From b664d57f39d01e775204d4f1a7e2f8bda77bc549 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu <mhiramat@kernel.org> Date: Tue, 3 Oct 2017 16:18:02 +0900 Subject: [PATCH] kprobes/x86: Remove IRQ disabling from jprobe handlers Jprobes actually don't need to disable IRQs while calling handlers, because of how we specify the kernel interface in Documentation/kprobes.txt: ----- Probe handlers are run with preemption disabled. Depending on the architecture and optimization state, handlers may also run with interrupts disabled (e.g., kretprobe handlers and optimized kprobe handlers run without interrupt disabled on x86/x86-64). ----- So let's remove IRQ disabling from jprobes too. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Alexei Starovoitov <ast@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/150701508194.32266.14458959863314097305.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/x86/kernel/kprobes/core.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index f0153714ddac..0742491cbb73 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -1080,8 +1080,6 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) * raw stack chunk with redzones: */ __memcpy(kcb->jprobes_stack, (kprobe_opcode_t *)addr, MIN_STACK_SIZE(addr)); - regs->flags &= ~X86_EFLAGS_IF; - trace_hardirqs_off(); regs->ip = (unsigned long)(jp->entry); /* -- GitLab