[Bug 206044] devel/gdb: Misc KGDB fixes

bugzilla-noreply at freebsd.org bugzilla-noreply at freebsd.org
Fri Jan 8 19:49:10 UTC 2016


https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=206044

            Bug ID: 206044
           Summary: devel/gdb: Misc KGDB fixes
           Product: Ports & Packages
           Version: Latest
          Hardware: Any
                OS: Any
            Status: New
          Severity: Affects Only Me
          Priority: ---
         Component: Individual Port(s)
          Assignee: freebsd-ports-bugs at FreeBSD.org
          Reporter: jhb at FreeBSD.org
                CC: luca.pizzamiglio at gmail.com
             Flags: maintainer-feedback?(luca.pizzamiglio at gmail.com)
                CC: luca.pizzamiglio at gmail.com

Created attachment 165277
  --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=165277&action=edit
gdb_port_kgdb2.patch

The enclosed patches fix three separate issues in kgdb and bump the
portrevision (since KGDB is enabled by default):

- kgdb -n now permits any valid string to be used instead of only permitting
  numbers.  In particular, this allows 'kgdb -n last' to be used to open the
  most recent vmcore.
- kgdb will now try to determine the list of kernel modules even if the kernel
  binary does not include debug symbols.  This works fine in kernels that have
  the changes in r290728.
- Mark trapframes as "signal trampoline frames".  GDB assumes that "normal"
  frames will never call into a NULL PC.  Instead, it assumes that calling a
  NULL PC will result in an exception (and thus a signal being posted resulting
  in a signal frame).  A trap for a NULL function pointer would thus stop
  unwinding once it hit the frame with a NULL PC.  Marking the trapframes as
  a signal frame tells GDB it is ok to unwind past a NULL PC.  One side
  effect is that frames in the asm handler now display as "signal handler
called"
  instead of the raw line in assembly.  Perhaps at some point it would be
  nice to mark these up the way ddb does with the trap number, etc. but GDB's
  stack code doesn't support custom frame printers.

-- 
You are receiving this mail because:
You are the assignee for the bug.


More information about the freebsd-ports-bugs mailing list