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 lists1p.gnu.org (lists1p.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 F0F7DC55173 for ; Fri, 31 Jul 2026 18:48:13 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wpsGG-0003xI-3d; Fri, 31 Jul 2026 14:47:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wpsG7-0003wG-Jx for qemu-devel@nongnu.org; Fri, 31 Jul 2026 14:47:04 -0400 Received: from linux.microsoft.com ([13.77.154.182]) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wpsG6-0000lM-8H for qemu-devel@nongnu.org; Fri, 31 Jul 2026 14:47:03 -0400 Received: from laptop.localdomain (unknown [86.121.140.206]) by linux.microsoft.com (Postfix) with ESMTPSA id 85E1A20B7167; Fri, 31 Jul 2026 11:46:41 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 85E1A20B7167 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1785523603; bh=qzAKGinRpTm7h9cD+exUNPykINEVxI273EsPRDaQ1E8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jmbONyokHCE5sRvjv4mErLWcOwkosw3KQ/aUoiQDw4/eZ53A2P9b2qfMib47tNTjG Ftn08YevzjzzyqfLQl/hXZ8gI46+r6aaIicOBDtZRp4puoAkGXYFRn/AP1C+iJNjjM CVIQwp1O8PXXq/B9gqLWkWfef2yJ7G/71s3acz/w= From: =?UTF-8?q?Doru=20Bl=C3=A2nzeanu?= To: qemu-devel@nongnu.org Cc: Wei Liu , Wei Liu , Magnus Kulke , =?UTF-8?q?Doru=20Bl=C3=A2nzeanu?= , =?UTF-8?q?Doru=20Bl=C3=A2nzeanu?= , Magnus Kulke Subject: [PATCH v2 4/4] accel/mshv: break the vCPU run loop on exit_request Date: Fri, 31 Jul 2026 21:46:42 +0300 Message-ID: <20260731184643.89604-5-dblanzeanu@linux.microsoft.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260731184643.89604-1-dblanzeanu@linux.microsoft.com> References: <20260731184643.89604-1-dblanzeanu@linux.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=13.77.154.182; envelope-from=dblanzeanu@linux.microsoft.com; helo=linux.microsoft.com X-Spam_score_int: -19 X-Spam_score: -2.0 X-Spam_bar: -- X-Spam_report: (-2.0 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, 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: , 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 Ignored VM exits can cause mshv_cpu_exec() to re-enter MSHV_RUN_VP without returning to qemu_process_cpu_events(). A busy vCPU may prevent pause_all_vcpus() from completing. Check exit_request before re-entering MSHV_RUN_VP and return EXCP_INTERRUPT so pending stop requests can be processed. Signed-off-by: Doru Blânzeanu --- accel/mshv/mshv-all.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/accel/mshv/mshv-all.c b/accel/mshv/mshv-all.c index afcb87b3b8..b7c1126fe0 100644 --- a/accel/mshv/mshv-all.c +++ b/accel/mshv/mshv-all.c @@ -780,6 +780,16 @@ static int mshv_cpu_exec(CPUState *cpu) cpu->vcpu_dirty = false; } + /* + * A kick/stop can't reliably break MSHV_RUN_VP out, so leave the run + * loop here too; otherwise a busy vCPU never reaches + * qemu_process_cpu_events() and pause_all_vcpus() hangs under the BQL. + */ + if (cpu->stop || qatomic_load_acquire(&cpu->exit_request)) { + ret = EXCP_INTERRUPT; + break; + } + ret = mshv_run_vcpu(mshv_state->vm, cpu, &mshv_msg, &exit_reason); if (ret < 0) { error_report("Failed to run on vcpu %d", cpu->cpu_index); -- 2.53.0