From: Zhen Lei thunder.leizhen@huawei.com
[ Upstream commit a506bd5756290821a4314f502b4bafc2afcf5260 ]
The commit 1879445dfa7b ("perf/core: Set event's default ::overflow_handler()") set a default event->overflow_handler in perf_event_alloc(), and replace the check event->overflow_handler with is_default_overflow_handler(), but one is missing.
Currently, the bp->overflow_handler can not be NULL. As a result, enable_single_step() is always not invoked.
Comments from Zhen Lei:
https://patchwork.kernel.org/project/linux-arm-kernel/patch/20210207105934.2...
Fixes: 1879445dfa7b ("perf/core: Set event's default ::overflow_handler()") Signed-off-by: Zhen Lei thunder.leizhen@huawei.com Cc: Wang Nan wangnan0@huawei.com Acked-by: Will Deacon will@kernel.org Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/kernel/hw_breakpoint.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index e61697fb7efe..a8783964ebde 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -891,7 +891,7 @@ static void breakpoint_handler(unsigned long unknown, struct pt_regs *regs) info->trigger = addr; pr_debug("breakpoint fired: address = 0x%x\n", addr); perf_bp_event(bp, regs); - if (!bp->overflow_handler) + if (is_default_overflow_handler(bp)) enable_single_step(bp, addr); goto unlock; }