From patchwork Tue Jul 9 09:55:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiezhu Yang X-Patchwork-Id: 13727569 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 69241C2BD09 for ; Tue, 9 Jul 2024 09:55:42 +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-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=M81qIK8Yw2ugHw/bnj1mFGMn5DIv5tzYwD8MX/Gjjzo=; b=NdhtrhNn9P5X9Jhg92DyRyRqTV x626me4JazuQ82zPyNITGM1qyVuVU93k5WWfe+0kq5aztQ4uPTkKOPptZ7FburYWMGgQgoxfaYh4n in5SLLvSyuD9iFcfj7BllD8G6pGj5AwJqYuSnG2rpCFEsuUBuO2c87swmSfdZoSPJa58zY8Ax04qq 07YA9MzBlYabQdlmFP5M9j43Xd4sbkxcP5gHqCtbkTy6cKxKbj+IuJFNrdl02a4tm+8pshNvKHQbx ALbfvz9gHNwlORLrgCfUTEx9hqLMrE5Mag11wfhsI364B0tjFVdnSDOPRA095eU92lb/AdKtf//MR Hxo6E9Rg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sR7ZI-00000006hIR-2Al0; Tue, 09 Jul 2024 09:55:28 +0000 Received: from mail.loongson.cn ([114.242.206.163]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sR7Z2-00000006hD8-0NB6 for linux-arm-kernel@lists.infradead.org; Tue, 09 Jul 2024 09:55:14 +0000 Received: from loongson.cn (unknown [113.200.148.30]) by gateway (Coremail) with SMTP id _____8DxzfD9CI1mYmACAA--.7493S3; Tue, 09 Jul 2024 17:55:09 +0800 (CST) Received: from linux.localdomain (unknown [113.200.148.30]) by localhost.localdomain (Coremail) with SMTP id AQAAf8Cxqsb6CI1mgt1AAA--.17645S5; Tue, 09 Jul 2024 17:55:09 +0800 (CST) From: Tiezhu Yang To: Will Deacon , Mark Rutland , Russell King , Catalin Marinas , Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim Cc: linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 3/3] arm64: hw_breakpoint: Save privilege of access control via ptrace Date: Tue, 9 Jul 2024 17:55:06 +0800 Message-ID: <20240709095506.9691-4-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20240709095506.9691-1-yangtiezhu@loongson.cn> References: <20240709095506.9691-1-yangtiezhu@loongson.cn> MIME-Version: 1.0 X-CM-TRANSID: AQAAf8Cxqsb6CI1mgt1AAA--.17645S5 X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ X-Coremail-Antispam: 1Uk129KBj93XoW7CF18JryDGr4kur18ZrWrJFc_yoW8tw4Dpr ZxAw1qqw4UGa1UGayaqws3Zan8GwsFgryUXryDG3ySkr15Zr1fWrykGrnxurZ3JrW0q3y0 v3yDXr15Wa17X3XCm3ZEXasCq-sJn29KB7ZKAUJUUUU7529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUB2b4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1Y6r17M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVWxJr0_GcWln4kS14v26r1Y6r17M2AIxVAIcxkEcVAq07x20xvEncxIr21l57IF6xkI12 xvs2x26I8E6xACxx1l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1q 6rW5McIj6I8E87Iv67AKxVW8JVWxJwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64 vIr41lc7CjxVAaw2AFwI0_JF0_Jw1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_ Jr0_Gr1l4IxYO2xFxVAFwI0_Jrv_JF1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8Gjc xK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0 cI8IcVAFwI0_Xr0_Ar1lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8V AvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87Iv6xkF7I0E 14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxUxhiSDUUUU X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240709_025512_494370_C60EE745 X-CRM114-Status: GOOD ( 15.86 ) 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 In the current code, decode_ctrl_reg() saves the privilege of access control passed by the ptrace user data, but it is not used anymore, arch_build_bp_info() checks whether bp virtual address is in kernel space to construct hw->ctrl.privilege, it seems not reasonable. The value of ctrl->privilege saved in decode_ctrl_reg() can be used in arch_build_bp_info(), there is no need to check bp virtual address to assign value for hw->ctrl.privilege, just make use of "bp_priv" in the struct perf_event_attr to save the privilege of access control via ptrace for hardware breakpoint. Signed-off-by: Tiezhu Yang --- arch/arm64/kernel/hw_breakpoint.c | 11 ++--------- arch/arm64/kernel/ptrace.c | 2 ++ 2 files changed, 4 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index 722ac45f9f7b..06e34bcdcf92 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c @@ -486,15 +486,8 @@ static int arch_build_bp_info(struct perf_event *bp, /* Address */ hw->address = attr->bp_addr; - /* - * Privilege - * Note that we disallow combined EL0/EL1 breakpoints because - * that would complicate the stepping code. - */ - if (arch_check_bp_in_kernelspace(hw)) - hw->ctrl.privilege = AARCH64_BREAKPOINT_EL1; - else - hw->ctrl.privilege = AARCH64_BREAKPOINT_EL0; + /* Privilege */ + hw->ctrl.privilege = attr->bp_priv; /* Enabled? */ hw->ctrl.enabled = !attr->disabled; diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 0d022599eb61..3b37c4a2e0d4 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -309,6 +309,7 @@ static struct perf_event *ptrace_hbp_create(unsigned int note_type, attr.bp_addr = 0; attr.bp_len = HW_BREAKPOINT_LEN_4; attr.bp_type = type; + attr.bp_priv = AARCH64_BREAKPOINT_EL0; attr.disabled = 1; bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk); @@ -352,6 +353,7 @@ static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type, attr->bp_len = len; attr->bp_type = type; attr->bp_addr += offset; + attr->bp_priv = ctrl.privilege; return 0; }