linux/arch
Russell King 15ac49b650 ARM: Fix undefined instruction exception handling
While trying to get a v3.5 kernel booted on the cubox, I noticed that
VFP does not work correctly with VFP bounce handling.  This is because
of the confusion over 16-bit vs 32-bit instructions, and where PC is
supposed to point to.

The rule is that FP handlers are entered with regs->ARM_pc pointing at
the _next_ instruction to be executed.  However, if the exception is
not handled, regs->ARM_pc points at the faulting instruction.

This is easy for ARM mode, because we know that the next instruction and
previous instructions are separated by four bytes.  This is not true of
Thumb2 though.

Since all FP instructions are 32-bit in Thumb2, it makes things easy.
We just need to select the appropriate adjustment.  Do this by moving
the adjustment out of do_undefinstr() into the assembly code, as only
the assembly code knows whether it's dealing with a 32-bit or 16-bit
instruction.

Cc: <stable@vger.kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-31 12:04:30 +01:00
..
alpha Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-06-01 11:53:44 -07:00
arm ARM: Fix undefined instruction exception handling 2012-07-31 12:04:30 +01:00
avr32 fixups for signal breakage 2012-06-04 17:47:34 -04:00
blackfin Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-06-05 09:47:15 -07:00
c6x new helper: signal_delivered() 2012-06-01 12:58:52 -04:00
cris Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-06-01 11:53:44 -07:00
frv frv: Remove bogus closing parenthesis 2012-06-02 10:38:19 -04:00
h8300 h8300: use the declarations provided by <asm/sections.h> 2012-06-20 14:39:35 -07:00
hexagon new helper: signal_delivered() 2012-06-01 12:58:52 -04:00
ia64 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-06-01 11:53:44 -07:00
m32r Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-06-01 11:53:44 -07:00
m68k m68knommu: define a local devm_clk_get() function 2012-06-25 09:17:20 +10:00
microblaze new helper: signal_delivered() 2012-06-01 12:58:52 -04:00
mips - More robust parsing especially of xattr data in JFFS2 2012-06-01 16:55:42 -07:00
mn10300 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-06-01 11:53:44 -07:00
openrisc new helper: signal_delivered() 2012-06-01 12:58:52 -04:00
parisc [PARISC] fix code to find libgcc 2012-06-05 14:10:23 +09:00
powerpc powerpc/kvm: sldi should be sld 2012-07-02 14:30:12 +10:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-06-01 11:53:44 -07:00
score new helper: signal_delivered() 2012-06-01 12:58:52 -04:00
sh Merge branches 'sh/urgent' and 'sh/trivial' into sh-fixes-for-linus 2012-06-28 16:46:13 +09:00
sparc Fix typo in printed messages 2012-06-24 11:03:52 -07:00
tile tile: fix bug in get_user() for 4-byte values 2012-06-16 16:56:13 -04:00
um new helper: signal_delivered() 2012-06-01 12:58:52 -04:00
unicore32 new helper: signal_delivered() 2012-06-01 12:58:52 -04:00
x86 KVM: MMU: fix shrinking page from the empty mmu 2012-07-03 17:31:50 -03:00
xtensa xtensa: use the declarations provided by <asm/sections.h> 2012-06-20 14:39:35 -07:00
.gitignore
Kconfig Merge branch 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping 2012-05-25 09:18:59 -07:00