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 0318125DAFF for ; Fri, 26 Sep 2025 08:47:17 +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=1758876438; cv=none; b=TfwDp1MRVfJWcTxYDqOqcpJbCUHt0aS6YsqGHLJKzTUZGGE1WBeOagzp2mAQ2oydMmGb1ohA1thGUjf3heCvfvcgkeIkU8u7S0/S8sZPd96WRVaCy/r+RjtwxqCBTLmVbXefCjFFHKX5luWDaXCJVqg2q0onpezi7E9nykBh+MM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758876438; c=relaxed/simple; bh=pC6Xo5HsxzIeC/HD0wRUR8XYy10SDXQ1jj7BmJ6w7nk=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=nwsLVI4kQq+ZYIQ8w1Q6rKwiUEEGU872iWUhf5YpyHLSn5oViusirQueoRns77pEgqSlr5qCW98SaJAVqABcvQ8iES6V7PUWPkpW2/b9HfK6Ue4O2qDcY8XlVioS4cMgY/GGL9skyl2+TgZDMboyq8O1eV40eU0101gaqGHaBuw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M+fnjX+W; 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="M+fnjX+W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8CC7AC4CEF4; Fri, 26 Sep 2025 08:47:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758876437; bh=pC6Xo5HsxzIeC/HD0wRUR8XYy10SDXQ1jj7BmJ6w7nk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=M+fnjX+WtJusxq7dtv1f5CK40ICoTBBlmKOj6JAUxOVlU4VT9WdkAA5Xl7C5joCbt qVWyFbGkOKoEV7zWSZDWG2eGxAxUVHd7DfPKjm3itIex6Wvan0ik4AqhbAj8wPoWsu uKnT1PcvfpA01ruUkkKIt7XGOBXtxVIUE1C4N5qJ9/eqC6AMKZpyHA8HBz5dt6FwF6 yXmVQ12wXE5eClacB4Kr6W726ueYJ+JSGtltOyvnR1DZlMoG708Q8px+scj8flEJ0N OTxmLT8UtelMLPMOaNH/SmhCaVFQPDlFwGaxdHYYsE4NDth8tbTZ+6875Bh8k1BG+Q DN4UAtBgFtSBQ== 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 4.98.2) (envelope-from ) id 1v246l-00000009bjQ-0TEW; Fri, 26 Sep 2025 08:47:15 +0000 Date: Fri, 26 Sep 2025 09:47:14 +0100 Message-ID: <8634891tyl.wl-maz@kernel.org> From: Marc Zyngier To: Nianyao Tang Cc: , , , , , , , Subject: Re: [PATCH V2] irqchip/gic-v4.1:Check whether indirect table is supported in allocate_vpe_l1_table In-Reply-To: <20250918141557.1791041-1-tangnianyao@huawei.com> References: <20250918141557.1791041-1-tangnianyao@huawei.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/30.1 (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: tangnianyao@huawei.com, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, guoyang2@huawei.com, wangwudi@hisilicon.com, wangzhou1@hisilicon.com, jiangkunkun@huawei.com, guozicheng3@hisilicon.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Thu, 18 Sep 2025 15:15:57 +0100, Nianyao Tang wrote: > > In allocate_vpe_l1_table, it allocates a new vpe table without checking > whether indirect table is supported. > ARM allows vendors to support only flat tables. Let's first check if > indirect tables are supported before using it. > > Signed-off-by: Nianyao Tang As I understand it, this is for the same machines that also requires [1] and [2] to be able to use vLPIs and vSGIs. I seriously doubt that we want *any* of it (creating userspace ABI to deal with a broken design is not something I'm keen on). Frankly, you should consider disabling GICv4.1 on these machines, and stick with GICv3 (which I assume works correctly). Thanks, M. [1] https://lore.kernel.org/r/20250825023954.3516381-1-wangzhou1@hisilicon.com [2] https://lore.kernel.org/r/20250909110615.129179-1-wangzhou1@hisilicon.com -- Without deviation from the norm, progress is not possible.