Re: [PATCH] EISA aic7770 broken

["Justin T. Gibbs" <gibbs@scsiguy.com>]

>>>>>> "Justin" == Justin T Gibbs <gibbs@scsiguy.com> writes:
> 
> Justin> Define crashes badly.  Driver messages or kernel panic strings
> Justin> typically help.
> 
> Here it is :
> 
> <quote>
> [...]
> (scsi1:A:5): 10.000MB/s transfers (10.000MHz, offset 15)
>   Vendor: NEC       Model: CD-ROM DRIVE:464  Rev: 1.05
>   Type:   CD-ROM                             ANSI SCSI revision: 02
> scsi2 : Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA DRIVER, Rev 6.2.28
>         <Adaptec 274X SCSI adapter>
>         aic7770: Twin Channel, A SCSI Id=7, B SCSI Id=7, primary A, 4/253 SCBs
> 
> Unable to handle kernel NULL pointer dereference at virtual address 00000000
>  printing eip:
> c01f8cec
> *pde = 00000000
> Oops: 0002
> CPU:    0
> EIP:    0060:[<c01f8cec>]    Not tainted
> EFLAGS: 00010046
> EIP is at ahc_runq_tasklet+0x54/0x140

This is so close to the beginning of the function, that it only makes
sense that "ahc" is NULL.  Can you instrument both ahc_runq_tasklet()
and ahc_platform_alloc() to see if it is indeed the case that "ahc"
is NULL, and to verify that "ahc" was valid when we registered the
tasklet?

--
Justin