From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754625AbcGUVPm (ORCPT ); Thu, 21 Jul 2016 17:15:42 -0400 Received: from mail.efficios.com ([78.47.125.74]:52979 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754091AbcGUVP0 (ORCPT ); Thu, 21 Jul 2016 17:15:26 -0400 From: Mathieu Desnoyers To: Andrew Morton , Russell King , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Paul Turner , Andrew Hunter , Peter Zijlstra , Andy Lutomirski , Andi Kleen , Dave Watson , Chris Lameter , Ben Maurer , Steven Rostedt , "Paul E. McKenney" , Josh Triplett , Linus Torvalds , Catalin Marinas , Will Deacon , Michael Kerrisk , Boqun Feng , Mathieu Desnoyers Subject: [RFC PATCH v7 5/7] Restartable sequences: x86 32/64 architecture support Date: Thu, 21 Jul 2016 17:14:20 -0400 Message-Id: <1469135662-31512-6-git-send-email-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1469135662-31512-1-git-send-email-mathieu.desnoyers@efficios.com> References: <1469135662-31512-1-git-send-email-mathieu.desnoyers@efficios.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Call the rseq_handle_notify_resume() function on return to userspace if TIF_NOTIFY_RESUME thread flag is set. Increment the event counter and perform fixup on the pre-signal frame when a signal is delivered on top of a restartable sequence critical section. Signed-off-by: Mathieu Desnoyers CC: Russell King CC: Catalin Marinas CC: Will Deacon CC: Thomas Gleixner CC: Paul Turner CC: Andrew Hunter CC: Peter Zijlstra CC: Andy Lutomirski CC: Andi Kleen CC: Dave Watson CC: Chris Lameter CC: Ingo Molnar CC: "H. Peter Anvin" CC: Ben Maurer CC: Steven Rostedt CC: "Paul E. McKenney" CC: Josh Triplett CC: Linus Torvalds CC: Andrew Morton CC: Boqun Feng CC: linux-api@vger.kernel.org --- arch/x86/Kconfig | 1 + arch/x86/entry/common.c | 1 + arch/x86/kernel/signal.c | 6 ++++++ 3 files changed, 8 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d9a94da..1db7b06 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -140,6 +140,7 @@ config X86 select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP select HAVE_REGS_AND_STACK_ACCESS_API + select HAVE_RSEQ select HAVE_SYSCALL_TRACEPOINTS select HAVE_UID16 if X86_32 || IA32_EMULATION select HAVE_UNSTABLE_SCHED_CLOCK diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index ec138e5..3877dba 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -231,6 +231,7 @@ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags) if (cached_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); + rseq_handle_notify_resume(regs); } if (cached_flags & _TIF_USER_RETURN_NOTIFY) diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 22cc2f9..0f4da5a 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -683,6 +683,12 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) sigset_t *set = sigmask_to_save(); compat_sigset_t *cset = (compat_sigset_t *) set; + /* + * Increment event counter and perform fixup for the pre-signal + * frame. + */ + rseq_signal_deliver(regs); + /* Set up the stack frame */ if (is_ia32_frame()) { if (ksig->ka.sa.sa_flags & SA_SIGINFO) -- 2.1.4