From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4E3742ED848; Sun, 17 May 2026 06:56:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779000988; cv=none; b=QdOkTT7lnjg/SGNecvQXOF8zn9XQttr/rd4WVOtST/0W+/cus6jI0TLYgZSXL2MFmJbk7VOS1isnGhBUIT9IhaViZ7ib68WhxhOI288eQ862MsGEigslVhk9bxm0Zp07E5LOuuFWHh+cWWoMZ17j6FCjqwCPvL79KvtW71srDx8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779000988; c=relaxed/simple; bh=WfJI8//0rNc8Gw4ik+Cx70cFrQE8E/tdr3m42LSQEVg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uLTJmjZFCSd91LomljgHzFVVq4NrF8Kr/d31zjWPZup5HgicxR3zKHLleHwg5vklW0p4T3LVyz4fKzywwcAbOlQkoCojGxlnuRQioqeCu13zCFLp9oWiNxcA/OnS2iF+nu+n+iBXpUepACokWleo0pGdBRW1QhYgCr6G/CO1cMk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gJRNQK/o; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gJRNQK/o" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B9B4DC2BCB0; Sun, 17 May 2026 06:56:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779000987; bh=WfJI8//0rNc8Gw4ik+Cx70cFrQE8E/tdr3m42LSQEVg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gJRNQK/oQM8kuyyNA4wjJHym5YtDnZVlBwMOJyxzo8aM+fFZojqbCm/sHxzKbdYRh qcBaa4t7pshXyYaAdUJLWt7yiPWaK4qbb5b32PRpQFjm6zY1kYMN53mf2Ch4irsbWq J5NhJWN99E9piS/PziKuUJMwAWsl36pJ3bJdWezBf/hQrUcNPj836Z/rSYIltA0NTR d+K1QCW04pAMjTXfAybV0udAhC1wL9MHUJVSpdfkrQV2QGPTcRP23GEk9kcd7Wt3im Ro3Ar4duQrLvB4uO6wN5i4vVsEgikrveNInZ0mUAIGXvu4asFOcBLJXN9WiA70zvxt 6JTTj+f6tfE1w== Date: Sat, 16 May 2026 23:56:26 -0700 From: Drew Fustini To: sashiko@lists.linux.dev Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC v4 18/18] riscv: enable resctrl filesystem for Ssqosid Message-ID: References: <20260510-ssqosid-cbqri-rqsc-v7-0-v4-18-eb53831ef683@kernel.org> <20260512225649.4A949C2BCB0@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260512225649.4A949C2BCB0@smtp.kernel.org> On Tue, May 12, 2026 at 10:56:48PM +0000, sashiko-bot@kernel.org wrote: > This commit updates the RISCV_ISA_SSQOSID Kconfig option to select > RISCV_CBQRI_DRIVER. It conditionally selects the driver only if > RESCTRL_FS is enabled, aiming to keep the filesystem as a user choice. > > > RISCV_ISA_SSQOSID selects RISCV_CBQRI_DRIVER, which in turn depends > > on RESCTRL_FS. Enabling the resctrl filesystem itself stays a user > > Is this description accurate? > > The driver configuration shows that RISCV_CBQRI_DRIVER only depends on > RISCV && RISCV_ISA_SSQOSID. The filesystem integration is decoupled into > a separate silent config, so the driver does not actually depend on > the filesystem. The commit message is wrong. I will rewrite it to describe the actual wiring. > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > --- a/arch/riscv/Kconfig > > +++ b/arch/riscv/Kconfig > > @@ -596,6 +596,7 @@ config RISCV_ISA_SSQOSID > > depends on 64BIT > > default n > > select ARCH_HAS_CPU_RESCTRL > > + select RISCV_CBQRI_DRIVER if RESCTRL_FS > > Could this conditional selection lead to unexpected configurations? > > Because the driver does not actually depend on the filesystem, if a user > enables the SSQOSID extension but leaves RESCTRL_FS disabled, the > underlying hardware driver will unexpectedly not be automatically > selected. > > This differs from platforms like ARM64, where ARM64_MPAM unconditionally > selects ARM64_MPAM_DRIVER regardless of the filesystem configuration. The 'if RESCTRL_FS' guard is wrong. I will drop it so that enabling SSQOSID always pulls in the controller driver. -Drew