Jiaqing Du wrote: > 2009/12/14 Jason Wessel <[email protected]>: > >> Jiaqing Du wrote: >> >>> Hi List, >>> >>> I am trying to use kgdb to debug some kernel modules (mainly for >>> oprofile and kvm). I had some weird problems. For example, break >>> points do not work and the target kernel hangs on a breakpoint to a >>> interrupt handler. Then I compiled the kernel with kgdbts. At least >>> for stable release of 2.6.31.7, it did not pass the testing (with >>> kgdbts=V2). I'm wondering if every stable release really passes the >>> kgdbts testing? Or I'm doing something wrong? >>> >>> >>> >> There was some instability in kgdb with respect to the x86 architecture >> and single stepping on a multi-cpu system. These fixes were merged to >> the 2.6.33 development stream last week. Of course in the 2.6.33 >> kernel the HW breakpoints are presently broken. >> >> I had not yet made a set of patches for the 2.6.32 kernel, but the >> 2.6.33 patch set would certainly apply cleanly. >> >> If you are using kvm, I would recommend not using kgdb, and instead >> using the kvm backend debugger. >> > > What is the kvm backend debugger? After searching KVM mailing list, I > could not find anything. > >
Please look up in the documentation for kvm's user space. -S freeze CPU at startup (use 'c' to start execution) -gdb dev wait for gdb connection on 'dev' -s shorthand for -gdb tcp::1234 That creates a gdb serial communications channel between the kvm instance and a debugger, not unlike using kgdb. Jason. ------------------------------------------------------------------------------ Return on Information: Google Enterprise Search pays you back Get the facts. http://p.sf.net/sfu/google-dev2dev _______________________________________________ Kgdb-bugreport mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport
