Hi,
On 2/2/2023 12:35 AM, Song Liu wrote:
> On Mon, Jan 30, 2023 at 10:39 PM Hou Tao <houtao@xxxxxxxxxxxxxxx> wrote:
>> From: Hou Tao <houtao1@xxxxxxxxxx>
>>
>> Don't update recovery_cp when curr_resync is MD_RESYNC_ACTIVE, otherwise
>> md may skip the resync of the first 3 sectors if the resync procedure is
>> interrupted before the first calling of ->sync_request() as shown below:
>>
>> md_do_sync thread control thread
>> // setup resync
>> mddev->recovery_cp = 0
>> j = 0
>> mddev->curr_resync = MD_RESYNC_ACTIVE
>>
>> // e.g., set array as idle
>> set_bit(MD_RECOVERY_INTR, &&mddev_recovery)
>> // resync loop
>> // check INTR before calling sync_request
>> !test_bit(MD_RECOVERY_INTR, &mddev->recovery
>>
>> // resync interrupted
>> // update recovery_cp from 0 to 3
>> // the resync of three 3 sectors will be skipped
>> mddev->recovery_cp = 3
>>
>> Fixes: eac58d08d493 ("md: Use enum for overloaded magic numbers used by mddev->curr_resync")
>> Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
> By the way, how did you find this issue? Is it from users/production?
> Or just from reading the code?
Found the issue when reading the code and reproduced the problem to confirm that.
>
> Thanks,
> Song
