Re: [PATCH v9 4/5] md: add check_new_feature module parameter

[Li Nan]

在 2025/11/4 9:47, Xiao Ni 写道:
> On Mon, Nov 3, 2025 at 9:06 PM <linan666@xxxxxxxxxxxxxxx> wrote:
> > From: Li Nan <linan122@xxxxxxxxxx>
> >
> > Raid checks if pad3 is zero when loading superblock from disk. Arrays
> > created with new features may fail to assemble on old kernels as pad3
> > is used.
> >
> > Add module parameter check_new_feature to bypass this check.
> >
> > Signed-off-by: Li Nan <linan122@xxxxxxxxxx>
>
> Hi
>
> Thanks for finding this problem in time. The default of this kernel
> module is true. I don't think people can check new kernel modules
> after updating to a new kernel. They will find the array can't
> assemble and report bugs. You already use pad3, is it good to remove
> the check about pad3 directly here?
>
> By the way, have you run the regression tests?

Sorry for missing this reply earlier. I ran mdadm tests and tested new
RAID on old kernels with check_new_feature both on and off. All passed.

> Regards
> Xiao
>
>
> .

--
Thanks,
Nan