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=-7.5 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,HTML_MESSAGE,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 C6C23C433F5 for ; Wed, 15 Sep 2021 09:58:32 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 2F82960F26 for ; Wed, 15 Sep 2021 09:58:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 2F82960F26 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:55228 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mQRgV-00073p-57 for qemu-devel@archiver.kernel.org; Wed, 15 Sep 2021 05:58:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60842) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mQRfn-0006N6-Ke; Wed, 15 Sep 2021 05:57:47 -0400 Received: from mail-io1-xd36.google.com ([2607:f8b0:4864:20::d36]:43628) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1mQRfk-0008Pt-KX; Wed, 15 Sep 2021 05:57:47 -0400 Received: by mail-io1-xd36.google.com with SMTP id n24so2590935ion.10; Wed, 15 Sep 2021 02:57:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=7gqcGDXwA6e97UbMcLuLWlqD9l/Qn0L/bVAx+xa8t5Q=; b=mNLTlZbpQM+0GiSVJqpzf0vi35KNG3uOWJGeXwz8p0VtFe3Nk2tYwW/RigH+O3nSJf +unrBsE8Kh1A0WZIgP7HIcCDa0mWUuoKcN+qlKGEQ4UWV52hZx8nc0pzkHAWK42l436L uUyYqLNXnWw6KlxuXeABc7KLvSj5DvPiE0Q7FT25aXBMr0KyPyRLOnE2YCfABMnwkbGn yQ5bB4XOutcXsKVTyKcuS8+tmCBD610YGtThij9BnUxE93h3CoBnbZXUqjCxRNGuY8Up ktqobqIuZ2BN9GLEMOlXJGESF6L8Agwucp5+aeJ9kfALdqRHzzW6h7BOjfGlLczWhpR+ Sf+Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=7gqcGDXwA6e97UbMcLuLWlqD9l/Qn0L/bVAx+xa8t5Q=; b=6g2vTebP83iCwpwjlPNe28vYzQunMWLGFirXTzR/Fe34BJNeV5qIFyUDsIuJuswnOr JDGWnWEC5IKWjYRvJDS+cSLNK3NkCrAyka7MdAfuBerdGFTMjO3Egn4Jfxduqj5oC7l1 jCCMLv001BIyMIfcc1GkCVlr8m7I/D1vBkaeRYBNEfJ3TGBKvONYP8F1SbvhNvB9c1AI 2LkujFV0dQemrclvIt4ETUINpm6R1Hd7e2HZgAQdCzE5ThGo6nCBum8yxaQlpqmae5ir +HofMatRSwUb2BFUEuBIVNDRpYXCPWPprJVO+T9auv8zuxsmJQTpo7Vnw7x+SMeRVTEY A+Ww== X-Gm-Message-State: AOAM532npnAiDoL55D8UlvaADazcTG/epYxXrApytf7RHOR3LxnguRUQ rwQEptuCI/ZRXHKyJBsa6ZTohetYEp6KOqQ/O9CiYfk5 X-Google-Smtp-Source: ABdhPJzhvuLW+18UUeoRTBZl3NUrZGbI/aCv4cChi77MFLWXniciofH1aWuqqA34MFYzxLYHwwfqCsZRmF8wnVC3IvY= X-Received: by 2002:a6b:dc1a:: with SMTP id s26mr13887784ioc.191.1631699862696; Wed, 15 Sep 2021 02:57:42 -0700 (PDT) MIME-Version: 1.0 References: <20210914120725.24992-1-peter.maydell@linaro.org> In-Reply-To: <20210914120725.24992-1-peter.maydell@linaro.org> From: Christophe Lyon Date: Wed, 15 Sep 2021 11:57:31 +0200 Message-ID: Subject: Re: [PATCH 0/3] target/arm: Set FPSCR.LTPSIZE for user-mode To: Peter Maydell Content-Type: multipart/alternative; boundary="000000000000b236bc05cc05baf5" Received-SPF: pass client-ip=2607:f8b0:4864:20::d36; envelope-from=christophe.lyon.oss@gmail.com; helo=mail-io1-xd36.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, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Christophe Lyon , qemu-arm@nongnu.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --000000000000b236bc05cc05baf5 Content-Type: text/plain; charset="UTF-8" Hi Peter, Thanks for the prompt patches! On Tue, Sep 14, 2021 at 2:08 PM Peter Maydell wrote: > This patchset fixes https://gitlab.com/qemu-project/qemu/-/issues/613 > which is a bug where we weren't setting FPSCR.LTPSIZE correctly > out of reset for the user-mode emulator. The effect is that > when using an M-profile CPU with the low-overhead-branch or MVE > extensions (ie the Cortex-M55) with the linux-user QEMU the 'LE' > instruction would take a UserFault and MVE instructions would > be incorrectly predicated. > > This is the result of some over-exuberant ifdeffery in the > arm_cpu_reset() function. Patch 1 fixes that so that most of > the M-profile-specific reset handling is not ifdeffed, and > when we're in user mode we specifically set the FPU state up > cleanly. Patches 2 and 3 are just follow-on tidyup. > > Christophe, if you are in a position to test this series with: > M55 (has Security, MVE and LOB) > M33 (has Security extension but not MVE/LOB) > M7 or M4 (no Security, but does have FPU) > that would be ideal. I don't really have much in the way of > test cases for usermode to hand, so it's possible that I > forgot something in the init of the FPU state that might break > one of those combinations. (It does fix the test case attached > to the bug report.) > I ran the GCC testsuite with these configurations, and found no regression compared to qemu-6.0, thanks. In the M55 case, this also enabled many more tests, which is great! Christophe > thanks > -- PMM > > Peter Maydell (3): > target/arm: Don't skip M-profile reset entirely in user mode > target/arm: Always clear exclusive monitor on reset > target/arm: Consolidate ifdef blocks in reset > > target/arm/cpu.c | 39 ++++++++++++++++++++++++++++----------- > 1 file changed, 28 insertions(+), 11 deletions(-) > > -- > 2.20.1 > > > --000000000000b236bc05cc05baf5 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Peter,

Thanks for the pro= mpt patches!

On Tue, Sep 14, 2021 at 2:08 PM Peter Maydell <peter.maydell@linaro.org> wrote:
<= /div>
This patchset fixes = https://gitlab.com/qemu-project/qemu/-/issues/613
which is a bug where we weren't setting FPSCR.LTPSIZE correctly
out of reset for the user-mode emulator. The effect is that
when using an M-profile CPU with the low-overhead-branch or MVE
extensions (ie the Cortex-M55) with the linux-user QEMU the 'LE' instruction would take a UserFault and MVE instructions would
be incorrectly predicated.

This is the result of some over-exuberant ifdeffery in the
arm_cpu_reset() function. Patch 1 fixes that so that most of
the M-profile-specific reset handling is not ifdeffed, and
when we're in user mode we specifically set the FPU state up
cleanly. Patches 2 and 3 are just follow-on tidyup.

Christophe, if you are in a position to test this series with:
=C2=A0M55 (has Security, MVE and LOB)
=C2=A0M33 (has Security extension but not MVE/LOB)
=C2=A0M7 or M4 (no Security, but does have FPU)
that would be ideal. I don't really have much in the way of
test cases for usermode to hand, so it's possible that I
forgot something in the init of the FPU state that might break
one of those combinations. (It does fix the test case attached
to the bug report.)




thanks
-- PMM

Peter Maydell (3):
=C2=A0 target/arm: Don't skip M-profile reset entirely in user mode
=C2=A0 target/arm: Always clear exclusive monitor on reset
=C2=A0 target/arm: Consolidate ifdef blocks in reset

=C2=A0target/arm/cpu.c | 39 ++++++++++++++++++++++++++++-----------
=C2=A01 file changed, 28 insertions(+), 11 deletions(-)

--
2.20.1


--000000000000b236bc05cc05baf5--