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From: Andrew Morton <akpm@linux-foundation.org>
To: Ruihan Li <lrh2000@pku.edu.cn>
Cc: Mike Rapoport <rppt@kernel.org>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] mm/mm_init: Don't iterate pages below ARCH_PFN_OFFSET
Date: Sun, 20 Apr 2025 13:57:09 -0700	[thread overview]
Message-ID: <20250420135709.732883ee775ad8b41fb668ca@linux-foundation.org> (raw)
In-Reply-To: <20250419122801.1752234-1-lrh2000@pku.edu.cn>

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?


  reply	other threads:[~2025-04-20 20:57 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-19 12:28 Ruihan Li
2025-04-20 20:57 ` Andrew Morton [this message]
2025-04-21  9:35   ` Ruihan Li
2025-04-21 16:35   ` Mike Rapoport
2025-04-21 18:26     ` Andrew Morton
2025-04-21 16:41 ` Mike Rapoport
2025-04-22  9:08   ` Ruihan Li
2025-04-22 20:20     ` Andrew Morton
2025-04-22 20:25       ` David Woodhouse

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