Re: [PATCH v2] mm/mm_init: Don't iterate pages below ARCH_PFN_OFFSET

[Mike Rapoport <rppt@kernel.org>]

On Sun, Apr 20, 2025 at 01:57:09PM -0700, Andrew Morton wrote:
> On Sat, 19 Apr 2025 20:28:01 +0800 Ruihan Li <lrh2000@pku.edu.cn> wrote:
> 
> > If ARCH_PFN_OFFSET is very large (e.g., something like 2^64-2GiB if the
> > kernel is used as a library and loaded at a very high address), the
> > pointless iteration for pages below ARCH_PFN_OFFSET will take a very
> > long time, and the kernel will look stuck at boot time.
> > 
> > This commit sets the initial value of pfn_hole to ARCH_PFN_OFFSET, which
> > avoids the problematic and useless iteration mentioned above.
> > 
> > This problem has existed since commit 907ec5fca3dc ("mm: zero remaining
> > unavailable struct pages").
> > 
> > Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn>
> > ---
> > Link to v1:
> >  - https://lore.kernel.org/linux-mm/20250418162727.1535335-1-lrh2000@pku.edu.cn/
> > Changes since v1:
> >  - Removed the unnecessary Fixes tag.
> 
> Why was the Fixes: considered unnecessary?  It seems to be useful
> information?

I didn't think it was important enough for AUTOSEL to pick it. 

-- 
Sincerely yours,
Mike.