linux/arch/arc
Vineet Gupta 5b24282846 ARC: Ignore ptrace SETREGSET request for synthetic register "stop_pc"
ARCompact TRAP_S insn used for breakpoints, commits before exception is
taken (updating architectural PC). So ptregs->ret contains next-PC and
not the breakpoint PC itself. This is different from other restartable
exceptions such as TLB Miss where ptregs->ret has exact faulting PC.
gdb needs to know exact-PC hence ARC ptrace GETREGSET provides for
@stop_pc which returns ptregs->ret vs. EFA depending on the
situation.

However, writing stop_pc (SETREGSET request), which updates ptregs->ret
doesn't makes sense stop_pc doesn't always correspond to that reg as
described above.

This was not an issue so far since user_regs->ret / user_regs->stop_pc
had same value and both writing to ptregs->ret was OK, needless, but NOT
broken, hence not observed.

With gdb "jump", they diverge, and user_regs->ret updating ptregs is
overwritten immediately with stop_pc, which this patch fixes.

Reported-by: Anton Kolesov <akolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-10-12 12:00:36 +05:30
..
boot ARC: Add some .gitignore entries 2013-08-26 09:40:24 +05:30
configs Couple of Platform updates (Device Tree files primarily) given that the 2013-07-10 10:11:26 -07:00
include ARC: Workaround spinlock livelock in SMP SystemC simulation 2013-09-27 16:28:48 +05:30
kernel ARC: Ignore ptrace SETREGSET request for synthetic register "stop_pc" 2013-10-12 12:00:36 +05:30
lib ARC: [lib] strchr breakage in Big-endian configuration 2013-08-24 11:24:53 -07:00
mm arch: mm: pass userspace fault flag to generic fault handler 2013-09-12 15:38:01 -07:00
oprofile ARC: OProfile support 2013-02-15 23:16:00 +05:30
plat-arcfpga Couple of Platform updates (Device Tree files primarily) given that the 2013-07-10 10:11:26 -07:00
plat-tb10x ARC: [TB10x] Updates for irqchip driver 2013-06-28 15:07:42 +05:30
Kbuild ARC: Build system: Makefiles, Kconfig, Linker script 2013-02-11 20:00:25 +05:30
Kconfig Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
Kconfig.debug consolidate per-arch stack overflow debugging options 2013-07-04 11:25:39 -07:00
Makefile ARC: Adjustments for gcc 4.8 2013-06-27 14:35:32 +05:30