Re: [Xen-devel] [PATCH MM-PART2 RESEND v2 19/19] xen/arm: Pair call to set_fixmap with call to clear_fixmap in copy_from_paddr

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Tue, 4 Jun 2019, Julien Grall wrote:
> On 6/4/19 6:59 PM, Stefano Stabellini wrote:
> > On Tue, 14 May 2019, Julien Grall wrote:
> > > At the moment, set_fixmap may replace a valid entry without following
> > > the break-before-make sequence. This may result to TLB conflict abort.
> > > 
> > > Rather than dealing with Break-Before-Make in set_fixmap, every call to
> > > set_fixmap is paired with a call to clear_fixmap.
> > 
> > It is not every call to set_fixmap: it is every call to
> > set_fixmap(FIXMAP_MISC, ...
> 
> I don't understand this request... The title explicit mention
> "copy_from_paddr" and fixmap is only called with FIXMAP_MISC.
> 
> So why should I need to specify the argument?

I wasn't asking to mention FIXMAP_MISC explicitely, I don't think it is
particularly useful. I was only trying to make the wording more
specific to what the patch does.

The statement "every call to set_fixmap is paired with a call to
clear_fixmap" is too generic and I would prefer if it was limited in
scope by something like

  "in copy_from_paddr"

Like you have done in the subject. Resulting in:
  
  every call to set_fixmap in copy_from_paddr is paired with a call to
  clear_fixmap


> > Please clarify, then you can add
> > 
> > Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel