{"id":2222755,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2222755/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260413152326.63738-4-mohamed@unpredictable.fr/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260413152326.63738-4-mohamed@unpredictable.fr>","date":"2026-04-13T15:23:15","name":"[v10,03/14] whpx: i386: disable TbFlushHypercalls for emulated LAPIC","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"c8bc98883e288377ddb601331c7229a335473143","submitter":{"id":91318,"url":"http://patchwork.ozlabs.org/api/1.1/people/91318/?format=json","name":"Mohamed Mediouni","email":"mohamed@unpredictable.fr"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260413152326.63738-4-mohamed@unpredictable.fr/mbox/","series":[{"id":499721,"url":"http://patchwork.ozlabs.org/api/1.1/series/499721/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=499721","date":"2026-04-13T15:23:12","name":"whpx: i386: bug fixes, feature probing and CPUID","version":10,"mbox":"http://patchwork.ozlabs.org/series/499721/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2222755/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2222755/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=unpredictable.fr header.i=@unpredictable.fr\n header.a=rsa-sha256 header.s=sig1 header.b=eu3PIITC;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; helo=lists1p.gnu.org;\n envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n receiver=patchwork.ozlabs.org)"],"Received":["from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17])\n\t(using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4fvWRm5L49z1y2d\n\tfor ; Tue, 14 Apr 2026 01:24:52 +1000 (AEST)","from localhost ([::1] helo=lists1p.gnu.org)\n\tby lists1p.gnu.org with esmtp (Exim 4.90_1)\n\t(envelope-from )\n\tid 1wCJ8v-0005lB-De; Mon, 13 Apr 2026 11:24:05 -0400","from eggs.gnu.org ([2001:470:142:3::10])\n by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)\n (Exim 4.90_1) (envelope-from )\n id 1wCJ8V-0005UH-Ph\n for qemu-devel@nongnu.org; Mon, 13 Apr 2026 11:23:39 -0400","from qs-2007b-snip4-8.eps.apple.com ([57.103.84.149]\n helo=outbound.qs.icloud.com)\n by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)\n (Exim 4.90_1) (envelope-from )\n id 1wCJ8T-0000SK-TM\n for qemu-devel@nongnu.org; Mon, 13 Apr 2026 11:23:39 -0400","from outbound.qs.icloud.com (unknown [127.0.0.2])\n by p00-icloudmta-asmtp-us-east-2d-100-percent-10 (Postfix) with ESMTPS id\n 3A5161800175; Mon, 13 Apr 2026 15:23:35 +0000 (UTC)","from localhost.localdomain (unknown [17.57.155.37])\n by p00-icloudmta-asmtp-us-east-2d-100-percent-10 (Postfix) with ESMTPSA id\n 6F2911800133; Mon, 13 Apr 2026 15:23:33 +0000 (UTC)"],"Dkim-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=unpredictable.fr;\n s=sig1; t=1776093816; x=1778685816;\n bh=LeCfULzXVq8eMeXoD4HoazACVFGuCL5m06fQgObX99k=;\n h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme;\n b=eu3PIITCJ8Aj+sL9zzy1o53n8+wpTCslH5lrKtkWYsYCwnBFYx6cRPpEvGxkM3cp8C1Ctn6nSHBouDINL4XK8T3saqsg3MMatW5MNtjvSzH+mXYDjox/NeubeyrRmsnDEE1gGAqVAcuW9GRSvAGFYJWOwwkcIEHQQiiMGgNEzfD/Xb3SvGWIU9ENyAzxX+9UO3fs7JF0S/GgJI/HS06Cmi7N2GQsNFbNzCm2nNUZFcUxsmg7GuyvK4KvulD0UoCxsoiBWyRc8uJpBJ6/yUZzE92mHyc6pmWY1IiPgDIr6f2IVI+GYK8FEMcPGvalA5FnqUc/o8cWMzX4xGpJ0u3mPA==","mail-alias-created-date":"1752046281608","From":"Mohamed Mediouni ","To":"qemu-devel@nongnu.org","Cc":"Zhao Liu , \"Michael S. Tsirkin\" ,\n Paolo Bonzini , Wei Liu ,\n Roman Bolshakov ,\n Pedro Barbuda ,\n Mohamed Mediouni ,\n Phil Dennis-Jordan ","Subject":"[PATCH v10 03/14] whpx: i386: disable TbFlushHypercalls for emulated\n LAPIC","Date":"Mon, 13 Apr 2026 17:23:15 +0200","Message-ID":"<20260413152326.63738-4-mohamed@unpredictable.fr>","X-Mailer":"git-send-email 2.50.1","In-Reply-To":"<20260413152326.63738-1-mohamed@unpredictable.fr>","References":"<20260413152326.63738-1-mohamed@unpredictable.fr>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Proofpoint-ORIG-GUID":"_9IVXNzXR01xtAewPb6oyFeBy0jF_rhC","X-Authority-Info-Out":"v=2.4 cv=QsdTHFyd c=1 sm=1 tr=0 ts=69dd0a78\n cx=c_apl:c_pps:t_out a=bsP7O+dXZ5uKcj+dsLqiMw==:117\n a=bsP7O+dXZ5uKcj+dsLqiMw==:17 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22\n a=Rm0zj2O9plGGl-KjdfMA:9","X-Proofpoint-Spam-Details-Enc":"AW1haW4tMjYwNDEzMDE1MSBTYWx0ZWRfX1cfKi/9TePDK\n CTY50vH7dwUZrGtTM0p2lovysbdwAc1sxqN0VwSRGSLHTDnKL2S7OyXL0veZ3wt2SkFewCvGknk\n DDzd8UvuNBYUaQ/kd/BRIBDiC36Et4ax0t1Gw4vQfm5QkDY19rtHT81ks3hjpnWVy3zLbXoNHs3\n tFSdWBLtadlo5fBTVHz5aIzkZMi0dohNWs1iatLpMehFE97T8KupwUnRRC2XhYR8NK9LkuaxuGq\n cApsMABkZv3CuTdFH31WICyb0YIhoPcTWWUHcFomuG6odAwu7Q+QhCfECqaqZWLI6epGi2Q1K4S\n cqR0OXWJbYuV2hfGx3dPGg20bYrt+uF913i4+MVjLH7Q0LeSb4Xbc7EbCPLCGo=","X-Proofpoint-GUID":"_9IVXNzXR01xtAewPb6oyFeBy0jF_rhC","X-Proofpoint-Virus-Version":"vendor=baseguard\n engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49\n definitions=2026-04-13_03,2026-04-13_04,2025-10-01_01","X-Proofpoint-Spam-Details":"rule=notspam policy=default score=0 mlxlogscore=710\n phishscore=0 bulkscore=0 spamscore=0 suspectscore=0\n lowpriorityscore=0\n adultscore=0 clxscore=1030 mlxscore=0 malwarescore=0 classifier=spam\n authscore=0 adjust=0 reason=mlx scancount=1 engine=8.22.0-2601150000\n definitions=main-2604130151","Received-SPF":"pass client-ip=57.103.84.149;\n envelope-from=mohamed@unpredictable.fr; helo=outbound.qs.icloud.com","X-Spam_score_int":"-20","X-Spam_score":"-2.1","X-Spam_bar":"--","X-Spam_report":"(-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1,\n DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001,\n SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham 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":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"AccessHypercallRegs was present twice so clean that up.\n\nRemove TbFlushHypercalls (and its extended Gva range sub-feature)\nfrom the user-mode LAPIC case as it behaves oddly there.\n\nSigned-off-by: Mohamed Mediouni \n---\n target/i386/whpx/whpx-all.c | 9 ++++++---\n 1 file changed, 6 insertions(+), 3 deletions(-)","diff":"diff --git a/target/i386/whpx/whpx-all.c b/target/i386/whpx/whpx-all.c\nindex 2d527b90dd..0908dfd134 100644\n--- a/target/i386/whpx/whpx-all.c\n+++ b/target/i386/whpx/whpx-all.c\n@@ -2489,10 +2489,7 @@ int whpx_accel_init(AccelState *as, MachineState *ms)\n synthetic_features.Bank0.AccessPartitionReferenceTsc = 1;\n synthetic_features.Bank0.AccessHypercallRegs = 1;\n synthetic_features.Bank0.AccessFrequencyRegs = 1;\n- synthetic_features.Bank0.EnableExtendedGvaRangesForFlushVirtualAddressList = 1;\n synthetic_features.Bank0.AccessVpIndex = 1;\n- synthetic_features.Bank0.AccessHypercallRegs = 1;\n- synthetic_features.Bank0.TbFlushHypercalls = 1;\n \n if (whpx_irqchip_in_kernel()) {\n synthetic_features.Bank0.AccessSynicRegs = 1;\n@@ -2500,6 +2497,12 @@ int whpx_accel_init(AccelState *as, MachineState *ms)\n synthetic_features.Bank0.AccessIntrCtrlRegs = 1;\n synthetic_features.Bank0.SyntheticClusterIpi = 1;\n synthetic_features.Bank0.DirectSyntheticTimers = 1;\n+ /*\n+ * These technically work without the Hyper-V LAPIC\n+ * but behave oddly for multi-core VMs.\n+ */\n+ synthetic_features.Bank0.TbFlushHypercalls = 1;\n+ synthetic_features.Bank0.EnableExtendedGvaRangesForFlushVirtualAddressList = 1;\n }\n \n if (is_modern_os && whpx->hyperv_enlightenments_allowed) {\n","prefixes":["v10","03/14"]}