Messages in this thread |  | | | Date | Fri, 27 Feb 2004 13:58:05 -0800 | | From | George Anzinger <> | | Subject | Re: kgdb support in vanilla 2.6.2 |
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Piet Delaney wrote: > On Tue, 2004-02-10 at 13:56, George Anzinger wrote: > > I thought I'd poke around an AMD64 with etherbased kgdb on 2.6.*. > I just picked up a used AMD64 K8D Master-F MS-9131 and thought I'd > install Fedora Core 1 test1 and the latest kernel from kernel.org. > > It Might be interesting to try out a SuSE release also, I was wondering > if 9.0 from linuxiso.org might be best. > > Last I worked with your kgdb patch for 2.6 Andrew's mm patch had the > latest code; Is that still the case?
I think so. I haven't look lately. I did send out an additional patch that only put in dwarft2 records in some of the asm code to allow better "bt" through the interrupt/exception frames. I don't know if he picked this up or not, but it does require using the cvs version of gdb.
-g > > -piet > > >>Andi Kleen wrote: >> >>>On Thu, 5 Feb 2004 23:20:04 +0530 >>>"Amit S. Kale" <amitkale@emsyssoft.com> wrote: >>> >>> >>> >>>>On Thursday 05 Feb 2004 8:41 am, Andi Kleen wrote: >>>> >>>> >>>>>Andrew Morton <akpm@osdl.org> writes: >>>>> >>>>> >>>>>>need to take a look at such things and really convice ourselves that >>>>>>they're worthwhile. Personally, I'd only be interested in the basic >>>>>>stub. >>>>> >>>>>What I found always extremly ugly in the i386 stub was that it uses >>>>>magic globals to talk to the page fault handler. For the x86-64 >>>>>version I replaced that by just using __get/__put_user in the memory >>>>>accesses, which is much cleaner. I would suggest doing that for i386 >>>>>too. >>>> >>>>May be I am missing something obvious. When debugging a page fault handler if >>>>kgdb accesses an swapped-out user page doesn't it deadlock when trying to >>>>hold mm semaphore? >>> >>> >>>Modern i386 kernels don't grab the mm semaphore when the access is >= TASK_SIZE >>>and the access came from kernel space (actually I see x86-64 still does, but that's >>>a bug, will fix). You could only see a deadlock when using user addresses >>>and you already hold the mm semaphore for writing (normal read lock is ok). >>>Just don't do that. >>> >>> >>> >>> >>>>George has coded cfi directives i386 too. He can use them to backtrace past >>>>irqs stack. >>> >>> >>>Problem is that he did it without binutils support. I don't think that's a good >>>idea because it makes the code basically unmaintainable for normal souls >>>(it's like writing assembly code directly in hex) >> >>Well, bin utils, at this time, makes it even worse in that it does not support >>the expression syntax. Also, it is not asm but dwarf2 and it is written in, >>IMHO, useful macros (not hex :) >> >> >> >>-- >>George Anzinger george@mvista.com >>High-res-timers: http://sourceforge.net/projects/high-res-timers/ >>Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml >> >>- >>To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >>the body of a message to majordomo@vger.kernel.org >>More majordomo info at http://vger.kernel.org/majordomo-info.html >>Please read the FAQ at http://www.tux.org/lkml/
-- George Anzinger george@mvista.com High-res-timers: http://sourceforge.net/projects/high-res-timers/ Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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