<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/net, branch v5.4.96</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ibmvnic: Ensure that CRQ entry read are correctly ordered</title>
<updated>2021-02-07T14:35:46+00:00</updated>
<author>
<name>Lijun Pan</name>
<email>ljp@linux.ibm.com</email>
</author>
<published>2021-01-28T01:34:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5e8776df14fa8b88b00ba833f6947c88fec95570'/>
<id>5e8776df14fa8b88b00ba833f6947c88fec95570</id>
<content type='text'>
commit e41aec79e62fa50f940cf222d1e9577f14e149dc upstream.

Ensure that received Command-Response Queue (CRQ) entries are
properly read in order by the driver. dma_rmb barrier has
been added before accessing the CRQ descriptor to ensure
the entire descriptor is read before processing.

Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: Lijun Pan &lt;ljp@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20210128013442.88319-1-ljp@linux.ibm.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.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 e41aec79e62fa50f940cf222d1e9577f14e149dc upstream.

Ensure that received Command-Response Queue (CRQ) entries are
properly read in order by the driver. dma_rmb barrier has
been added before accessing the CRQ descriptor to ensure
the entire descriptor is read before processing.

Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: Lijun Pan &lt;ljp@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20210128013442.88319-1-ljp@linux.ibm.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: dsa: bcm_sf2: put device node before return</title>
<updated>2021-02-07T14:35:46+00:00</updated>
<author>
<name>Pan Bian</name>
<email>bianpan2016@163.com</email>
</author>
<published>2021-01-21T12:33:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9edebe46010c2b50b0d54ac859f666a43ea6e274'/>
<id>9edebe46010c2b50b0d54ac859f666a43ea6e274</id>
<content type='text'>
commit cf3c46631e1637582f517a574c77cd6c05793817 upstream.

Put the device node dn before return error code on failure path.

Fixes: 461cd1b03e32 ("net: dsa: bcm_sf2: Register our slave MDIO bus")
Signed-off-by: Pan Bian &lt;bianpan2016@163.com&gt;
Link: https://lore.kernel.org/r/20210121123343.26330-1-bianpan2016@163.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.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 cf3c46631e1637582f517a574c77cd6c05793817 upstream.

Put the device node dn before return error code on failure path.

Fixes: 461cd1b03e32 ("net: dsa: bcm_sf2: Register our slave MDIO bus")
Signed-off-by: Pan Bian &lt;bianpan2016@163.com&gt;
Link: https://lore.kernel.org/r/20210121123343.26330-1-bianpan2016@163.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>team: protect features update by RCU to avoid deadlock</title>
<updated>2021-02-03T22:26:02+00:00</updated>
<author>
<name>Ivan Vecera</name>
<email>ivecera@redhat.com</email>
</author>
<published>2021-01-25T07:44:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3e93b9efc3bb4f153d69a1779e1ffd2036106c83'/>
<id>3e93b9efc3bb4f153d69a1779e1ffd2036106c83</id>
<content type='text'>
commit f0947d0d21b219e03940b9be6628a43445c0de7a upstream.

Function __team_compute_features() is protected by team-&gt;lock
mutex when it is called from team_compute_features() used when
features of an underlying device is changed. This causes
a deadlock when NETDEV_FEAT_CHANGE notifier for underlying device
is fired due to change propagated from team driver (e.g. MTU
change). It's because callbacks like team_change_mtu() or
team_vlan_rx_{add,del}_vid() protect their port list traversal
by team-&gt;lock mutex.

Example (r8169 case where this driver disables TSO for certain MTU
values):
...
[ 6391.348202]  __mutex_lock.isra.6+0x2d0/0x4a0
[ 6391.358602]  team_device_event+0x9d/0x160 [team]
[ 6391.363756]  notifier_call_chain+0x47/0x70
[ 6391.368329]  netdev_update_features+0x56/0x60
[ 6391.373207]  rtl8169_change_mtu+0x14/0x50 [r8169]
[ 6391.378457]  dev_set_mtu_ext+0xe1/0x1d0
[ 6391.387022]  dev_set_mtu+0x52/0x90
[ 6391.390820]  team_change_mtu+0x64/0xf0 [team]
[ 6391.395683]  dev_set_mtu_ext+0xe1/0x1d0
[ 6391.399963]  do_setlink+0x231/0xf50
...

In fact team_compute_features() called from team_device_event()
does not need to be protected by team-&gt;lock mutex and rcu_read_lock()
is sufficient there for port list traversal.

Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device")
Cc: Saeed Mahameed &lt;saeed@kernel.org&gt;
Signed-off-by: Ivan Vecera &lt;ivecera@redhat.com&gt;
Reviewed-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Reviewed-by: Jiri Pirko &lt;jiri@nvidia.com&gt;
Link: https://lore.kernel.org/r/20210125074416.4056484-1-ivecera@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.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 f0947d0d21b219e03940b9be6628a43445c0de7a upstream.

Function __team_compute_features() is protected by team-&gt;lock
mutex when it is called from team_compute_features() used when
features of an underlying device is changed. This causes
a deadlock when NETDEV_FEAT_CHANGE notifier for underlying device
is fired due to change propagated from team driver (e.g. MTU
change). It's because callbacks like team_change_mtu() or
team_vlan_rx_{add,del}_vid() protect their port list traversal
by team-&gt;lock mutex.

Example (r8169 case where this driver disables TSO for certain MTU
values):
...
[ 6391.348202]  __mutex_lock.isra.6+0x2d0/0x4a0
[ 6391.358602]  team_device_event+0x9d/0x160 [team]
[ 6391.363756]  notifier_call_chain+0x47/0x70
[ 6391.368329]  netdev_update_features+0x56/0x60
[ 6391.373207]  rtl8169_change_mtu+0x14/0x50 [r8169]
[ 6391.378457]  dev_set_mtu_ext+0xe1/0x1d0
[ 6391.387022]  dev_set_mtu+0x52/0x90
[ 6391.390820]  team_change_mtu+0x64/0xf0 [team]
[ 6391.395683]  dev_set_mtu_ext+0xe1/0x1d0
[ 6391.399963]  do_setlink+0x231/0xf50
...

In fact team_compute_features() called from team_device_event()
does not need to be protected by team-&gt;lock mutex and rcu_read_lock()
is sufficient there for port list traversal.

Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device")
Cc: Saeed Mahameed &lt;saeed@kernel.org&gt;
Signed-off-by: Ivan Vecera &lt;ivecera@redhat.com&gt;
Reviewed-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Reviewed-by: Jiri Pirko &lt;jiri@nvidia.com&gt;
Link: https://lore.kernel.org/r/20210125074416.4056484-1-ivecera@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>can: dev: prevent potential information leak in can_fill_info()</title>
<updated>2021-02-03T22:26:01+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2021-01-21T06:08:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=64a4ec1850f779a233ad7d19dc11e340df0d7a37'/>
<id>64a4ec1850f779a233ad7d19dc11e340df0d7a37</id>
<content type='text'>
[ Upstream commit b552766c872f5b0d90323b24e4c9e8fa67486dd5 ]

The "bec" struct isn't necessarily always initialized. For example, the
mcp251xfd_get_berr_counter() function doesn't initialize anything if the
interface is down.

Fixes: 52c793f24054 ("can: netlink support for bus-error reporting and counters")
Link: https://lore.kernel.org/r/YAkaRdRJncsJO8Ve@mwanda
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&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 b552766c872f5b0d90323b24e4c9e8fa67486dd5 ]

The "bec" struct isn't necessarily always initialized. For example, the
mcp251xfd_get_berr_counter() function doesn't initialize anything if the
interface is down.

Fixes: 52c793f24054 ("can: netlink support for bus-error reporting and counters")
Link: https://lore.kernel.org/r/YAkaRdRJncsJO8Ve@mwanda
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/mlx5e: Reduce tc unsupported key print level</title>
<updated>2021-02-03T22:26:01+00:00</updated>
<author>
<name>Maor Dickman</name>
<email>maord@nvidia.com</email>
</author>
<published>2021-01-19T15:21:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4dc2395d8f14e94ecf5a178e8e000bcb74abb10c'/>
<id>4dc2395d8f14e94ecf5a178e8e000bcb74abb10c</id>
<content type='text'>
[ Upstream commit 48470a90a42a64dd2f70743a149894a292b356e0 ]

"Unsupported key used:" appears in kernel log when flows with
unsupported key are used, arp fields for example.

OpenVSwitch was changed to match on arp fields by default that
caused this warning to appear in kernel log for every arp rule, which
can be a lot.

Fix by lowering print level from warning to debug.

Fixes: e3a2b7ed018e ("net/mlx5e: Support offload cls_flower with drop action")
Signed-off-by: Maor Dickman &lt;maord@nvidia.com&gt;
Reviewed-by: Roi Dayan &lt;roid@nvidia.com&gt;
Reviewed-by: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.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 48470a90a42a64dd2f70743a149894a292b356e0 ]

"Unsupported key used:" appears in kernel log when flows with
unsupported key are used, arp fields for example.

OpenVSwitch was changed to match on arp fields by default that
caused this warning to appear in kernel log for every arp rule, which
can be a lot.

Fix by lowering print level from warning to debug.

Fixes: e3a2b7ed018e ("net/mlx5e: Support offload cls_flower with drop action")
Signed-off-by: Maor Dickman &lt;maord@nvidia.com&gt;
Reviewed-by: Roi Dayan &lt;roid@nvidia.com&gt;
Reviewed-by: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/mlx5e: E-switch, Fix rate calculation for overflow</title>
<updated>2021-02-03T22:26:00+00:00</updated>
<author>
<name>Parav Pandit</name>
<email>parav@nvidia.com</email>
</author>
<published>2021-01-12T14:13:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a66705277baface033cdadc32d0307621f85582c'/>
<id>a66705277baface033cdadc32d0307621f85582c</id>
<content type='text'>
[ Upstream commit 1fe3e3166b35240615ab7f8276af2bbf2e51f559 ]

rate_bytes_ps is a 64-bit field. It passed as 32-bit field to
apply_police_params(). Due to this when police rate is higher
than 4Gbps, 32-bit calculation ignores the carry. This results
in incorrect rate configurationn the device.

Fix it by performing 64-bit calculation.

Fixes: fcb64c0f5640 ("net/mlx5: E-Switch, add ingress rate support")
Signed-off-by: Parav Pandit &lt;parav@nvidia.com&gt;
Reviewed-by: Eli Cohen &lt;elic@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.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 1fe3e3166b35240615ab7f8276af2bbf2e51f559 ]

rate_bytes_ps is a 64-bit field. It passed as 32-bit field to
apply_police_params(). Due to this when police rate is higher
than 4Gbps, 32-bit calculation ignores the carry. This results
in incorrect rate configurationn the device.

Fix it by performing 64-bit calculation.

Fixes: fcb64c0f5640 ("net/mlx5: E-Switch, add ingress rate support")
Signed-off-by: Parav Pandit &lt;parav@nvidia.com&gt;
Reviewed-by: Eli Cohen &lt;elic@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/mlx5: Fix memory leak on flow table creation error flow</title>
<updated>2021-02-03T22:26:00+00:00</updated>
<author>
<name>Roi Dayan</name>
<email>roid@nvidia.com</email>
</author>
<published>2021-01-12T12:04:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dbc13deeec6a84b6ea749b2f16b3b3bff18e5689'/>
<id>dbc13deeec6a84b6ea749b2f16b3b3bff18e5689</id>
<content type='text'>
[ Upstream commit 487c6ef81eb98d0a43cb08be91b1fcc9b4250626 ]

When we create the ft object we also init rhltable in ft-&gt;fgs_hash.
So in error flow before kfree of ft we need to destroy that rhltable.

Fixes: 693c6883bbc4 ("net/mlx5: Add hash table for flow groups in flow table")
Signed-off-by: Roi Dayan &lt;roid@nvidia.com&gt;
Reviewed-by: Maor Dickman &lt;maord@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.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 487c6ef81eb98d0a43cb08be91b1fcc9b4250626 ]

When we create the ft object we also init rhltable in ft-&gt;fgs_hash.
So in error flow before kfree of ft we need to destroy that rhltable.

Fixes: 693c6883bbc4 ("net/mlx5: Add hash table for flow groups in flow table")
Signed-off-by: Roi Dayan &lt;roid@nvidia.com&gt;
Reviewed-by: Maor Dickman &lt;maord@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>igc: fix link speed advertising</title>
<updated>2021-02-03T22:26:00+00:00</updated>
<author>
<name>Corinna Vinschen</name>
<email>vinschen@redhat.com</email>
</author>
<published>2020-11-17T19:50:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=02ef126a002df6215b8f08140a77154b13691225'/>
<id>02ef126a002df6215b8f08140a77154b13691225</id>
<content type='text'>
[ Upstream commit 329a3678ec69962aa67c91397efbd46d36635f91 ]

Link speed advertising in igc has two problems:

- When setting the advertisement via ethtool, the link speed is converted
  to the legacy 32 bit representation for the intel PHY code.
  This inadvertently drops ETHTOOL_LINK_MODE_2500baseT_Full_BIT (being
  beyond bit 31).  As a result, any call to `ethtool -s ...' drops the
  2500Mbit/s link speed from the PHY settings.  Only reloading the driver
  alleviates that problem.

  Fix this by converting the ETHTOOL_LINK_MODE_2500baseT_Full_BIT to the
  Intel PHY ADVERTISE_2500_FULL bit explicitly.

- Rather than checking the actual PHY setting, the .get_link_ksettings
  function always fills link_modes.advertising with all link speeds
  the device is capable of.

  Fix this by checking the PHY autoneg_advertised settings and report
  only the actually advertised speeds up to ethtool.

Fixes: 8c5ad0dae93c ("igc: Add ethtool support")
Signed-off-by: Corinna Vinschen &lt;vinschen@redhat.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.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 329a3678ec69962aa67c91397efbd46d36635f91 ]

Link speed advertising in igc has two problems:

- When setting the advertisement via ethtool, the link speed is converted
  to the legacy 32 bit representation for the intel PHY code.
  This inadvertently drops ETHTOOL_LINK_MODE_2500baseT_Full_BIT (being
  beyond bit 31).  As a result, any call to `ethtool -s ...' drops the
  2500Mbit/s link speed from the PHY settings.  Only reloading the driver
  alleviates that problem.

  Fix this by converting the ETHTOOL_LINK_MODE_2500baseT_Full_BIT to the
  Intel PHY ADVERTISE_2500_FULL bit explicitly.

- Rather than checking the actual PHY setting, the .get_link_ksettings
  function always fills link_modes.advertising with all link speeds
  the device is capable of.

  Fix this by checking the PHY autoneg_advertised settings and report
  only the actually advertised speeds up to ethtool.

Fixes: 8c5ad0dae93c ("igc: Add ethtool support")
Signed-off-by: Corinna Vinschen &lt;vinschen@redhat.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i40e: acquire VSI pointer only after VF is initialized</title>
<updated>2021-02-03T22:26:00+00:00</updated>
<author>
<name>Stefan Assmann</name>
<email>sassmann@kpanic.de</email>
</author>
<published>2020-11-30T13:12:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=873d1a4740d65d965d9c9ec4d69bc28a2ef59f00'/>
<id>873d1a4740d65d965d9c9ec4d69bc28a2ef59f00</id>
<content type='text'>
[ Upstream commit 67a3c6b3cc40bb217c3ff947a55053151a00fea0 ]

This change simplifies the VF initialization check and also minimizes
the delay between acquiring the VSI pointer and using it. As known by
the commit being fixed, there is a risk of the VSI pointer getting
changed. Therefore minimize the delay between getting and using the
pointer.

Fixes: 9889707b06ac ("i40e: Fix crash caused by stress setting of VF MAC addresses")
Signed-off-by: Stefan Assmann &lt;sassmann@kpanic.de&gt;
Reviewed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Tested-by: Konrad Jankowski &lt;konrad0.jankowski@intel.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.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 67a3c6b3cc40bb217c3ff947a55053151a00fea0 ]

This change simplifies the VF initialization check and also minimizes
the delay between acquiring the VSI pointer and using it. As known by
the commit being fixed, there is a risk of the VSI pointer getting
changed. Therefore minimize the delay between getting and using the
pointer.

Fixes: 9889707b06ac ("i40e: Fix crash caused by stress setting of VF MAC addresses")
Signed-off-by: Stefan Assmann &lt;sassmann@kpanic.de&gt;
Reviewed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Tested-by: Konrad Jankowski &lt;konrad0.jankowski@intel.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iwlwifi: pcie: reschedule in long-running memory reads</title>
<updated>2021-02-03T22:26:00+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2021-01-15T11:05:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=46c67a4c1a76b4da673c414a7ce124950b04dafd'/>
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[ Upstream commit 3d372c4edfd4dffb7dea71c6b096fb414782b776 ]

If we spin for a long time in memory reads that (for some reason in
hardware) take a long time, then we'll eventually get messages such
as

  watchdog: BUG: soft lockup - CPU#2 stuck for 24s! [kworker/2:2:272]

This is because the reading really does take a very long time, and
we don't schedule, so we're hogging the CPU with this task, at least
if CONFIG_PREEMPT is not set, e.g. with CONFIG_PREEMPT_VOLUNTARY=y.

Previously I misinterpreted the situation and thought that this was
only going to happen if we had interrupts disabled, and then fixed
this (which is good anyway, however), but that didn't always help;
looking at it again now I realized that the spin unlock will only
reschedule if CONFIG_PREEMPT is used.

In order to avoid this issue, change the code to cond_resched() if
we've been spinning for too long here.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Fixes: 04516706bb99 ("iwlwifi: pcie: limit memory read spin time")
Signed-off-by: Luca Coelho &lt;luciano.coelho@intel.com&gt;
Signed-off-by: Kalle Valo &lt;kvalo@codeaurora.org&gt;
Link: https://lore.kernel.org/r/iwlwifi.20210115130253.217a9d6a6a12.If964cb582ab0aaa94e81c4ff3b279eaafda0fd3f@changeid
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
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[ Upstream commit 3d372c4edfd4dffb7dea71c6b096fb414782b776 ]

If we spin for a long time in memory reads that (for some reason in
hardware) take a long time, then we'll eventually get messages such
as

  watchdog: BUG: soft lockup - CPU#2 stuck for 24s! [kworker/2:2:272]

This is because the reading really does take a very long time, and
we don't schedule, so we're hogging the CPU with this task, at least
if CONFIG_PREEMPT is not set, e.g. with CONFIG_PREEMPT_VOLUNTARY=y.

Previously I misinterpreted the situation and thought that this was
only going to happen if we had interrupts disabled, and then fixed
this (which is good anyway, however), but that didn't always help;
looking at it again now I realized that the spin unlock will only
reschedule if CONFIG_PREEMPT is used.

In order to avoid this issue, change the code to cond_resched() if
we've been spinning for too long here.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Fixes: 04516706bb99 ("iwlwifi: pcie: limit memory read spin time")
Signed-off-by: Luca Coelho &lt;luciano.coelho@intel.com&gt;
Signed-off-by: Kalle Valo &lt;kvalo@codeaurora.org&gt;
Link: https://lore.kernel.org/r/iwlwifi.20210115130253.217a9d6a6a12.If964cb582ab0aaa94e81c4ff3b279eaafda0fd3f@changeid
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
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