<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/alpha, branch v5.4.232</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>exit: Add and use make_task_dead.</title>
<updated>2023-02-06T06:52:49+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2023-02-02T04:42:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9a18c9c8336fff473a2b72707bd14a52298417b8'/>
<id>9a18c9c8336fff473a2b72707bd14a52298417b8</id>
<content type='text'>
commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 upstream.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: Eric Biggers &lt;ebiggers@google.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>
commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 upstream.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alpha: fix syscall entry in !AUDUT_SYSCALL case</title>
<updated>2023-01-18T10:40:53+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2021-09-18T22:18:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f0ff6c60bc82c87e130f7fba8e322a96c12f5d1e'/>
<id>f0ff6c60bc82c87e130f7fba8e322a96c12f5d1e</id>
<content type='text'>
[ Upstream commit f7b2431a6d22f7a91c567708e071dfcd6d66db14 ]

We only want to take the slow path if SYSCALL_TRACE or SYSCALL_AUDIT is
set; on !AUDIT_SYSCALL configs the current tree hits it whenever _any_
thread flag (including NEED_RESCHED, NOTIFY_SIGNAL, etc.) happens to
be set.

Fixes: a9302e843944 "alpha: Enable system-call auditing support"
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&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 f7b2431a6d22f7a91c567708e071dfcd6d66db14 ]

We only want to take the slow path if SYSCALL_TRACE or SYSCALL_AUDIT is
set; on !AUDIT_SYSCALL configs the current tree hits it whenever _any_
thread flag (including NEED_RESCHED, NOTIFY_SIGNAL, etc.) happens to
be set.

Fixes: a9302e843944 "alpha: Enable system-call auditing support"
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: the rest, stop using tty_schedule_flip()</title>
<updated>2022-07-29T15:14:19+00:00</updated>
<author>
<name>Jiri Slaby</name>
<email>jslaby@suse.cz</email>
</author>
<published>2021-11-22T11:16:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f20912215c9ca3403b2dbbbeac26e98663defb67'/>
<id>f20912215c9ca3403b2dbbbeac26e98663defb67</id>
<content type='text'>
commit b68b914494df4f79b4e9b58953110574af1cb7a2 upstream.

Since commit a9c3f68f3cd8d (tty: Fix low_latency BUG) in 2014,
tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). We are
going to remove the latter (as it is used less), so call the former in
the rest of the users.

Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: William Hubbs &lt;w.d.hubbs@gmail.com&gt;
Cc: Chris Brannon &lt;chris@the-brannons.com&gt;
Cc: Kirk Reiser &lt;kirk@reisers.ca&gt;
Cc: Samuel Thibault &lt;samuel.thibault@ens-lyon.org&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Reviewed-by: Johan Hovold &lt;johan@kernel.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
Link: https://lore.kernel.org/r/20211122111648.30379-3-jslaby@suse.cz
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 b68b914494df4f79b4e9b58953110574af1cb7a2 upstream.

Since commit a9c3f68f3cd8d (tty: Fix low_latency BUG) in 2014,
tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). We are
going to remove the latter (as it is used less), so call the former in
the rest of the users.

Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: William Hubbs &lt;w.d.hubbs@gmail.com&gt;
Cc: Chris Brannon &lt;chris@the-brannons.com&gt;
Cc: Kirk Reiser &lt;kirk@reisers.ca&gt;
Cc: Samuel Thibault &lt;samuel.thibault@ens-lyon.org&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Reviewed-by: Johan Hovold &lt;johan@kernel.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
Link: https://lore.kernel.org/r/20211122111648.30379-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alpha: define get_cycles macro for arch-override</title>
<updated>2022-06-22T12:11:14+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-04-23T19:11:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=10455a367c33cf015363d610926d579d73e15a48'/>
<id>10455a367c33cf015363d610926d579d73e15a48</id>
<content type='text'>
commit 1097710bc9660e1e588cf2186a35db3d95c4d258 upstream.

Alpha defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().

Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Acked-by: Matt Turner &lt;mattst88@gmail.com&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&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 1097710bc9660e1e588cf2186a35db3d95c4d258 upstream.

Alpha defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().

Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Acked-by: Matt Turner &lt;mattst88@gmail.com&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alpha: Declare virt_to_phys and virt_to_bus parameter as pointer to volatile</title>
<updated>2021-09-30T08:09:26+00:00</updated>
<author>
<name>Guenter Roeck</name>
<email>linux@roeck-us.net</email>
</author>
<published>2021-09-09T05:00:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fa56f2c987c752e365324c26cc7fc0255a370d7f'/>
<id>fa56f2c987c752e365324c26cc7fc0255a370d7f</id>
<content type='text'>
[ Upstream commit 35a3f4ef0ab543daa1725b0c963eb8c05e3376f8 ]

Some drivers pass a pointer to volatile data to virt_to_bus() and
virt_to_phys(), and that works fine.  One exception is alpha.  This
results in a number of compile errors such as

  drivers/net/wan/lmc/lmc_main.c: In function 'lmc_softreset':
  drivers/net/wan/lmc/lmc_main.c:1782:50: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

  drivers/atm/ambassador.c: In function 'do_loader_command':
  drivers/atm/ambassador.c:1747:58: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

Declare the parameter of virt_to_phys and virt_to_bus as pointer to
volatile to fix the problem.

Signed-off-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.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 35a3f4ef0ab543daa1725b0c963eb8c05e3376f8 ]

Some drivers pass a pointer to volatile data to virt_to_bus() and
virt_to_phys(), and that works fine.  One exception is alpha.  This
results in a number of compile errors such as

  drivers/net/wan/lmc/lmc_main.c: In function 'lmc_softreset':
  drivers/net/wan/lmc/lmc_main.c:1782:50: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

  drivers/atm/ambassador.c: In function 'do_loader_command':
  drivers/atm/ambassador.c:1747:58: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

Declare the parameter of virt_to_phys and virt_to_bus as pointer to
volatile to fix the problem.

Signed-off-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alpha: Send stop IPI to send to online CPUs</title>
<updated>2021-08-12T11:21:05+00:00</updated>
<author>
<name>Prarit Bhargava</name>
<email>prarit@redhat.com</email>
</author>
<published>2021-01-05T15:16:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=742e85fa9e802bf611ce645caa1c39bdd0a1d2a8'/>
<id>742e85fa9e802bf611ce645caa1c39bdd0a1d2a8</id>
<content type='text'>
[ Upstream commit caace6ca4e06f09413fb8f8a63319594cfb7d47d ]

This issue was noticed while debugging a shutdown issue where some
secondary CPUs are not being shutdown correctly.  A fix for that [1] requires
that secondary cpus be offlined using the cpu_online_mask so that the
stop operation is a no-op if CPU HOTPLUG is disabled.  I, like the author in
[1] looked at the architectures and found that alpha is one of two
architectures that executes smp_send_stop() on all possible CPUs.

On alpha, smp_send_stop() sends an IPI to all possible CPUs but only needs
to send them to online CPUs.

Send the stop IPI to only the online CPUs.

[1] https://lkml.org/lkml/2020/1/10/250

Signed-off-by: Prarit Bhargava &lt;prarit@redhat.com&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Signed-off-by: Matt Turner &lt;mattst88@gmail.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 caace6ca4e06f09413fb8f8a63319594cfb7d47d ]

This issue was noticed while debugging a shutdown issue where some
secondary CPUs are not being shutdown correctly.  A fix for that [1] requires
that secondary cpus be offlined using the cpu_online_mask so that the
stop operation is a no-op if CPU HOTPLUG is disabled.  I, like the author in
[1] looked at the architectures and found that alpha is one of two
architectures that executes smp_send_stop() on all possible CPUs.

On alpha, smp_send_stop() sends an IPI to all possible CPUs but only needs
to send them to online CPUs.

Send the stop IPI to only the online CPUs.

[1] https://lkml.org/lkml/2020/1/10/250

Signed-off-by: Prarit Bhargava &lt;prarit@redhat.com&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Signed-off-by: Matt Turner &lt;mattst88@gmail.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alpha: fix annotation of io{read,write}{16,32}be()</title>
<updated>2020-08-26T08:40:58+00:00</updated>
<author>
<name>Luc Van Oostenryck</name>
<email>luc.vanoostenryck@gmail.com</email>
</author>
<published>2020-08-12T01:33:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e4f952b031c11d801b0eb4985a95f37adb5171d8'/>
<id>e4f952b031c11d801b0eb4985a95f37adb5171d8</id>
<content type='text'>
[ Upstream commit bd72866b8da499e60633ff28f8a4f6e09ca78efe ]

These accessors must be used to read/write a big-endian bus.  The value
returned or written is native-endian.

However, these accessors are defined using be{16,32}_to_cpu() or
cpu_to_be{16,32}() to make the endian conversion but these expect a
__be{16,32} when none is present.  Keeping them would need a force cast
that would solve nothing at all.

So, do the conversion using swab{16,32}, like done in asm-generic for
similar situations.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Luc Van Oostenryck &lt;luc.vanoostenryck@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Stephen Boyd &lt;sboyd@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Link: http://lkml.kernel.org/r/20200622114232.80039-1-luc.vanoostenryck@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.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 bd72866b8da499e60633ff28f8a4f6e09ca78efe ]

These accessors must be used to read/write a big-endian bus.  The value
returned or written is native-endian.

However, these accessors are defined using be{16,32}_to_cpu() or
cpu_to_be{16,32}() to make the endian conversion but these expect a
__be{16,32} when none is present.  Keeping them would need a force cast
that would solve nothing at all.

So, do the conversion using swab{16,32}, like done in asm-generic for
similar situations.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Luc Van Oostenryck &lt;luc.vanoostenryck@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Stephen Boyd &lt;sboyd@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Link: http://lkml.kernel.org/r/20200622114232.80039-1-luc.vanoostenryck@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: sr: remove references to BLK_DEV_SR_VENDOR, leave it enabled</title>
<updated>2020-07-22T07:32:57+00:00</updated>
<author>
<name>Diego Elio Pettenò</name>
<email>flameeyes@flameeyes.com</email>
</author>
<published>2020-02-23T19:11:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=69fbdbb4fa0cbaf95b7f464d62f34cb4c3b2cab9'/>
<id>69fbdbb4fa0cbaf95b7f464d62f34cb4c3b2cab9</id>
<content type='text'>
[ Upstream commit 679b2ec8e060ca7a90441aff5e7d384720a41b76 ]

This kernel configuration is basically enabling/disabling sr driver quirks
detection. While these quirks are for fairly rare devices (very old CD
burners, and a glucometer), the additional detection of these models is a
very minimal amount of code.

The logic behind the quirks is always built into the sr driver.

This also removes the config from all the defconfig files that are enabling
this already.

Link: https://lore.kernel.org/r/20200223191144.726-1-flameeyes@flameeyes.com
Reviewed-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Diego Elio Pettenò &lt;flameeyes@flameeyes.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.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 679b2ec8e060ca7a90441aff5e7d384720a41b76 ]

This kernel configuration is basically enabling/disabling sr driver quirks
detection. While these quirks are for fairly rare devices (very old CD
burners, and a glucometer), the additional detection of these models is a
very minimal amount of code.

The logic behind the quirks is always built into the sr driver.

This also removes the config from all the defconfig files that are enabling
this already.

Link: https://lore.kernel.org/r/20200223191144.726-1-flameeyes@flameeyes.com
Reviewed-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Diego Elio Pettenò &lt;flameeyes@flameeyes.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alpha: fix memory barriers so that they conform to the specification</title>
<updated>2020-06-22T07:31:21+00:00</updated>
<author>
<name>Mikulas Patocka</name>
<email>mpatocka@redhat.com</email>
</author>
<published>2020-05-26T14:47:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c81e34c4346f9d3ba21a3c6f7491a6e7e330a7ee'/>
<id>c81e34c4346f9d3ba21a3c6f7491a6e7e330a7ee</id>
<content type='text'>
commit 54505a1e2083fc54cbe8779b97479f969cd30a00 upstream.

The commits cd0e00c10672 and 92d7223a7423 broke boot on the Alpha Avanti
platform. The patches move memory barriers after a write before the write.
The result is that if there's iowrite followed by ioread, there is no
barrier between them.

The Alpha architecture allows reordering of the accesses to the I/O space,
and the missing barrier between write and read causes hang with serial
port and real time clock.

This patch makes barriers confiorm to the specification.

1. We add mb() before readX_relaxed and writeX_relaxed -
   memory-barriers.txt claims that these functions must be ordered w.r.t.
   each other. Alpha doesn't order them, so we need an explicit barrier.
2. We add mb() before reads from the I/O space - so that if there's a
   write followed by a read, there should be a barrier between them.

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Fixes: cd0e00c10672 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering")
Fixes: 92d7223a7423 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering #2")
Cc: stable@vger.kernel.org      # v4.17+
Acked-by: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Reviewed-by: Maciej W. Rozycki &lt;macro@linux-mips.org&gt;
Signed-off-by: Matt Turner &lt;mattst88@gmail.com&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 54505a1e2083fc54cbe8779b97479f969cd30a00 upstream.

The commits cd0e00c10672 and 92d7223a7423 broke boot on the Alpha Avanti
platform. The patches move memory barriers after a write before the write.
The result is that if there's iowrite followed by ioread, there is no
barrier between them.

The Alpha architecture allows reordering of the accesses to the I/O space,
and the missing barrier between write and read causes hang with serial
port and real time clock.

This patch makes barriers confiorm to the specification.

1. We add mb() before readX_relaxed and writeX_relaxed -
   memory-barriers.txt claims that these functions must be ordered w.r.t.
   each other. Alpha doesn't order them, so we need an explicit barrier.
2. We add mb() before reads from the I/O space - so that if there's a
   write followed by a read, there should be a barrier between them.

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Fixes: cd0e00c10672 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering")
Fixes: 92d7223a7423 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering #2")
Cc: stable@vger.kernel.org      # v4.17+
Acked-by: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Reviewed-by: Maciej W. Rozycki &lt;macro@linux-mips.org&gt;
Signed-off-by: Matt Turner &lt;mattst88@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>mm: introduce MADV_PAGEOUT</title>
<updated>2019-09-26T00:51:41+00:00</updated>
<author>
<name>Minchan Kim</name>
<email>minchan@kernel.org</email>
</author>
<published>2019-09-25T23:49:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1a4e58cce84ee88129d5d49c064bd2852b481357'/>
<id>1a4e58cce84ee88129d5d49c064bd2852b481357</id>
<content type='text'>
When a process expects no accesses to a certain memory range for a long
time, it could hint kernel that the pages can be reclaimed instantly but
data should be preserved for future use.  This could reduce workingset
eviction so it ends up increasing performance.

This patch introduces the new MADV_PAGEOUT hint to madvise(2) syscall.
MADV_PAGEOUT can be used by a process to mark a memory range as not
expected to be used for a long time so that kernel reclaims *any LRU*
pages instantly.  The hint can help kernel in deciding which pages to
evict proactively.

A note: It doesn't apply SWAP_CLUSTER_MAX LRU page isolation limit
intentionally because it's automatically bounded by PMD size.  If PMD
size(e.g., 256) makes some trouble, we could fix it later by limit it to
SWAP_CLUSTER_MAX[1].

- man-page material

MADV_PAGEOUT (since Linux x.x)

Do not expect access in the near future so pages in the specified
regions could be reclaimed instantly regardless of memory pressure.
Thus, access in the range after successful operation could cause
major page fault but never lose the up-to-date contents unlike
MADV_DONTNEED. Pages belonging to a shared mapping are only processed
if a write access is allowed for the calling process.

MADV_PAGEOUT cannot be applied to locked pages, Huge TLB pages, or
VM_PFNMAP pages.

[1] https://lore.kernel.org/lkml/20190710194719.GS29695@dhcp22.suse.cz/

[minchan@kernel.org: clear PG_active on MADV_PAGEOUT]
  Link: http://lkml.kernel.org/r/20190802200643.GA181880@google.com
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-5-minchan@kernel.org
Signed-off-by: Minchan Kim &lt;minchan@kernel.org&gt;
Reported-by: kbuild test robot &lt;lkp@intel.com&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: James E.J. Bottomley &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Daniel Colascione &lt;dancol@google.com&gt;
Cc: Dave Hansen &lt;dave.hansen@intel.com&gt;
Cc: Hillf Danton &lt;hdanton@sina.com&gt;
Cc: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Oleksandr Natalenko &lt;oleksandr@redhat.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Cc: Sonny Rao &lt;sonnyrao@google.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Tim Murray &lt;timmurray@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When a process expects no accesses to a certain memory range for a long
time, it could hint kernel that the pages can be reclaimed instantly but
data should be preserved for future use.  This could reduce workingset
eviction so it ends up increasing performance.

This patch introduces the new MADV_PAGEOUT hint to madvise(2) syscall.
MADV_PAGEOUT can be used by a process to mark a memory range as not
expected to be used for a long time so that kernel reclaims *any LRU*
pages instantly.  The hint can help kernel in deciding which pages to
evict proactively.

A note: It doesn't apply SWAP_CLUSTER_MAX LRU page isolation limit
intentionally because it's automatically bounded by PMD size.  If PMD
size(e.g., 256) makes some trouble, we could fix it later by limit it to
SWAP_CLUSTER_MAX[1].

- man-page material

MADV_PAGEOUT (since Linux x.x)

Do not expect access in the near future so pages in the specified
regions could be reclaimed instantly regardless of memory pressure.
Thus, access in the range after successful operation could cause
major page fault but never lose the up-to-date contents unlike
MADV_DONTNEED. Pages belonging to a shared mapping are only processed
if a write access is allowed for the calling process.

MADV_PAGEOUT cannot be applied to locked pages, Huge TLB pages, or
VM_PFNMAP pages.

[1] https://lore.kernel.org/lkml/20190710194719.GS29695@dhcp22.suse.cz/

[minchan@kernel.org: clear PG_active on MADV_PAGEOUT]
  Link: http://lkml.kernel.org/r/20190802200643.GA181880@google.com
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-5-minchan@kernel.org
Signed-off-by: Minchan Kim &lt;minchan@kernel.org&gt;
Reported-by: kbuild test robot &lt;lkp@intel.com&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: James E.J. Bottomley &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Daniel Colascione &lt;dancol@google.com&gt;
Cc: Dave Hansen &lt;dave.hansen@intel.com&gt;
Cc: Hillf Danton &lt;hdanton@sina.com&gt;
Cc: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Oleksandr Natalenko &lt;oleksandr@redhat.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Cc: Sonny Rao &lt;sonnyrao@google.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Tim Murray &lt;timmurray@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
