Re: [PATCH] net-tg3: Initialize REG_BASE_ADDR at PCI config offset120 to 0

From: Natarajan Gurumoorthy
Date: Mon Dec 09 2013 - 14:22:56 EST


Michael,
We had crashes when the PCI config space got scanned via
/sys/devices/pcixxxx/....../config.

I agree that this fix will not help if the scan happens before the tg3
driver gets loaded.

Regards
Nat

On Mon, Dec 9, 2013 at 11:00 AM, Michael Chan <mchan@xxxxxxxxxxxx> wrote:
> On Mon, 2013-12-09 at 10:43 -0800, Nat Gurumoorthy wrote:
>> The new tg3 driver leaves REG_BASE_ADDR (PCI config offset 120)
>> uninitialized. From power on reset this register may have garbage in it. The
>> Register Base Address register defines the device local address of a
>> register. The data pointed to by this location is read or written using
>> the Register Data register (PCI config offset 128). When REG_BASE_ADDR has
>> garbage any read or write of Register Data Register (PCI 128) will cause the
>> PCI bus to lock up. The TCO watchdog will fire and bring down the system.
>>
>>
> Is this to prevent problem from other software that may be scanning the
> PCI config space? It won't help if this happens before the tg3 driver
> is loaded, right?
>
> Thanks.
>



--
Regards
Nat Gurumoorthy AB6SJ
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