Re: [Crash-utility] [PATCH] ARM: fp when unwinding

----- Original Message ----- > Hi Dave, Mika, Jan and anyone else interested in the Crash ARM > support, > > The table based unwind code potentially unwinds the stack pointer to the > existing value of any other register except the PC: > >       } else if ((insn & 0xf0) == 0x90 && >                  (insn & 0x0d) != 0x0d) { >               /* 1001 nnnn: set vsp = r[nnnn] */ >               ctrl->vrs[SP] = ctrl->vrs[insn & 0x0f]; > >   The 'struct stackframe' we use to keep unwind state when going from > one frame to the next (or should I say previous) only contains fp, sp, > lr and pc, which might be something we should consider changing. Even as > it stands however, frame.fp is assigned an incorrect value for active > tasks. Here's a patch to fix that. > > > diff --git a/unwind_arm.c b/unwind_arm.c > index fd6ac65..6554804 100644 > --- a/unwind_arm.c > +++ b/unwind_arm.c > @@ -710,6 +710,7 @@ unwind_backtrace(struct bt_info *bt) >           */ >          if (bt->machdep) { >                  const struct arm_pt_regs *regs = bt->machdep; > +               frame.fp = regs->ARM_fp; >                  frame.lr = regs->ARM_lr; >          } > > > And this time I did remember to run a 'make warn' =o) > > Regards, > Per I can't comment on the backtrace functionality/query, but the patch looks reasonable -- although it appears that with the current code, as is, it would only affect CRASHDEBUG(5) output in unwind_frame()? Dave -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility