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.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 45E5DF94CDF for ; Wed, 22 Apr 2026 08:07:10 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4g0sJX6dQ7z2yqs; Wed, 22 Apr 2026 18:07:08 +1000 (AEST) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip="2a00:1450:4864:20::630" ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1776845228; cv=none; b=UkNSvwRntuz/WeI7moqMpn3tY/jPsZw5FE/MTAp3Ck90JUjpiwAmIGn4N0leJATU3QoHYJSsksmsfzbMSzONMfE3kn/q2Dw4Yb59LTVyURBI7TDq1+gk1IxsOZuIzEYrIkkD7421zfV8U1PQMK1mSlGXvM5XUHT+8HuCTzCiUWGHoRZPUi0iLXjZhDv+cddsQjmLPBDqnY6b2KuTewKHv/U2z875yJltAlKZGXs3yPwyHn3EXBGOb7kbsbSo3pWCmCy52R8R9ozEoTr76p3Qs6zP96767Ua59KsZQT13uX3grCbXo448oAHHzwWK4no71id1qfaR50yCWM5ExafXzw== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1776845228; c=relaxed/relaxed; bh=+xnVaF+973Zb7xN4UvEz+8ZuM5TVrO0nSR9bASc5gWw=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=FIG6f3sZIO4lNhgu7z+7PM5gwoWOikH4SoFtdyGJbsU50pF+eRguIk2vpLqoYSt11msTCSPqRyjPXPP9qPQ2eqo4hJtNe11wegX0M2XhAZNOzrEVr2a8A3F27DG7SvtV1N88DiwWRe+a7VvEyBRbc9Ti4SIBxmjAjxG4t373orjMrXIAKH9HS77WbxxZ6BImZBnWNmG92XUsCiULqwOWowkmYPKt51e230ovBXRCYTgAJd/94NHyt3Q94A00DWuyqOaJ4ZvupvI4KYYXKEEvNv055dAdx02ZMsEJ3MqtwU/H1j0Js61kOUoCGspVhInWHnRvQqFKXYeSaSFQYvlCeQ== ARC-Authentication-Results: i=1; lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=chromium.org; dkim=pass (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.a=rsa-sha256 header.s=google header.b=ICgTSCxi; dkim-atps=neutral; spf=pass (client-ip=2a00:1450:4864:20::630; helo=mail-ej1-x630.google.com; envelope-from=ribalda@chromium.org; receiver=lists.ozlabs.org) smtp.mailfrom=chromium.org Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.a=rsa-sha256 header.s=google header.b=ICgTSCxi; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=chromium.org (client-ip=2a00:1450:4864:20::630; helo=mail-ej1-x630.google.com; envelope-from=ribalda@chromium.org; receiver=lists.ozlabs.org) Received: from mail-ej1-x630.google.com (mail-ej1-x630.google.com [IPv6:2a00:1450:4864:20::630]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4g0sJW0NK3z2yql for ; Wed, 22 Apr 2026 18:07:06 +1000 (AEST) Received: by mail-ej1-x630.google.com with SMTP id a640c23a62f3a-ba36357195bso604812766b.0 for ; Wed, 22 Apr 2026 01:07:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1776845221; x=1777450021; darn=lists.ozlabs.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=+xnVaF+973Zb7xN4UvEz+8ZuM5TVrO0nSR9bASc5gWw=; b=ICgTSCxicEZKAgx/8OL/2KPC/yck9LOZVNQQqL5LgsECCYm2vmq1cH+UWND4Y3yNng 6SSABnDb3ItL4omMgTaF35fKvS2J5x4Gtncgp63Zx4LMUB+a34Rd5/wfcnk1XNhsKrSq NSJtWFf9LIJd939sFbSnoOFbvJGE7qhFwH0Wg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776845221; x=1777450021; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=+xnVaF+973Zb7xN4UvEz+8ZuM5TVrO0nSR9bASc5gWw=; b=VY6fBZl3GaaDguae47w7v04iEreYmwmWocXf9S0hYMCBV+znJg1LwN+mIgAP5tYfBp OX5Cv1iaeDSrBxy/qfjBbcJiAIiwWnppw7prUIoa/jsJTpRMECZGDXLWac0fdyiUZCG5 5jdEu5/CosST9hsd3JnNxAZMxI8a8Pu1qFQarXLG8huqrgi/Pkm7W01GW530XG07uhbE l++NrNgDeEFGlHMvCWrIh+f/J5L+OfnteAiSk1RsIZYOwf5XgXUn/5YOI1kC/essAL+R eKyTo9wWAMexwPUi0vFxul6ESyIDcHP9GFGZ1yxNk9lemyS1hmxlJIUq2fdFE3Lq87l+ nQ5g== X-Forwarded-Encrypted: i=1; AFNElJ/Bi+OzTiGE7vB/6t2O8XaJiw4wyp7AmrxnFD1iTi4hPFiwJabTQuCjlpp0Ejlt8g2WXHskhG3SnCxMZDI=@lists.ozlabs.org X-Gm-Message-State: AOJu0YyX8o4kqjgXpfegF69xhLg34we09gxs4anfvjmQ1P42dWpgcM5k pQ7guZ9Ww0jlen74+11i5JTnPRII6FQhDf7Ot8wePr97jXMb+zfMOnzC6jI9LXpUfEYGCfpRcz3 25l8EJA== X-Gm-Gg: AeBDies3XUiYj7uyEHAiyI+XFqcxgYbMomCNSNFa1DG8XCNrsZ3RD0xLxVhb5M1SIst UNO+PV/wg6JWHDIM0SEbXso87bktYy3qNtebPONAmwDRv8Rph++mZ6gjf1lZTPtbGyEQrSDasRT ZjzHJVFEIO0+77zxS+k3LTlVDJBGphthovEVCrG/tCpaX++uGVTVpgYKfqC4aXM3fqj3fXzSdIF 7kB1PmU+wAjR8YtP1CymQLjaL9TYY0CFjwpGpQ1kN0yESpn1K8DgOLMY89tPH5CW1tvsUiLczEq zXVBsgLtK8Izb10BBTfOP3+qlyjZcvYCyN5nFN9IOj7f7ojrhVRiaZWIJ4S7axyzvMx7AYPfg8t XbInktaI+CJdjZM6rCHvBD7agDzy/CYSmyqYgDDa6iotT5+3DA02cgV1BU6YI/+V0k0Thk2witV wLL9tRgDirepgn004gk2u/7nU/5mwR4TKcQaZR3VEPT4992U6tJAgzDbAm+DElHuktVyp+KCc= X-Received: by 2002:a17:907:806:b0:b9b:4519:7914 with SMTP id a640c23a62f3a-ba41a82618emr1078507066b.33.1776845221125; Wed, 22 Apr 2026 01:07:01 -0700 (PDT) Received: from mail-ej1-f46.google.com (mail-ej1-f46.google.com. [209.85.218.46]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-ba6366452c6sm379524666b.11.2026.04.22.01.07.00 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 22 Apr 2026 01:07:00 -0700 (PDT) Received: by mail-ej1-f46.google.com with SMTP id a640c23a62f3a-b9d9971d059so758799866b.2 for ; Wed, 22 Apr 2026 01:07:00 -0700 (PDT) X-Forwarded-Encrypted: i=1; AFNElJ9/8km1g50M1DGmnV4ipmUjODuWiFL96C/DIytsTZMza1gO8+gkMcad8T+gy7qbpUByt0Xy6CjgHZjNcJc=@lists.ozlabs.org X-Received: by 2002:a17:906:4fc5:b0:b9b:ddb2:b1c1 with SMTP id a640c23a62f3a-ba418f7f625mr936456766b.21.1776845219289; Wed, 22 Apr 2026 01:06:59 -0700 (PDT) X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 References: <20260422071541-9a295128-d913-418f-a21c-1386fca30290@linutronix.de> <20260422092713-4021a1a5-3a54-4260-878a-aec1bef3f8c7@linutronix.de> In-Reply-To: <20260422092713-4021a1a5-3a54-4260-878a-aec1bef3f8c7@linutronix.de> From: Ricardo Ribalda Date: Wed, 22 Apr 2026 16:06:45 +0800 X-Gmail-Original-Message-ID: X-Gm-Features: AQROBzA7vfrwO2plpLpwVGaJQHR2MKiQUcm7cyVmWYAcKsQQIyoUjhDJYfCBMLg Message-ID: Subject: Re: New warning in linus/master To: =?UTF-8?Q?Thomas_Wei=C3=9Fschuh?= Cc: linux-arm-kernel@lists.infradead.org, Linux Kernel Mailing List , linuxppc-dev@lists.ozlabs.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Thomas On Wed, 22 Apr 2026 at 15:32, Thomas Wei=C3=9Fschuh wrote: > > On Wed, Apr 22, 2026 at 03:00:11PM +0800, Ricardo Ribalda wrote: > > On Wed, 22 Apr 2026 at 13:57, Thomas Wei=C3=9Fschuh > > wrote: > > > On Wed, Apr 22, 2026 at 11:51:45AM +0800, Ricardo Ribalda wrote: > > > > Media-CI has found a couple of new warnings in the latest kernel > > > > version for aarch64 and powerpc. They get fixed with this patch and > > > > before moving I wanted to know if this was under your radar. > > > > > > Thanks for the report. I was not aware of these so far. > > > > > > > diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vd= so/Makefile > > > > index 7dec05dd33b7..65914842fae0 100644 > > > > --- a/arch/arm64/kernel/vdso/Makefile > > > > +++ b/arch/arm64/kernel/vdso/Makefile > > > > @@ -50,7 +50,7 @@ CFLAGS_vgettimeofday.o =3D $(CC_FLAGS_ADD_VDSO) > > > > CFLAGS_vgetrandom.o =3D $(CC_FLAGS_ADD_VDSO) > > > > > > > > ifneq ($(c-gettimeofday-y),) > > > > - CFLAGS_vgettimeofday.o +=3D -include $(c-gettimeofday-y) > > > > + CFLAGS_vgettimeofday.o +=3D -include $(c-gettimeofday-y) > > > > -Wno-maybe-uninitialized > > > > endif > > > > > > (...) > > > > > > I'd like to know exactly what is going on before suppressing the warn= ing. > > > It is a non-standard warning, only enabled by *some* of the vDSO buil= ds > > > for some reason. > > > > > > > https://gitlab.freedesktop.org/linux-media/users/ribalda/-/pipeline= s/1649144/test_report?job_name=3Dcross-gcc > > > > > > While I was able to download a configuration from this job and also u= se the > > > same container image, I can not reproduce the issue. Is the configura= tion the > > > full one or only the template? > > > > > > Could you provide full reproduction steps? > > > > You can try repro with: > > > > work/linux $ podman run -v .:/workdir/ --rm -it > > registry.freedesktop.org/linux-media/media-ci/build:latest > > $ cd /workdir > > $ CROSS_COMPILE=3Daarch64-linux-gnu- ARCH=3Darm64 make allyesconfig > > $ CROSS_COMPILE=3Daarch64-linux-gnu- ARCH=3Darm64 make > > arch/arm64/kernel/vdso/vgettimeofday.o > > > > The gcc version discrepancy is because I the error was due to old gcc > > version and I was playing around with that... but it fails in both > > gcc14 and gcc15 > > Ack. > > > You can try with debian testing with > > work/linux$ podman run -v .:/workdir/ --rm -it debian:testing > > $ apt-get update > > $ apt-get install gcc-aarch64-linux-gnu build-essential flex bison libs= sl-dev bc > > $ cd /workdir > > $ CROSS_COMPILE=3Daarch64-linux-gnu- ARCH=3Darm64 make allyesconfig > > $ CROSS_COMPILE=3Daarch64-linux-gnu- ARCH=3Darm64 make > > arch/arm64/kernel/vdso/vgettimeofday.o > > Both reproducers do *not* reproduce the issue for me. > (It is more or less exactly what I tried before) Ok, I think I found what is going on. media-ci was forcing KCFLAGS=3D-Wmaybe-uninitialized https://gitlab.freedesktop.org/linux-media/media-ci/-/blob/main/test-build.= sh?ref_type=3Dheads#L29 And something has changed in the kernel in the last version that triggers a (hopefully) false positive. can you try with: CROSS_COMPILE=3Daarch64-linux-gnu- ARCH=3Darm64 make KCFLAGS=3D-Wmaybe-uninitialized allyesconfig CROSS_COMPILE=3Daarch64-linux-gnu- ARCH=3Darm64 make KCFLAGS=3D-Wmaybe-uninitialized prepare ? > > Please note that this line does not work in general: > $ CROSS_COMPILE=3Daarch64-linux-gnu- ARCH=3Darm64 make arch/arm64/kernel/= vdso/vgettimeofday.o > > The vDSO object files can not be built in this way like regular kernel ob= ject > files and will produce a compiler error, but not the one under discussion= . > Instead the vDSO on arm64 is built during the 'make prepare' phase. > (Other architectures work differently, of course...) > > (...) > > > Thomas --=20 Ricardo Ribalda