[BUGFIX PATCH] kprobes/x86: Remove IRQ disabling from jprobe handlers

From: Masami Hiramatsu
Date: Tue Oct 03 2017 - 03:18:45 EST

Jprobe actually doesn't need to disable IRQs while calling
handlers, because Documentation/kprobes.txt says:

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@xxxxxxxxxx>
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 b48e0efd668e..bd36f3c33cd0 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -1099,8 +1099,6 @@ 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);