kernel virtual memory access (from app) does not generatesegfault

[anfei.zhou@gmail.com (anfei)]

On Wed, Apr 21, 2010 at 12:17:41PM +0100, Dave P. Martin wrote:
>  
> 
> > -----Original Message-----
> > From: Russell King - ARM Linux [mailto:linux at arm.linux.org.uk] 
> > Sent: 20 April 2010 23:41
> > To: Jamie Lokier
> > Cc: Ben Dooks; anfei; Dave P Martin; 
> > linux-arm-kernel at lists.infradead.org
> > Subject: Re: kernel virtual memory access (from app) does not 
> > generatesegfault
> 
> [...]
> 
> > The difference between instruction faults and data faults is 
> > that we always interpret instruction faults on pre-ARMv6 CPUs 
> > as a 'translation fault' rather than a permission fault since 
> > they can't tell us what the problem was.
> 
> Note that my observations were on an armv7 kernel.  Should we still hit the
> same bit of code in this case, or have I misdiagnosed the problem?
> 
You said your kernel is .28, so it seems too old and this commit may fix
it: 
commit d25ef8b86e6a58f5476bf6e4a8da730b335f68fa
	ARM: 5728/1: Proper prefetch abort handling on ARMv6 and ARMv7

Cheers,
Anfei.

> Cheers
> ---Dave
> 
> 
>