<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/tty/serial, branch v5.11-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'for-linus' of git://github.com/openrisc/linux</title>
<updated>2020-12-17T21:41:27+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-12-17T21:41:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0c6c887835b59c10602add88057c9c06f265effe'/>
<id>0c6c887835b59c10602add88057c9c06f265effe</id>
<content type='text'>
Pull OpenRISC updates from Stafford Horne:

 - New drivers and OpenRISC support for the LiteX platform

 - A bug fix to support userspace gdb debugging

 - Fixes one compile issue with blk-iocost

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: add local64.h to fix blk-iocost build
  openrisc: fix trap for debugger breakpoint signalling
  openrisc: add support for LiteX
  drivers/tty/serial: add LiteUART driver
  dt-bindings: serial: document LiteUART bindings
  drivers/soc/litex: add LiteX SoC Controller driver
  dt-bindings: soc: document LiteX SoC Controller bindings
  dt-bindings: vendor: add vendor prefix for LiteX
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull OpenRISC updates from Stafford Horne:

 - New drivers and OpenRISC support for the LiteX platform

 - A bug fix to support userspace gdb debugging

 - Fixes one compile issue with blk-iocost

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: add local64.h to fix blk-iocost build
  openrisc: fix trap for debugger breakpoint signalling
  openrisc: add support for LiteX
  drivers/tty/serial: add LiteUART driver
  dt-bindings: serial: document LiteUART bindings
  drivers/soc/litex: add LiteX SoC Controller driver
  dt-bindings: soc: document LiteX SoC Controller bindings
  dt-bindings: vendor: add vendor prefix for LiteX
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'tty-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty</title>
<updated>2020-12-15T21:57:14+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-12-15T21:57:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=157f809894f3cf8e62b4011915a00398603215c9'/>
<id>157f809894f3cf8e62b4011915a00398603215c9</id>
<content type='text'>
Pull tty / serial updates from Greg KH:
 "Here is the "large" set of tty and serial patches for 5.11-rc1.

  Nothing major at all, some cleanups and some driver removals, always a
  nice sign:

   - build warning cleanups

   - vt locking and logic unwinding and cleanups

   - tiny serial driver fixes and updates

   - removal of the synclink serial driver as it's no longer needed

   - removal of dead termiox code

  All of this has been in linux-next for a while with no reported issues"

* tag 'tty-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (89 commits)
  serial: 8250_pci: Drop bogus __refdata annotation
  tty: serial: meson: enable console as module
  serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access
  serial: imx: Move imx_uart_probe_dt() content into probe()
  serial: imx: Remove unneeded of_device_get_match_data() NULL check
  tty: Fix whitespace inconsistencies in vt_io_ioctl
  serial_core: Check for port state when tty is in error state
  dt-bindings: serial: Update DT binding docs to support SiFive FU740 SoC
  tty: use const parameters in port-flag accessors
  tty: use assign_bit() in port-flag accessors
  earlycon: drop semicolon from earlycon macro
  tty: Remove dead termiox code
  tty/serial/imx: Enable TXEN bit in imx_poll_init().
  tty : serial: jsm: Fixed file by adding spacing
  tty: serial: uartlite: Support probe deferral
  earlycon: simplify earlycon-table implementation
  tty: serial: bcm63xx: lower driver dependencies
  serial: mxs-auart: Remove unneeded platform_device_id
  serial: 8250-mtk: Fix reference leak in mtk8250_probe
  serial: imx: Remove unused .id_table support
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull tty / serial updates from Greg KH:
 "Here is the "large" set of tty and serial patches for 5.11-rc1.

  Nothing major at all, some cleanups and some driver removals, always a
  nice sign:

   - build warning cleanups

   - vt locking and logic unwinding and cleanups

   - tiny serial driver fixes and updates

   - removal of the synclink serial driver as it's no longer needed

   - removal of dead termiox code

  All of this has been in linux-next for a while with no reported issues"

* tag 'tty-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (89 commits)
  serial: 8250_pci: Drop bogus __refdata annotation
  tty: serial: meson: enable console as module
  serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access
  serial: imx: Move imx_uart_probe_dt() content into probe()
  serial: imx: Remove unneeded of_device_get_match_data() NULL check
  tty: Fix whitespace inconsistencies in vt_io_ioctl
  serial_core: Check for port state when tty is in error state
  dt-bindings: serial: Update DT binding docs to support SiFive FU740 SoC
  tty: use const parameters in port-flag accessors
  tty: use assign_bit() in port-flag accessors
  earlycon: drop semicolon from earlycon macro
  tty: Remove dead termiox code
  tty/serial/imx: Enable TXEN bit in imx_poll_init().
  tty : serial: jsm: Fixed file by adding spacing
  tty: serial: uartlite: Support probe deferral
  earlycon: simplify earlycon-table implementation
  tty: serial: bcm63xx: lower driver dependencies
  serial: mxs-auart: Remove unneeded platform_device_id
  serial: 8250-mtk: Fix reference leak in mtk8250_probe
  serial: imx: Remove unused .id_table support
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'm68k-for-v5.11-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k</title>
<updated>2020-12-15T00:20:48+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-12-15T00:20:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0b03beface02d519693edb8020f9811c67d5c88f'/>
<id>0b03beface02d519693edb8020f9811c67d5c88f</id>
<content type='text'>
Pull m68k updates from Geert Uytterhoeven:

 - fix WARNING splat in pmac_zilog driver

 - fix ADB input device regression

 - assume maintainership for adb-iop and via-macii

 - minor fixes and improvements

 - defconfig updates

* tag 'm68k-for-v5.11-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  MAINTAINERS: Update m68k Mac entry
  macintosh/adb-iop: Send correct poll command
  macintosh/adb-iop: Always wait for reply message from IOP
  m68k: Fix WARNING splat in pmac_zilog driver
  m68k: Add a missing ELF_DETAILS in link script
  m68k: Drop redundant NOTES in link script
  m68k: mac: Update Kconfig help
  m68k: mac: Remove redundant VIA register writes
  m68k: mac: Remove dead code
  m68k: mac: Refactor iop_preinit() and iop_init()
  m68k: defconfig: Enable KUnit tests
  m68k: defconfig: Update defconfigs for v5.10-rc1
  m68k: Remove unused mach_max_dma_address
  m68k: Avoid xchg() warning
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull m68k updates from Geert Uytterhoeven:

 - fix WARNING splat in pmac_zilog driver

 - fix ADB input device regression

 - assume maintainership for adb-iop and via-macii

 - minor fixes and improvements

 - defconfig updates

* tag 'm68k-for-v5.11-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  MAINTAINERS: Update m68k Mac entry
  macintosh/adb-iop: Send correct poll command
  macintosh/adb-iop: Always wait for reply message from IOP
  m68k: Fix WARNING splat in pmac_zilog driver
  m68k: Add a missing ELF_DETAILS in link script
  m68k: Drop redundant NOTES in link script
  m68k: mac: Update Kconfig help
  m68k: mac: Remove redundant VIA register writes
  m68k: mac: Remove dead code
  m68k: mac: Refactor iop_preinit() and iop_init()
  m68k: defconfig: Enable KUnit tests
  m68k: defconfig: Update defconfigs for v5.10-rc1
  m68k: Remove unused mach_max_dma_address
  m68k: Avoid xchg() warning
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250_pci: Drop bogus __refdata annotation</title>
<updated>2020-12-11T16:17:50+00:00</updated>
<author>
<name>Geert Uytterhoeven</name>
<email>geert+renesas@glider.be</email>
</author>
<published>2020-12-11T13:39:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c3ae3dc896fab5524f9b20f547e72e4b892d8d8e'/>
<id>c3ae3dc896fab5524f9b20f547e72e4b892d8d8e</id>
<content type='text'>
Since commit d73dfc6a4199e0e3 ("serial: 8250_pci: remove __devexit
usage") in v3.9, the 8250/16550 PCI serial driver no longer has any code
or data located in initmem, hence there is no need to annotate the
pci_serial_quirks structure with __refdata.  Drop the annotation, to
avoid suppressing future section warnings.

Signed-off-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Link: https://lore.kernel.org/r/20201211133907.2970460-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since commit d73dfc6a4199e0e3 ("serial: 8250_pci: remove __devexit
usage") in v3.9, the 8250/16550 PCI serial driver no longer has any code
or data located in initmem, hence there is no need to annotate the
pci_serial_quirks structure with __refdata.  Drop the annotation, to
avoid suppressing future section warnings.

Signed-off-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Link: https://lore.kernel.org/r/20201211133907.2970460-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: serial: meson: enable console as module</title>
<updated>2020-12-11T16:14:22+00:00</updated>
<author>
<name>Kevin Hilman</name>
<email>khilman@baylibre.com</email>
</author>
<published>2020-12-11T00:57:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=87a0b9f98ac5a14aae5b0fbcff930a240b24f827'/>
<id>87a0b9f98ac5a14aae5b0fbcff930a240b24f827</id>
<content type='text'>
Enable serial driver to be built as a module.  To do so, init the
console support on driver/module load instead of using
console_initcall().

Signed-off-by: Kevin Hilman &lt;khilman@baylibre.com&gt;
Link: https://lore.kernel.org/r/20201211005744.12855-1-khilman@baylibre.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>
Enable serial driver to be built as a module.  To do so, init the
console support on driver/module load instead of using
console_initcall().

Signed-off-by: Kevin Hilman &lt;khilman@baylibre.com&gt;
Link: https://lore.kernel.org/r/20201211005744.12855-1-khilman@baylibre.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access</title>
<updated>2020-12-10T15:27:47+00:00</updated>
<author>
<name>Alexander Sverdlin</name>
<email>alexander.sverdlin@gmail.com</email>
</author>
<published>2020-12-10T05:52:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d96f04d347e4011977abdbb4da5d8f303ebd26f8'/>
<id>d96f04d347e4011977abdbb4da5d8f303ebd26f8</id>
<content type='text'>
It has been observed that once per 300-1300 port openings the first
transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared
as "e" on the wire). It only happened if single byte has been transmitted
right after port open, which means, DMA is not used for this transfer and
the corruption never happened afterwards.

Therefore I've carefully re-read the MDR1 errata (link below), which says
"when accessing the MDR1 registers that causes a dummy under-run condition
that will freeze the UART in IrDA transmission. In UART mode, this may
corrupt the transferred data". Strictly speaking,
omap_8250_mdr1_errataset() performs a read access and if the value is the
same as should be written, exits without errata-recommended FIFO reset.

A brief check of the serial_omap_mdr1_errataset() from the competing
omap-serial driver showed it has no read access of MDR1. After removing the
read access from omap_8250_mdr1_errataset() the data corruption never
happened any more.

Link: https://www.ti.com/lit/er/sprz360i/sprz360i.pdf
Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Sverdlin &lt;alexander.sverdlin@gmail.com&gt;
Link: https://lore.kernel.org/r/20201210055257.1053028-1-alexander.sverdlin@gmail.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>
It has been observed that once per 300-1300 port openings the first
transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared
as "e" on the wire). It only happened if single byte has been transmitted
right after port open, which means, DMA is not used for this transfer and
the corruption never happened afterwards.

Therefore I've carefully re-read the MDR1 errata (link below), which says
"when accessing the MDR1 registers that causes a dummy under-run condition
that will freeze the UART in IrDA transmission. In UART mode, this may
corrupt the transferred data". Strictly speaking,
omap_8250_mdr1_errataset() performs a read access and if the value is the
same as should be written, exits without errata-recommended FIFO reset.

A brief check of the serial_omap_mdr1_errataset() from the competing
omap-serial driver showed it has no read access of MDR1. After removing the
read access from omap_8250_mdr1_errataset() the data corruption never
happened any more.

Link: https://www.ti.com/lit/er/sprz360i/sprz360i.pdf
Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Sverdlin &lt;alexander.sverdlin@gmail.com&gt;
Link: https://lore.kernel.org/r/20201210055257.1053028-1-alexander.sverdlin@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: imx: Move imx_uart_probe_dt() content into probe()</title>
<updated>2020-12-10T15:24:52+00:00</updated>
<author>
<name>Fabio Estevam</name>
<email>festevam@gmail.com</email>
</author>
<published>2020-12-09T21:47:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4661f46e50f2d658592f665be1f1f999ff647d3c'/>
<id>4661f46e50f2d658592f665be1f1f999ff647d3c</id>
<content type='text'>
Now that the driver only probes via devicetree, we can move the
content of imx_uart_probe_dt() directly into imx_uart_probe() to
make the code simpler.

Suggested-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Signed-off-by: Fabio Estevam &lt;festevam@gmail.com&gt;
Link: https://lore.kernel.org/r/20201209214712.15247-1-festevam@gmail.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>
Now that the driver only probes via devicetree, we can move the
content of imx_uart_probe_dt() directly into imx_uart_probe() to
make the code simpler.

Suggested-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Signed-off-by: Fabio Estevam &lt;festevam@gmail.com&gt;
Link: https://lore.kernel.org/r/20201209214712.15247-1-festevam@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: imx: Remove unneeded of_device_get_match_data() NULL check</title>
<updated>2020-12-09T18:48:10+00:00</updated>
<author>
<name>Fabio Estevam</name>
<email>festevam@gmail.com</email>
</author>
<published>2020-11-26T12:46:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=603012f78a3f5cb2e7f529b8e318321117a9cf7c'/>
<id>603012f78a3f5cb2e7f529b8e318321117a9cf7c</id>
<content type='text'>
Since 5.10-rc1 i.MX is a devicetree-only platform and the NULL check on
of_device_get_match_data() is no longer needed.

This check was only needed when this driver supported both DT and non-DT
platforms.

Remove the unneeded of_device_get_match_data() NULL check.

Signed-off-by: Fabio Estevam &lt;festevam@gmail.com&gt;
Link: https://lore.kernel.org/r/20201126124643.3371-1-festevam@gmail.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>
Since 5.10-rc1 i.MX is a devicetree-only platform and the NULL check on
of_device_get_match_data() is no longer needed.

This check was only needed when this driver supported both DT and non-DT
platforms.

Remove the unneeded of_device_get_match_data() NULL check.

Signed-off-by: Fabio Estevam &lt;festevam@gmail.com&gt;
Link: https://lore.kernel.org/r/20201126124643.3371-1-festevam@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial_core: Check for port state when tty is in error state</title>
<updated>2020-12-09T14:34:37+00:00</updated>
<author>
<name>Alexey Kardashevskiy</name>
<email>aik@ozlabs.ru</email>
</author>
<published>2020-12-03T05:58:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2f70e49ed860020f5abae4f7015018ebc10e1f0e'/>
<id>2f70e49ed860020f5abae4f7015018ebc10e1f0e</id>
<content type='text'>
At the moment opening a serial device node (such as /dev/ttyS3)
succeeds even if there is no actual serial device behind it.
Reading/writing/ioctls fail as expected because the uart port is not
initialized (the type is PORT_UNKNOWN) and the TTY_IO_ERROR error state
bit is set fot the tty.

However setting line discipline does not have these checks
8250_port.c (8250 is the default choice made by univ8250_console_init()).
As the result of PORT_UNKNOWN, uart_port::iobase is NULL which
a platform translates onto some address accessing which produces a crash
like below.

This adds tty_port_initialized() to uart_set_ldisc() to prevent the crash.

Found by syzkaller.

Signed-off-by: Alexey Kardashevskiy &lt;aik@ozlabs.ru&gt;
Link: https://lore.kernel.org/r/20201203055834.45838-1-aik@ozlabs.ru
Cc: stable &lt;stable@vger.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>
At the moment opening a serial device node (such as /dev/ttyS3)
succeeds even if there is no actual serial device behind it.
Reading/writing/ioctls fail as expected because the uart port is not
initialized (the type is PORT_UNKNOWN) and the TTY_IO_ERROR error state
bit is set fot the tty.

However setting line discipline does not have these checks
8250_port.c (8250 is the default choice made by univ8250_console_init()).
As the result of PORT_UNKNOWN, uart_port::iobase is NULL which
a platform translates onto some address accessing which produces a crash
like below.

This adds tty_port_initialized() to uart_set_ldisc() to prevent the crash.

Found by syzkaller.

Signed-off-by: Alexey Kardashevskiy &lt;aik@ozlabs.ru&gt;
Link: https://lore.kernel.org/r/20201203055834.45838-1-aik@ozlabs.ru
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty/serial/imx: Enable TXEN bit in imx_poll_init().</title>
<updated>2020-12-04T15:54:20+00:00</updated>
<author>
<name>Mingrui Ren</name>
<email>jiladahe1997@gmail.com</email>
</author>
<published>2020-12-02T07:25:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=aef1b6a27970607721a618a0b990716ca8dbbf97'/>
<id>aef1b6a27970607721a618a0b990716ca8dbbf97</id>
<content type='text'>
As described in Documentation, poll_init() is called by kgdb to initialize
hardware which supports both poll_put_char() and poll_get_char().

It's necessary to enable TXEN bit, otherwise, it will cause hardware fault
and kernel panic when calling imx_poll_put_char().

Generally, if use /dev/ttymxc0 as kgdb console as well as system
console, ttymxc0 is initialized early by system console which does enable
TXEN bit.But when use /dev/ttymxc1 as kgbd console, ttymxc1 is only
initialized by imx_poll_init() cannot enable the TXEN bit, which will
cause kernel panic.

Signed-off-by: Mingrui Ren &lt;jiladahe1997@gmail.com&gt;
Link: https://lore.kernel.org/r/20201202072543.151-1-972931182@qq.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
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<pre>
As described in Documentation, poll_init() is called by kgdb to initialize
hardware which supports both poll_put_char() and poll_get_char().

It's necessary to enable TXEN bit, otherwise, it will cause hardware fault
and kernel panic when calling imx_poll_put_char().

Generally, if use /dev/ttymxc0 as kgdb console as well as system
console, ttymxc0 is initialized early by system console which does enable
TXEN bit.But when use /dev/ttymxc1 as kgbd console, ttymxc1 is only
initialized by imx_poll_init() cannot enable the TXEN bit, which will
cause kernel panic.

Signed-off-by: Mingrui Ren &lt;jiladahe1997@gmail.com&gt;
Link: https://lore.kernel.org/r/20201202072543.151-1-972931182@qq.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
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