November 2011 - Darwin-kernel

Re: Setting up two-machine kernel debugging via firewire
by Shantonu Sen 03 Nov '11

03 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com You should file a bug report at bugreport.apple.com asking that it be made available. In this particular case the kernel didn't change between the builds (so it might kind of look like it works), but other content that contributes to the Kernel Debug Kit did change, so you might see strange behavior until you get it synchronized. I'd recommend using --arch=x86_64 at the start of your gdb invocation. Shantonu On Nov 3, 2011, at 5:48 AM, mailist(a)ericgorr.net wrote: > On Thu, 03 Nov 2011 05:18:34 -0700, Shantonu Sen wrote: >> kdp-reattach lets you steal a connection in case someone else is >> currently attached. It can also help in cases where a debug session is >> interrupted and you need to get the panicked system to just reset its >> internal state machine. > > Thank you for the explanation. It was useful. > >> Are you sure your target is running the 32-bit kernel? What does >> uname -a print before you enter the kernel debugger. > > Brilliant. I was pretty sure I was running a 64-bit kernel and rechecked in the system profiler. In the entry for 64-bit Kernel and Extensions in the Software section, it said yes. > > So, armed with this information, I invoked gdb correctly by doing: > > gdb /Volumes/KernelDebugKit/mach_kernel --arch=x86_64 > > and, now, showallkmods works. > >> Yes, you need to have your kernel debug kit exactly match whatever >> build your target is running. There is no close enough. > > Ok. So, unless I can locate the 10.6.8 10k549 kernel debug kit (which may not even exist), I will need to downgrade the machines to 10.6.7 10J869, which I can find at https://developer.apple.com/downloads...correct? > _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by mailist＠ericgorr.net 03 Nov '11

03 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com User-agent: Roundcube Webmail/0.5.4 Thank you for the explanation. It was useful. Are you sure your target is running the 32-bit kernel? What does uname -a print before you enter the kernel debugger. So, armed with this information, I invoked gdb correctly by doing: gdb /Volumes/KernelDebugKit/mach_kernel --arch=x86_64 and, now, showallkmods works. Yes, you need to have your kernel debug kit exactly match whatever build your target is running. There is no close enough. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… On Thu, 03 Nov 2011 05:18:34 -0700, Shantonu Sen wrote: kdp-reattach lets you steal a connection in case someone else is currently attached. It can also help in cases where a debug session is interrupted and you need to get the panicked system to just reset its internal state machine. Brilliant. I was pretty sure I was running a 64-bit kernel and rechecked in the system profiler. In the entry for 64-bit Kernel and Extensions in the Software section, it said yes. Ok. So, unless I can locate the 10.6.8 10k549 kernel debug kit (which may not even exist), I will need to downgrade the machines to 10.6.7 10J869, which I can find at https://developer.apple.com/downloads...correct? This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by Ken Hornstein 03 Nov '11

03 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com >Because that is what the instructions on http://fieldofcows.com/index.php?title=Setting_up_Kernel_Debugging_on_OS_X say. > >Have you successfully done this? Have I successfully done two-kernel debugging? Yes, absolutely; not using it right this second and I've only done it under Snow Leopard, but for a while it was one of my most useful tools. Not over firewire, though; I used IP. But I don't think that's your problem, since you can attach fine. >Is using kdp-reattach not necessary? Well, I guess I was thinking out loud about the "re"-attach part. I just use "attach" (after running "target remote-kdp"). But from what Shantonu said, it doesn't sound like that's the problem. --Ken _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by Shantonu Sen 03 Nov '11

03 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com kdp-reattach lets you steal a connection in case someone else is currently attached. It can also help in cases where a debug session is interrupted and you need to get the panicked system to just reset its internal state machine. Are you sure your target is running the 32-bit kernel? What does uname -a print before you enter the kernel debugger. Yes, you need to have your kernel debug kit exactly match whatever build your target is running. There is no close enough. Shantonu On Nov 3, 2011, at 5:13 AM, mailist(a)ericgorr.net wrote: > On Wed, 02 Nov 2011 18:48:56 -0400, Ken Hornstein wrote: >>> (gdb) kdp-reattach localhost >>> Connected. >> >> Stupid question time: how come you're using kdp-reattach, rather than >> kdp-attach? > > Well, my answer won't be much better. > > Because that is what the instructions on http://fieldofcows.com/index.php?title=Setting_up_Kernel_Debugging_on_OS_X say. > > Have you successfully done this? > > Is using kdp-reattach not necessary? > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/darwin-kernel/ssen%40apple.com > > This email sent to ssen(a)apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by mailist＠ericgorr.net 03 Nov '11

03 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com User-agent: Roundcube Webmail/0.5.4 (gdb) kdp-reattach localhost Connected. Stupid question time: how come you're using kdp-reattach, rather than kdp-attach? Well, my answer won't be much better. Have you successfully done this? Is using kdp-reattach not necessary? _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… On Wed, 02 Nov 2011 18:48:56 -0400, Ken Hornstein wrote: Because that is what the instructions on http://fieldofcows.com/index.php?title=Setting_up_Kernel_Debugging_on_OS_X say. This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by mailist＠ericgorr.net 03 Nov '11

03 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com User-agent: Roundcube Webmail/0.5.4 A long shot, but have you tried explicitly specifying the target architecture using the -arch flag to the gdb? Yes. I invoke gdb by doing the following: $ gdb /Volumes/KernelDebugKit/mach_kernel --arch=i386 _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… On Thu, 3 Nov 2011 00:34:23 +0200, Alexander Dimitrov wrote: This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by Paul Nelson 02 Nov '11

02 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com This usually indicates that you are using the wrong version of the kernel debug kit. Your debug machine does not have to run the exact OS build as the machine being debugged, but the kernel debug kit MUST match the debugged machine right down to the build number. On Nov 2, 2011, at 5:07 PM, mailist(a)ericgorr.net wrote: > The problem is that 'showallkmods' returns an empty list and none of the other similar commands appear to be working: _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by Ken Hornstein 02 Nov '11

02 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com >(gdb) kdp-reattach localhost >Connected. Stupid question time: how come you're using kdp-reattach, rather than kdp-attach? --Ken _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by Alexander Dimitrov 02 Nov '11

02 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=YFrbAj7KLdDQQvgsaQENUX65/E7Y2UJY9Nmgeab9bFs=; b=sX4UApOX6GK2Eb/+On1y1gbTXI3weg2jzhYsDr01Dnlpnq3VVAOrbnrDwGjj9TeyBn 8LYjlSRhaPyrIu1XVdgXAAKFMTAjr7jY4fRKOLzs/QZWTR1hYuCO+vG6L86vFAmx5ikm JyyAOWyUMUTOXZEOTRDI2xxLUZJTLlmHQDq8M= _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Setting up two-machine kernel debugging via firewire
by Joel Reymont 02 Nov '11

02 Nov '11

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=subject:mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to:x-mailer; bh=5CkJoxsPX5wt3dGajmw8Jl0XlQ8JLWODzXBjuPxwcSI=; b=T/S4+9PBdmvL5wmw1poN46I3xrWpRDa7bhHD6b9UX53Y2eHpGHSY/fyAxyqx7AEPMc AbRUe34YV81M+JrvS9GOn8Z+D9BS1I+VNcCEcAH7hyIatELA7eO8slYTAwa36VhTZjiX ySxr8u3LatpJ/G261PHcLtVJPcMGzllqZ2PE0= I mirrored the lists at http://groups.google.com a couple of years ago. On Nov 2, 2011, at 9:07 PM, mailist(a)ericgorr.net wrote: > The archives are down at the moment, so I haven't been able to search through them to see if there is already an answer available to this problem. -------------------------------------------------------------------------- - for hire: mac osx device driver ninja, kernel extensions and usb drivers ---------------------+------------+--------------------------------------- http://wagerlabs.com | @wagerlabs | http://www.linkedin.com/in/joelreymont ---------------------+------------+--------------------------------------- _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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