From mboxrd@z Thu Jan 1 00:00:00 1970 From: jistone@redhat.com (Josh Stone) Date: Mon, 22 Jun 2015 17:08:54 -0700 Subject: [PATCH] ARM: enable_irq before ret_fast_syscall tracing In-Reply-To: <20150604100625.GI7557@n2100.arm.linux.org.uk> References: <20150604100625.GI7557@n2100.arm.linux.org.uk> Message-ID: <1435018134-9653-1-git-send-email-jistone@redhat.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org When reached via the slow path __sys_trace, __sys_trace_return and its callees usually have interrupts still enabled. This is important if any will schedule, like for a ptrace syscall-exit-stop. In the rarer case where tracing was not enabled on syscall entry, and then ret_fast_syscall sees tracing was enabled mid-syscall, then it also ought to branch to __sys_trace_return with interrupts enabled. Cc: Russell King Signed-off-by: Josh Stone --- arch/arm/kernel/entry-common.S | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 4e7f40c577e6..5d8eb11b8571 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -35,7 +35,7 @@ ret_fast_syscall: disable_irq @ disable interrupts ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing tst r1, #_TIF_SYSCALL_WORK - bne __sys_trace_return + bne ret_fast_syscall_trace tst r1, #_TIF_WORK_MASK bne fast_work_pending asm_trace_hardirqs_on @@ -45,6 +45,10 @@ ret_fast_syscall: ct_user_enter restore_user_regs fast = 1, offset = S_OFF + +ret_fast_syscall_trace: + enable_irq @ enable interrupts + b __sys_trace_return UNWIND(.fnend ) /* -- 2.4.2