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 C51D01125863 for ; Wed, 11 Mar 2026 18:41:16 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1w0OUT-0007nI-T8; Wed, 11 Mar 2026 14:41:05 -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 1w0OUS-0007n8-6P for qemu-devel@nongnu.org; Wed, 11 Mar 2026 14:41:04 -0400 Received: from linux.microsoft.com ([13.77.154.182]) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1w0OUP-0002Hs-MO for qemu-devel@nongnu.org; Wed, 11 Mar 2026 14:41:03 -0400 Received: from example.com (unknown [167.220.208.53]) by linux.microsoft.com (Postfix) with ESMTPSA id B03EF20B710C; Wed, 11 Mar 2026 11:40:58 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com B03EF20B710C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1773254460; bh=Yea9CnSrVBxTpJJdJ1t+9tiil4FxoJfgMDXXvt6uYUE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=M66V7IKx5AsNn/9ENBHcFTXzeYDUOQ3o67ERJbgTowPOJbbaoQrEI2pgB+CSS4x6C 2diof0mUICYxlDvMZdZQfT/wqV3PV8z+sv2xa+l5pFOqJfVnk8bcLrFrFIOPX+/dNO AJ7Zx1DV2fTS3uLtTs+zmhddJIOHyZ8RwpUz8vds= Date: Wed, 11 Mar 2026 19:40:55 +0100 From: Magnus Kulke To: Mohamed Mediouni Cc: qemu-devel@nongnu.org, Zhao Liu , Paolo Bonzini , Wei Liu , Magnus Kulke , Wei Liu Subject: Re: [PATCH v2 9/9] accel/mshv: disable la57 (5lvl paging) Message-ID: References: <20260311113505.1177878-1-magnuskulke@linux.microsoft.com> <20260311113505.1177878-10-magnuskulke@linux.microsoft.com> <2D1F935F-865A-4B24-B616-BEE57B22FB2B@unpredictable.fr> <5FCD2D66-8079-4F65-A85D-473F78FBC1D4@unpredictable.fr> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <5FCD2D66-8079-4F65-A85D-473F78FBC1D4@unpredictable.fr> Received-SPF: pass client-ip=13.77.154.182; envelope-from=magnuskulke@linux.microsoft.com; helo=linux.microsoft.com X-Spam_score_int: -9 X-Spam_score: -1.0 X-Spam_bar: - X-Spam_report: (-1.0 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, Mar 11, 2026 at 04:31:41PM +0100, Mohamed Mediouni wrote: > Thank you, I’ll test this further. Boot-tested it on an Alpine Linux VM but looks like > that wasn’t enough... > > FYI I added a new callback interface in x86_emul_ops (mmu_gva_to_gpa) to support > adding the Hyper-V page table walker, but if it’s anything like the WHP one it’s going to > be very slow… which is why I moved to the new interface in the first place. hmm, I quickly tried that and implemented a hook like this: static MMUTranslateResult gva_to_gpa(CPUState *cpu, target_ulong gva, uint64_t *gpa, MMUTranslateFlags flags) { uint64_t hv_flags = 0; if (!x86_is_paging_mode(cpu)) { *gpa = gva; return MMU_TRANSLATE_SUCCESS; } if (flags & MMU_TRANSLATE_VALIDATE_WRITE) { hv_flags = HV_TRANSLATE_GVA_VALIDATE_WRITE; } else if (flags & MMU_TRANSLATE_VALIDATE_EXECUTE) { hv_flags = HV_TRANSLATE_GVA_VALIDATE_EXECUTE; } else { hv_flags = HV_TRANSLATE_GVA_VALIDATE_READ; } if (translate_gva(cpu, gva, gpa, hv_flags) < 0) { return MMU_TRANSLATE_PAGE_NOT_MAPPED; } return MMU_TRANSLATE_SUCCESS; } static const struct x86_emul_ops mshv_x86_emul_ops = { .read_segment_descriptor = read_segment_descriptor, .mmu_gva_to_gpa = gva_to_gpa, }; but without explicitly disabling la57, I still see the same MMIO errors during guest boot (ubuntu jammy). probably needs more investigation. I think for now disabling la57 seems ok.