linux-stable.git/arch/frv, branch v3.2.69

vm: add VM_FAULT_SIGSEGV handling support

2015-02-20T00:49:40+00:00

commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai 
Tested-by: Jan Engelhardt 
Acked-by: Heiko Carstens  # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds 
[bwh: Backported to 3.2:
 - Adjust filenames, context
 - Drop arc, metag, nios2 and lustre changes
 - For sh, patch both 32-bit and 64-bit implementations to use goto bad_area
 - For s390, pass int_code and trans_exc_code as arguments to do_no_context()
   and do_sigsegv()]
Signed-off-by: Ben Hutchings

kgdb: follow rename pack_hex_byte() to hex_byte_pack()

2011-11-01T00:30:56+00:00

There is no functional change.

Signed-off-by: Andy Shevchenko 
Acked-by: Jesper Nilsson 
Cc: David Howells 
Cc: Koichi Yasutake 
Cc: Jason Wessel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

All Arch: remove linkage for sys_nfsservctl system call

2011-08-26T22:09:58+00:00

The nfsservctl system call is now gone, so we should remove all
linkage for it.

Signed-off-by: NeilBrown 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Linus Torvalds

Merge branch 'apei' into apei-release

2011-08-03T15:30:42+00:00

Some trivial conflicts due to other various merges
adding to the end of common lists sooner than this one.

	arch/ia64/Kconfig
	arch/powerpc/Kconfig
	arch/x86/Kconfig
	lib/Kconfig
	lib/Makefile

Signed-off-by: Len Brown

Add Kconfig option ARCH_HAVE_NMI_SAFE_CMPXCHG

2011-08-03T15:12:37+00:00

cmpxchg() is widely used by lockless code, including NMI-safe lockless
code.  But on some architectures, the cmpxchg() implementation is not
NMI-safe, on these architectures the lockless code may need a
spin_trylock_irqsave() based implementation.

This patch adds a Kconfig option: ARCH_HAVE_NMI_SAFE_CMPXCHG, so that
NMI-safe lockless code can depend on it or provide different
implementation according to it.

On many architectures, cmpxchg is only NMI-safe for several specific
operand sizes. So, ARCH_HAVE_NMI_SAFE_CMPXCHG define in this patch
only guarantees cmpxchg is NMI-safe for sizeof(unsigned long).

Signed-off-by: Huang Ying 
Acked-by: Mike Frysinger 
Acked-by: Paul Mundt 
Acked-by: Hans-Christian Egtvedt 
Acked-by: Benjamin Herrenschmidt 
Acked-by: Chris Metcalf 
Acked-by: Richard Henderson 
CC: Mikael Starvik 
Acked-by: David Howells 
CC: Yoshinori Sato 
CC: Tony Luck 
CC: Hirokazu Takata 
CC: Geert Uytterhoeven 
CC: Michal Simek 
Acked-by: Ralf Baechle 
CC: Kyle McMartin 
CC: Martin Schwidefsky 
CC: Chen Liqin 
CC: "David S. Miller" 
CC: Ingo Molnar 
CC: Chris Zankel 
Signed-off-by: Len Brown

frv: remove unnecessary code

2011-07-30T06:41:09+00:00

remove unnecessary code that matches this coccinelle pattern

	if (...)
		return ret;
	return ret;

Signed-off-by: Greg Dietsche 
Signed-off-by: David Howells 
Signed-off-by: Linus Torvalds

atomic: cleanup asm-generic atomic*.h inclusion

2011-07-26T23:49:47+00:00

After changing all consumers of atomics to include , we
ran into some compile time errors due to this dependency chain:

linux/atomic.h
  -> asm/atomic.h
    -> asm-generic/atomic-long.h

where atomic-long.h could use funcs defined later in linux/atomic.h
without a prototype.  This patches moves the code that includes
asm-generic/atomic*.h to linux/atomic.h.

Archs that need  need to select
CONFIG_GENERIC_ATOMIC64 from now on (some of them used to include it
unconditionally).

Compile tested on i386 and x86_64 with allnoconfig.

Signed-off-by: Arun Sharma 
Cc: Eric Dumazet 
Cc: Ingo Molnar 
Cc: David Miller 
Acked-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

atomic: move atomic_add_unless to generic code

2011-07-26T23:49:47+00:00

This is in preparation for more generic atomic primitives based on
__atomic_add_unless.

Signed-off-by: Arun Sharma 
Signed-off-by: Hans-Christian Egtvedt 
Reviewed-by: Eric Dumazet 
Cc: Ingo Molnar 
Cc: David Miller 
Acked-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

atomic: use

2011-07-26T23:49:47+00:00

This allows us to move duplicated code in 
(atomic_inc_not_zero() for now) to 

Signed-off-by: Arun Sharma 
Reviewed-by: Eric Dumazet 
Cc: Ingo Molnar 
Cc: David Miller 
Cc: Eric Dumazet 
Acked-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

asm-generic: add another generic ext2 atomic bitops

2011-07-26T23:49:46+00:00

The majority of architectures implement ext2 atomic bitops as
test_and_{set,clear}_bit() without spinlock.

This adds this type of generic implementation in ext2-atomic-setbit.h and
use it wherever possible.

Signed-off-by: Akinobu Mita 
Suggested-by: Andreas Dilger 
Suggested-by: Arnd Bergmann 
Acked-by: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds