Date: Tue, 16 Nov 2010 22:41:56 +0000 From: Alexander Best <arundel@freebsd.org> To: Marcin Wisnicki <mwisnicki+freebsd@gmail.com> Cc: freebsd-current@freebsd.org Subject: Re: www/chromium crashing whole system Message-ID: <20101116224156.GA52556@freebsd.org> In-Reply-To: <ibsl25$23m$1@dough.gmane.org> References: <20101112223715.GA1356@freebsd.org> <20101113112447.GF2392@deviant.kiev.zoral.com.ua> <20101113115900.GA14975@freebsd.org> <20101113122853.GG2392@deviant.kiev.zoral.com.ua> <20101113123846.GA21390@freebsd.org> <20101113124146.GH2392@deviant.kiev.zoral.com.ua> <20101113124758.GA23469@freebsd.org> <alpine.BSF.2.00.1011132206380.12353@fledge.watson.org> <4CDF0E7F.3060406@freebsd.org> <ibsl25$23m$1@dough.gmane.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue Nov 16 10, Marcin Wisnicki wrote: > On Sat, 13 Nov 2010 14:17:35 -0800, Julian Elischer wrote: > > > On 11/13/10 2:08 PM, Robert Watson wrote: > >> > >> If regular crashdumps appear unreliable, try setting up a textdump with > >> an automatic reboot, that might provde more reliable (small chance, but > >> it could). > > > > we did have some people working on an ethernet version of the > > dcons/remote debugging stuff > > I guess it only supports a small subset of ethernet chips though.. > > Anyone know the status of that work? > > > > I don't know about ethernet dump but how about simply dumping memory after > reset ? > > See: > - http://en.wikipedia.org/wiki/Cold_boot_attack > - http://citp.princeton.edu/memory/ > - http://www.mcgrewsecurity.com/tools/msramdmp/ > > Last link contains a tool to dump memory to usb disk after reset. If kgdb > works with raw memory dumps, it may already work. > > This has the potential to solve all tricky debugging cases without needing > firewire. WOW! this is the first time i hear of such a concept. it seems great for people like me who are desktop users without any serial/firewire consoles or any additional debugging hardware. is there a way of trying this out somehow? personally i wouldn't need the memory dump to work in partitions. i'd simply blug in a blank usb stick and have the memory dump dd'ed onto it. i think adding partition awareness is not really needed. cheers. alex > > A boot time kernel option to avoid certain memory areas which are > overwritten during boot by bios and ram dumping tool could be useful or > maybe necessary. > > It can even be completely automated, eg. if kernel would maintain some > kind of "RAM dirty" flag, then during boot something (loader or kernel) > would check for it and perform dump if needed. > > Another idea worth implementing or at least adding to project ideas list > is to implement everything that is currently possible with serial (boot0, > loader, kernel console, ddb) over EHCI debug port: > - http://www.coreboot.org/EHCI_Debug_Port > -- a13x
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20101116224156.GA52556>