From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 89831CEBF61 for ; Mon, 17 Nov 2025 13:31:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=j4B/gAP/ehXLgCgUT9gdurkhU0EpobJjRCtEvQb5TWI=; b=tVmuWi0GfUY6LTMRetH5Cb32rK c5V/B+0nT4x6ILamP71m1dJosx9qwMxmQiazvxE2+UXi9+2jnT1QrJOpoqaX6cfmLTGoc2foPamUS JgAjXWDSz7shuSvcUp1ZEnwlre8rDMj48n6HYuMi0ZhFBP7s0XaNOaTr4FtLV6wAg2bBnyymKtyrz iSDJl1+o/DGNDTEpf91wi33O5/Ur1n3dKEJMhCWFweoA/X/V3R5AggXgmDIM8FH6MTtHU9nmsHFzH LpI3SYXruyCAwXFwN6luqY1u/vNms4ePalXSKZM0PmilwiXa/4Chm2jAWojFMw9gCQ7WZeq8/SJic R4yVlp3A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vKzKI-0000000GBB2-243q; Mon, 17 Nov 2025 13:31:26 +0000 Received: from canpmsgout02.his.huawei.com ([113.46.200.217]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vKzK8-0000000GB3E-04wY for linux-arm-kernel@lists.infradead.org; Mon, 17 Nov 2025 13:31:18 +0000 dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=j4B/gAP/ehXLgCgUT9gdurkhU0EpobJjRCtEvQb5TWI=; b=q6Peldem+vwkoD+lMi5B9Gj4HhqVKk1YxlBmQDtEu0vgWc+O3fc1W8rK1dO/IV+Pjr5iKT3CD uinNAdXLP6p3Gypam6dCXjtA+TiZmb5RcKowm6WEKGuMZuyhyPwk2L7LKDq3uZ6cqdzjOV7vvhm hXv60Skoy6tiIyydIpJDDc4= Received: from mail.maildlp.com (unknown [172.19.88.194]) by canpmsgout02.his.huawei.com (SkyGuard) with ESMTPS id 4d97r704KMzcbNS; Mon, 17 Nov 2025 21:29:11 +0800 (CST) Received: from dggpemf500011.china.huawei.com (unknown [7.185.36.131]) by mail.maildlp.com (Postfix) with ESMTPS id E3E3D140132; Mon, 17 Nov 2025 21:31:09 +0800 (CST) Received: from huawei.com (10.90.53.73) by dggpemf500011.china.huawei.com (7.185.36.131) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 17 Nov 2025 21:31:08 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , , , , , , , , , , , CC: Subject: [PATCH v7 03/11] arm64/ptrace: Refator el0_svc_common() Date: Mon, 17 Nov 2025 21:30:40 +0800 Message-ID: <20251117133048.53182-4-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20251117133048.53182-1-ruanjinjie@huawei.com> References: <20251117133048.53182-1-ruanjinjie@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.90.53.73] X-ClientProxiedBy: kwepems100002.china.huawei.com (7.221.188.206) To dggpemf500011.china.huawei.com (7.185.36.131) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251117_053116_421569_B7C5A27C X-CRM114-Status: GOOD ( 14.51 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Compared to the generic entry code, arm64 terminate the process after report_syscall_exit() if the syscall is issued within a restartable sequence. In preparation for moving arm64 over to the generic entry code, refactor el0_svc_common() as below: - Extract syscall_exit_to_user_mode_prepare() to replace the the combination of read_thread_flags() and syscall_trace_exit(), also move the syscall exit check logic into it. - Move rseq_syscall() ahead, so the CONFIG_DEBUG_RSEQ check is not needed. - Move has_syscall_work() helper into asm/syscall.h, which will be reused by ptrace.c. Signed-off-by: Jinjie Ruan --- arch/arm64/include/asm/syscall.h | 7 ++++++- arch/arm64/kernel/ptrace.c | 10 +++++++++- arch/arm64/kernel/syscall.c | 26 +++++--------------------- 3 files changed, 20 insertions(+), 23 deletions(-) diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h index d69f590a989b..6225981fbbdb 100644 --- a/arch/arm64/include/asm/syscall.h +++ b/arch/arm64/include/asm/syscall.h @@ -114,7 +114,12 @@ static inline int syscall_get_arch(struct task_struct *task) return AUDIT_ARCH_AARCH64; } +static inline bool has_syscall_work(unsigned long flags) +{ + return unlikely(flags & _TIF_SYSCALL_WORK); +} + int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long flags); -void syscall_trace_exit(struct pt_regs *regs, unsigned long flags); +void syscall_exit_to_user_mode_prepare(struct pt_regs *regs); #endif /* __ASM_SYSCALL_H */ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index bbb868f6b292..95984bbf53db 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -2403,7 +2403,7 @@ int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long flags) return regs->syscallno; } -void syscall_trace_exit(struct pt_regs *regs, unsigned long flags) +static void syscall_trace_exit(struct pt_regs *regs, unsigned long flags) { audit_syscall_exit(regs); @@ -2412,8 +2412,16 @@ void syscall_trace_exit(struct pt_regs *regs, unsigned long flags) if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP)) report_syscall_exit(regs); +} + +void syscall_exit_to_user_mode_prepare(struct pt_regs *regs) +{ + unsigned long flags = read_thread_flags(); rseq_syscall(regs); + + if (has_syscall_work(flags) || flags & _TIF_SINGLESTEP) + syscall_trace_exit(regs, flags); } /* diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c index 6e3fe760e0bb..9713b038d750 100644 --- a/arch/arm64/kernel/syscall.c +++ b/arch/arm64/kernel/syscall.c @@ -65,11 +65,6 @@ static void invoke_syscall(struct pt_regs *regs, unsigned int scno, choose_random_kstack_offset(get_random_u16()); } -static inline bool has_syscall_work(unsigned long flags) -{ - return unlikely(flags & _TIF_SYSCALL_WORK); -} - static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, const syscall_fn_t syscall_table[]) { @@ -125,26 +120,15 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, if (scno == NO_SYSCALL) syscall_set_return_value(current, regs, -ENOSYS, 0); scno = syscall_trace_enter(regs, regs->syscallno, flags); - if (scno == NO_SYSCALL) - goto trace_exit; + if (scno == NO_SYSCALL) { + syscall_exit_to_user_mode_prepare(regs); + return; + } } invoke_syscall(regs, scno, sc_nr, syscall_table); - /* - * The tracing status may have changed under our feet, so we have to - * check again. However, if we were tracing entry, then we always trace - * exit regardless, as the old entry assembly did. - */ - if (!has_syscall_work(flags) && !IS_ENABLED(CONFIG_DEBUG_RSEQ)) { - flags = read_thread_flags(); - if (!has_syscall_work(flags) && !(flags & _TIF_SINGLESTEP)) - return; - } - -trace_exit: - flags = read_thread_flags(); - syscall_trace_exit(regs, flags); + syscall_exit_to_user_mode_prepare(regs); } void do_el0_svc(struct pt_regs *regs) -- 2.34.1