diff options
| author | Will Deacon <will.deacon@arm.com> | 2016-07-19 15:07:39 +0100 |
|---|---|---|
| committer | Alex Shi <alex.shi@linaro.org> | 2016-10-20 15:38:13 +0800 |
| commit | a1961c0da3b0e3fa8bd803547f96963bf31b69a4 (patch) | |
| tree | 5c60572ea4eaa2e59582ea0651c3d5402bc573c8 /arch/arm64/kernel | |
| parent | da367d1e9e36ed55023a59a7fbcb3541732c2eff (diff) | |
arm64: kprobes: WARN if attempting to step with PSTATE.D=1
commit 44bd887ce10eb8061f6a137f8a73f823957edd82 upstream.
Stepping with PSTATE.D=1 is bad news. The step won't generate a debug
exception and we'll likely walk off into random data structures. This
should never happen, but when it does, it's a PITA to debug. Add a
WARN_ON to shout if we realise this is about to take place.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/probes/kprobes.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index f1498b34d1c7..a9b274c99519 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -251,6 +251,8 @@ static void __kprobes setup_singlestep(struct kprobe *p, if (kcb->kprobe_status == KPROBE_REENTER) spsr_set_debug_flag(regs, 0); + else + WARN_ON(regs->pstate & PSR_D_BIT); /* IRQs and single stepping do not mix well. */ kprobes_save_local_irqflag(kcb, regs); |