Re: how to debug mips AdEL error？ Cause register's ExcCode field equal to '4' (AdEL)

[Bob Zhang <2004.zhang@gmail.com>]

through the kernel panic info:
CPU Regs : ===========================================================
$0 : 00000000 80290000 00000100 fffdffff 00000007 00000006 8023427c 820e83d4
$8 : 00000000 00000000 00000000 820e83dc 820e83f4 820e8000 80278010 00000000
$16: 8028f7b8 0000d32b 0000132b 802a53a0 0000d34d 7fff7d48 00000004 00000014
$24: 8200000c 2abe4090                   820e8000 820e9e70 00000000 0000000a

we can know , the ra register is 0x0000000a
after sub-function executed completely , it will return $ra.

through code trace , I know the last function is "__call_console_drivers" .

I dissable the vmlinux code,

and grab section:

00000000800b9364 <__call_console_drivers>:
    800b9364:	27bdffd8 	addiu	$sp,$sp,-40
    800b9368:	afb00010 	sw	$s0,16($sp)
    800b936c:	3c108028 	lui	$s0,0x8028
    800b9370:	8e107d1c 	lw	$s0,32028($s0)
    800b9374:	afb10014 	sw	$s1,20($sp)
    800b9378:	00808821 	move	$s1,$a0
    800b937c:	afb40020 	sw	$s4,32($sp)
    800b9380:	00a0a021 	move	$s4,$a1
    800b9384:	afbf0024 	sw	$ra,36($sp)    #save ra into SP
    800b9388:	afb3001c 	sw	$s3,28($sp)
    800b938c:	12000012 	beqz	$s0,800b93d8 <__call_console_drivers+74>
    800b9390:	afb20018 	sw	$s2,24($sp)
    800b9394:	32323fff 	andi	$s2,$s1,0x3fff
    800b9398:	3c13802a 	lui	$s3,0x802a
    800b939c:	267353a0 	addiu	$s3,$s3,21408
    800b93a0:	9602001c 	lhu	$v0,28($s0)
    800b93a4:	30420004 	andi	$v0,$v0,0x4
    800b93a8:	50400009 	beqzl	$v0,800b93d0 <__call_console_drivers+6c>
    800b93ac:	8e100024 	lw	$s0,36($s0)
    800b93b0:	8e020008 	lw	$v0,8($s0)
    800b93b4:	50400006 	beqzl	$v0,800b93d0 <__call_console_drivers+6c>
    800b93b8:	8e100024 	lw	$s0,36($s0)
    800b93bc:	02002021 	move	$a0,$s0
    800b93c0:	02532821 	addu	$a1,$s2,$s3
    800b93c4:	0040f809 	jalr	$v0
    800b93c8:	02913023 	subu	$a2,$s4,$s1
    800b93cc:	8e100024 	lw	$s0,36($s0)
    800b93d0:	5600fff4 	bnezl	$s0,800b93a4 <__call_console_drivers+40>
    800b93d4:	9602001c 	lhu	$v0,28($s0)
    800b93d8:	8fbf0024 	lw	$ra,36($sp)
    800b93dc:	8fb40020 	lw	$s4,32($sp)
    800b93e0:	8fb3001c 	lw	$s3,28($sp)
    800b93e4:	8fb20018 	lw	$s2,24($sp)
    800b93e8:	8fb10014 	lw	$s1,20($sp)
    800b93ec:	8fb00010 	lw	$s0,16($sp)
    800b93f0:	03e00008 	jr	$ra                      # error should be here.
    800b93f4:	27bd0028 	addiu	$sp,$sp,40



Any comment? thanks.