From: Al Viro <viro@zeniv.linux.org.uk>
To: Zizhi Wo <wozizhi@huaweicloud.com>
Cc: jack@suse.com, brauner@kernel.org, hch@lst.de,
akpm@linux-foundation.org, linux@armlinux.org.uk,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org,
wozizhi@huawei.com, yangerkun@huawei.com,
wangkefeng.wang@huawei.com, pangliyuan1@huawei.com,
xieyuanbin1@huawei.com
Subject: Re: [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context
Date: Wed, 26 Nov 2025 18:55:45 +0000 [thread overview]
Message-ID: <20251126185545.GC3538@ZenIV> (raw)
In-Reply-To: <20251126090505.3057219-1-wozizhi@huaweicloud.com>
On Wed, Nov 26, 2025 at 05:05:05PM +0800, Zizhi Wo wrote:
> under an RCU read-side critical section. In linux-mainline, arm/arm64
> do_page_fault() still has this problem:
>
> lock_mm_and_find_vma->get_mmap_lock_carefully->mmap_read_lock_killable.
arm64 shouldn't hit do_page_fault() in the first place, and
do_translation_fault() there will see that address is beyond TASK_SIZE
and go straight to do_bad_area() -> __do_kernel_fault() -> fixup_exception(),
with no messing with mmap_lock.
Can anybody confirm that problem exists on arm64 (ideally - with
reproducer)?
next prev parent reply other threads:[~2025-11-26 18:55 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-26 9:05 [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context Zizhi Wo
2025-11-26 10:19 ` [RFC PATCH] vfs: Fix might sleep in load_unaligned_zeropad() with rcu read lock held Xie Yuanbin
2025-11-26 18:10 ` Al Viro
2025-11-26 18:48 ` Al Viro
2025-11-26 19:05 ` Russell King (Oracle)
2025-11-26 19:26 ` Al Viro
2025-11-26 19:51 ` Russell King (Oracle)
2025-11-26 20:02 ` Al Viro
2025-11-26 22:25 ` david laight
2025-11-26 23:51 ` Al Viro
2025-11-26 23:31 ` Russell King (Oracle)
2025-11-27 3:03 ` Xie Yuanbin
2025-11-27 7:20 ` Sebastian Andrzej Siewior
2025-11-27 11:20 ` Xie Yuanbin
2025-11-28 1:39 ` Xie Yuanbin
2025-11-26 20:42 ` Al Viro
2025-11-26 10:27 ` [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context Zizhi Wo
2025-11-26 21:12 ` Linus Torvalds
2025-11-27 10:27 ` Will Deacon
2025-11-27 10:57 ` Russell King (Oracle)
2025-11-28 17:06 ` Linus Torvalds
2025-11-29 1:01 ` Zizhi Wo
2025-11-29 1:35 ` Linus Torvalds
2025-11-29 4:08 ` [Bug report] hash_name() may cross page boundary and trigger Xie Yuanbin
2025-11-29 9:08 ` Al Viro
2025-11-29 9:25 ` Xie Yuanbin
2025-11-29 9:44 ` Al Viro
2025-11-29 10:05 ` Xie Yuanbin
2025-11-29 10:45 ` david laight
2025-11-29 8:54 ` [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context Al Viro
2025-12-01 2:08 ` Zizhi Wo
2025-11-29 2:18 ` [Bug report] hash_name() may cross page boundary and trigger Xie Yuanbin
2025-12-01 13:28 ` [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context Will Deacon
2025-12-02 12:43 ` Russell King (Oracle)
2025-12-02 13:02 ` Xie Yuanbin
2025-12-02 22:07 ` Linus Torvalds
2025-12-03 1:48 ` Xie Yuanbin
2025-12-05 12:08 ` Russell King (Oracle)
2025-12-08 2:32 ` Xie Yuanbin
2025-12-08 9:26 ` David Laight
2025-12-08 10:07 ` Russell King (Oracle)
2025-12-08 13:18 ` Xie Yuanbin
2025-12-08 15:43 ` Russell King (Oracle)
2025-12-09 1:30 ` Xie Yuanbin
2025-11-26 18:55 ` Al Viro [this message]
2025-11-27 2:24 ` Zizhi Wo
2025-11-29 3:37 ` Al Viro
2025-11-30 3:01 ` [RFC][alpha] saner vmalloc handling (was Re: [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context) Al Viro
2025-11-30 11:32 ` david laight
2025-11-30 16:43 ` Al Viro
2025-11-30 18:14 ` Magnus Lindholm
2025-11-30 19:03 ` david laight
2025-11-30 20:31 ` Al Viro
2025-11-30 20:32 ` Al Viro
2025-11-30 22:16 ` Linus Torvalds
2025-11-30 23:37 ` Al Viro
2025-12-01 2:03 ` [Bug report] hash_name() may cross page boundary and trigger sleep in RCU context Zizhi Wo
2025-11-27 12:59 ` Will Deacon
2025-11-28 1:17 ` Zizhi Wo
2025-11-28 1:18 ` Zizhi Wo
2025-11-28 1:39 ` Zizhi Wo
2025-11-28 12:25 ` Will Deacon
2025-11-29 1:02 ` Zizhi Wo
2025-11-29 3:55 ` Al Viro
2025-12-01 2:38 ` Zizhi Wo
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