From nobody Tue Feb 08 02:23:55 2022 X-Original-To: virtualization@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 5E8D519A87AE for ; Tue, 8 Feb 2022 02:23:57 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Jt6JX1JHLz4vvG for ; Tue, 8 Feb 2022 02:23:55 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 3D6F0113D0 for ; Tue, 8 Feb 2022 02:23:55 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 2182NtSQ021533 for ; Tue, 8 Feb 2022 02:23:55 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 2182Ntac021532 for virtualization@FreeBSD.org; Tue, 8 Feb 2022 02:23:55 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: virtualization@FreeBSD.org Subject: [Bug 261198] bhyve host panics with: spin lock 0xffffffff81eac800 (callout) helpanic: spin lock held too long Date: Tue, 08 Feb 2022 02:23:55 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bhyve X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: markj@FreeBSD.org X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: virtualization@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Discussion List-Archive: https://lists.freebsd.org/archives/freebsd-virtualization List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-virtualization@freebsd.org X-BeenThere: freebsd-virtualization@freebsd.org MIME-Version: 1.0 ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1644287036; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TtNcxXYIVChAHcgHRAmJPFcouPeAqBEwI1sNXNeIEGs=; b=lVGfkbj+2p0PEBU5n5im5NgA8xzxJYkeao/nX4jprFIAyxArCfAihPwloNAhih/trx87u5 a0KnjRKPw8DYChm2axB3US7hz5Xt0Nt2GGk2TWXkDD/c88i4bqUJW9qKnmDGzzoe6P/woa aBrhWvvsvfb2eJAnuUCVyXB+H8ficLfYi7DOo5BXkdDxX5Dxf5oTHhzAXicaeeoLVxvhG+ zfzFZl4KFd3QksCFW/7Xv5xWVsjaNImQyDjail5DIGXvOajcfs1KLZlI1N8qrIPsJ/0Jdh 8+sdrjSiJgTt9Jmmb9mR3EOWv4Zh8XtTlcZauC2z3zgmk1plgjqzTaRo3LKC1Q== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1644287036; a=rsa-sha256; cv=none; b=l1mGhFKcwyH8Pd0eolZYCuS3KMFJFxWNmhya2ePAOceKN2v2kBG/5l2z6/yzixSrTZhBYQ 9SFBaMu2yW5G84jo4yOWHdj9xw1jtnxcFdDk57hnCdokgwvyBMpgrO+Ee7v/a2Sd4/YdGH /3VOv6pzsv0t4TqpadTxTSKFzy+uuy0lrfGQ5wRLstJxdgB1RAGLaT2Ag7t0JeP3QPVKHc w5u1g5yJgf/1n0W3GkJCZNeiJt70MAY+LozrHyegUPhGlqx81HTKQBmGjrWKoBkd0zQ4Jr jKV3xl6UK9ZRLXRyDPICOsg0UDM44R34Ej1nP0hvN31ie36/KVIcPw0DW+msLw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none X-ThisMailContainsUnwantedMimeParts: N https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D261198 --- Comment #6 from Mark Johnston --- Looks like there is a lock order reversal: sleepq_signal() selects a thread= on the sleepqueue, locks it, and then sleepq_remove_thread() stops the td_slpcallout callout, which requires a per-CPU callout lock.=20 softclock_thread() locks the per-CPU callout lock and then acquires the cur= rent thread's lock. Usually the thread selected by sleepq_signal() will have its lock set to th= at of the sleepqueue, and no deadlock is possible. But if the thread is prepa= ring to go to sleep, its lock will still be a scheduler lock. So it's not very = easy to hit this deadlock. --=20 You are receiving this mail because: You are the assignee for the bug.=