Re: [PATCH v2 3/4] md/raid10: fix wrong setting of max_corr_read_errors

[Li Nan]

在 2023/5/13 10:21, Yu Kuai 写道:
> Hi,
>
> 在 2023/05/13 9:08, Song Liu 写道:
> > On Fri, May 5, 2023 at 7:02 PM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
> > > Hi,
> > >
> > > 在 2023/05/06 9:23, linan666@xxxxxxxxxxxxxxx 写道:
> > > > From: Li Nan <linan122@xxxxxxxxxx>
> > > >
> > > > max_corr_read_errors should not be negative number. Change it to
> > > > unsigned int where use it.
> > >
> > > Looks good, feel free to add:
> > >
> > > Reviewed-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> > >
> > > > Fixes: 1e50915fe0bb ("raid: improve MD/raid10 handling of 
> > > > correctable read errors.")
> > > > Signed-off-by: Li Nan <linan122@xxxxxxxxxx>
> >
> > Hmm.. Does the current code break in any cases?
>
> The problem is that somewhere use unsigned value, and somewhere use
> signed value, and I thinsk the only functional change is in
> fix_read_error(), if max_read_errors is negative, the judgement will
> always pass before this patch:
>
> if (atomic_read(&rdev->read_errors) > max_read_errors)

In addition, it is confusing for users after setting a huge number to it.
  # echo 4294967295 > /sys/block/$disk/md/max_read_errors
  # cat /sys/block/$disk/md/max_read_errors
    -1

--
Thanks,
Nan