From mboxrd@z Thu Jan 1 00:00:00 1970 From: guoren@kernel.org Subject: [PATCH] csky: Fixup CONFIG_DEBUG_RSEQ Date: Thu, 28 May 2020 08:14:29 +0800 Message-ID: <1590624869-6594-1-git-send-email-guoren@kernel.org> Return-path: Received: from mail.kernel.org ([198.145.29.99]:51708 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725819AbgE1AOn (ORCPT ); Wed, 27 May 2020 20:14:43 -0400 Sender: linux-arch-owner@vger.kernel.org List-ID: To: arnd@arndb.de Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-csky@vger.kernel.org, Guo Ren From: Guo Ren Put the rseq_syscall check point at the prologue of the syscall will break the a0 ... a7. This will casue system call bug when DEBUG_RSEQ is enabled. So move it to the epilogue of syscall, but before syscall_trace. Signed-off-by: Guo Ren --- arch/csky/kernel/entry.S | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S index 9595e86..f138003 100644 --- a/arch/csky/kernel/entry.S +++ b/arch/csky/kernel/entry.S @@ -128,15 +128,11 @@ tlbop_end 1 ENTRY(csky_systemcall) SAVE_ALL TRAP0_SIZE zero_fp -#ifdef CONFIG_RSEQ_DEBUG - mov a0, sp - jbsr rseq_syscall -#endif psrset ee, ie lrw r9, __NR_syscalls cmphs syscallid, r9 /* Check nr of syscall */ - bt ret_from_exception + bt 1f lrw r9, sys_call_table ixw r9, syscallid @@ -162,6 +158,11 @@ ENTRY(csky_systemcall) jsr syscallid #endif stw a0, (sp, LSAVE_A0) /* Save return value */ +1: +#ifdef CONFIG_DEBUG_RSEQ + mov a0, sp + jbsr rseq_syscall +#endif jmpi ret_from_exception csky_syscall_trace: @@ -187,6 +188,10 @@ csky_syscall_trace: #endif stw a0, (sp, LSAVE_A0) /* Save return value */ +#ifdef CONFIG_DEBUG_RSEQ + mov a0, sp + jbsr rseq_syscall +#endif mov a0, sp /* right now, sp --> pt_regs */ jbsr syscall_trace_exit br ret_from_exception -- 2.7.4