Re: [PATCH v3] disk/mdraid1x: Fix >2TB RAID detection with BIOS

[Robert LeBlanc]

On Wed, Jan 25, 2017 at 3:02 PM, Robert LeBlanc <address@hidden> wrote:
> Changes in v3:
>   - Fix to return if not out of range instead of breaking out of the
>     loop.
>
> Changes in v2:
>   - Only continue checking for other metadata versions if we get an out
>     of range error and reset grub_errno if we continue.
>
> When a mdadm RAID array is on a drive larger than 2TB, the array is not
> able to be detected and as such even if the array has a partition that
> holds /boot under the 2TB limit, it is unable to boot the machine. This
> is caused by metadata 1.0 being tested first which allocates the
> superblock at the end of the device. When it tries to access the end of
> the device it throws an error and the code returns without trying to
> find the superblock at other locations (metadata 1.1 and 1.2). This
> patch changes the error to not be fatal and allow for the checking for
> the other metadata versions and allowing the machine to boot as long as
> /boot is under the 2TB BIOS limit. This won't cause issues with 1.0
> metadata because GRUB is able to read the partitions from the front of
> the drive/partition without having to determine the data offset, since
> the data for metadata 1.0 starts at sector 0.
>
> Signed-off-by: Robert LeBlanc <address@hidden>
> ---
>  grub-core/disk/mdraid1x_linux.c | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/grub-core/disk/mdraid1x_linux.c b/grub-core/disk/mdraid1x_linux.c
> index 7cc80d3df..f0aeb6829 100644
> --- a/grub-core/disk/mdraid1x_linux.c
> +++ b/grub-core/disk/mdraid1x_linux.c
> @@ -148,7 +148,17 @@ grub_mdraid_detect (grub_disk_t disk,
>
>        if (grub_disk_read (disk, sector, 0, sizeof (struct 
> grub_raid_super_1x),
>                           &sb))
> -       return NULL;
> +       {
> +         if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
> +           {
> +             grub_errno = GRUB_ERR_NONE;
> +             continue;
> +           }
> +          else
> +           {
> +             return NULL;
> +           }
> +       }
>
>        if (sb.magic != grub_cpu_to_le32_compile_time (SB_MAGIC)
>           || grub_le_to_cpu64 (sb.super_offset) != sector)
> --
> 2.11.0
>

Vladimir,

Does this patch resolve your concerns?
----------------
Robert LeBlanc
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