<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/char, branch v4.4.211</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>hwrng: omap3-rom - Call clk_disable_unprepare() on exit only if not idled</title>
<updated>2020-01-04T12:34:09+00:00</updated>
<author>
<name>Tony Lindgren</name>
<email>tony@atomide.com</email>
</author>
<published>2019-09-14T21:02:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c6b766dde980641d6d2948dce25f1039be7776ba'/>
<id>c6b766dde980641d6d2948dce25f1039be7776ba</id>
<content type='text'>
[ Upstream commit eaecce12f5f0d2c35d278e41e1bc4522393861ab ]

When unloading omap3-rom-rng, we'll get the following:

WARNING: CPU: 0 PID: 100 at drivers/clk/clk.c:948 clk_core_disable

This is because the clock may be already disabled by omap3_rom_rng_idle().
Let's fix the issue by checking for rng_idle on exit.

Cc: Aaro Koskinen &lt;aaro.koskinen@iki.fi&gt;
Cc: Adam Ford &lt;aford173@gmail.com&gt;
Cc: Pali Rohár &lt;pali.rohar@gmail.com&gt;
Cc: Sebastian Reichel &lt;sre@kernel.org&gt;
Cc: Tero Kristo &lt;t-kristo@ti.com&gt;
Fixes: 1c6b7c2108bd ("hwrng: OMAP3 ROM Random Number Generator support")
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&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 eaecce12f5f0d2c35d278e41e1bc4522393861ab ]

When unloading omap3-rom-rng, we'll get the following:

WARNING: CPU: 0 PID: 100 at drivers/clk/clk.c:948 clk_core_disable

This is because the clock may be already disabled by omap3_rom_rng_idle().
Let's fix the issue by checking for rng_idle on exit.

Cc: Aaro Koskinen &lt;aaro.koskinen@iki.fi&gt;
Cc: Adam Ford &lt;aford173@gmail.com&gt;
Cc: Pali Rohár &lt;pali.rohar@gmail.com&gt;
Cc: Sebastian Reichel &lt;sre@kernel.org&gt;
Cc: Tero Kristo &lt;t-kristo@ti.com&gt;
Fixes: 1c6b7c2108bd ("hwrng: OMAP3 ROM Random Number Generator support")
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hwrng: stm32 - fix unbalanced pm_runtime_enable</title>
<updated>2019-12-05T14:27:18+00:00</updated>
<author>
<name>Lionel Debieve</name>
<email>lionel.debieve@st.com</email>
</author>
<published>2019-04-01T10:30:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ee168df277fef44597ce8c36311a986b068eb877'/>
<id>ee168df277fef44597ce8c36311a986b068eb877</id>
<content type='text'>
commit af0d4442dd6813de6e77309063beb064fa8e89ae upstream.

No remove function implemented yet in the driver.
Without remove function, the pm_runtime implementation
complains when removing and probing again the driver.

Signed-off-by: Lionel Debieve &lt;lionel.debieve@st.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
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 af0d4442dd6813de6e77309063beb064fa8e89ae upstream.

No remove function implemented yet in the driver.
Without remove function, the pm_runtime implementation
complains when removing and probing again the driver.

Signed-off-by: Lionel Debieve &lt;lionel.debieve@st.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>virtio_console: move removal code</title>
<updated>2019-11-28T17:26:23+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2018-04-20T17:51:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b12818d70879ffa0ac5f40672ef502445c1a3368'/>
<id>b12818d70879ffa0ac5f40672ef502445c1a3368</id>
<content type='text'>
[ Upstream commit aa44ec867030a72e8aa127977e37dec551d8df19 ]

Will make it reusable for error handling.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&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 aa44ec867030a72e8aa127977e37dec551d8df19 ]

Will make it reusable for error handling.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>virtio_console: drop custom control queue cleanup</title>
<updated>2019-11-28T17:26:23+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2018-04-20T17:49:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fa3c628897e62909ea10a8a12de3b9d4492669ed'/>
<id>fa3c628897e62909ea10a8a12de3b9d4492669ed</id>
<content type='text'>
[ Upstream commit 61a8950c5c5708cf2068b29ffde94e454e528208 ]

We now cleanup all VQs on device removal - no need
to handle the control VQ specially.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&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 61a8950c5c5708cf2068b29ffde94e454e528208 ]

We now cleanup all VQs on device removal - no need
to handle the control VQ specially.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>virtio_console: fix uninitialized variable use</title>
<updated>2019-11-28T17:26:22+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2017-03-29T20:22:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ba9e2c1190a6b193ba2256a6810c8204ee5d08c3'/>
<id>ba9e2c1190a6b193ba2256a6810c8204ee5d08c3</id>
<content type='text'>
[ Upstream commit 2055997f983c6db7b5c3940ce5f8f822657d5bc3 ]

We try to disable callbacks on c_ivq even without multiport
even though that vq is not initialized in this configuration.

Fixes: c743d09dbd01 ("virtio: console: Disable callbacks for virtqueues at start of S4 freeze")
Suggested-by: Mike Galbraith &lt;efault@gmx.de&gt;
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&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 2055997f983c6db7b5c3940ce5f8f822657d5bc3 ]

We try to disable callbacks on c_ivq even without multiport
even though that vq is not initialized in this configuration.

Fixes: c743d09dbd01 ("virtio: console: Disable callbacks for virtqueues at start of S4 freeze")
Suggested-by: Mike Galbraith &lt;efault@gmx.de&gt;
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>virtio_console: allocate inbufs in add_port() only if it is needed</title>
<updated>2019-11-28T17:26:22+00:00</updated>
<author>
<name>Laurent Vivier</name>
<email>lvivier@redhat.com</email>
</author>
<published>2019-11-14T12:25:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=abdd31f3744ef8b6c7aa4178ed7fec3070ef29d3'/>
<id>abdd31f3744ef8b6c7aa4178ed7fec3070ef29d3</id>
<content type='text'>
[ Upstream commit d791cfcbf98191122af70b053a21075cb450d119 ]

When we hot unplug a virtserialport and then try to hot plug again,
it fails:

(qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait
(qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\
                  chardev=serial0,id=serial0,name=serial0
(qemu) device_del serial0
(qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\
                  chardev=serial0,id=serial0,name=serial0
kernel error:
  virtio-ports vport2p2: Error allocating inbufs
qemu error:
  virtio-serial-bus: Guest failure in adding port 2 for device \
                     virtio-serial0.0

This happens because buffers for the in_vq are allocated when the port is
added but are not released when the port is unplugged.

They are only released when virtconsole is removed (see a7a69ec0d8e4)

To avoid the problem and to be symmetric, we could allocate all the buffers
in init_vqs() as they are released in remove_vqs(), but it sounds like
a waste of memory.

Rather than that, this patch changes add_port() logic to ignore ENOSPC
error in fill_queue(), which means queue has already been filled.

Fixes: a7a69ec0d8e4 ("virtio_console: free buffers after reset")
Cc: mst@redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Laurent Vivier &lt;lvivier@redhat.com&gt;
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&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 d791cfcbf98191122af70b053a21075cb450d119 ]

When we hot unplug a virtserialport and then try to hot plug again,
it fails:

(qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait
(qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\
                  chardev=serial0,id=serial0,name=serial0
(qemu) device_del serial0
(qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\
                  chardev=serial0,id=serial0,name=serial0
kernel error:
  virtio-ports vport2p2: Error allocating inbufs
qemu error:
  virtio-serial-bus: Guest failure in adding port 2 for device \
                     virtio-serial0.0

This happens because buffers for the in_vq are allocated when the port is
added but are not released when the port is unplugged.

They are only released when virtconsole is removed (see a7a69ec0d8e4)

To avoid the problem and to be symmetric, we could allocate all the buffers
in init_vqs() as they are released in remove_vqs(), but it sounds like
a waste of memory.

Rather than that, this patch changes add_port() logic to ignore ENOSPC
error in fill_queue(), which means queue has already been filled.

Fixes: a7a69ec0d8e4 ("virtio_console: free buffers after reset")
Cc: mst@redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Laurent Vivier &lt;lvivier@redhat.com&gt;
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>virtio_console: don't tie bufs to a vq</title>
<updated>2019-11-28T17:26:21+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2018-04-20T16:54:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=809ff9a14bdea2c70440f1f4479d29a179ea6682'/>
<id>809ff9a14bdea2c70440f1f4479d29a179ea6682</id>
<content type='text'>
[ Upstream commit 2855b33514d290c51d52d94e25d3ef942cd4d578 ]

an allocated buffer doesn't need to be tied to a vq -
only vq-&gt;vdev is ever used. Pass the function the
just what it needs - the vdev.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&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 2855b33514d290c51d52d94e25d3ef942cd4d578 ]

an allocated buffer doesn't need to be tied to a vq -
only vq-&gt;vdev is ever used. Pass the function the
just what it needs - the vdev.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>virtio_console: reset on out of memory</title>
<updated>2019-11-28T17:26:21+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2018-04-20T18:00:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4cad8c2d8f8b50638dc5da357b5f2e42b5860f19'/>
<id>4cad8c2d8f8b50638dc5da357b5f2e42b5860f19</id>
<content type='text'>
[ Upstream commit 5c60300d68da32ca77f7f978039dc72bfc78b06b ]

When out of memory and we can't add ctrl vq buffers,
probe fails. Unfortunately the error handling is
out of spec: it calls del_vqs without bothering
to reset the device first.

To fix, call the full cleanup function in this case.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&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 5c60300d68da32ca77f7f978039dc72bfc78b06b ]

When out of memory and we can't add ctrl vq buffers,
probe fails. Unfortunately the error handling is
out of spec: it calls del_vqs without bothering
to reset the device first.

To fix, call the full cleanup function in this case.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipmi_si: Only schedule continuously in the thread in maintenance mode</title>
<updated>2019-10-07T19:00:59+00:00</updated>
<author>
<name>Corey Minyard</name>
<email>cminyard@mvista.com</email>
</author>
<published>2019-08-02T12:31:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d9e87b4415c7a81986f440e32f628325f79ae533'/>
<id>d9e87b4415c7a81986f440e32f628325f79ae533</id>
<content type='text'>
[ Upstream commit 340ff31ab00bca5c15915e70ad9ada3030c98cf8 ]

ipmi_thread() uses back-to-back schedule() to poll for command
completion which, on some machines, can push up CPU consumption and
heavily tax the scheduler locks leading to noticeable overall
performance degradation.

This was originally added so firmware updates through IPMI would
complete in a timely manner.  But we can't kill the scheduler
locks for that one use case.

Instead, only run schedule() continuously in maintenance mode,
where firmware updates should run.

Signed-off-by: Corey Minyard &lt;cminyard@mvista.com&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 340ff31ab00bca5c15915e70ad9ada3030c98cf8 ]

ipmi_thread() uses back-to-back schedule() to poll for command
completion which, on some machines, can push up CPU consumption and
heavily tax the scheduler locks leading to noticeable overall
performance degradation.

This was originally added so firmware updates through IPMI would
complete in a timely manner.  But we can't kill the scheduler
locks for that one use case.

Instead, only run schedule() continuously in maintenance mode,
where firmware updates should run.

Signed-off-by: Corey Minyard &lt;cminyard@mvista.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hwrng: core - don't wait on add_early_randomness()</title>
<updated>2019-10-05T10:27:55+00:00</updated>
<author>
<name>Laurent Vivier</name>
<email>lvivier@redhat.com</email>
</author>
<published>2019-09-17T09:54:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c648d4350015ab238c0b1ba35616adfb72f5d76b'/>
<id>c648d4350015ab238c0b1ba35616adfb72f5d76b</id>
<content type='text'>
commit 78887832e76541f77169a24ac238fccb51059b63 upstream.

add_early_randomness() is called by hwrng_register() when the
hardware is added. If this hardware and its module are present
at boot, and if there is no data available the boot hangs until
data are available and can't be interrupted.

For instance, in the case of virtio-rng, in some cases the host can be
not able to provide enough entropy for all the guests.

We can have two easy ways to reproduce the problem but they rely on
misconfiguration of the hypervisor or the egd daemon:

- if virtio-rng device is configured to connect to the egd daemon of the
host but when the virtio-rng driver asks for data the daemon is not
connected,

- if virtio-rng device is configured to connect to the egd daemon of the
host but the egd daemon doesn't provide data.

The guest kernel will hang at boot until the virtio-rng driver provides
enough data.

To avoid that, call rng_get_data() in non-blocking mode (wait=0)
from add_early_randomness().

Signed-off-by: Laurent Vivier &lt;lvivier@redhat.com&gt;
Fixes: d9e797261933 ("hwrng: add randomness to system from rng...")
Cc: &lt;stable@vger.kernel.org&gt;
Reviewed-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
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 78887832e76541f77169a24ac238fccb51059b63 upstream.

add_early_randomness() is called by hwrng_register() when the
hardware is added. If this hardware and its module are present
at boot, and if there is no data available the boot hangs until
data are available and can't be interrupted.

For instance, in the case of virtio-rng, in some cases the host can be
not able to provide enough entropy for all the guests.

We can have two easy ways to reproduce the problem but they rely on
misconfiguration of the hypervisor or the egd daemon:

- if virtio-rng device is configured to connect to the egd daemon of the
host but when the virtio-rng driver asks for data the daemon is not
connected,

- if virtio-rng device is configured to connect to the egd daemon of the
host but the egd daemon doesn't provide data.

The guest kernel will hang at boot until the virtio-rng driver provides
enough data.

To avoid that, call rng_get_data() in non-blocking mode (wait=0)
from add_early_randomness().

Signed-off-by: Laurent Vivier &lt;lvivier@redhat.com&gt;
Fixes: d9e797261933 ("hwrng: add randomness to system from rng...")
Cc: &lt;stable@vger.kernel.org&gt;
Reviewed-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
