Re: Booting from NVMe controller enters GRUB rescue

[Andrey Borzenkov]

On Fri, Jan 10, 2014 at 3:48 PM, vinayak holikatti
<address@hidden> wrote:
> On Fri, Jan 10, 2014 at 1:47 PM, Andrey Borzenkov <address@hidden> wrote:
>> On Fri, Jan 10, 2014 at 10:53 AM, vinayak holikatti
>> <address@hidden> wrote:
>>> Hi All,
>>>
>>> We have developed Legacy OptionROM for NVMe controller device. We are
>>> able to boot to all Windows 7 and later OS. But we are facing issue in
>>> booting Fedora 20 x86_64 OS. Fedora 20 gets installed successfully on
>>> NVMe device. While booting from NVMe device we are observing error as
>>> follows and enters grub rescue. We are clueless about what is
>>> happening here. We would like to know how to over come this issue and
>>> boot to Fedora 20 OS from our controller.
>>>
>>> "error : no such device: 44d1bf09-4e8a-4f46-aea6-09e364abf5cb.
>>>  Entering rescue mode...
>>>  grub_rescue>"
>>>
>>
>> GRUB cannot find filesystem with UUID printed. Some of required
>> drivers are missing in core.img. What is NVMe? Could you give more
>> information (is it BIOS compatible? Are you using HDD or some other
>> media? What is disk layout - any MD, LVM or other RAID partitions?)
>
> Hi Andrey,
>
> We have taken a log of Bootinfo script as below. Non Volatile Memory
> Express(NVMe) is PCIe based
> controller. In Linux kernel for this controller there is a driver
> module present with name nvme.ko. We will
> start looking at core.img. There is no BIOS support for this device as
> it is a PCIe plug and play
> device. We have our Legacy OptionROM support for booting from this controller.
>

Does this Legacy OptionROM emulate BIOS disk access? I.e. is this
device visible as HDD in BIOS?

On BIOS platform GRUB is using biosdisk module; it relies on BIOS disk
calls (INT 13). I think I remember cases when it was not completely
implemented by option ROMs.