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charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/4/26 07:51, Oscar Salvador (SUSE) wrote: > On Mon, Jun 01, 2026 at 01:25:12PM -0700, Dave Hansen wrote: >> Oscar, even if the real fix involves a couple of patches, can we please >> see that, first? Then, we can go back and make an informed decision >> about hacks versus proper fixes. > Fix sits here [1]. > It is quite straightforward, is arch-agnostic and I can confirm it fixes > the AMD regression. > It is part of a 8-patch series [2] (#1 is the fix and follow up are > cleanups). So it does appear that the x86 workaround wasn't the best direction. That patch looks fine. I find it a bit hard to parse. I'd probably say something more along the lines of: /* * hugetlb mappings need to be huge page aligned. * mm_get_unmapped_area_vmflags() only gives back PAGE_SIZE * aligned areas. * * Extend the requested unmapped area for the worse case * scenario: the address comes back and needs to be aligned * up by one small page short of a large page. */ len += huge_page_size(h) - PAGE_SIZE; Also, wouldn't it be more clear to just talk about the length in terms of page sizes, not masks? Also, do you even need this if()? if (addr0 & ~huge_page_mask(h)) So the code looks like this: pgoff = 0; addr0 = mm_get_unmapped_area_vmflags(file, addr0,... /* Align the address to the next huge_page_size boundary */ addr0 = ALIGN(addr0, huge_page_size(h)); If it's aligned, it won't do anything. But I'm 100% ok with the approach. I *believe* the code you have is OK, although I'm not feeling super confident that I've read the mask calculations correctly. So while I'd like some improvements, I'm OK with this: Acked-by: Dave Hansen