On 15/03/2023 15:38, Kirill A. Shutemov wrote:
On Wed, Mar 15, 2023 at 03:35:23PM +0000, Tvrtko Ursulin wrote:
On 15/03/2023 15:28, Kirill A. Shutemov wrote:
On Wed, Mar 15, 2023 at 02:18:52PM +0000, Tvrtko Ursulin wrote:
On 15/03/2023 11:31, Kirill A. Shutemov wrote:
MAX_ORDER is not inclusive: the maximum allocation order buddy allocator
can deliver is MAX_ORDER-1.
This looks to be true on inspection:
__alloc_pages():
..
if (WARN_ON_ONCE_GFP(order >= MAX_ORDER, gfp))
So a bit of a misleading name "max".. For the i915 patch:
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
I don't however see the whole series to understand the context, or how you
want to handle the individual patches. Is it a tree wide cleanup of the same
mistake?
The whole patchset can be seen here:
https://lore.kernel.org/all/20230315113133.11326-1-kirill.shutemov@xxxxxxxxxxxxxxx/
The idea is to fix all MAX_ORDER bugs first and then re-define MAX_ORDER
more sensibly.
Sounds good.
Would you like i915 to take this patch or you will be bringing the whole lot
via some other route? Former is okay and latter should also be fine for i915
since I don't envisage any conflicts here.
I think would be better to get it via mm tree.
Ack for that. But as I saw that by the end of the series you also change
this back as you redefine MAX_ORDER to be inclusive you could even
simplify things and just not do anything for i915. I am pretty sure we
never call this helper for > 4M allocations otherwise we would have seen
this warn.
Regards,
Tvrtko
