Re: [PATCH] [RFC] fix kernel crash (protection id trap) when

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sun, 2008-12-21 at 17:20 -0500, Kyle McMartin wrote:
> On Sun, Dec 21, 2008 at 10:20:16AM -0500, John David Anglin wrote:
> > > Honestly, I can't decide whether to apply this. It really should never
> > > happen in the kernel, since the kernel can guarantee it won't get the
> > > access rights failure (highest privilege level, and can set %sr and
> > > %protid to whatever it wants.)
> > 
> > I believe this change should be applied because we enable P and the
> > hardware can generate the exception.  Yes, it should never happen, but
> > the coding to prevent this occurring is very subtle.
> > 
> 
> If we're going to paper over a bug like this, we might as well just turn
> the P-bit off...

I'm afraid you can't.  The invisibility of the kernel space from user
space relies on this, as does quite a lot of the page protections.

James


--
To unsubscribe from this list: send the line "unsubscribe linux-parisc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux SoC]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux