From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Tue, 26 Aug 2014 15:13:30 +0100 Subject: [PATCH 11/11] arm64: perf: don't rely on layout of pt_regs when grabbing sp or pc In-Reply-To: <1409062410-25891-1-git-send-email-will.deacon@arm.com> References: <1409062410-25891-1-git-send-email-will.deacon@arm.com> Message-ID: <1409062410-25891-12-git-send-email-will.deacon@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The current perf_regs code relies on sp and pc sitting just off the end of the pt_regs->regs array. This is ugly and fragile, so this patch checks for these register explicitly and returns the appropriate field. Cc: Jean Pihet Signed-off-by: Will Deacon --- arch/arm64/kernel/perf_regs.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/arm64/kernel/perf_regs.c b/arch/arm64/kernel/perf_regs.c index 422ebd63b619..6762ad705587 100644 --- a/arch/arm64/kernel/perf_regs.c +++ b/arch/arm64/kernel/perf_regs.c @@ -24,6 +24,12 @@ u64 perf_reg_value(struct pt_regs *regs, int idx) return regs->compat_lr; } + if ((u32)idx == PERF_REG_ARM64_SP) + return regs->sp; + + if ((u32)idx == PERF_REG_ARM64_PC) + return regs->pc; + return regs->regs[idx]; } -- 2.1.0.rc1