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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 E8107C7EE22 for ; Tue, 9 May 2023 15:10:37 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pwOyL-00026L-44; Tue, 09 May 2023 11:09:49 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pwOyI-00025h-8N for qemu-devel@nongnu.org; Tue, 09 May 2023 11:09:46 -0400 Received: from mail-ed1-x52a.google.com ([2a00:1450:4864:20::52a]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1pwOyE-00062g-WB for qemu-devel@nongnu.org; Tue, 09 May 2023 11:09:45 -0400 Received: by mail-ed1-x52a.google.com with SMTP id 4fb4d7f45d1cf-50bc5197d33so11341484a12.1 for ; Tue, 09 May 2023 08:09:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1683644980; x=1686236980; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=yuP6Nqn9mJTNOPU0Dnc8yj52myNrmRS59kymFA9fyP8=; b=TgFn7EeNyiRJ8CYMeZxGPt35djp+kfYNjaSIL4umBg4QlkEkKeYCweEmM3mDe7wDwP JtCMqeyw9eehlpOlVdTIm1PCN0aQqT7FYGyCbPiPVHpljFAjFdnjcQLe8bVr5rJJ9DtO GmR2GpmOTHGyTI4bo2AD5u2w2UkGX8a6Ma9B7vG5mQq/IUZmL+h8YXPWc/5m8XtqLMZQ m6zfTwhGh9zI/I2tGpt5l91KKyVa/P537ndY/2YdZeUtNvzf+rAS/ah05S76/VFwf3Of /3yr2MCv9qwvOi9dhtoa6MVX5G7fuwGbNbcHHALkG1trTsHMPGIEhWprwMYsbArEUkDK 4ISg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683644980; x=1686236980; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=yuP6Nqn9mJTNOPU0Dnc8yj52myNrmRS59kymFA9fyP8=; b=fZGBcBT/537qoCDphF8X7r60UnW2xCXNxSNOixkDmr9uiINuVlvb+uUolzC8E93mbc rsxRfZjYqct5BlVkI0oy/1uSvwA2fOWiuzXFM9tdLV0y0v7d6jAJWy9z2Oe46FwOa6Iu KyT60JUJzLmHKVhbs3L9iO3CYWCH30uzh9Hc3rfj5TQMQVvVBx4aO3g7lhXyBGzSXTyx yM1pmdVRQDk+AkYOcS9j4taUWE39t5K7Rc/Nyw/3+FTgiVQNxIax+YkPSfOL+C+twimM tC4SngcD8CVjTUVSplm17IphZPhQ755b417IDg2KysN9So5+bsL9KFikQ6YoNxxVBY9+ Pimg== X-Gm-Message-State: AC+VfDwKtKToltEraw5a9/51F559XAM+v3unatA8/Aa7BN73d3Jn/01z vfET1h+49rknv5vK2sK9gqBiHZkSCaq7ifWqxBLnZA== X-Google-Smtp-Source: ACHHUZ7C6epciNC4EGrHIOLw7c740yHULxj07iC3YZnNGcZvii53xDIgahUrlZ1av1UNuF8nq3sKtvA4Mv29iOV2C6E= X-Received: by 2002:aa7:c548:0:b0:50b:b7f5:3128 with SMTP id s8-20020aa7c548000000b0050bb7f53128mr10431201edr.12.1683644980086; Tue, 09 May 2023 08:09:40 -0700 (PDT) MIME-Version: 1.0 References: <20230509142639.253947-1-pbonzini@redhat.com> In-Reply-To: <20230509142639.253947-1-pbonzini@redhat.com> From: Peter Maydell Date: Tue, 9 May 2023 16:09:29 +0100 Message-ID: Subject: Re: [PATCH] target/i386: fix operand size for VCOMI/VUCOMI instructions To: Paolo Bonzini Cc: qemu-devel@nongnu.org, ricky@rzhou.org, Gabriele Svelto Content-Type: text/plain; charset="UTF-8" Received-SPF: pass client-ip=2a00:1450:4864:20::52a; envelope-from=peter.maydell@linaro.org; helo=mail-ed1-x52a.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, 9 May 2023 at 15:27, Paolo Bonzini wrote: > > Compared to other SSE instructions, VUCOMISx and VCOMISx are different: > the single and double precision versions are distinguished through a > prefix, however they use no-prefix and 0x66 for SS and SD respectively. > Scalar values usually are associated with 0xF2 and 0xF3. > > Because of these, they incorrectly perform a 128-bit memory load instead > of a 32- or 64-bit load. Fix this by writing a custom decoding function. > > I tested that the reproducer is fixed and the test-avx output does not > change. > > Reported-by: Gabriele Svelto > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1637 > Fixes: f8d19eec0d53 ("target/i386: reimplement 0x0f 0x28-0x2f, add AVX", 2022-10-18) > Signed-off-by: Paolo Bonzini Worth Cc: qemu-stable@nongnu.org also? We have real-world reports of guests falling over on this. thanks -- PMM