From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail3-165.sinamail.sina.com.cn (mail3-165.sinamail.sina.com.cn [202.108.3.165]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D051123C8A0 for ; Sat, 6 Jun 2026 06:15:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.108.3.165 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780726561; cv=none; b=ftyUytaITTVnN846dE61lKJojllC5dPdfsBboqNISUUjelAkhUAz3V58dW4TqHWEIDFQGdL+ypGbUjKH+Aurhfjf6wapQXWg9KxPRc9GzTWwvlok++Wi68tUL0KvT2lpPwlX3NBkKZHGv+Z4F+/w+OPQLsf8Fmc27+FRZJIsWak= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780726561; c=relaxed/simple; bh=cPmUrpINM1hF4hM0WrsgeujoMJdTnn5fDSbEMdwRRLQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VVAXq9o8SSLeNqPWhNiKYrW8sspFYKlSOAifwC3cObL34OxauqxWRopj5UGt5/5xGkzF2xlufRTu9HRDne9WcOK1CI9hA/QHmcfMpKq/j4PC8FFHELPUFV6zZ1n3ayeO9uEZNkYroz3UxmMjoZhj2AXiuG12nOP45x4PrDjhgUU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b=jDpmrq2C; arc=none smtp.client-ip=202.108.3.165 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b="jDpmrq2C" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1780726557; bh=1Nl3O0IPkpkcQ20zgzhHEnaZusy6h5tP5jS8vPwFgEY=; h=From:Subject:Date:Message-ID; b=jDpmrq2Ct5v+We5F6kahwxuMTAYM4RfZerjOgSXdhDjH2xrAtabo+30CWXgF5CoT/ MPjCdB7NYxHqExw2YB7adn4ZevM3S1y+6/gKDLuF0kQ7QwwBe+vNekEKhpd95/mRdq tt1Mrwkl/DcbL5Bf7IJmMyu/kDzYF/SK87/XLa2o= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.62.144]) by sina.com (10.54.253.33) with ESMTP id 6A23BAEF00004D5E; Sat, 6 Jun 2026 14:15:14 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 6478196685144 X-SMAIL-UIID: 98976846C315458AB8254C00D1114EF1-20260606-141514-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [kvm?] [kvm-x86?] INFO: rcu detected stall in kvm_vcpu_ioctl (4) Date: Sat, 6 Jun 2026 14:14:59 +0800 Message-ID: <20260606061501.1554-1-hdanton@sina.com> In-Reply-To: <694f53ba.050a0220.35954c.0084.GAE@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Fri, 26 Dec 2025 19:34:18 -0800 [thread overview] > Hello, > > syzbot found the following issue on: > > HEAD commit: cc3aa43b44bd Add linux-next specific files for 20251219 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=1252109a580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=f7a09bf3b9133d9d > dashboard link: https://syzkaller.appspot.com/bug?extid=3d5461510f8dc4adfe30 > compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14eb1022580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13cc18fc580000 #syz test --- x/arch/x86/kvm/hyperv.c +++ y/arch/x86/kvm/hyperv.c @@ -657,10 +657,8 @@ static int stimer_start(struct kvm_vcpu_ stimer->index, time_now, stimer->exp_time); - hrtimer_start(&stimer->timer, - ktime_add_ns(ktime_now, - 100 * (stimer->exp_time - time_now)), - HRTIMER_MODE_ABS); + hrtimer_forward_now(&stimer->timer, + ns_to_ktime(100 * (stimer->exp_time - time_now))); return 0; } stimer->exp_time = stimer->count; @@ -679,9 +677,7 @@ static int stimer_start(struct kvm_vcpu_ stimer->index, time_now, stimer->count); - hrtimer_start(&stimer->timer, - ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)), - HRTIMER_MODE_ABS); + hrtimer_forward_now(&stimer->timer, ns_to_ktime(100 * (stimer->count - time_now))); return 0; } --- x/drivers/nvme/host/tcp.c +++ y/drivers/nvme/host/tcp.c @@ -3046,6 +3046,8 @@ static int __init nvme_tcp_init_module(v if (wq_unbound) wq_flags |= WQ_UNBOUND; + else + wq_flags |= WQ_PERCPU; nvme_tcp_wq = alloc_workqueue("nvme_tcp_wq", wq_flags, 0); if (!nvme_tcp_wq) --