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 34D3B1A073C for ; Tue, 18 Jun 2024 08:15:40 +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=1718698541; cv=none; b=EsoMXuXypfa+uvEqLUtIymuGL7NoX7Qg1jOxWbwC8FEc60haFdfRKmx6dc8eJ2e1El9okjLyIcNxFmhWIEGPBk+NJCOSsufQBbKqFC0DN6oYTGXQ7FLyyL9X2hfCq3VLxFz/NCu+7q5ApsgUYVjmvSDlllgLPP5HS7R5X9hBJJI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718698541; c=relaxed/simple; bh=iYioEWORDDUMLHtKnujTc36m4+0j/4elywu9H2FX8UQ=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=HmMGQGeD8uNPKQ52KNzEgSBh58JV/OKVzS91xBZtuVjtmDOPorO2LjdEvn3hib3tqi2oxTmr/vB4XsX5UPIIIMFLhrE7jwDPkceDMpdOlckL3D11I4I3sg/OG3TS1Sdbn0yhv13q9XtDkiHg1cuDk3xKiPFtYw+J4ljb2IoGnkw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OMnw/u+p; 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="OMnw/u+p" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1E01C3277B; Tue, 18 Jun 2024 08:15:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718698540; bh=iYioEWORDDUMLHtKnujTc36m4+0j/4elywu9H2FX8UQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=OMnw/u+pJ6a9Sb30gXqTMC78NV+7Mdo/Q3XtkF3C8QAzLBPb6c8BveAHaLw2f1SR4 UMqEFyr9cvZVbObLQetIsi+5rNsvfXo1ruqiSz2IIPH+Wa34sBRpLkFkeJquZ+6jHP cOzKGttDTC/0pfURvv0KlVj9fqH+umGW7PaQadMDLMnX8p4v5UPr/EH1vLbYh2s4q4 HyAANnAJ5QCLIQHk5n2NRQS1XdGC7OrLLkWBzyWbUZTojDbMbiKBn0GXfqkuDIzkUL V5WdpCM8WJTWSAHtZjaRi9LEpGTsZnUUKjqSL3Cv7gV7EMEgXrcZkOi7gltII5YiT4 /GXoXw17gfK1A== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1sJU0A-004sL0-JB; Tue, 18 Jun 2024 09:15:38 +0100 Date: Tue, 18 Jun 2024 09:15:37 +0100 Message-ID: <86cyoek6om.wl-maz@kernel.org> From: Marc Zyngier To: Anshuman Khandual Cc: linux-arm-kernel@lists.infradead.org, mark.rutland@arm.com, ryan.roberts@arm.com, Catalin Marinas , Will Deacon , linux-kernel@vger.kernel.org Subject: Re: [PATCH V2] arm64/mm: Stop using ESR_ELx_FSC_TYPE during fault In-Reply-To: <20240618034703.3622510-1-anshuman.khandual@arm.com> References: <20240618034703.3622510-1-anshuman.khandual@arm.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/29.2 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: anshuman.khandual@arm.com, linux-arm-kernel@lists.infradead.org, mark.rutland@arm.com, ryan.roberts@arm.com, catalin.marinas@arm.com, will@kernel.org, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Tue, 18 Jun 2024 04:47:03 +0100, Anshuman Khandual wrote: > > Fault status codes at page table level 0, 1, 2 and 3 for access, permission > and translation faults are architecturally organized in a way, that masking > out ESR_ELx_FSC_TYPE, fetches Level 0 status code for the respective fault. > > Helpers like esr_fsc_is_[translation|permission|access_flag]_fault() mask > out ESR_ELx_FSC_TYPE before comparing against corresponding Level 0 status > code as the kernel does not yet care about the page table level, where in > the fault really occurred previously. > > This scheme is starting to crumble after FEAT_LPA2 when level -1 got added. > Fault status code for translation fault at level -1 is 0x2B which does not > follow ESR_ELx_FSC_TYPE, requiring esr_fsc_is_translation_fault() changes. > > This changes above helpers to compare against individual fault status code > values for each page table level and stop using ESR_ELx_FSC_TYPE, which is > losing its value as a common mask. > > Cc: Catalin Marinas > Cc: Will Deacon > Cc: Marc Zyngier > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Anshuman Khandual Reviewed-by: Marc Zyngier M. -- Without deviation from the norm, progress is not possible.