From owner-freebsd-bugs@FreeBSD.ORG Tue Nov 4 00:08:06 2014 Return-Path: Delivered-To: freebsd-bugs@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id DE0C7F53 for ; Tue, 4 Nov 2014 00:08:06 +0000 (UTC) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id AC767F25 for ; Tue, 4 Nov 2014 00:08:06 +0000 (UTC) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.14.9/8.14.9) with ESMTP id sA4086iL036498 for ; Tue, 4 Nov 2014 00:08:06 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 194796] New: pmcstat(8) paniced a box Date: Tue, 04 Nov 2014 00:08:06 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 10.0-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: hiren@FreeBSD.org X-Bugzilla-Status: Needs Triage X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Nov 2014 00:08:07 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=194796 Bug ID: 194796 Summary: pmcstat(8) paniced a box Product: Base System Version: 10.0-STABLE Hardware: Any OS: Any Status: Needs Triage Severity: Affects Only Me Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: hiren@FreeBSD.org Did "pmcstat -S instructions -T" on a 10-stable (ish) sandybridge xeon box and it paniced. Nov 3 13:51:11 vxs162401 kernel: panic: [pmc,4186] cpu 3 didn't find a sample to collect Nov 3 13:51:11 vxs162401 kernel: cpuid = 3 Nov 3 13:51:11 vxs162401 kernel: KDB: stack backtrace: Nov 3 13:51:11 vxs162401 kernel: db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe1 06dd0d840 Nov 3 13:51:11 vxs162401 kernel: kdb_backtrace() at kdb_backtrace+0x39/frame 0xfffffe106dd0d8f0 Nov 3 13:51:11 vxs162401 kernel: vpanic() at vpanic+0x126/frame 0xfffffe106dd0d930 Nov 3 13:51:11 vxs162401 kernel: kassert_panic() at kassert_panic+0x136/frame 0xfffffe106dd0d9a0 Nov 3 13:51:11 vxs162401 kernel: pmc_capture_user_callchain() at pmc_capture_user_callchain+0x124/fram e 0xfffffe106dd0d9f0 Nov 3 13:51:11 vxs162401 kernel: pmc_hook_handler() at pmc_hook_handler+0x6bf/frame 0xfffffe106dd0dab0 Nov 3 13:51:11 vxs162401 kernel: outofnmi() at outofnmi+0x23/frame 0xffff5be0 Nov 3 13:51:11 vxs162401 kernel: Uptime: 4d14h51m21s >From chat: 14:38 <@davide> hiren: I see nothing in the code preventing the thread to be rescheduled into another cpu from a first look 14:38 <@adrian> *burp* 14:38 <@davide> at the end of pmc_capture_user_callchain() you call sched_unpin() but there's no matching sched_pin() call Need to investigate more. -- You are receiving this mail because: You are the assignee for the bug.