Commit Graph

23 Commits

Author SHA1 Message Date
Russell King
3ad55155b2 Merge branch 'devel-stable' into for-next
Conflicts:
	arch/arm/kernel/entry-armv.S
2011-07-22 23:09:07 +01:00
Jon Medhurst
594810621d ARM: Thumb-2: Fix exception return sequence to restore stack correctly
The implementation of svc_exit didn't take into account any stack hole
created by svc_entry; as happens with the undef handler when kprobes are
configured. The fix is to read the saved value of SP rather than trying
to calculate it.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:40 +00:00
Russell King
02fe2845d6 ARM: entry: avoid enabling interrupts in prefetch/data abort handlers
Avoid enabling interrupts if the parent context had interrupts enabled
in the abort handler assembly code, and move this into the breakpoint/
page/alignment fault handlers instead.

This gets rid of some special-casing for the breakpoint fault handlers
from the low level abort handler path.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-02 10:56:00 +01:00
Russell King
7db44c75a2 ARM: v6k: select clear exclusive code seqences according to V6 variants
If CONFIG_CPU_V6 is enabled, then the kernel must support ARMv6 CPUs
which don't have the V6K extensions implemented.  Always use the
dummy store-exclusive method to ensure that the exclusive monitors are
cleared.

If CONFIG_CPU_V6 is not set, but CONFIG_CPU_32v6K is enabled, then we
have the K extensions available on all CPUs we're building support for,
so we can use the new clear-exclusive instruction.

Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-02 21:23:28 +00:00
Will Deacon
7e20269647 ARM: hw_breakpoint: disable preemption during debug exception handling
On ARM, debug exceptions occur in the form of data or prefetch aborts.
One difference is that debug exceptions require access to per-cpu banked
registers and data structures which are not saved in the low-level exception
code. For kernels built with CONFIG_PREEMPT, there is an unlikely scenario
that the debug handler ends up running on a different CPU from the one
that originally signalled the event, resulting in random data being read
from the wrong registers.

This patch adds a debug_entry macro to the low-level exception handling
code which checks whether the taken exception is a debug exception. If
it is, the preempt count for the faulting process is incremented. After
the debug handler has finished, the count is decremented.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2010-12-06 11:55:56 +00:00
Anders Grafström
8e4971f2fb ARM: 5991/1: Fix regression in restore_user_regs macro
ARMv5T and earlier require that a ldm {}^ instruction is not followed
by an instruction that accesses banked registers. This patch restores
the nop that was lost in commit b86040a59f.

Signed-off-by: Anders Grafström <grfstrm@users.sourceforge.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-03-15 17:20:08 +00:00
Catalin Marinas
a771fe6e4e ARM: 5757/1: Thumb-2: Correct "mov.w pc, lr" instruction which is unpredictable
The 32-bit wide variant of "mov pc, reg" in Thumb-2 is unpredictable
causing improper handling of the undefined instructions not caught by
the kernel. This patch adds a movw_pc macro for such situations
(currently only used in call_fpe).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-10-14 10:33:05 +01:00
Nicolas Pitre
9e6ec39bec make Linux bootable on ARM again
Commit 200b812d00 "Clear the exclusive monitor when returning from an
exception" broke the vast majority of ARM systems in the wild which are
still pre ARMv6.  The kernel is crashing on the first occurrence of an
exception due to the removal of the actual return instruction for them.
Let's add it back.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-26 10:06:53 -07:00
Catalin Marinas
200b812d00 Clear the exclusive monitor when returning from an exception
The patch adds a CLREX or dummy STREX to the exception return path. This
is needed because several atomic/locking operations use a pair of
LDREX/STREXEQ and the EQ condition may not always be satisfied. This
would leave the exclusive monitor status set and may cause problems with
atomic/locking operations in the interrupted code.

With this patch, the atomic_set() operation can be a simple STR
instruction (on SMP systems, the global exclusive monitor is cleared by
STR anyway). Clearing the exclusive monitor during context switch is no
longer needed as this is handled by the exception return path anyway.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Jamie Lokier <jamie@shareable.org>
2009-09-18 23:30:11 +01:00
Catalin Marinas
b86040a59f Thumb-2: Implementation of the unified start-up and exceptions code
This patch implements the ARM/Thumb-2 unified kernel start-up and
exception handling code.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:32:54 +01:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Russell King
9c42954dfd [ARM] Move enable_irq and disable_irq to assembler.h
5d25ac038a broke VFP builds due to
enable_irq not being defined as an assembly macro.  Move it to
assembler.h so everyone can use it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-23 16:59:37 +00:00
Nicolas Pitre
2dede2d8e9 [ARM] 3102/1: ARM EABI: stack pointer must be 64-bit aligned after a CPU exception
Patch from Nicolas Pitre

The ARM EABI says that the stack pointer has to be 64-bit aligned for
reasons already mentioned in patch #3101 when calling C functions.

We therefore must verify and adjust sp accordingly when taking an
exception from kernel mode since sp might not necessarily be 64-bit
aligned if the exception occurs in the middle of a kernel function.

If the exception occurs while in user mode then no sp fixup is needed as
long as sizeof(struct pt_regs) as well as any additional syscall data
stack space remain multiples of 8.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-14 16:18:08 +00:00
Sam Ravnborg
e6ae744dd2 kbuild: arm - use generic asm-offsets.h support
Delete obsoleted stuff from arch Makefile and rename
constants.h to asm-offsets.h

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-09 21:08:59 +02:00
Russell King
49f680ea7b [PATCH] ARM SMP: convert alignment enable
The current vector entry system does not allow for SMP.  In
order to work around this, we need to eliminate our reliance
on the fixed save areas, which breaks the way we enable
alignment traps.  This patch makes the alignment trap enable
code independent of the way we handle the save areas.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-05-31 18:02:00 +01:00
Russell King
bce495d865 [PATCH] ARM: make entry*.S includes more logical
Move common includes to entry-header, and file specific includes
to the relevant file.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-26 15:21:02 +01:00
Russell King
f4dc9a4cf2 [PATCH] ARM: Remove single-use user save/restore macros
Assembly macros are pointless if they're only used once.  Move
them inline.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-26 15:20:34 +01:00
Russell King
cf88b417f9 [PATCH] ARM: remove PT_TRACESYS
PT_TRACESYS is unused, remove it.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-26 15:20:12 +01:00
Russell King
acaca3c915 [PATCH] ARM: Remove SVC_MODE definition
SVC_MODE reflects the MODE_SVC definition in asm/ptrace.h.  Use
the asm/ptrace.h definition instead, and remove SVC_MODE.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-26 15:19:48 +01:00
Russell King
e0f9f4a622 [PATCH] ARM: Use __NR_SYSCALL_BASE and __ARM_NR_BASE in asm code
Don't define our own local constants, but use those already defined
in asm/unistd.h instead.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-26 15:19:24 +01:00
Russell King
925c8a1a8c [PATCH] ARM: pt_regs offsets
Generate pt_regs S_xx offsets from the structure itself instead
of #defining them.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-26 15:18:59 +01:00
Russell King
1ec42c0c97 [PATCH] ARM: Remove argument for disable_irq/enable_irq
Since we do not require a register for these operations, we can
remove this unnecessary argument.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-26 15:18:26 +01:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00