From: "David Hildenbrand (arm)" <david@kernel.org>
To: Ingyu Jang <ingyujang25@korea.ac.kr>, linux-mm@kvack.org
Cc: akpm@linux-foundation.org
Subject: Re: [Question] Dead code in copy_pud_range() for copy_huge_pud() error check?
Date: Mon, 2 Feb 2026 16:40:54 +0100 [thread overview]
Message-ID: <f2014bf5-a4d7-489c-acf3-3a3339c030bd@kernel.org> (raw)
In-Reply-To: <20260131172854.3370590-1-ingyujang25@korea.ac.kr>
On 1/31/26 18:28, Ingyu Jang wrote:
> Hi,
>
> I noticed that in mm/memory.c, the function copy_pud_range() checks
> if copy_huge_pud() returns -ENOMEM (at line 1421):
>
> err = copy_huge_pud(dst_mm, src_mm,
> dst_pud, src_pud, addr, src_vma);
> if (err == -ENOMEM)
> return -ENOMEM;
>
> However, looking at copy_huge_pud() in mm/huge_memory.c (line 1966),
> it only returns two values:
> - 0 on success (line 1994)
> - -EAGAIN when !pud_trans_huge(pud) (line 1978)
>
I think it cannot currently trigger, but likely would once we support
PUD THP, see [1]. So best to leave it as is.
[1] https://lkml.kernel.org/r/20260202005451.774496-1-usamaarif642@gmail.com
--
Cheers
David
prev parent reply other threads:[~2026-02-02 15:41 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-31 17:28 Ingyu Jang
2026-02-02 15:28 ` Joshua Hahn
2026-02-02 15:37 ` Matthew Wilcox
2026-02-02 15:50 ` Joshua Hahn
2026-02-02 15:40 ` David Hildenbrand (arm) [this message]
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