Re: [Xen-devel] [PATCH 2/3] xen: actually skip the first MAX_ORDER bits in pfn_pdx_hole_setup

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Mon, 6 May 2019, Jan Beulich wrote:
> >>> On 03.05.19 at 22:50, <sstabellini@xxxxxxxxxx> wrote:
> > Fix the issue by passing j+1 and i+1 to find_next_zero_bit and
> > find_next_bit. Also add a check for i >= BITS_PER_LONG because
> > find_{,next_}zero_bit() on x86 assume their last argument to be less
> > than their middle one.
> 
> I had pointed out x86 since I knew it has this assumption. Now
> that you mention it here, I would have expected you've checked
> that Arm doesn't make similar assumptions. 32-bit Arm looks to
> do, though (while 64-bit has a dedicated if() to deal with the
> situation).

I think that either way we want to say that those functions are not
supposed to be called that way. I'll update the commit message.

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