From owner-freebsd-acpi@FreeBSD.ORG Fri Dec 4 21:21:06 2009 Return-Path: Delivered-To: freebsd-acpi@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 555951065670 for ; Fri, 4 Dec 2009 21:21:06 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 91C888FC0A for ; Fri, 4 Dec 2009 21:21:05 +0000 (UTC) Received: from porto.topspin.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id XAA24035; Fri, 04 Dec 2009 23:21:01 +0200 (EET) (envelope-from avg@icyb.net.ua) Received: from localhost.topspin.kiev.ua ([127.0.0.1]) by porto.topspin.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1NGfaG-000Jqx-T9; Fri, 04 Dec 2009 23:21:01 +0200 Message-ID: <4B197D0E.1020400@icyb.net.ua> Date: Fri, 04 Dec 2009 23:20:14 +0200 From: Andriy Gapon User-Agent: Thunderbird 2.0.0.23 (X11/20091128) MIME-Version: 1.0 To: "Moore, Robert" References: <4B178387.4050601@icyb.net.ua> <4911F71203A09E4D9981D27F9D8308583E8F26CF@orsmsx503.amr.corp.intel.com> <4B189CD6.30906@icyb.net.ua> <4911F71203A09E4D9981D27F9D8308583E8F2A1F@orsmsx503.amr.corp.intel.com> <4B1975EE.5070803@icyb.net.ua> <4911F71203A09E4D9981D27F9D8308583E8F2BA9@orsmsx503.amr.corp.intel.com> In-Reply-To: <4911F71203A09E4D9981D27F9D8308583E8F2BA9@orsmsx503.amr.corp.intel.com> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "freebsd-acpi@freebsd.org" , Tarick Subject: Re: panic in AcpiExReleaseMutex X-BeenThere: freebsd-acpi@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: ACPI and power management development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 04 Dec 2009 21:21:06 -0000 on 04/12/2009 22:59 Moore, Robert said the following: > It would appear that a GPE is taken, for the EC device, thus invoking > EcGpeQueryHandler. In what context is _Q20 or _Q09 executed? It's invoked in "polling mode" at that stage. Interrupts are not enabled yet at that point. Let me quote my original report: [quote] _REG method seems to access some registers in EC address space (with \_SB.PCI0.LPC0.EC0.MUT1 mutex locked). That access triggers a call to EcSpaceHandler. Now, we have a code in EcSpaceHandler that makes a direct call to EcGpeQueryHandler during a cold boot phase if SCI bit is set in CSR register. EcGpeQueryHandler performs an EC query and executes _Qxx method if need. [/quote] So, everything happens in the same thread with the same context and stack. > This might be an important question: What is the thread_id of this initial > thread? This thread has a fixed tid of 100000. >> -----Original Message----- From: Andriy Gapon [mailto:avg@icyb.net.ua] >> Sent: Friday, December 04, 2009 12:50 PM To: Moore, Robert Cc: >> freebsd-acpi@freebsd.org; Tarick Subject: Re: panic in AcpiExReleaseMutex >> >> on 04/12/2009 20:45 Moore, Robert said the following: >>> Yes, you are correct. I did not have the code in front of me at the time. >>> >>> >>> >>> >>> When AcpiExReleaseMutex is called, apparently the mutex is in fact held, >>> otherwise the function would have aborted immediately. >>> >>> When the mutex is held, the Thread->AcquiredMutexList is expected to hold >>> >>> >>> >> (at >>> the minimum) the mutex object being released. Something is very wrong if >> this >>> list is NULL when releasing the mutex. >>> >>> Just to make sure: All of this is happening in the same thread? >> Yes, this happens when there is only the initial thread running on BSP, no >> other threads are started yet. >> >> >> -- Andriy Gapon -- Andriy Gapon