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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BEF90C04AB5 for ; Mon, 3 Jun 2019 15:02:54 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8B1A325A49 for ; Mon, 3 Jun 2019 15:02:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="DynfSc7E" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B1A325A49 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:36250 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hXoU9-0008Tl-Kv for qemu-devel@archiver.kernel.org; Mon, 03 Jun 2019 11:02:53 -0400 Received: from eggs.gnu.org ([209.51.188.92]:39051) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hXoSt-0007iN-Eu for qemu-devel@nongnu.org; Mon, 03 Jun 2019 11:01:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hXoSp-0003sg-20 for qemu-devel@nongnu.org; Mon, 03 Jun 2019 11:01:33 -0400 Received: from mail-wm1-x341.google.com ([2a00:1450:4864:20::341]:39626) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hXoSn-0003lP-K5 for qemu-devel@nongnu.org; Mon, 03 Jun 2019 11:01:30 -0400 Received: by mail-wm1-x341.google.com with SMTP id z23so11446187wma.4 for ; Mon, 03 Jun 2019 08:01:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=VyhF5x0WzFov9r43y8si0eLCX0eXOqkE4ayiLm7MPMI=; b=DynfSc7EL7hZN/zwitvwwfWkq09dOSgZxOTnsDW9VQ/Up2lRvd580+rvR+fYmAr4L/ K5BRNZkA/r+Q81tk7ohVY8yGz3BN/OrJlfvAlFdTD61dru560s52yJh/ushATBYZaiBD bP01b9LAdxR5r8Q4SJOuZEtN/luvUaI5ZLGR1esH4liaOkvvTgwRLDTfUjX4Jv0d1lSE NbqfQPTTkBOuShRIOOPfy+9vTrXHY6nR5Glj4J1OeMBsw39wJlI2jjWWXksfBEFBrv1w q3WNE8X8m6+I2PIT/tDrIVyhKCvP/kMkJRN41q37kSa+e1thUH/LQ/lArHh/c83g+WDx eOOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=VyhF5x0WzFov9r43y8si0eLCX0eXOqkE4ayiLm7MPMI=; b=e0Zz16MPnxwNcLje7hx7RXX+K7ut4pfY9w2yuJ4yoZoxXtQcGFCcnGCySYgRLdAwhO jBqZW3MNj2neLriJYUKiEB7kE8DTk6uXwx1q5orjVvmvQW8z0HlCR5zAmTNk6rLu7Yda TcCWjjDmlRp439Ub2XmnP6gXx0yvLPmfgGfZ+smObM5nCDNElHcbczlyFcj6hVY+iY9E yTCgbnVQmdRC8cHST7Hh1MmDCHhJahaTGW+PN/tApdGmZ2nMWQJNI8R9FFu0pf3XJGNT 2h5HEyuDSKUoZzkrObyomRcR/qtJnPoAFiGh2e0GyRcq0E5GeLaprIxuMmwQjlfT9Huk UNDg== X-Gm-Message-State: APjAAAWuXQpUv+pZXzv6tP/jtRcusHAYJomIHA5bWirm3CZnnRQ3gq+2 V/sCg60+EJ6FQI/gjBxY76Z/FQ== X-Google-Smtp-Source: APXvYqxmeE+L9QrX6MYixllSnParujoSQRrE27rvx0DbgPCPaomHFBoWHywjGLAGISapLgNp2apTWQ== X-Received: by 2002:a1c:5687:: with SMTP id k129mr14050053wmb.133.1559574086490; Mon, 03 Jun 2019 08:01:26 -0700 (PDT) Received: from zen.linaroharston ([81.128.185.34]) by smtp.gmail.com with ESMTPSA id p2sm5412769wrx.90.2019.06.03.08.01.25 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Mon, 03 Jun 2019 08:01:25 -0700 (PDT) Received: from zen.linaroharston. (localhost [127.0.0.1]) by zen.linaroharston (Postfix) with ESMTP id 5EEDC1FF87; Mon, 3 Jun 2019 16:01:25 +0100 (BST) From: =?UTF-8?q?Alex=20Benn=C3=A9e?= To: qemu-devel@nongnu.org Date: Mon, 3 Jun 2019 16:01:20 +0100 Message-Id: <20190603150120.29255-1-alex.bennee@linaro.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2a00:1450:4864:20::341 Subject: [Qemu-devel] [RFC PATCH] cputlb: use uint64_t for interim values for unaligned load X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: 1830872@bugs.launchpad.net, qemu-arm@nongnu.org, Paolo Bonzini , =?UTF-8?q?Alex=20Benn=C3=A9e?= , randrianasulu@gmail.com, Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" When running on 32 bit TCG backends a wide unaligned load ends up truncating data before returning to the guest. We specifically have the return type as uint64_t to avoid any premature truncation so we should use the same for the interim types. Hopefully fixes #1830872 Signed-off-by: Alex Bennée --- accel/tcg/cputlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c index cdcc3771020..b796ab1cbea 100644 --- a/accel/tcg/cputlb.c +++ b/accel/tcg/cputlb.c @@ -1303,7 +1303,7 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi, && unlikely((addr & ~TARGET_PAGE_MASK) + size - 1 >= TARGET_PAGE_SIZE)) { target_ulong addr1, addr2; - tcg_target_ulong r1, r2; + uint64_t r1, r2; unsigned shift; do_unaligned_access: addr1 = addr & ~(size - 1); -- 2.20.1 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 X-Spam-Level: X-Spam-Status: No, score=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 70317C04AB5 for ; Mon, 3 Jun 2019 15:29:14 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 386CC2775D for ; Mon, 3 Jun 2019 15:29:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 386CC2775D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:36699 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hXotd-0004PK-Ft for qemu-devel@archiver.kernel.org; Mon, 03 Jun 2019 11:29:13 -0400 Received: from eggs.gnu.org ([209.51.188.92]:47116) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hXorn-0002w0-II for qemu-devel@nongnu.org; Mon, 03 Jun 2019 11:27:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hXobi-000479-Qn for qemu-devel@nongnu.org; Mon, 03 Jun 2019 11:10:44 -0400 Received: from indium.canonical.com ([91.189.90.7]:49432) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hXobi-000437-KY for qemu-devel@nongnu.org; Mon, 03 Jun 2019 11:10:42 -0400 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.86_2 #2 (Debian)) id 1hXobh-0003ed-5d for ; Mon, 03 Jun 2019 15:10:41 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id 2491E2E80C8 for ; Mon, 3 Jun 2019 15:10:41 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Date: Mon, 03 Jun 2019 15:01:20 -0000 From: =?utf-8?q?Alex_Benn=C3=A9e?= To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=New; importance=Undecided; assignee=None; X-Launchpad-Bug-Tags: arm testcase X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: ajbennee lersek X-Launchpad-Bug-Reporter: Laszlo Ersek (Red Hat) (lersek) X-Launchpad-Bug-Modifier: =?utf-8?q?Alex_Benn=C3=A9e_=28ajbennee=29?= References: <155912118291.12579.8926874795813611531.malonedeb@soybean.canonical.com> Message-Id: <20190603150120.29255-1-alex.bennee@linaro.org> X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="18968"; Instance="launchpad-lazr.conf" X-Launchpad-Hash: e1ddb2402fc20e609bf408b19bdb8a2b2dc1519c X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 91.189.90.7 Subject: [Qemu-devel] [Bug 1830872] [RFC PATCH] cputlb: use uint64_t for interim values for unaligned load X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1830872 <1830872@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Message-ID: <20190603150120.sggjJ6_JyEdYCKImGca9hRMEi4zPB5eN1dA_p1wemDQ@z> When running on 32 bit TCG backends a wide unaligned load ends up truncating data before returning to the guest. We specifically have the return type as uint64_t to avoid any premature truncation so we should use the same for the interim types. Hopefully fixes #1830872 Signed-off-by: Alex Benn=C3=A9e --- accel/tcg/cputlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c index cdcc3771020..b796ab1cbea 100644 --- a/accel/tcg/cputlb.c +++ b/accel/tcg/cputlb.c @@ -1303,7 +1303,7 @@ load_helper(CPUArchState *env, target_ulong addr, TCG= MemOpIdx oi, && unlikely((addr & ~TARGET_PAGE_MASK) + size - 1 >=3D TARGET_PAGE_SIZE)) { target_ulong addr1, addr2; - tcg_target_ulong r1, r2; + uint64_t r1, r2; unsigned shift; do_unaligned_access: addr1 =3D addr & ~(size - 1); -- = 2.20.1 -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1830872 Title: AARCH64 to ARMv7 mistranslation in TCG Status in QEMU: New Bug description: The following guest code: https://github.com/tianocore/edk2/blob/3604174718e2afc950c3cc64c64ba5165c= 8692bd/MdePkg/Library/BaseMemoryLibOptDxe/AArch64/CopyMem.S implements, in hand-optimized aarch64 assembly, the CopyMem() edk2 (EFI Development Kit II) library function. (CopyMem() basically has memmove() semantics, to provide a standard C analog here.) The relevant functions are InternalMemCopyMem() and __memcpy(). When TCG translates this aarch64 code to x86_64, everything works fine. When TCG translates this aarch64 code to ARMv7, the destination area of the translated CopyMem() function becomes corrupted -- it differs from the intended source contents. Namely, in every 4096 byte block, the 8-byte word at offset 4032 (0xFC0) is zeroed out in the destination, instead of receiving the intended source value. I'm attaching two hexdumps of the same destination area: - "good.txt" is a hexdump of the destination area when CopyMem() was translated to x86_64, - "bad.txt" is a hexdump of the destination area when CopyMem() was translated to ARMv7. In order to assist with the analysis of this issue, I disassembled the aarch64 binary with "objdump". Please find the listing in "DxeCore.objdump", attached. The InternalMemCopyMem() function starts at hex offset 2b2ec. The __memcpy() function starts at hex offset 2b180. And, I ran the guest on the ARMv7 host with "-d in_asm,op,op_opt,op_ind,out_asm". Please find the log in "tcg.in_asm.op.op_opt.op_ind.out_asm.log", attached. The TBs that correspond to (parts of) the InternalMemCopyMem() and __memcpy() functions are scattered over the TCG log file, but the offset between the "nice" disassembly from "DxeCore.objdump", and the in-RAM TBs in the TCG log, can be determined from the fact that there is a single prfm instruction in the entire binary. The instruction's offset is 0x2b180 in "DxeCore.objdump" -- at the beginning of the __memcpy() function --, and its RAM address is 0x472d2180 in the TCG log. Thus the difference (=3D the load address of DxeCore.efi) is 0x472a7000. QEMU was built at commit a4f667b67149 ("Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20190521-3' into staging", 2019-05-21). The reproducer command line is (on an ARMv7 host): qemu-system-aarch64 \ -display none \ -machine virt,accel=3Dtcg \ -nodefaults \ -nographic \ -drive if=3Dpflash,format=3Draw,file=3D$prefix/share/qemu/edk2-aarch6= 4-code.fd,readonly \ -drive if=3Dpflash,format=3Draw,file=3D$prefix/share/qemu/edk2-arm-va= rs.fd,snapshot=3Don \ -cpu cortex-a57 \ -chardev stdio,signal=3Doff,mux=3Don,id=3Dchar0 \ -mon chardev=3Dchar0,mode=3Dreadline \ -serial chardev:char0 The apparent symptom is an assertion failure *in the guest*, such as > ASSERT [DxeCore] > /home/lacos/src/upstream/qemu/roms/edk2/MdePkg/Library/BaseLib/String.c= (1090): > Length < _gPcd_FixedAtBuild_PcdMaximumAsciiStringLength but that is only a (distant) consequence of the CopyMem() mistranslation, and resultant destination area corruption. Originally reported in the following two mailing list messages: - http://mid.mail-archive.com/9d2e260c-c491-03d2-9b8b-b57b72083f77@redhat= .com - http://mid.mail-archive.com/f1cec8c0-1a9b-f5bb-f951-ea0ba9d276ee@redhat= .com To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1830872/+subscriptions