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From: Song Liu <song@kernel.org>
Date: Mon, 29 Jan 2024 23:11:18 -0800
Message-ID: <CAPhsuW7y32Mw+PmvnLg-o=ZS22ZOuzLd19zDHix3qA93_X8SGA@mail.gmail.com>
Subject: Re: [PATCH] md: use RCU lock to protect traversal in md_spares_need_change()
To: Li Lingfeng <lilingfeng@huaweicloud.com>
Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, 
	yukuai3@huawei.com, yukuai1@huaweicloud.com, linan122@huawei.com, 
	yi.zhang@huawei.com, yangerkun@huawei.com, lilingfeng3@huawei.com
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On Thu, Jan 4, 2024 at 5:39=E2=80=AFAM Li Lingfeng <lilingfeng@huaweicloud.=
com> wrote:
>
> From: Li Lingfeng <lilingfeng3@huawei.com>
>
> Since md_start_sync() will be called without the protect of mddev_lock,
> and it can run concurrently with array reconfiguration, traversal of rdev
> in it should be protected by RCU lock.
> Commit bc08041b32ab ("md: suspend array in md_start_sync() if array need
> reconfiguration") added md_spares_need_change() to md_start_sync(),
> casusing use of rdev without any protection.
> Fix this by adding RCU lock in md_spares_need_change().
>
> Fixes: bc08041b32ab ("md: suspend array in md_start_sync() if array need =
reconfiguration")
> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>

Looks good to me. Applied to md-tmp-6.9.

Thanks,
Song