Re: [PATCH 4.4 07/40] arm64: ensure __dump_instr() checks addr_limit

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, Nov 20, 2017 at 11:26:20AM +0000, Mark Rutland wrote:
> On Sun, Nov 19, 2017 at 11:29:35AM +0100, Greg Kroah-Hartman wrote:
> > On Tue, Nov 14, 2017 at 04:18:23PM +0000, Mark Rutland wrote:
> > > I agree that we need both patches. On its own (in the absence of PAN/UAO),
> > > 57f4959bad0a154a wouldn't have any effect, but it is critical to ensure that we
> > > can dump kernel instructions when we intend to, with 7a7003b1da010d2b
> > > backported.
> > > 
> > > Backporting 57f4959bad0a154a as a prerequisite makes sense to me.
> > 
> > But that is a "new feature", are you sure about this?
> 
> Sorry, I copied the wrong commit ID when replying. I meant to say that
> we should backport commit:
> 
>   c5cea06be060f38e ("arm64: fix dump_instr when PAN and UAO are in use")
> 
> ... which on its own does nothing, but will prevent 7a7003b1da010d2b
> from breaking kernel dumps.
> 
> We should *not* backport commit:
> 
>  57f4959bad0a154a ("arm64: kernel: Add support for User Access Override")
> 
> > So, just apply that one patch and we are all ok?  Nothing else?
> 
> Just apply c5cea06be060f38e as a prerequisite for 7a7003b1da010d2b, and
> I think we're good. I'm not aware of anything else we need.
> 
> > confused,
> 
> Sorry about that. Hopefully the above clarified things?

Yes, it did, thanks, I think I've queued up the right patches now, if
not, please let me know :)

greg k-h