Subject: Re: sh core dumps
To: None <>
From: David Laight <>
List: port-sparc
Date: 10/19/2005 22:30:50
On Thu, Oct 20, 2005 at 12:47:00AM +0400, Valeriy E. Ushakov wrote:
> [Starting a new thread to disentangle this from the -mcpu discussion]
> The instruction at pc looks totally innocent.
> (gdb) x/7i $pc-20
> 0x17400 <argstr+324>:   cmp  %l6, 0
> 0x17404 <argstr+328>:   sethi  %hi(0x31000), %l3
> 0x17408 <argstr+332>:   be  0x17434 <argstr+376>
> 0x1740c <argstr+336>:   sethi  %hi(0x30c00), %l7
> 0x17410 <argstr+340>:   ld  [ %l3 + 0x310 ], %g1
> 0x17414 <argstr+344>:   add  %g1, -1, %g1		# <-- pc
> 0x17418 <argstr+348>:   cmp  %g1, 0			# <-- npc
> g1             0xe804068c       -402389364

Some thoughts...

That value (in %g1) should (probably) never ever end up in a register
in user-space.

Those values for pc and npc are extremely unlikely to end up in the kernel.
Two (obvious) possibilities:
a) a hardware interrupt
b) a fault on the previous instruction that happens after pc is incremented.

So why might it have gone through the fault => core dump path at all?


David Laight: