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571367 Commits (a4cc3c3c7356ded3eba5905f94279382a05d9c96)

Author SHA1 Message Date
Rasmus Villemoes 251c723455 lib/test_printf.c: test dentry printing
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:29 -08:00
Rasmus Villemoes 857cca4d56 lib/test_printf.c: add test for large bitmaps
Following "lib/vsprintf.c: expand field_width to 24 bits", let's add a
test to see that we now actually support bitmaps with 65536 bits.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:29 -08:00
Rasmus Villemoes b79a7db37d lib/test_printf.c: account for kvasprintf tests
These should also count as performed tests.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:29 -08:00
Rasmus Villemoes 1ca8e8ebe9 lib/test_printf.c: add a few number() tests
This adds a few tests to test_number, one of which serves to document
another deviation from POSIX/C99 (printing 0 with an explicit precision
of 0).

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:28 -08:00
Rasmus Villemoes f176eb4ce9 lib/test_printf.c: test precision quirks
The kernel's printf doesn't follow the standards in a few corner cases
(which are probably mostly irrelevant).  Add tests that document the
current behaviour.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:28 -08:00
Rasmus Villemoes 331e4deb6d lib/test_printf.c: check for out-of-bound writes
Add a few padding bytes on either side of the test buffer, and check
that these (and the part of the buffer not used) are untouched by
vsnprintf.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:28 -08:00
Rasmus Villemoes fd0515d50f lib/test_printf.c: don't BUG
BUG is a completely unnecessarily big hammer, and we're more likely to
get the internal bug reported if we just pr_err() and ensure the test
suite fails.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:27 -08:00
Rasmus Villemoes 8e2a2bfdb8 lib/kasprintf.c: add sanity check to kvasprintf
kasprintf relies on being able to replay the formatting and getting the
same result (in particular, the same length).  This will almost always
work, but it is possible that the object pointed to by a %s or %p
argument changed under us (so we might get truncated output).  Add a
somewhat paranoid sanity check and let's see if it ever triggers.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:27 -08:00
Rasmus Villemoes 4d72ba014b lib/vsprintf.c: warn about too large precisions and field widths
The field width is overloaded to pass some extra information for some %p
extensions (e.g.  #bits for %pb).  But we might silently truncate the
passed value when we stash it in struct printf_spec (see e.g.
"lib/vsprintf.c: expand field_width to 24 bits").  Hopefully 23 value
bits should now be enough for everybody, but if not, let's make some
noise.

Do the same for the precision.  In both cases, clamping seems more
sensible than truncating.  While, according to POSIX, "A negative
precision is taken as if the precision were omitted.", the kernel's
printf has always treated that case as if the precision was 0, so we use
that as lower bound.  For the field width, the smallest representable
value is actually -(1<<23), but a negative field width means 'set the
LEFT flag and use the absolute value', so we want the absolute value to
fit.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:27 -08:00
Rasmus Villemoes 1c7a8e622e lib/vsprintf.c: help gcc make number() smaller
One consequence of the reorganization of struct printf_spec to make
field_width 24 bits was that number() gained about 180 bytes.  Since
spec is never passed to other functions, we can help gcc make number()
lose most of that extra weight by using local variables for the field
width and precision.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes d048419311 lib/vsprintf.c: expand field_width to 24 bits
Maurizio Lombardi reported a problem [1] with the %pb extension: It
doesn't work for sufficiently large bitmaps, since the size is stashed
in the field_width field of the struct printf_spec, which is currently
an s16.  Concretely, this manifested itself in
/sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap
printer got a size of 0, which is the 16 bit truncation of the actual
bitmap size.

We do want to keep struct printf_spec at 8 bytes so that it can cheaply
be passed by value.  The qualifier field is only used for internal
bookkeeping in format_decode, so we might as well use a local variable
for that.  This gives us an additional 8 bits, which we can then use for
the field width.

To stay in 8 bytes, we need to do a little rearranging and make the type
member a bitfield as well.  For consistency, change all the members to
bit fields.  gcc doesn't generate much worse code with these changes (in
fact, bloat-o-meter says we save 300 bytes - which I think is a little
surprising).

I didn't find a BUILD_BUG/compiletime_assertion/... which would work
outside function context, so for now I just open-coded it.

[1] http://thread.gmane.org/gmane.linux.kernel/2034835

[akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reported-by: Maurizio Lombardi <mlombard@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes 34fc8b9076 lib/vsprintf.c: eliminate potential race in string()
If the string corresponding to a %s specifier can change under us, we
might end up copying a \0 byte to the output buffer.  There might be
callers who expect the output buffer to contain a genuine C string whose
length is exactly the snprintf return value (assuming truncation hasn't
happened or has been checked for).

We can avoid this by only passing over the source string once, stopping
the first time we meet a nul byte (or when we reach the given
precision), and then letting widen_string() handle left/right space
padding.  As a small bonus, this code reuse also makes the generated
code slightly smaller.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes 95508cfa10 lib/vsprintf.c: move string() below widen_string()
This is pure code movement, making sure the widen_string() helper is
defined before the string() function.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes cfccde04e2 lib/vsprintf.c: pull out padding code from dentry_name()
Pull out the logic in dentry_name() which handles field width space
padding, in preparation for reusing it from string().  Rename the
widen() helper to move_right(), since it is used for handling the
!(flags & LEFT) case.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:25 -08:00
Tejun Heo 8d91f8b153 printk: do cond_resched() between lines while outputting to consoles
@console_may_schedule tracks whether console_sem was acquired through
lock or trylock.  If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched().  This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.

However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines.  Also, only a few drivers call
console_conditional_schedule() to begin with.  This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.

If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.

Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Calvin Owens <calvinowens@fb.com>
Acked-by: Jan Kara <jack@suse.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:25 -08:00
Thierry Reding 81cc26f2bd printk: only unregister boot consoles when necessary
Boot consoles are typically replaced by proper consoles during the boot
process.  This can be problematic if the boot console data is part of
the init section that is reclaimed late during boot.  If the proper
console does not register before this point in time, the boot console
will need to be removed (so that the freed memory is not accessed),
leaving the system without output for some time.

There are various reasons why the proper console may not register early
enough, such as deferred probe or the driver being a loadable module.
If that happens, there is some amount of time where no console messages
are visible to the user, which in turn can mean that they won't see
crashes or other potentially useful information.

To avoid this situation, only remove the boot console when it resides in
the init section.  Code exists to replace the boot console by the proper
console when it is registered, keeping a seamless transition between the
boot and proper consoles.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:25 -08:00
Thierry Reding 9795593625 asm/sections: add helpers to check for section data
Add a helper to check if an object (given an address and a size) is part
of a section (given beginning and end addresses).  For convenience, also
provide a helper that performs this check for __init data using the
__init_begin and __init_end limits.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:24 -08:00
Andrew Morton b493c34309 kernel/stop_machine.c: remove CONFIG_SMP dependencies
stop_machine.o is only built if CONFIG_SMP=y, so this ifdef always
evaluates to true.

[akpm@linux-foundation.org: remove now-unneeded ifdef]
Reported-by: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:24 -08:00
Riku Voipio b2113a417c uselib: default depending if libc5 was used
uselib hasn't been used since libc5; glibc does not use it.  Deprecate
uselib a bit more, by making the default y only if libc5 was widely used
on the plaform.

This makes arm64 kernel built with defconfig slightly smaller

bloat-o-meter:
  add/remove: 0/3 grow/shrink: 0/2 up/down: 0/-1390 (-1390)
  function                                     old     new   delta
  kernel_config_data                         18164   18162      -2
  uselib_flags                                  20       -     -20
  padzero                                      216     192     -24
  sys_uselib                                   380       -    -380
  load_elf_library                             964       -    -964

Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:24 -08:00
Viresh Kumar dfffa587a6 err.h: add (missing) unlikely() to IS_ERR_OR_NULL()
IS_ERR_VALUE() already contains it and so we need to add this only to
the !ptr check.  That will allow users of IS_ERR_OR_NULL(), to not add
this compiler flag.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:24 -08:00
Will Deacon da48d094ce Kconfig: remove HAVE_LATENCYTOP_SUPPORT
As illustrated by commit a3afe70b83 ("[S390] latencytop s390
support."), HAVE_LATENCYTOP_SUPPORT is defined by an architecture to
advertise an implementation of save_stack_trace_tsk.

However, as of 9212ddb5ea ("stacktrace: provide save_stack_trace_tsk()
weak alias") a dummy implementation is provided if STACKTRACE=y.  Given
that LATENCYTOP already depends on STACKTRACE_SUPPORT and selects
STACKTRACE, we can remove HAVE_LATENCYTOP_SUPPORT altogether.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Helge Deller <deller@gmx.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:23 -08:00
Yaowei Bai 3f1bfd9413 include/linux/kdev_t.h: remove new_valid_dev()
As all new_valid_dev() checks have been removed it's time to drop
new_valid_dev() itself.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:23 -08:00
Yaowei Bai 4c416f42ee fs/stat.c: drop the last new_valid_dev check
New_valid_dev() always returns true, so that's unnecessary to perform
new_valid_dev() checks in some filesystems.  Most checks of
new_valid_dev() have been removed so let's drop this last one and then
we can remove new_valid_dev() from the source code.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:23 -08:00
Michal Nazarewicz 8f57e4d930 include/linux/kernel.h: change abs() macro so it uses consistent return type
Rewrite abs() so that its return type does not depend on the
architecture and no unexpected type conversion happen inside of it.  The
only conversion is from unsigned to signed type.  char is left as a
return type but treated as a signed type regradless of it's actual
signedness.

With the old version, int arguments were promoted to long and depending
on architecture a long argument might result in s64 or long return type
(which may or may not be the same).

This came after some back and forth with Nicolas.  The current macro has
different return type (for the same input type) depending on
architecture which might be midly iritating.

An alternative version would promote to int like so:

	#define abs(x)	__abs_choose_expr(x, long long,			\
			__abs_choose_expr(x, long,			\
			__builtin_choose_expr(				\
				sizeof(x) <= sizeof(int),		\
				({ int __x = (x); __x<0?-__x:__x; }),	\
				((void)0))))

I have no preference but imagine Linus might.  :] Nicolas argument against
is that promoting to int causes iconsistent behaviour:

	int main(void) {
		unsigned short a = 0, b = 1, c = a - b;
		unsigned short d = abs(a - b);
		unsigned short e = abs(c);
		printf("%u %u\n", d, e);  // prints: 1 65535
	}

Then again, no sane person expects consistent behaviour from C integer
arithmetic.  ;)

Note:

  __builtin_types_compatible_p(unsigned char, char) is always false, and
  __builtin_types_compatible_p(signed char, char) is also always false.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:22 -08:00
Vasily Kulikov b8a0255db9 include/linux/poison.h: use POISON_POINTER_DELTA for poison pointers
TIMER_ENTRY_STATIC and TAIL_MAPPING are defined as poison pointers which
should point to nowhere.  Redefine them using POISON_POINTER_DELTA
arithmetics to make sure they really point to non-mappable area declared
by the target architecture.

Signed-off-by: Vasily Kulikov <segoon@openwall.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Solar Designer <solar@openwall.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:22 -08:00
Helge Deller b0e551313e parisc: Protect huge page pte changes with spinlocks
PA-RISC doesn't have atomic instructions to modify page table entries, so it
takes spinlock in the TLB handler and modifies the page table entry
non-atomically. If you modify the page table entry without the spinlock, you
may race with TLB handler on another CPU and your modification may be lost.
Protect against that with usage of purge_tlb_start() and purge_tlb_end() which
handles the TLB spinlock.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v4.4
2016-01-16 19:19:14 +01:00
Sven Eckelmann 42eff6a617 batman-adv: Drop immediate orig_node free function
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.

But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_orig_node_free_ref.

Fixes: 72822225bd ("batman-adv: Fix rcu_barrier() miss due to double call_rcu() in TT code")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:50:00 +08:00
Sven Eckelmann b4d922cfc9 batman-adv: Drop immediate batadv_hard_iface free function
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.

But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_hardif_free_ref.

Fixes: 89652331c0 ("batman-adv: split tq information in neigh_node struct")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:49:51 +08:00
Sven Eckelmann ae3e1e36e3 batman-adv: Drop immediate neigh_ifinfo free function
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.

But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_neigh_ifinfo_free_ref.

Fixes: 89652331c0 ("batman-adv: split tq information in neigh_node struct")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:49:38 +08:00
Sven Eckelmann f638969287 batman-adv: Drop immediate batadv_hardif_neigh_node free function
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.

But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_hardif_neigh_free_ref.

Fixes: cef63419f7 ("batman-adv: add list of unique single hop neighbors per hard-interface")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:49:28 +08:00
Sven Eckelmann 2baa753c27 batman-adv: Drop immediate batadv_neigh_node free function
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.

But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_neigh_node_free_ref.

Fixes: 89652331c0 ("batman-adv: split tq information in neigh_node struct")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:49:16 +08:00
Sven Eckelmann deed96605f batman-adv: Drop immediate batadv_orig_ifinfo free function
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.

But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_orig_ifinfo_free_ref.

Fixes: 7351a4822d ("batman-adv: split out router from orig_node")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:49:05 +08:00
Sven Eckelmann 44e8e7e91d batman-adv: Avoid recursive call_rcu for batadv_nc_node
The batadv_nc_node_free_ref function uses call_rcu to delay the free of the
batadv_nc_node object until no (already started) rcu_read_lock is enabled
anymore. This makes sure that no context is still trying to access the
object which should be removed. But batadv_nc_node also contains a
reference to orig_node which must be removed.

The reference drop of orig_node was done in the call_rcu function
batadv_nc_node_free_rcu but should actually be done in the
batadv_nc_node_release function to avoid nested call_rcus. This is
important because rcu_barrier (e.g. batadv_softif_free or batadv_exit) will
not detect the inner call_rcu as relevant for its execution. Otherwise this
barrier will most likely be inserted in the queue before the callback of
the first call_rcu was executed. The caller of rcu_barrier will therefore
continue to run before the inner call_rcu callback finished.

Fixes: d56b1705e2 ("batman-adv: network coding - detect coding nodes and remove these after timeout")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:48:41 +08:00
Sven Eckelmann 63b3992722 batman-adv: Avoid recursive call_rcu for batadv_bla_claim
The batadv_claim_free_ref function uses call_rcu to delay the free of the
batadv_bla_claim object until no (already started) rcu_read_lock is enabled
anymore. This makes sure that no context is still trying to access the
object which should be removed. But batadv_bla_claim also contains a
reference to backbone_gw which must be removed.

The reference drop of backbone_gw was done in the call_rcu function
batadv_claim_free_rcu but should actually be done in the
batadv_claim_release function to avoid nested call_rcus. This is important
because rcu_barrier (e.g. batadv_softif_free or batadv_exit) will not
detect the inner call_rcu as relevant for its execution. Otherwise this
barrier will most likely be inserted in the queue before the callback of
the first call_rcu was executed. The caller of rcu_barrier will therefore
continue to run before the inner call_rcu callback finished.

Fixes: 23721387c4 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-01-16 22:48:29 +08:00
Ivan Vecera 6c3f5aef11 bna: fix Rx data corruption with VLAN stripping enabled and MTU > 4096
The multi-buffer Rx mode implemented in the past introduced
a regression that causes a data corruption for received VLAN
traffic when VLAN tag stripping is enabled. This mode is supported
only be newer chipsets (1860) and is enabled when MTU > 4096.

When this mode is enabled Rx queue contains buffers with fixed size
2048 bytes. Any incoming packet larger than 2048 is divided into
multiple buffers that are attached as skb frags in polling routine.

The driver assumes that all buffers associated with a packet except
the last one is fully used (e.g. packet with size 5000 are divided
into 3 buffers 2048 + 2048 + 904 bytes) and ignores true size reported
in completions. This assumption is usually true but not when VLAN
packet is received and VLAN tag stripping is enabled. In this case
the first buffer is 2044 bytes long but as the driver always assumes
2048 bytes then 4 extra random bytes are included between the first
and the second frag. Additionally the driver sets checksum as correct
so the packet is properly processed by the core.

The driver needs to check the size of used space in each Rx buffer
reported by FW and not blindly use the fixed value.

Cc: Rasesh Mody <rasesh.mody@qlogic.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Reviewed-by: Rasesh Mody <rasesh.mody@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-15 21:49:25 -05:00
Linus Torvalds ece6267878 The clk framework and driver changes for 4.5 look pretty typical. The
bulk of the changes are to clk controller drivers, though some
 improvements to the core and some re-usable blocks/templates also
 received some love. In this past cycle the clk maintainers developed a
 good workflow for handling the common case of patch submissions
 containing a new drivers, new shared Device Tree header and a new Device
 Tree binding description. This requires coordination with the Device
 Tree maintainers and with the architecture maintainers (typically the
 arm-soc tree in our case). This explains the increase in changes to
 include/dt-bindings/... and to
 Documentation/devicetree/bindings/clock/... coming from the clk tree.
 The same commits can be expected to come through those trees on
 occasion, through the use of shared, immutable branches.
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Merge tag 'clk-for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux

Pull clk framework updates from Michael Turquette:
 "The clk framework and driver changes for 4.5 look pretty typical.  The
  bulk of the changes are to clk controller drivers, though some
  improvements to the core and some re-usable blocks/templates also
  received some love.

  In this past cycle the clk maintainers developed a good workflow for
  handling the common case of patch submissions containing a new
  drivers, new shared Device Tree header and a new Device Tree binding
  description.  This requires coordination with the Device Tree
  maintainers and with the architecture maintainers (typically the
  arm-soc tree in our case).

  This explains the increase in changes to include/dt-bindings/... and
  to Documentation/devicetree/bindings/clock/... coming from the clk
  tree.  The same commits can be expected to come through those trees on
  occasion, through the use of shared, immutable branches"

* tag 'clk-for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (125 commits)
  clk: remove duplicated COMMON_CLK_NXP record from clk/Kconfig
  clk: fix clk-gpio.c with optional clock= DT property
  clk: rockchip: fix section mismatches with new child-clocks
  clk: gpio: handle error codes for of_clk_get_parent_count()
  clk: gpio: fix memory leak
  clk: shmobile: r8a7795: Add SATA0 clock
  clk: bcm2835: Add PWM clock support
  clk: bcm2835: Support for clock parent selection
  clk: bcm2835: add a round up ability to the clock divisor
  clk: lpc32xx: add common clock framework driver
  clk: lpc18xx: add NXP specific COMMON_CLK_NXP configuration symbol
  dt-bindings: clock: add NXP LPC32xx clock list for consumers
  dt-bindings: clock: add description of LPC32xx USB clock controller
  dt-bindings: clock: add description of LPC32xx clock controller
  clk: rockchip: rk3036: include downstream muxes into fractional dividers
  clk: add flag for clocks that need to be enabled on rate changes
  clk: rockchip: Allow the RK3288 SPDIF clocks to change their parent
  clk: rockchip: include downstream muxes into fractional dividers
  clk: rockchip: handle mux dependency of fractional dividers
  clk: bcm2835: Add a driver for the auxiliary peripheral clock gates.
  ...
2016-01-15 18:21:28 -08:00
Linus Torvalds d45187aaf0 Merge branch 'dmi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
Pull dmi updates from Jean Delvare.

* 'dmi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  firmware: dmi_scan: Save SMBIOS Type 9 System Slots
  firmware: dmi_scan: Fix dmi_find_device description
  firmware: dmi_scan: Clarify dmi_save_extended_devices
  firmware: dmi_scan: Optimize dmi_save_extended_devices
2016-01-15 18:12:18 -08:00
Martijn Coenen 6611d8d761 memcg: only free spare array when readers are done
A spare array holding mem cgroup threshold events is kept around to make
sure we can always safely deregister an event and have an array to store
the new set of events in.

In the scenario where we're going from 1 to 0 registered events, the
pointer to the primary array containing 1 event is copied to the spare
slot, and then the spare slot is freed because no events are left.
However, it is freed before calling synchronize_rcu(), which means
readers may still be accessing threshold->primary after it is freed.

Fixed by only freeing after synchronize_rcu().

Signed-off-by: Martijn Coenen <maco@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Naoya Horiguchi 98fd1ef424 mm: soft-offline: exit with failure for non anonymous thp
Currently memory_failure() doesn't handle non anonymous thp case,
because we can hardly expect the error handling to be successful, and it
can just hit some corner case which results in BUG_ON or something
severe like that.  This is also the case for soft offline code, so let's
make it in the same way.

Orignal code has a MF_COUNT_INCREASED check before put_hwpoison_page(),
but it's unnecessary because get_any_page() is already called when
running on this code, which takes a refcount of the target page
regardress of the flag.  So this patch also removes it.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Naoya Horiguchi acc14dc4bd mm: soft-offline: clean up soft_offline_page()
soft_offline_page() has some deeply indented code, that's the sign of
demand for cleanup.  So let's do this.  No functionality change.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Mike Kravetz 4aae8d1c05 mm/hugetlbfs: unmap pages if page fault raced with hole punch
Page faults can race with fallocate hole punch.  If a page fault happens
between the unmap and remove operations, the page is not removed and
remains within the hole.  This is not the desired behavior.  The race is
difficult to detect in user level code as even in the non-race case, a
page within the hole could be faulted back in before fallocate returns.
If userfaultfd is expanded to support hugetlbfs in the future, this race
will be easier to observe.

If this race is detected and a page is mapped, the remove operation
(remove_inode_hugepages) will unmap the page before removing.  The unmap
within remove_inode_hugepages occurs with the hugetlb_fault_mutex held
so that no other faults will be processed until the page is removed.

The (unmodified) routine hugetlb_vmdelete_list was moved ahead of
remove_inode_hugepages to satisfy the new reference.

[akpm@linux-foundation.org: move hugetlb_vmdelete_list()]
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Mike Kravetz 9aacdd354d fs/hugetlbfs/inode.c: fix bugs in hugetlb_vmtruncate_list()
Hillf Danton noticed bugs in the hugetlb_vmtruncate_list routine.  The
argument end is of type pgoff_t.  It was being converted to a vaddr
offset and passed to unmap_hugepage_range.  However, end was also being
used as an argument to the vma_interval_tree_foreach controlling loop.
In addition, the conversion of end to vaddr offset was incorrect.

hugetlb_vmtruncate_list is called as part of a file truncate or
fallocate hole punch operation.

When truncating a hugetlbfs file, this bug could prevent some pages from
being unmapped.  This is possible if there are multiple vmas mapping the
file, and there is a sufficiently sized hole between the mappings.  The
size of the hole between two vmas (A,B) must be such that the starting
virtual address of B is greater than (ending virtual address of A <<
PAGE_SHIFT).  In this case, the pages in B would not be unmapped.  If
pages are not properly unmapped during truncate, the following BUG is
hit:

	kernel BUG at fs/hugetlbfs/inode.c:428!

In the fallocate hole punch case, this bug could prevent pages from
being unmapped as in the truncate case.  However, for hole punch the
result is that unmapped pages will not be removed during the operation.
For hole punch, it is also possible that more pages than desired will be
unmapped.  This unnecessary unmapping will cause page faults to
reestablish the mappings on subsequent page access.

Fixes: 1bfad99ab (" hugetlbfs: hugetlb_vmtruncate_list() needs to take a range")Reported-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org>	[4.3]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Hugh Dickins 9f8bdb3f3d mm: make swapoff more robust against soft dirty
Both s390 and powerpc have hit the issue of swapoff hanging, when
CONFIG_HAVE_ARCH_SOFT_DIRTY and CONFIG_MEM_SOFT_DIRTY ifdefs were not
quite as x86_64 had them.  I think it would be much clearer if
HAVE_ARCH_SOFT_DIRTY was just a Kconfig option set by architectures to
determine whether the MEM_SOFT_DIRTY option should be offered, and the
actual code depend upon CONFIG_MEM_SOFT_DIRTY alone.

But won't embark on that change myself: instead make swapoff more
robust, by using pte_swp_clear_soft_dirty() on each pte it encounters,
without an explicit #ifdef CONFIG_MEM_SOFT_DIRTY.  That being a no-op,
whether the bit in question is defined as 0 or the asm-generic fallback
is used, unless soft dirty is fully turned on.

Why "maybe" in maybe_same_pte()? Rename it pte_same_as_swp().

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Kirill A. Shutemov 88f306b68c mm: fix locking order in mm_take_all_locks()
Dmitry Vyukov has reported[1] possible deadlock (triggered by his
syzkaller fuzzer):

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&hugetlbfs_i_mmap_rwsem_key);
                               lock(&mapping->i_mmap_rwsem);
                               lock(&hugetlbfs_i_mmap_rwsem_key);
  lock(&mapping->i_mmap_rwsem);

Both traces points to mm_take_all_locks() as a source of the problem.
It doesn't take care about ordering or hugetlbfs_i_mmap_rwsem_key (aka
mapping->i_mmap_rwsem for hugetlb mapping) vs.  i_mmap_rwsem.

huge_pmd_share() does memory allocation under hugetlbfs_i_mmap_rwsem_key
and allocator can take i_mmap_rwsem if it hit reclaim.  So we need to
take i_mmap_rwsem from all hugetlb VMAs before taking i_mmap_rwsem from
rest of VMAs.

The patch also documents locking order for hugetlbfs_i_mmap_rwsem_key.

[1] http://lkml.kernel.org/r/CACT4Y+Zu95tBs-0EvdiAKzUOsb4tczRRfCRTpLr4bg_OP9HuVg@mail.gmail.com

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Liang Chen d645fc0eab mm: mempolicy: skip non-migratable VMAs when setting MPOL_MF_LAZY
MPOL_MF_LAZY is not visible from userspace since a720094ded ("mm:
mempolicy: Hide MPOL_NOOP and MPOL_MF_LAZY from userspace for now"), but
it should still skip non-migratable VMAs such as VM_IO, VM_PFNMAP, and
VM_HUGETLB VMAs, and avoid useless overhead of minor faults.

Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Signed-off-by: Gavin Guo <gavin.guo@canonical.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Alexander Kuleshov f16f091b59 mm/page_alloc.c: remove unused struct zone *z variable
Remove unused struct zone *z variable which appeared in 86051ca5ea
("mm: fix usemap initialization").

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Wang Xiaoqiang 7f43add451 mm/mlock.c: change can_do_mlock return value type to boolean
Since can_do_mlock only return 1 or 0, so make it boolean.

No functional change.

[akpm@linux-foundation.org: update declaration in mm.h]
Signed-off-by: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Wang Xiaoqiang 61e165578d mm/vmalloc.c: use macro IS_ALIGNED to judge the aligment
Just cleanup, no functional change.

Signed-off-by: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Tejun Heo 654a0dd095 cgroup, memcg, writeback: drop spurious rcu locking around mem_cgroup_css_from_page()
In earlier versions, mem_cgroup_css_from_page() could return non-root
css on a legacy hierarchy which can go away and required rcu locking;
however, the eventual version simply returns the root cgroup if memcg is
on a legacy hierarchy and thus doesn't need rcu locking around or in it.
Remove spurious rcu lockings.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Wang Xiaoqiang 6f8d2b8a26 mm/page_isolation: do some cleanup in "undo_isolate_page_range"
Use "IS_ALIGNED" to judge the alignment, rather than directly judging.

Signed-off-by: Wang Xiaoqiang <wang_xiaoq@126.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00