Re: aic7xxx: aic7892(B): BUG: soft lockup detected on CPU#0!

[thomas schorpp <t.schorpp@gmx.de>]

thomas schorpp wrote:
> James Bottomley wrote:
>> On Sat, 2007-03-24 at 01:51 +0100, thomas schorpp wrote:
>>>> no. so the pci layer reports wrong start:
>>> nonsense. it succeeds, confused function return with the error flag:
>>>
>>> //      u_long  start;
>>> //      u_long  start = 0xFFEFF000;
>>>         u_long  start = 0x30000000;
>>>         int     error;
>>>
>>>         struct resource* ret1;
>>>         error = 0;
>>> //      start = pci_resource_start(ahc->dev_softc, 1);
>>>         if (start != 0) {
>>>                 *bus_addr = start;
>>>                 if ((ret1 = request_mem_region(start, 0x1000, 
>>> "aic7xxx")) == 0)
>>
>> You can't do this.  The pci_resource_start is getting the address of
>> something called a Bus Address Register (BAR) it says in physical
>> address space where the card is responding ... you can't simply set that
>> to a random value.
>>
>> The problem you seem to have is that your system is reporting a BAR
>> beyond 32 bits (4GB) which the card physically can't use.  This could be
>> because of a BIOS misconfiguration or because there's a bug in the PCI
>> subsystem somewhere.
>>
>> James
> 
> understood. waiting for LKML answers... meanwhile i found harder reason 
> for a possible bounds problem with the driver code on x86_64:
> 
> if i do:
> 
> static int
> ahc_linux_pci_reserve_mem_region(struct ahc_softc *ahc,
>                                 u_long *bus_addr,
>                                 uint8_t __iomem **maddr)
> {
> //      u_long  start;
>        uint32_t start;
> 
> i get no free warning of "*nonexistant* resource" (it cant be 
> nonexistant, cause it was definitely something mapped):
> 
> tom1:/usr/src/linux# dmesg |grep -i free
> Freeing unused kernel memory: 208k freed
> 
> with u_long type start i get it:
> Mar 24 03:41:47 localhost kernel: Trying to free nonexistent resource 
> <00000000fffff000-00000000ffffffff>
> 
> investigating further...
> -

hmm well i dont get the free warning cause 

                        release_mem_region(ahc->platform_data->mem_busaddr,
                                           0x1000);
isnt called, the hack fails 

        error = ahc_linux_pci_reserve_mem_region(ahc, &base, &maddr);
        if (error == 0) {

ok, so no bounds issue in the driver.