<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/m68k/include/asm, branch linux-3.12.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>m68k: Fix ndelay() macro</title>
<updated>2017-01-26T16:22:20+00:00</updated>
<author>
<name>Boris Brezillon</name>
<email>boris.brezillon@free-electrons.com</email>
</author>
<published>2016-10-28T15:12:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=13e993f84eebae3672f94509cb858a7eae139aa0'/>
<id>13e993f84eebae3672f94509cb858a7eae139aa0</id>
<content type='text'>
commit 7e251bb21ae08ca2e4fb28cc0981fac2685a8efa upstream.

The current ndelay() macro definition has an extra semi-colon at the
end of the line thus leading to a compilation error when ndelay is used
in a conditional block without curly braces like this one:

	if (cond)
		ndelay(t);
	else
		...

which, after the preprocessor pass gives:

	if (cond)
		m68k_ndelay(t);;
	else
		...

thus leading to the following gcc error:

	error: 'else' without a previous 'if'

Remove this extra semi-colon.

Signed-off-by: Boris Brezillon &lt;boris.brezillon@free-electrons.com&gt;
Fixes: c8ee038bd1488 ("m68k: Implement ndelay() based on the existing udelay() logic")
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 7e251bb21ae08ca2e4fb28cc0981fac2685a8efa upstream.

The current ndelay() macro definition has an extra semi-colon at the
end of the line thus leading to a compilation error when ndelay is used
in a conditional block without curly braces like this one:

	if (cond)
		ndelay(t);
	else
		...

which, after the preprocessor pass gives:

	if (cond)
		m68k_ndelay(t);;
	else
		...

thus leading to the following gcc error:

	error: 'else' without a previous 'if'

Remove this extra semi-colon.

Signed-off-by: Boris Brezillon &lt;boris.brezillon@free-electrons.com&gt;
Fixes: c8ee038bd1488 ("m68k: Implement ndelay() based on the existing udelay() logic")
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>m68k: Define asmlinkage_protect</title>
<updated>2015-10-28T15:38:07+00:00</updated>
<author>
<name>Andreas Schwab</name>
<email>schwab@linux-m68k.org</email>
</author>
<published>2015-09-23T21:12:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8e158ccecbb3278e6c35b3cc920578be56400432'/>
<id>8e158ccecbb3278e6c35b3cc920578be56400432</id>
<content type='text'>
commit 8474ba74193d302e8340dddd1e16c85cc4b98caf upstream.

Make sure the compiler does not modify arguments of syscall functions.
This can happen if the compiler generates a tailcall to another
function.  For example, without asmlinkage_protect sys_openat is compiled
into this function:

sys_openat:
	clr.l %d0
	move.w 18(%sp),%d0
	move.l %d0,16(%sp)
	jbra do_sys_open

Note how the fourth argument is modified in place, modifying the register
%d4 that gets restored from this stack slot when the function returns to
user-space.  The caller may expect the register to be unmodified across
system calls.

Signed-off-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8474ba74193d302e8340dddd1e16c85cc4b98caf upstream.

Make sure the compiler does not modify arguments of syscall functions.
This can happen if the compiler generates a tailcall to another
function.  For example, without asmlinkage_protect sys_openat is compiled
into this function:

sys_openat:
	clr.l %d0
	move.w 18(%sp),%d0
	move.l %d0,16(%sp)
	jbra do_sys_open

Note how the fourth argument is modified in place, modifying the register
%d4 that gets restored from this stack slot when the function returns to
user-space.  The caller may expect the register to be unmodified across
system calls.

Signed-off-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arch: Clean up asm/barrier.h implementations using asm-generic/barrier.h</title>
<updated>2015-10-28T15:37:39+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2013-11-06T13:57:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=35377f1656fdb8fba54c70eb4d27bf16356b1468'/>
<id>35377f1656fdb8fba54c70eb4d27bf16356b1468</id>
<content type='text'>
commit 93ea02bb84354370e51de803a9405f171f3edf88 upstream.

We're going to be adding a few new barrier primitives, and in order to
avoid endless duplication make more agressive use of
asm-generic/barrier.h.

Change the asm-generic/barrier.h such that it allows partial barrier
definitions and fills out the rest with defaults.

There are a few architectures (m32r, m68k) that could probably
do away with their barrier.h file entirely but are kept for now due to
their unconventional nop() implementation.

Suggested-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Reviewed-by: "Paul E. McKenney" &lt;paulmck@linux.vnet.ibm.com&gt;
Reviewed-by: Mathieu Desnoyers &lt;mathieu.desnoyers@polymtl.ca&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Michael Ellerman &lt;michael@ellerman.id.au&gt;
Cc: Michael Neuling &lt;mikey@neuling.org&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Victor Kaplansky &lt;VICTORK@il.ibm.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Link: http://lkml.kernel.org/r/20131213150640.846368594@infradead.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 93ea02bb84354370e51de803a9405f171f3edf88 upstream.

We're going to be adding a few new barrier primitives, and in order to
avoid endless duplication make more agressive use of
asm-generic/barrier.h.

Change the asm-generic/barrier.h such that it allows partial barrier
definitions and fills out the rest with defaults.

There are a few architectures (m32r, m68k) that could probably
do away with their barrier.h file entirely but are kept for now due to
their unconventional nop() implementation.

Suggested-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Reviewed-by: "Paul E. McKenney" &lt;paulmck@linux.vnet.ibm.com&gt;
Reviewed-by: Mathieu Desnoyers &lt;mathieu.desnoyers@polymtl.ca&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Michael Ellerman &lt;michael@ellerman.id.au&gt;
Cc: Michael Neuling &lt;mikey@neuling.org&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Victor Kaplansky &lt;VICTORK@il.ibm.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Link: http://lkml.kernel.org/r/20131213150640.846368594@infradead.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu</title>
<updated>2013-09-09T16:04:46+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-09-09T16:04:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=833ae40b517a99e05fc4aea399e71f633f3348d2'/>
<id>833ae40b517a99e05fc4aea399e71f633f3348d2</id>
<content type='text'>
Pull m68knommu fixes from Greg Ungerer:
 "Just a small collection of cleanups and fixes this time, no big
  changes.  The most interresting are to make the m68k and m68knommu
  consistently use CONFIG_IOMAP, clean out some unused board config
  options and flush the cache on signal stack creation"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: remove 16 unused boards in Kconfig.machine
  m68k: define 'VM_DATA_DEFAULT_FLAGS' no matter whether has 'NOMMU' or not
  m68knommu: user generic iomap to support ioread*/iowrite*
  m68k/coldfire: flush cache when creating the signal stack frame
  m68knommu: Mark functions only called from setup_arch() __init
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull m68knommu fixes from Greg Ungerer:
 "Just a small collection of cleanups and fixes this time, no big
  changes.  The most interresting are to make the m68k and m68knommu
  consistently use CONFIG_IOMAP, clean out some unused board config
  options and flush the cache on signal stack creation"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: remove 16 unused boards in Kconfig.machine
  m68k: define 'VM_DATA_DEFAULT_FLAGS' no matter whether has 'NOMMU' or not
  m68knommu: user generic iomap to support ioread*/iowrite*
  m68k/coldfire: flush cache when creating the signal stack frame
  m68knommu: Mark functions only called from setup_arch() __init
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2013-09-04T16:36:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-09-04T16:36:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6832d9652f395f7d13003e3884942c40f52ac1fa'/>
<id>6832d9652f395f7d13003e3884942c40f52ac1fa</id>
<content type='text'>
Pull timers/nohz changes from Ingo Molnar:
 "It mostly contains fixes and full dynticks off-case optimizations, by
  Frederic Weisbecker"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  nohz: Include local CPU in full dynticks global kick
  nohz: Optimize full dynticks's sched hooks with static keys
  nohz: Optimize full dynticks state checks with static keys
  nohz: Rename a few state variables
  vtime: Always debug check snapshot source _before_ updating it
  vtime: Always scale generic vtime accounting results
  vtime: Optimize full dynticks accounting off case with static keys
  vtime: Describe overriden functions in dedicated arch headers
  m68k: hardirq_count() only need preempt_mask.h
  hardirq: Split preempt count mask definitions
  context_tracking: Split low level state headers
  vtime: Fix racy cputime delta update
  vtime: Remove a few unneeded generic vtime state checks
  context_tracking: User/kernel broundary cross trace events
  context_tracking: Optimize context switch off case with static keys
  context_tracking: Optimize guest APIs off case with static key
  context_tracking: Optimize main APIs off case with static key
  context_tracking: Ground setup for static key use
  context_tracking: Remove full dynticks' hacky dependency on wide context tracking
  nohz: Only enable context tracking on full dynticks CPUs
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull timers/nohz changes from Ingo Molnar:
 "It mostly contains fixes and full dynticks off-case optimizations, by
  Frederic Weisbecker"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  nohz: Include local CPU in full dynticks global kick
  nohz: Optimize full dynticks's sched hooks with static keys
  nohz: Optimize full dynticks state checks with static keys
  nohz: Rename a few state variables
  vtime: Always debug check snapshot source _before_ updating it
  vtime: Always scale generic vtime accounting results
  vtime: Optimize full dynticks accounting off case with static keys
  vtime: Describe overriden functions in dedicated arch headers
  m68k: hardirq_count() only need preempt_mask.h
  hardirq: Split preempt count mask definitions
  context_tracking: Split low level state headers
  vtime: Fix racy cputime delta update
  vtime: Remove a few unneeded generic vtime state checks
  context_tracking: User/kernel broundary cross trace events
  context_tracking: Optimize context switch off case with static keys
  context_tracking: Optimize guest APIs off case with static key
  context_tracking: Optimize main APIs off case with static key
  context_tracking: Ground setup for static key use
  context_tracking: Remove full dynticks' hacky dependency on wide context tracking
  nohz: Only enable context tracking on full dynticks CPUs
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>m68k: define 'VM_DATA_DEFAULT_FLAGS' no matter whether has 'NOMMU' or not</title>
<updated>2013-08-26T06:51:14+00:00</updated>
<author>
<name>Greg Ungerer</name>
<email>gerg@uclinux.org</email>
</author>
<published>2013-08-05T01:30:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0c7e59c46e01e6f8291903c1fb8e5519fcbfe7a7'/>
<id>0c7e59c46e01e6f8291903c1fb8e5519fcbfe7a7</id>
<content type='text'>
Define 'VM_DATA_DEFAULT_FLAGS' when 'NOMMU' to pass compiling.

So move it from "include/asm/page_mm.h to "include/asm/page.h"

The related make:

  make ARCH=m68k randconfig
  make ARCH=m68k menuconfig
    choose cross compiler
    disable MMU support
  make ARCH=m68k V=1 EXTRA_CFLAGS=-W

The related error:

  security/selinux/hooks.c: In function ‘selinux_init’:
  security/selinux/hooks.c:5821:21: error: ‘VM_DATA_DEFAULT_FLAGS’ undeclared (first use in this function)

Signed-off-by: Chen Gang &lt;gang.chen@asianux.com&gt;
Signed-off-by: Greg Ungerer &lt;gerg@uclinux.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Define 'VM_DATA_DEFAULT_FLAGS' when 'NOMMU' to pass compiling.

So move it from "include/asm/page_mm.h to "include/asm/page.h"

The related make:

  make ARCH=m68k randconfig
  make ARCH=m68k menuconfig
    choose cross compiler
    disable MMU support
  make ARCH=m68k V=1 EXTRA_CFLAGS=-W

The related error:

  security/selinux/hooks.c: In function ‘selinux_init’:
  security/selinux/hooks.c:5821:21: error: ‘VM_DATA_DEFAULT_FLAGS’ undeclared (first use in this function)

Signed-off-by: Chen Gang &lt;gang.chen@asianux.com&gt;
Signed-off-by: Greg Ungerer &lt;gerg@uclinux.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>m68knommu: user generic iomap to support ioread*/iowrite*</title>
<updated>2013-08-26T06:51:13+00:00</updated>
<author>
<name>Greg Ungerer</name>
<email>gerg@uclinux.org</email>
</author>
<published>2013-08-02T07:24:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f79b8592127b6e960a30c8290a597731cba1d720'/>
<id>f79b8592127b6e960a30c8290a597731cba1d720</id>
<content type='text'>
There is no reason we cannot use the generic iomap support to give us
the ioread* and iowrite* family of IO access functions. The m68k arch with
MMU enabled does, so this makes us consistent for all m68k now.

Some potentially valid drivers will fail to compile without these,
for example:

drivers/i2c/busses/i2c-ocores.c:81:2: error: implicit declaration of
function ‘iowrite8’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:86:2: error: implicit declaration of
function ‘iowrite16’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:91:2: error: implicit declaration of
function ‘iowrite32’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:96:2: error: implicit declaration of
function ‘ioread8’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:101:2: error: implicit declaration of
function ‘ioread16’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:106:2: error: implicit declaration of
function ‘ioread32’ [-Werror=implicit-function-declaration]

Signed-off-by: Greg Ungerer &lt;gerg@uclinux.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is no reason we cannot use the generic iomap support to give us
the ioread* and iowrite* family of IO access functions. The m68k arch with
MMU enabled does, so this makes us consistent for all m68k now.

Some potentially valid drivers will fail to compile without these,
for example:

drivers/i2c/busses/i2c-ocores.c:81:2: error: implicit declaration of
function ‘iowrite8’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:86:2: error: implicit declaration of
function ‘iowrite16’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:91:2: error: implicit declaration of
function ‘iowrite32’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:96:2: error: implicit declaration of
function ‘ioread8’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:101:2: error: implicit declaration of
function ‘ioread16’ [-Werror=implicit-function-declaration]
drivers/i2c/busses/i2c-ocores.c:106:2: error: implicit declaration of
function ‘ioread32’ [-Werror=implicit-function-declaration]

Signed-off-by: Greg Ungerer &lt;gerg@uclinux.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>m68k: Ignore disabled HSYNC interrupt on Atari for irqs_disabled()</title>
<updated>2013-08-23T10:49:01+00:00</updated>
<author>
<name>Geert Uytterhoeven</name>
<email>geert@linux-m68k.org</email>
</author>
<published>2013-08-09T21:26:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3c776a07914c9a154902486ac848abc16111d35e'/>
<id>3c776a07914c9a154902486ac848abc16111d35e</id>
<content type='text'>
When running a multi-platform kernel on Atari, warning messages like
the following may be printed:

    WARNING: at /root/linux-3.10.1/init/main.c:698 do_one_initcall+0x12e/0x13a()
    initcall param_sysfs_init+0x0/0x1a4 returned with disabled interrupts

This is caused by the different definitions of ALLOWINT for Atari and
other platforms:

    #if defined(MACH_ATARI_ONLY)
    #define ALLOWINT        (~0x500)
    #else
    #define ALLOWINT        (~0x700)
    #endif

On Atari, we want to disable the high-frequency HSYNC interrupt:
  - On Atari-only kernels, this is handled completely through ALLOWINT,
  - On multi-platform kernels, this is handled by disabling the HSYNC
    interrupt from the interrupt handler.

However, as in the latter case arch_irqs_disabled_flags() didn't ignore the
disabling of the HSYNC interrupt, irqs_disabled() would detect false
positives.

Ignore the HSYNC interrupt when running on Atari to fix this.
For single-platform kernels this test is optimized away by the compiler.

Reported-by: Thorsten Glaser &lt;tg@debian.org&gt;
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Tested-by: Thorsten Glaser &lt;tg@debian.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When running a multi-platform kernel on Atari, warning messages like
the following may be printed:

    WARNING: at /root/linux-3.10.1/init/main.c:698 do_one_initcall+0x12e/0x13a()
    initcall param_sysfs_init+0x0/0x1a4 returned with disabled interrupts

This is caused by the different definitions of ALLOWINT for Atari and
other platforms:

    #if defined(MACH_ATARI_ONLY)
    #define ALLOWINT        (~0x500)
    #else
    #define ALLOWINT        (~0x700)
    #endif

On Atari, we want to disable the high-frequency HSYNC interrupt:
  - On Atari-only kernels, this is handled completely through ALLOWINT,
  - On multi-platform kernels, this is handled by disabling the HSYNC
    interrupt from the interrupt handler.

However, as in the latter case arch_irqs_disabled_flags() didn't ignore the
disabling of the HSYNC interrupt, irqs_disabled() would detect false
positives.

Ignore the HSYNC interrupt when running on Atari to fix this.
For single-platform kernels this test is optimized away by the compiler.

Reported-by: Thorsten Glaser &lt;tg@debian.org&gt;
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Tested-by: Thorsten Glaser &lt;tg@debian.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>m68k: hardirq_count() only need preempt_mask.h</title>
<updated>2013-08-14T15:14:52+00:00</updated>
<author>
<name>Frederic Weisbecker</name>
<email>fweisbec@gmail.com</email>
</author>
<published>2013-07-29T19:06:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a703f9b72407d9a4e233f4f6aea1a14ab2b74415'/>
<id>a703f9b72407d9a4e233f4f6aea1a14ab2b74415</id>
<content type='text'>
The m68k irqflags implementation needs to check hardirq
context in some cases.

As it is a very low level header file, it's better to
include preempt_mask.h rather than hardirq.h when the
only purpose is to use irq context APIs. This way we
can avoid future header circular dependencies when
vtime.h will expand to use static keys.

Signed-off-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Li Zhong &lt;zhong@linux.vnet.ibm.com&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
Cc: Kevin Hilman &lt;khilman@linaro.org&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The m68k irqflags implementation needs to check hardirq
context in some cases.

As it is a very low level header file, it's better to
include preempt_mask.h rather than hardirq.h when the
only purpose is to use irq context APIs. This way we
can avoid future header circular dependencies when
vtime.h will expand to use static keys.

Signed-off-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Li Zhong &lt;zhong@linux.vnet.ibm.com&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
Cc: Kevin Hilman &lt;khilman@linaro.org&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>m68k: Truncate base in do_div()</title>
<updated>2013-08-14T09:46:30+00:00</updated>
<author>
<name>Andreas Schwab</name>
<email>schwab@linux-m68k.org</email>
</author>
<published>2013-08-09T13:14:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ea077b1b96e073eac5c3c5590529e964767fc5f7'/>
<id>ea077b1b96e073eac5c3c5590529e964767fc5f7</id>
<content type='text'>
Explicitly truncate the second operand of do_div() to 32 bits to guard
against bogus code calling it with a 64-bit divisor.

[Thorsten]

After upgrading from 3.2 to 3.10, mounting a btrfs volume fails with:

btrfs: setting nodatacow, compression disabled
btrfs: enabling auto recovery
btrfs: disk space caching is enabled
*** ZERO DIVIDE ***   FORMAT=2
Current process id is 722
BAD KERNEL TRAP: 00000000
Modules linked in: evdev mac_hid ext4 crc16 jbd2 mbcache btrfs xor lzo_compress zlib_deflate raid6_pq crc32c libcrc32c
PC: [&lt;319535b2&gt;] __btrfs_map_block+0x11c/0x119a [btrfs]
SR: 2000  SP: 30c1fab4  a2: 30f0faf0
d0: 00000000    d1: 00001000    d2: 00000000    d3: 00000000
d4: 00010000    d5: 00000000    a0: 3085c72c    a1: 3085c72c
Process mount (pid: 722, task=30f0faf0)
Frame format=2 instr addr=319535ae
Stack from 30c1faec:
        00000000 00000020 00000000 00001000 00000000 01401000 30253928 300ffc00
        00a843ac 3026f640 00000000 00010000 0009e250 00d106c0 00011220 00000000
        00001000 301c6830 0009e32a 000000ff 00000009 3085c72c 00000000 00000000
        30c1fd14 00000000 00000020 00000000 30c1fd14 0009e26c 00000020 00000003
        00000000 0009dd8a 300b0b6c 30253928 00a843ac 00001000 00000000 00000000
        0000a008 3194e76a 30253928 00a843ac 00001000 00000000 00000000 00000002
Call Trace: [&lt;00001000&gt;] kernel_pg_dir+0x0/0x1000

    [...]

Code: 222e ff74 2a2e ff5c 2c2e ff60 4c45 1402 &lt;2d40&gt; ff64 2d41 ff68 2205 4c2e 1800 ff68 4c04 0800 2041 d1c0 2206 4c2e 1400 ff68

[Geert]

As diagnosed by Andreas, fs/btrfs/volumes.c:__btrfs_map_block()
calls

    do_div(stripe_nr, stripe_len);

with stripe_len u64, while do_div() assumes the divisor is a 32-bit number.

Due to the lack of truncation in the m68k-specific implementation of
do_div(), the division is performed using the upper 32-bit word of
stripe_len, which is zero.

This was introduced by commit 53b381b3abeb86f12787a6c40fee9b2f71edc23b
("Btrfs: RAID5 and RAID6"), which changed the divisor from
map-&gt;stripe_len (struct map_lookup.stripe_len is int) to a 64-bit temporary.

Reported-by: Thorsten Glaser &lt;tg@debian.org&gt;
Signed-off-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Tested-by: Thorsten Glaser &lt;tg@debian.org&gt;
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: stable@vger.kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Explicitly truncate the second operand of do_div() to 32 bits to guard
against bogus code calling it with a 64-bit divisor.

[Thorsten]

After upgrading from 3.2 to 3.10, mounting a btrfs volume fails with:

btrfs: setting nodatacow, compression disabled
btrfs: enabling auto recovery
btrfs: disk space caching is enabled
*** ZERO DIVIDE ***   FORMAT=2
Current process id is 722
BAD KERNEL TRAP: 00000000
Modules linked in: evdev mac_hid ext4 crc16 jbd2 mbcache btrfs xor lzo_compress zlib_deflate raid6_pq crc32c libcrc32c
PC: [&lt;319535b2&gt;] __btrfs_map_block+0x11c/0x119a [btrfs]
SR: 2000  SP: 30c1fab4  a2: 30f0faf0
d0: 00000000    d1: 00001000    d2: 00000000    d3: 00000000
d4: 00010000    d5: 00000000    a0: 3085c72c    a1: 3085c72c
Process mount (pid: 722, task=30f0faf0)
Frame format=2 instr addr=319535ae
Stack from 30c1faec:
        00000000 00000020 00000000 00001000 00000000 01401000 30253928 300ffc00
        00a843ac 3026f640 00000000 00010000 0009e250 00d106c0 00011220 00000000
        00001000 301c6830 0009e32a 000000ff 00000009 3085c72c 00000000 00000000
        30c1fd14 00000000 00000020 00000000 30c1fd14 0009e26c 00000020 00000003
        00000000 0009dd8a 300b0b6c 30253928 00a843ac 00001000 00000000 00000000
        0000a008 3194e76a 30253928 00a843ac 00001000 00000000 00000000 00000002
Call Trace: [&lt;00001000&gt;] kernel_pg_dir+0x0/0x1000

    [...]

Code: 222e ff74 2a2e ff5c 2c2e ff60 4c45 1402 &lt;2d40&gt; ff64 2d41 ff68 2205 4c2e 1800 ff68 4c04 0800 2041 d1c0 2206 4c2e 1400 ff68

[Geert]

As diagnosed by Andreas, fs/btrfs/volumes.c:__btrfs_map_block()
calls

    do_div(stripe_nr, stripe_len);

with stripe_len u64, while do_div() assumes the divisor is a 32-bit number.

Due to the lack of truncation in the m68k-specific implementation of
do_div(), the division is performed using the upper 32-bit word of
stripe_len, which is zero.

This was introduced by commit 53b381b3abeb86f12787a6c40fee9b2f71edc23b
("Btrfs: RAID5 and RAID6"), which changed the divisor from
map-&gt;stripe_len (struct map_lookup.stripe_len is int) to a 64-bit temporary.

Reported-by: Thorsten Glaser &lt;tg@debian.org&gt;
Signed-off-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Tested-by: Thorsten Glaser &lt;tg@debian.org&gt;
Signed-off-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: stable@vger.kernel.org
</pre>
</div>
</content>
</entry>
</feed>
