From owner-freebsd-arm@freebsd.org Tue Apr 26 21:28:43 2016 Return-Path: Delivered-To: freebsd-arm@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 663DFB1DB4C for ; Tue, 26 Apr 2016 21:28:43 +0000 (UTC) (envelope-from onwahe@gmail.com) Received: from mail-io0-x22d.google.com (mail-io0-x22d.google.com [IPv6:2607:f8b0:4001:c06::22d]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 312BD103B for ; Tue, 26 Apr 2016 21:28:43 +0000 (UTC) (envelope-from onwahe@gmail.com) Received: by mail-io0-x22d.google.com with SMTP id 190so23313265iow.1 for ; Tue, 26 Apr 2016 14:28:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc; bh=PFcPEg0AlFTtC7dkqTnDHHwrucoJLwFjlQe+JIZhPNM=; b=DAWIhLcaKTYApuMGYV5OM3b94fir2AiI1G6iLdf56i8jf6YDpOZB0wwndHebTv4KkO wd1CNougnbvQccLAdjYkuKl66ohpASpXj7wvvoUFU3x1fWmYleeJAYV6RWTOhlqMxh9j WIehLAgRtzjlQ+77Usoo6BrK0b7Lp7UvJDghUTL+sszo6arayl0wAWaXoGJHg1Sw7VIV pLOJvhaPkhHIcSQ9u9aI1eyyfEIYJ1fF16jSPNLOX7vP5TP7BPDfXZ8flXFta87mlXL3 TE802xNVRb2lXt9+LS5SkUuuIIFDfGq8WYES0qG73Tj4Q7Fq0BBhKmUiUB2Olv+CdNSx 94CA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc; bh=PFcPEg0AlFTtC7dkqTnDHHwrucoJLwFjlQe+JIZhPNM=; b=C6wd/KShGiXoBUImKpLVNkLgapmmLFYqEEwsbfwDd9mOYeEoD1G/e5dq2MUYfy7a0I wW3DANb2o41c2f6/eJgi7I3s5cqXd67N6IC4YgXhakxUW7VBzEm7GNcL2t5zT3N1Q9Ki G4tI7d28r1R/wEVD+FQkanDryYTYIbJ5kCWABfceXXDXYoTXlZXgAC8tlkMihBQGwN3J MIvPCnRTNrs+iRdexy/cENVVmKN2/4KvV70Rpg8rDnGBBgy8j009Cb+gV3rLxYR6iBfd W3IVe1aXbWGFHjXSEY7Kq3Ddo8w0W6o3LEkhOzDPMivZxWJDHXX15zKrBlGNtyrvbiJg z7VQ== X-Gm-Message-State: AOPr4FXCxnr4MfzTIs/9XHtRdF7U3a8mr772+v9Rt8QvVxTbCk6wzk2xYitb+Pmhd3d9zrGWpV4NfkdCpZOJug== MIME-Version: 1.0 X-Received: by 10.107.23.131 with SMTP id 125mr6472354iox.186.1461706122604; Tue, 26 Apr 2016 14:28:42 -0700 (PDT) Received: by 10.64.93.100 with HTTP; Tue, 26 Apr 2016 14:28:42 -0700 (PDT) In-Reply-To: <20160426204016.GO71221@www.zefox.net> References: <20160426183030.GN71221@www.zefox.net> <20160426204016.GO71221@www.zefox.net> Date: Tue, 26 Apr 2016 23:28:42 +0200 Message-ID: Subject: Re: Another reboot hang From: Svatopluk Kraus To: bob prohaska Cc: "freebsd-arm@freebsd.org" Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 Apr 2016 21:28:43 -0000 On Tue, Apr 26, 2016 at 10:40 PM, bob prohaska wrote: > On Tue, Apr 26, 2016 at 10:18:24PM +0200, Svatopluk Kraus wrote: >> > exception_exit() at exception_exit >> > pc = 0xc05687fc lr = 0xc0515a44 (ffs_sync+0x104) >> > sp = 0xd75ebb88 fp = 0xd75ebba8 >> > r0 = 0x00000004 r1 = 0xc3a5f000 >> > r2 = 0xc3fdb2c0 r3 = 0xc3a5f000 >> > r4 = 0xc0620546 r5 = 0x00000001 >> > r6 = 0xc3fdb2c0 r7 = 0x00000608 >> > r8 = 0x00000000 r9 = 0xc3fdb2b0 >> > r10 = 0xd75ebbf0 r12 = 0xc061cf05 >> >> The break to debugger happened here. So system was in >> __mtx_lock_flags() called from ffs_sync(). It's impossible to say from >> the backtrace if system was stuck or you just break it there. However, >> interrupts was working, so system was not dead totally. One method how >> to learn more is to break to debugger repeatedly to see if system is >> stuck to one place or not. You also can try to type the following >> commands in ddb to see if there is any deadlock. >> >> show all pcpu >> show all procs >> show all locks >> >> For the second command, kernel must be built with WITNESS option. >> > > In past occurences I've waited considerably longer than the normal > reboot time, so it really did seem stuck. The hangs aren't repeatable, > so I'll try the first and third comands at the next opportunity and > turn on WITNESS as a last resort; it really slows the machine down. Hmm, it's third command which needs WITNESS option. I added 'show all pcpu' on first place later and did not fix the reference. By breaking to debugger repeatedly I mean - type 'c' in ddb ('continue' command) and then break to debugger again. > > Thanks for your help! > > bob prohaska >