From patchwork Wed Apr 6 09:13:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tong Tiangen X-Patchwork-Id: 12802726 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 9799DC433F5 for ; Wed, 6 Apr 2022 08:56:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id: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=ROO9NSLTDdVVZ8Kv1N+wRzV2MvduFF7DA6PYOrz0e9w=; b=IfjyKrXXoqO9fi GRFIMtTdd0parZPzLJ+YFWlFQETu6lN/cdBqZpUkRhGLoKbvffhryH98cFQM7WWpgk3a2AMkmdx40 4qejDZrUDuGnKhGoZoP0RQlRwCxyu/QzWINp+I69xCICtZIznpK5vPmA9Jp/zNMoD4atPqrtntzPd Iy8Az8oOay+ajeqZ9C8mbrqiIB+6EcvKszKGcmS8zW3Z797I1/893NtX2q8bZ4RWeM7u9kL4H9swZ T53ktotpqdrIeRO6ZAZkwHXtIFGpbhNShiMqKqEoDD2p9ug3bkqExpPGrETgPj3+5XYAiSqfkJXW+ aswTi1cChngTMhlcWXog==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nc1Ra-004qUY-4i; Wed, 06 Apr 2022 08:55:14 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nc1Qu-004qCG-Hm for linux-arm-kernel@lists.infradead.org; Wed, 06 Apr 2022 08:54:34 +0000 Received: from kwepemi100009.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4KYJGM5tRfzdZZq; Wed, 6 Apr 2022 16:54:03 +0800 (CST) Received: from kwepemm600017.china.huawei.com (7.193.23.234) by kwepemi100009.china.huawei.com (7.221.188.242) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 6 Apr 2022 16:54:30 +0800 Received: from localhost.localdomain (10.175.112.125) by kwepemm600017.china.huawei.com (7.193.23.234) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Wed, 6 Apr 2022 16:54:29 +0800 From: Tong Tiangen To: Andrew Morton , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Catalin Marinas , Will Deacon , Alexander Viro , , "H. Peter Anvin" CC: , , , Tong Tiangen Subject: [RFC PATCH -next V2 4/7] arm64: add copy_from_user to machine check safe Date: Wed, 6 Apr 2022 09:13:08 +0000 Message-ID: <20220406091311.3354723-5-tongtiangen@huawei.com> X-Mailer: git-send-email 2.18.0.huawei.25 In-Reply-To: <20220406091311.3354723-1-tongtiangen@huawei.com> References: <20220406091311.3354723-1-tongtiangen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.112.125] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemm600017.china.huawei.com (7.193.23.234) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220406_015432_982493_81F794BF X-CRM114-Status: GOOD ( 10.49 ) 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 Add scenarios copy_from_user to machine check safe. The data copied is user data and is machine check safe, so just kill the user process and isolate the error page, not necessary panic. Signed-off-by: Tong Tiangen --- arch/arm64/include/asm/asm-uaccess.h | 16 ++++++++++++++++ arch/arm64/lib/copy_from_user.S | 11 ++++++----- 2 files changed, 22 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/asm-uaccess.h b/arch/arm64/include/asm/asm-uaccess.h index 0557af834e03..f31c8978e1af 100644 --- a/arch/arm64/include/asm/asm-uaccess.h +++ b/arch/arm64/include/asm/asm-uaccess.h @@ -92,4 +92,20 @@ alternative_else_nop_endif _asm_extable 8888b,\l; .endm + + .macro user_ldp_mc l, reg1, reg2, addr, post_inc +8888: ldtr \reg1, [\addr]; +8889: ldtr \reg2, [\addr, #8]; + add \addr, \addr, \post_inc; + + _asm_extable_mc 8888b, \l; + _asm_extable_mc 8889b, \l; + .endm + + .macro user_ldst_mc l, inst, reg, addr, post_inc +8888: \inst \reg, [\addr]; + add \addr, \addr, \post_inc; + + _asm_extable_mc 8888b, \l; + .endm #endif diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 34e317907524..d9d7c5291871 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -21,7 +21,7 @@ */ .macro ldrb1 reg, ptr, val - user_ldst 9998f, ldtrb, \reg, \ptr, \val + user_ldst_mc 9998f, ldtrb, \reg, \ptr, \val .endm .macro strb1 reg, ptr, val @@ -29,7 +29,7 @@ .endm .macro ldrh1 reg, ptr, val - user_ldst 9997f, ldtrh, \reg, \ptr, \val + user_ldst_mc 9997f, ldtrh, \reg, \ptr, \val .endm .macro strh1 reg, ptr, val @@ -37,7 +37,7 @@ .endm .macro ldr1 reg, ptr, val - user_ldst 9997f, ldtr, \reg, \ptr, \val + user_ldst_mc 9997f, ldtr, \reg, \ptr, \val .endm .macro str1 reg, ptr, val @@ -45,7 +45,7 @@ .endm .macro ldp1 reg1, reg2, ptr, val - user_ldp 9997f, \reg1, \reg2, \ptr, \val + user_ldp_mc 9997f, \reg1, \reg2, \ptr, \val .endm .macro stp1 reg1, reg2, ptr, val @@ -62,7 +62,8 @@ SYM_FUNC_START(__arch_copy_from_user) ret // Exception fixups -9997: cmp dst, dstin +9997: cbz x0, 9998f // Check machine check exception + cmp dst, dstin b.ne 9998f // Before being absolutely sure we couldn't copy anything, try harder USER(9998f, ldtrb tmp1w, [srcin])