{"id":2224819,"url":"http://patchwork.ozlabs.org/api/patches/2224819/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260418223320.51330-5-mohamed@unpredictable.fr/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/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":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260418223320.51330-5-mohamed@unpredictable.fr>","list_archive_url":null,"date":"2026-04-18T22:32:46","name":"[04/38] 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/people/91318/?format=json","name":"Mohamed Mediouni","email":"mohamed@unpredictable.fr"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260418223320.51330-5-mohamed@unpredictable.fr/mbox/","series":[{"id":500475,"url":"http://patchwork.ozlabs.org/api/series/500475/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=500475","date":"2026-04-18T22:32:54","name":"WHPX x86 updates for QEMU 11.1","version":1,"mbox":"http://patchwork.ozlabs.org/series/500475/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2224819/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2224819/checks/","tags":{},"related":[],"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=YecgrCAj;\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 4fymlG0yGVz1yGt\n\tfor ; Sun, 19 Apr 2026 08:34:34 +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 1wEEEP-00064L-0T; Sat, 18 Apr 2026 18:33:41 -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 1wEEEN-00063I-21\n for qemu-devel@nongnu.org; Sat, 18 Apr 2026 18:33:39 -0400","from p-east2-cluster5-host5-snip4-5.eps.apple.com ([57.103.79.88]\n helo=outbound.st.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 1wEEEL-0004ou-He\n for qemu-devel@nongnu.org; Sat, 18 Apr 2026 18:33:38 -0400","from outbound.st.icloud.com (unknown [127.0.0.2])\n by p00-icloudmta-asmtp-us-east-1a-100-percent-1 (Postfix) with ESMTPS id\n 871A31800226; Sat, 18 Apr 2026 22:33:33 +0000 (UTC)","from localhost.localdomain (unknown [17.42.251.67])\n by p00-icloudmta-asmtp-us-east-1a-100-percent-1 (Postfix) with ESMTPSA id\n E37B818000A8; Sat, 18 Apr 2026 22:33:30 +0000 (UTC)"],"Dkim-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=unpredictable.fr;\n s=sig1; t=1776551616; x=1779143616;\n bh=LeCfULzXVq8eMeXoD4HoazACVFGuCL5m06fQgObX99k=;\n h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme;\n b=YecgrCAjwcpFWLshUV7a3YCFOs3Zu2gBxRuS6mxp2GVm/oLA2qWGCFw8Qe9zH+MvczPsvAycKYwIWnLcvErPGjoK2m7eA1UiYNSlq0ls8gST9NwUdoNYMLHywBWW2uFiB+sloyrrm0mBHDmf7XL0G8BNiO5dbhgUk1g/XiaPtJSBXp51uSGctjK4AlJbUatbFol1nU4XFwxfmcj6OOQjdexKDWssVOA79bBlHkcjksv3czssPrgTLYvBnRcS80lsAJnnc/SqicDxtHKlzNO8hBTqRftdEZJuKNjbPZQa0dMDP/AH4RNt/H3+sIwROfkqgj3zm0kAuefaPAtC0KvKZA==","mail-alias-created-date":"1752046281608","From":"Mohamed Mediouni ","To":"qemu-devel@nongnu.org","Cc":"Mohamed Mediouni ,\n \"Michael S. Tsirkin\" , Paolo Bonzini ,\n Zhao Liu , Pedro Barbuda ,\n Roman Bolshakov , qemu-arm@nongnu.org,\n Pierrick Bouvier ,\n Peter Maydell , Wei Liu ,\n Phil Dennis-Jordan ","Subject":"[PATCH 04/38] whpx: i386: disable TbFlushHypercalls for emulated\n LAPIC","Date":"Sun, 19 Apr 2026 00:32:46 +0200","Message-ID":"<20260418223320.51330-5-mohamed@unpredictable.fr>","X-Mailer":"git-send-email 2.50.1","In-Reply-To":"<20260418223320.51330-1-mohamed@unpredictable.fr>","References":"<20260418223320.51330-1-mohamed@unpredictable.fr>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Authority-Info-Out":"v=2.4 cv=QIRlhwLL c=1 sm=1 tr=0 ts=69e406bf\n cx=c_apl:c_pps:t_out a=YrL12D//S6tul8v/L+6tKg==:117\n a=YrL12D//S6tul8v/L+6tKg==:17 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22\n a=Rm0zj2O9plGGl-KjdfMA:9","X-Proofpoint-Spam-Details-Enc":"AW1haW4tMjYwNDE4MDIyOCBTYWx0ZWRfX4Wpczo0CCtF5\n dZCi+5/wJmCDai17CoPMp7QvFWL7lVuxEgQhE1I1VKDx5Bhng2vyGzl9TVffNKiur5Hyth4b8Wn\n Xam6NnvgNw7X+crhNG3sFTP+w+BGLdZ6+ZjP7hAnQ4QQXdZQGwNi7zmcnyfXZx6I8x3CRXHWyKz\n RdyFvwZod9EhE/2JkMkx3zP01MMI/kyv3d7+3bnTbcB4JpRDl1lNTm7L8r47uB6uHC+WArRtzMD\n MG8nQMonvMAFs56dmhyoOH8gxZEq9xpHh0mel37yjvBHxmmbMKarJAPyxCrnJTM/hU2oJygK7X4\n g6iv5yUj5qo0lVYOuKlPPDkSr3X1W1D96zQ1pouSsTpVugYWHP9SCD/nzFqp18=","X-Proofpoint-ORIG-GUID":"Q3CceVXSqfdkQqn1sTKjbfIyOQJBJDLh","X-Proofpoint-GUID":"Q3CceVXSqfdkQqn1sTKjbfIyOQJBJDLh","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=2026-04-18_06,2026-04-17_04,2025-10-01_01","X-Proofpoint-Spam-Details":"rule=notspam policy=default score=0 suspectscore=0\n mlxlogscore=777 spamscore=0 malwarescore=0\n adultscore=0 bulkscore=0\n lowpriorityscore=0 clxscore=1030 phishscore=0 mlxscore=0 classifier=spam\n authscore=0 adjust=0 reason=mlx scancount=1 engine=8.22.0-2601150000\n definitions=main-2604180228","Received-SPF":"pass client-ip=57.103.79.88;\n envelope-from=mohamed@unpredictable.fr; helo=outbound.st.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":["04/38"]}