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[31.30.173.16]) by smtp.gmail.com with ESMTPSA id c25-20020a50f619000000b004bd6e3ed196sm7761962edn.86.2023.03.22.05.46.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Mar 2023 05:46:32 -0700 (PDT) Date: Wed, 22 Mar 2023 13:46:31 +0100 From: Andrew Jones To: "Jason A. Donenfeld" Cc: Jisheng Zhang , Palmer Dabbelt , Paul Walmsley , Albert Ou , Anup Patel , Atish Patra , Heiko Stuebner , Conor Dooley , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, regressions@leemhuis.info, regressions@lists.linux.dev Subject: Re: [PATCH] riscv: require alternatives framework when selecting FPU support Message-ID: <20230322124631.7p67thzeblrawsqj@orel> References: <20230322120907.2968494-1-Jason@zx2c4.com> Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230322120907.2968494-1-Jason@zx2c4.com> On Wed, Mar 22, 2023 at 01:09:07PM +0100, Jason A. Donenfeld wrote: > When moving switch_to's has_fpu() over to using riscv_has_extension_ > likely() rather than static branchs, the FPU code gained a dependency on > the alternatives framework. If CONFIG_RISCV_ALTERNATIVE isn't selected > when CONFIG_FPU is, then has_fpu() returns false, and switch_to does not > work as intended. So select CONFIG_RISCV_ALTERNATIVE when CONFIG_FPU is > selected. > > Fixes: 702e64550b12 ("riscv: fpu: switch has_fpu() to riscv_has_extension_likely()") > Link: https://lore.kernel.org/all/ZBruFRwt3rUVngPu@zx2c4.com/ > Cc: Jisheng Zhang > Cc: Andrew Jones > Cc: Heiko Stuebner > Cc: Conor Dooley > Signed-off-by: Jason A. Donenfeld > --- > arch/riscv/Kconfig | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index c5e42cc37604..0f59350c699d 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -467,6 +467,7 @@ config TOOLCHAIN_HAS_ZIHINTPAUSE > config FPU > bool "FPU support" > default y > + select RISCV_ALTERNATIVE > help > Say N here if you want to disable all floating-point related procedure > in the kernel. > -- > 2.40.0 > Reviewed-by: Andrew Jones I took a look to see if we missed anything else and see that we should do the same patch for KVM. I'll send one. (It's tempting to just select RISCV_ALTERNATIVE from RISCV, but maybe we can defer that wedding a bit longer.) Thanks, drew 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 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 80D58C6FD1F for ; Wed, 22 Mar 2023 12:46:55 +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:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=6etKk/JU54lYa/fRHPD2bnpNnO5T970N7a+yoo+NU1Q=; b=ZHCQWDwdSMxBTS gZhIq7+DFmAoJSJr2AYm7M7/TrZzfoYkMzsof7DjnRfYxWZ8c1v5OwhofqtFldURyl1KniJSHMfSh Q6kEIjdlLlKmnZ7C9KZvNwhd8qZKFLokhkNnnPnKYcSCEKi8er37QrQQHChyMg+erXTGj4mc5SzfW rVS27YbbIHMybssS4/ehJvWPyULJudz9GBg6ZdSK3OMptPuVEV8dV7eNt+jdpoOsarCvBZfwzHGtK xi8m10dCnM7tEc8NEUMAOXaIIruRTpgyb9bKjNvkWkpx5HHihznMXWGS9LtuhezcXuAord7KqyOto lCxnQverwDnUQtrQF4yw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pexrZ-00Fzao-1L; Wed, 22 Mar 2023 12:46:45 +0000 Received: from mail-ed1-x52a.google.com ([2a00:1450:4864:20::52a]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pexrT-00FzWi-2M for linux-riscv@lists.infradead.org; Wed, 22 Mar 2023 12:46:42 +0000 Received: by mail-ed1-x52a.google.com with SMTP id eg48so72312491edb.13 for ; Wed, 22 Mar 2023 05:46:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ventanamicro.com; s=google; t=1679489195; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=W5zKbHjfhgxF54RZN2uMVwaO/XV5lTFGogMg3VcS9Gw=; b=g0bBuwgqfq8NKbwhZFZrgh3ILJQ25NRW5qmNmABpR/5J7UMpNHAgm8YKjMO2Sam/b1 MTvpDdEagorVMuehmgxKrl4YStGgrnAooCP+TADfp7Gms6SGocetTcammGQPbuNERIxm OkR0IkAiwTXDztGkkP9JhEUx8qtCRNfLOA1zuX84EvQirnpJKEMR9BaDiPdWHtWwh9g1 ePEOpsQs8gcvuHGwZTBats0t6ZaUhAe6MaPKGUXknAROm4VvIa4KS9t3ODGfGMp7ZUK3 3WimQkNd1WdmFoQ8wRpIQKMvYjQnCDsJjqynML4PMoDU8iYKKLYX78DF7ObFk08gSpZK Yhwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679489195; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=W5zKbHjfhgxF54RZN2uMVwaO/XV5lTFGogMg3VcS9Gw=; b=0oBqPSEt585vVLgLv4sR+FEc23m+w6p2mfk6LVVEOTiOjacmkQ7mT5nNE+tsUdf33/ x1E+Q4y4LB4VZ3j560obbCt7UxHY2gssAgsGLWKNvyqq8eStNsbfbpy1TpFA2NjbFy1N 5IOKF2D9k2Cvc2rArmHQS/alDo54ZBHBmgj0cbiNAuE69BulDFA07RxfXerqjOOqHKHO fEAEADdzPzWYBRHlsdIfBNeIYaubG6dF2BJ9ADvyQNJ52p2Kd5rMncXmmiTL36x1AXTR ADptR42yL8286RqT8omDvaD68WmtS7MTEDQdS5OroQOXUDLK0ag01tDXfsCv2mngCEob KSMg== X-Gm-Message-State: AO0yUKVOz5qg5xXbXzcpBYNvDkzJ9Grhz9B800/xK8XHsaXWXyKBpPTq kzvmVMiMmxVjZnLjQcBDOPxE0Q== X-Google-Smtp-Source: AK7set+gJyx2poiD3sfTmwA9axJroFF1RhsQFBXaCqd0DtnPZi3yDlC8QBiTKtp9e6oeJC2EllLOww== X-Received: by 2002:a05:6402:48c:b0:4fa:ad62:b1a0 with SMTP id k12-20020a056402048c00b004faad62b1a0mr5882545edv.41.1679489193201; Wed, 22 Mar 2023 05:46:33 -0700 (PDT) Received: from localhost (cst2-173-16.cust.vodafone.cz. [31.30.173.16]) by smtp.gmail.com with ESMTPSA id c25-20020a50f619000000b004bd6e3ed196sm7761962edn.86.2023.03.22.05.46.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Mar 2023 05:46:32 -0700 (PDT) Date: Wed, 22 Mar 2023 13:46:31 +0100 From: Andrew Jones To: "Jason A. Donenfeld" Cc: Jisheng Zhang , Palmer Dabbelt , Paul Walmsley , Albert Ou , Anup Patel , Atish Patra , Heiko Stuebner , Conor Dooley , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, regressions@leemhuis.info, regressions@lists.linux.dev Subject: Re: [PATCH] riscv: require alternatives framework when selecting FPU support Message-ID: <20230322124631.7p67thzeblrawsqj@orel> References: <20230322120907.2968494-1-Jason@zx2c4.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230322120907.2968494-1-Jason@zx2c4.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230322_054639_796996_C633ABF4 X-CRM114-Status: GOOD ( 17.66 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Wed, Mar 22, 2023 at 01:09:07PM +0100, Jason A. Donenfeld wrote: > When moving switch_to's has_fpu() over to using riscv_has_extension_ > likely() rather than static branchs, the FPU code gained a dependency on > the alternatives framework. If CONFIG_RISCV_ALTERNATIVE isn't selected > when CONFIG_FPU is, then has_fpu() returns false, and switch_to does not > work as intended. So select CONFIG_RISCV_ALTERNATIVE when CONFIG_FPU is > selected. > > Fixes: 702e64550b12 ("riscv: fpu: switch has_fpu() to riscv_has_extension_likely()") > Link: https://lore.kernel.org/all/ZBruFRwt3rUVngPu@zx2c4.com/ > Cc: Jisheng Zhang > Cc: Andrew Jones > Cc: Heiko Stuebner > Cc: Conor Dooley > Signed-off-by: Jason A. Donenfeld > --- > arch/riscv/Kconfig | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index c5e42cc37604..0f59350c699d 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -467,6 +467,7 @@ config TOOLCHAIN_HAS_ZIHINTPAUSE > config FPU > bool "FPU support" > default y > + select RISCV_ALTERNATIVE > help > Say N here if you want to disable all floating-point related procedure > in the kernel. > -- > 2.40.0 > Reviewed-by: Andrew Jones I took a look to see if we missed anything else and see that we should do the same patch for KVM. I'll send one. (It's tempting to just select RISCV_ALTERNATIVE from RISCV, but maybe we can defer that wedding a bit longer.) Thanks, drew _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv