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.gnu.org (lists.gnu.org [209.51.188.17]) (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 5CD611093163 for ; Fri, 20 Mar 2026 01:57:27 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1w3P6f-0005tf-78; Thu, 19 Mar 2026 21:56:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1w3P6e-0005tX-A1 for qemu-arm@nongnu.org; Thu, 19 Mar 2026 21:56:56 -0400 Received: from out-187.mta1.migadu.com ([95.215.58.187]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1w3P6c-0000pj-Na for qemu-arm@nongnu.org; Thu, 19 Mar 2026 21:56:56 -0400 Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1773971803; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AmvR/M3JI8dcsRutv6D6h9NwaJ2teAlvSiCFrM2lkk0=; b=dl8brKpC6x8ezz93/6sSalv7Hpqvq6hBSdQqnGwcNlWrBo3SEbaf7xFslOyjL5uNy97Pfw 3xF/llFBjTvAjRtEFTzGEJDmEroKE5arHWzlfvLGGtH8DPlXfZFwbWUvnie0IQOx08JXii eNmxsUDtarsTxZM0/qxXXLgdOxnL0X0= Date: Fri, 20 Mar 2026 09:56:27 +0800 MIME-Version: 1.0 Subject: Re: [PATCH] target/arm: Don't skip access flag fault for AccessType_AT To: Peter Maydell Cc: qemu-arm@nongnu.org, qemu-devel@nongnu.org, richard.henderson@linaro.org References: <20260317122517.47627-1-zenghui.yu@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Zenghui Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT Received-SPF: pass client-ip=95.215.58.187; envelope-from=zenghui.yu@linux.dev; helo=out-187.mta1.migadu.com X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.819, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.903, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-arm@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org Sender: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org Hi Peter, On 3/20/26 1:17 AM, Peter Maydell wrote: > On Tue, 17 Mar 2026 at 12:25, Zenghui Yu wrote: > > > > As per the pseudo code from DDI0487 M.a.a (on J1-16021) AArch64.S1Walk(): > > > > // Check descriptor AF bit > > elsif (descriptor<10> == '0' && walkparams.ha == '0' && > > (!accdesc.acctype IN {AccessType_DC, AccessType_IC} || > > boolean IMPLEMENTATION_DEFINED "Generate access flag fault on IC/DC operations")) then > > fault.statuscode = Fault_AccessFlag; > > > > an access flag fault should be generated for AccessType_AT, if the AF bit > > is 0 and !param.ha. > > Did you find this by code inspection, or because it caused > a guest to go wrong? This was noticed when I was fixing the AT selftest on KVM side [*]. [*] https://lore.kernel.org/r/d58819b9-c745-4551-8ea4-e15af3fe63be@linux.dev Thanks, Zenghui