7394C74AD4CF3357C4DBA@DU0PR02MB7899.eurprd02.prod.outlook.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 33092fb3af51deb80849e90a17bada44bbcde6b3 upstream.

The UC-257 is a serial + LPT card, so remove it from this driver.
A patch has been submitted to add it to parport_serial instead.

Additionaly, the UC-431 does not use this card ID, only the UC-420
does. The 431 is a 3-port card and there is no generic 3-port configuration
available, so remove reference to it from this driver.

Fixes: 152d1afa834c ("tty: Add support for Brainboxes UC cards.")
Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Link: https://lore.kernel.org/r/DU0PR02MB78995ADF7394C74AD4CF3357C4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250_port: Check IRQ data before use</title>
<updated>2023-10-10T19:46:41+00:00</updated>
<author>
<name>Andy Shevchenko</name>
<email>andriy.shevchenko@linux.intel.com</email>
</author>
<published>2023-08-31T22:25:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bf3c728e3692cc6d998874f0f27d433117348742'/>
<id>bf3c728e3692cc6d998874f0f27d433117348742</id>
<content type='text'>
commit cce7fc8b29961b64fadb1ce398dc5ff32a79643b upstream.

In case the leaf driver wants to use IRQ polling (irq = 0) and
IIR register shows that an interrupt happened in the 8250 hardware
the IRQ data can be NULL. In such a case we need to skip the wake
event as we came to this path from the timer interrupt and quite
likely system is already awake.

Without this fix we have got an Oops:

    serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A
    ...
    BUG: kernel NULL pointer dereference, address: 0000000000000010
    RIP: 0010:serial8250_handle_irq+0x7c/0x240
    Call Trace:
     ? serial8250_handle_irq+0x7c/0x240
     ? __pfx_serial8250_timeout+0x10/0x10

Fixes: 0ba9e3a13c6a ("serial: 8250: Add missing wakeup event reporting")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Link: https://lore.kernel.org/r/20230831222555.614426-1-andriy.shevchenko@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 cce7fc8b29961b64fadb1ce398dc5ff32a79643b upstream.

In case the leaf driver wants to use IRQ polling (irq = 0) and
IIR register shows that an interrupt happened in the 8250 hardware
the IRQ data can be NULL. In such a case we need to skip the wake
event as we came to this path from the timer interrupt and quite
likely system is already awake.

Without this fix we have got an Oops:

    serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A
    ...
    BUG: kernel NULL pointer dereference, address: 0000000000000010
    RIP: 0010:serial8250_handle_irq+0x7c/0x240
    Call Trace:
     ? serial8250_handle_irq+0x7c/0x240
     ? __pfx_serial8250_timeout+0x10/0x10

Fixes: 0ba9e3a13c6a ("serial: 8250: Add missing wakeup event reporting")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Link: https://lore.kernel.org/r/20230831222555.614426-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: cpm_uart: Avoid suspicious locking</title>
<updated>2023-09-23T09:00:05+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2023-08-03T13:56:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=44d72e9edd1b355683f35c218a9bcf485c421171'/>
<id>44d72e9edd1b355683f35c218a9bcf485c421171</id>
<content type='text'>
[ Upstream commit 36ef11d311f405e55ad8e848c19b212ff71ef536 ]

  CHECK   drivers/tty/serial/cpm_uart/cpm_uart_core.c
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1271:39: warning: context imbalance in 'cpm_uart_console_write' - unexpected unlock

Allthough 'nolock' is not expected to change, sparse find the following
form suspicious:

	if (unlikely(nolock)) {
		local_irq_save(flags);
	} else {
		spin_lock_irqsave(&amp;pinfo-&gt;port.lock, flags);
	}

	cpm_uart_early_write(pinfo, s, count, true);

	if (unlikely(nolock)) {
		local_irq_restore(flags);
	} else {
		spin_unlock_irqrestore(&amp;pinfo-&gt;port.lock, flags);
	}

Rewrite it a more obvious form:

	if (unlikely(oops_in_progress)) {
		local_irq_save(flags);
		cpm_uart_early_write(pinfo, s, count, true);
		local_irq_restore(flags);
	} else {
		spin_lock_irqsave(&amp;pinfo-&gt;port.lock, flags);
		cpm_uart_early_write(pinfo, s, count, true);
		spin_unlock_irqrestore(&amp;pinfo-&gt;port.lock, flags);
	}

Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Link: https://lore.kernel.org/r/f7da5cdc9287960185829cfef681a7d8614efa1f.1691068700.git.christophe.leroy@csgroup.eu
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 36ef11d311f405e55ad8e848c19b212ff71ef536 ]

  CHECK   drivers/tty/serial/cpm_uart/cpm_uart_core.c
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1271:39: warning: context imbalance in 'cpm_uart_console_write' - unexpected unlock

Allthough 'nolock' is not expected to change, sparse find the following
form suspicious:

	if (unlikely(nolock)) {
		local_irq_save(flags);
	} else {
		spin_lock_irqsave(&amp;pinfo-&gt;port.lock, flags);
	}

	cpm_uart_early_write(pinfo, s, count, true);

	if (unlikely(nolock)) {
		local_irq_restore(flags);
	} else {
		spin_unlock_irqrestore(&amp;pinfo-&gt;port.lock, flags);
	}

Rewrite it a more obvious form:

	if (unlikely(oops_in_progress)) {
		local_irq_save(flags);
		cpm_uart_early_write(pinfo, s, count, true);
		local_irq_restore(flags);
	} else {
		spin_lock_irqsave(&amp;pinfo-&gt;port.lock, flags);
		cpm_uart_early_write(pinfo, s, count, true);
		spin_unlock_irqrestore(&amp;pinfo-&gt;port.lock, flags);
	}

Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Link: https://lore.kernel.org/r/f7da5cdc9287960185829cfef681a7d8614efa1f.1691068700.git.christophe.leroy@csgroup.eu
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>
</feed>
