From: Andrew Morton <akpm@linux-foundation.org>
To: Muchun Song <songmuchun@bytedance.com>
Cc: mike.kravetz@oracle.com, muchun.song@linux.dev,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: hugetlb_vmemmap: fix a race between vmemmap pmd split
Date: Fri, 7 Jul 2023 12:38:44 -0700 [thread overview]
Message-ID: <20230707123844.adf56ba3e0d000f6da431494@linux-foundation.org> (raw)
In-Reply-To: <20230707033859.16148-1-songmuchun@bytedance.com>
On Fri, 7 Jul 2023 11:38:59 +0800 Muchun Song <songmuchun@bytedance.com> wrote:
> The local variable @page in __split_vmemmap_huge_pmd() to obtain a pmd
> page without holding page_table_lock may possiblely get the page table
> page instead of a huge pmd page. The effect may be in set_pte_at()
> since we may pass an invalid page struct, if set_pte_at() wants to
> access the page struct (e.g. CONFIG_PAGE_TABLE_CHECK is enabled), it
> may crash the kernel. So fix it. And inline __split_vmemmap_huge_pmd()
> since it only has one user.
Is this likely enough to justify a backport?
I'm thinking "add cc:stable and merge into 6.6-rc1", so it hits -stable
after a couple of months of testing.
next prev parent reply other threads:[~2023-07-07 19:38 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-07 3:38 Muchun Song
2023-07-07 19:38 ` Andrew Morton [this message]
2023-07-08 1:42 ` Muchun Song
2023-07-09 0:46 ` Andrew Morton
2023-07-07 19:41 ` Andrew Morton
2023-07-08 1:40 ` Muchun Song
2023-08-14 22:28 ` Mike Kravetz
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