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| author | K.Prasad <prasad@linux.vnet.ibm.com> | 2010-06-15 08:05:31 +0200 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2010-06-22 11:40:50 +0200 |
| commit | 2538c2d08f46141550a1e68819efa8fe31c6e3dc (patch) | |
| tree | c84255fa8dbc9446d4ff546988adabc12450b880 /arch | |
| parent | powerpc, hw_breakpoints: Implement hw_breakpoints for 64-bit server processors (diff) | |
| download | linux-2538c2d08f46141550a1e68819efa8fe31c6e3dc.tar.xz linux-2538c2d08f46141550a1e68819efa8fe31c6e3dc.zip | |
powerpc, hw_breakpoint: Handle concurrent alignment interrupts
If an alignment interrupt occurs on an instruction that is being
single-stepped, the alignment interrupt handler currently handles
the single-step condition by unconditionally sending a SIGTRAP to
the process. Other synchronous interrupts that result in the
instruction being emulated do likewise.
With hw_breakpoint support, the hw_breakpoint code needs to be able
to intercept these single-step events as well as those where the
instruction executes normally and a trace interrupt happens.
Fix this by making emulate_single_step() use the existing
single_step_exception() function instead of calling _exception()
directly. We then make single_step_exception() use the abstracted
clear_single_step() rather than clearing bits in the MSR image
directly so that emulate_single_step() will continue to work
correctly on Book 3E processors.
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/traps.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 25fc33984c2b..e5fe5a8522a6 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -688,7 +688,7 @@ void RunModeException(struct pt_regs *regs) void __kprobes single_step_exception(struct pt_regs *regs) { - regs->msr &= ~(MSR_SE | MSR_BE); /* Turn off 'trace' bits */ + clear_single_step(regs); if (notify_die(DIE_SSTEP, "single_step", regs, 5, 5, SIGTRAP) == NOTIFY_STOP) @@ -707,10 +707,8 @@ void __kprobes single_step_exception(struct pt_regs *regs) */ static void emulate_single_step(struct pt_regs *regs) { - if (single_stepping(regs)) { - clear_single_step(regs); - _exception(SIGTRAP, regs, TRAP_TRACE, 0); - } + if (single_stepping(regs)) + single_step_exception(regs); } static inline int __parse_fpscr(unsigned long fpscr) |