That was probably incorrect usage of ddrescue :(
Here's more accurate output from
dd if=/dev/sda count=1 bs=512 skip=976773167


Do you know how to read it or it's just to make sure that it's gpt header?

On Wed, Sep 16, 2015 at 7:46 PM, Andrei Borzenkov <[email protected]>
wrote:

> 16.09.2015 10:04, Vyacheslav Gonakhchyan пишет:
>
> I boot using option "usb". It goes into grub rescue mode. Maybe it reads
>> devices from grubx64.efi. Other boot options "arch", "Test" don't work and
>> give me black screen with blinking cursor.
>>
>> efibootmgr -v
>> BootCurrent: 0002
>> Timeout: 3 seconds
>> BootOrder: 0008,0006,0003,0001,0000,0004,0005,0002
>> Boot0000* CD/DVD Drive    BBS(CDROM,,0x0)
>> Boot0001* Hard Drive    BBS(HD,,0x0)
>> Boot0002* usb
>> PciRoot(0x0)/Pci(0x12,0x2)/USB(5,0)/USB(1,0)/File(\EFI\arch\grubx64.efi)
>> Boot0003* Test
>>
>> HD(7,GPT,c92e4c3a-00d8-41cf-81f4-3d3c5a8e86aa,0x3a282000,0x104000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)
>> Boot0004* UEFI: FAT File System
>> PciRoot(0x0)/Pci(0x12,0x2)/USB(5,0)/USB(1,0)
>> Boot0005* Removable Drive    BBS(Floppy,,0x0)SPCC USB Flash Memory1.00.
>> Boot0006* arch
>>
>> HD(7,GPT,c92e4c3a-00d8-41cf-81f4-3d3c5a8e86aa,0x3a282000,0x104000)/File(\EFI\arch\grubx64.efi)
>> Boot0008* Windows Boot Manager
>>
>> HD(7,GPT,c92e4c3a-00d8-41cf-81f4-3d3c5a8e86aa,0x3a282000,0x104000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}....................
>>
>> is disk 512b or 4K?
>>>
>> cat /sys/block/sda/queue/hw_sector_size prints 512
>>
>> Attached output from
>> dd if=/dev/sda count=1 bs=1024 of=~/sda_1k.out
>> ddrescue  --reverse  --size=512 /dev/sda ~/sda_last.out
>>
>>
> Are you sure it actually saves the last sector? File you attached looks
> identical to the very first sector. If it is indeed the last one, it may
> confuse firmware (last sector must contain copy of GPT header but GRUB
> never checked it).
>
> Otherwise header looks fine. I assume partition table itself should be OK
> as both grub and Linux accept it.
>
>
>
>>
>> On Wed, Sep 16, 2015 at 6:24 AM, Andrei Borzenkov <[email protected]>
>> wrote:
>>
>> 15.09.2015 22:40, Vyacheslav Gonakhchyan пишет:
>>>
>>> map -v
>>>>
>>>>>
>>>>> Mapping table
>>>>         FS0: Alias(s):F7f0b0:;BLK5:
>>>>             PciRoot(0x0)/Pci(0x12,0x2)/USB(0x5,0x0)/USB(0x1,0x0)
>>>>            Handle:      [C5]
>>>>            Media Type:  Unknown
>>>>            Removable:   Yes
>>>>            Current Dir: FS0:
>>>>        BLK0: Alias(s):
>>>>             PciRoot(0x0)/Pci(0x11,0x0)/Sata(0x0,0x0)
>>>>            Handle:      [CC]
>>>>            Media Type:  Unknown
>>>>            Removable:   No
>>>>            Current Dir: BLK0:
>>>>        BLK2: Alias(s):
>>>>             PciRoot(0x0)/Pci(0x11,0x0)/Sata(0x1,0x0)
>>>>            Handle:      [CD]
>>>>            Media Type:  Unknown
>>>>            Removable:   No
>>>>            Current Dir: BLK2:
>>>>        BLK4: Alias(s):
>>>>             PciRoot(0x0)/Pci(0x11,0x0)/Sata(0x2,0x0)
>>>>            Handle:      [CE]
>>>>            Media Type:  Unknown
>>>>            Removable:   No
>>>>            Current Dir: BLK4:
>>>>        BLK1: Alias(s):
>>>>
>>>>
>>>>
>>>> PciRoot(0x0)/Pci(0x11,0x0)/Sata(0x0,0x0)/HD(1,MBR,0x91E11F57,0x1,0x3A38602F)
>>>>            Handle:      [CF]
>>>>            Media Type:  HardDisk
>>>>            Removable:   No
>>>>            Current Dir: BLK1:
>>>>        BLK3: Alias(s):
>>>>
>>>>
>>>>
>>>> PciRoot(0x0)/Pci(0x11,0x0)/Sata(0x1,0x0)/HD(1,MBR,0x00040B8F,0x3F,0x74705982)
>>>>            Handle:      [D0]
>>>>            Media Type:  HardDisk
>>>>            Removable:   No
>>>>            Current Dir: BLK3:
>>>>
>>>> So everything is bad because my MB(ASUS *M5A97*) suddenly cannot
>>>> discover
>>>> gpt partitions?
>>>>
>>>>
>>> This explains GRUB behavior. But now I'm extremely confused - can your
>>> system actually boot? Where does it boot from? Could you show "efibootmgr
>>> -v" output?
>>>
>>> I have not said it in first mail but this boot situation
>>>
>>>> started after I tried to resize one partition in Acronis Disk Director
>>>> 12
>>>> and it failed. Maybe it did something to gpt tables. But archlinux can
>>>> work
>>>> with them so it's strange.
>>>>
>>>>
>>>> So does GRUB. Could you attach the first 1K and the last sector from
>>> this
>>> disk? And, BTW, is disk 512b or 4K?
>>>
>>>
>>> On Tue, Sep 15, 2015 at 1:14 PM, Andrei Borzenkov <[email protected]>
>>>
>>>> wrote:
>>>>
>>>> On Tue, Sep 15, 2015 at 12:28 PM, Vyacheslav Gonakhchyan
>>>>
>>>>> <[email protected]> wrote:
>>>>>
>>>>> Attached devtree output. Don't have serial console so provided image
>>>>>>
>>>>>> links.
>>>>>
>>>>>
>>>>>> Do you see entry corresponding to hd1,gpt7?
>>>>>>
>>>>>>>
>>>>>>> Only HD entries I see:
>>>>>> http://postimg.org/image/5a5n8yylv/
>>>>>> Entire lsefi output:
>>>>>> http://postimg.org/gallery/206hl6qfo/fcc52503/?code=fcc52503
>>>>>>
>>>>>>
>>>>>> ls -l output:
>>>>>> http://postimg.org/image/ntoj0d7lf/
>>>>>> http://postimg.org/image/666q25xo3/
>>>>>>
>>>>>>
>>>>>> Well, you firmware sees two partitions - (hd2,msdos2) and what is
>>>>> probably protective MBR on hd1. It does *NOT* show any trace of GPT
>>>>> partitions on hd1.
>>>>>
>>>>> Could you please boot EFI Shell and attach output of "map -v" command?
>>>>>
>>>>> On Tue, Sep 15, 2015 at 6:56 AM, Andrei Borzenkov <[email protected]
>>>>> >
>>>>>
>>>>>> wrote:
>>>>>>
>>>>>>
>>>>>>> 15.09.2015 01:18, Vyacheslav Gonakhchyan пишет:
>>>>>>>
>>>>>>>
>>>>>>>> I installed grub-git and efibootmgr-git and reproduced it.
>>>>>>>> If it matters could not build efivar-git so it's few month behind.
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Could you please run "lsefi" in GRUB CLI and look for paths ending
>>>>>>> with
>>>>>>> HD(...). It is structured as
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>> HD(<partition_number>,<partition_start>,<partition_size>,<partition_signature>,<partmap_type>,<signature_type>)
>>>>>
>>>>>
>>>>>> Do you see entry corresponding to hd1,gpt7?
>>>>>>>
>>>>>>> Unless you have serial console you want to do
>>>>>>>
>>>>>>> set pager=1
>>>>>>>
>>>>>>> otherwise it will scroll too fast. Keep in mind that there is no way
>>>>>>> to
>>>>>>> abort output once started you will have to keep paging it until end.
>>>>>>> If
>>>>>>>
>>>>>>> you
>>>>>>
>>>>>
>>>>> have serial console, could you attach output as well as "ls -l"?
>>>>>>
>>>>>>>
>>>>>>> Could you also boot EFI Shell and attach output of "devtree" (you can
>>>>>>> redirect to a file on ESP).
>>>>>>>
>>>>>>>
>>>>>>> On Mon, Sep 14, 2015 at 7:42 PM, Andrei Borzenkov <
>>>>>>> [email protected]
>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>> wrote:
>>>>>>
>>>>>>>
>>>>>>>> 14.09.2015 15:36, Vyacheslav Gonakhchyan пишет:
>>>>>>>>
>>>>>>>>>
>>>>>>>>> My Grub2 is EFI. I use grub-install --target=x86_64-efi
>>>>>>>>>
>>>>>>>>>> --efi-directory=/boot/efi /dev/sda which calls efibootmgr to load
>>>>>>>>>> grubx64.efi into UEFI BIOS.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> OK in this case message means that grub cannot find EFI handle for
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> $root
>>>>>>>>
>>>>>>>
>>>>> (i.e. in your case - partition gpt7). GRUB itself needs just disk
>>>>>>
>>>>>>> reference
>>>>>>>>> and handles partitions internally. But when launching external
>>>>>>>>> binary
>>>>>>>>>
>>>>>>>>> it
>>>>>>>>
>>>>>>>
>>>>> wants to pass it reference to device where it is located which means
>>>>>>
>>>>>>>
>>>>>>>>> it
>>>>>>>>
>>>>>>>
>>>>> must be exported and accessible by firmware.
>>>>>>
>>>>>>>
>>>>>>>>> The first step would be to try to reproduce it using upstream
>>>>>>>>> sources.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> echo $grub_cpu $grub_platform
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>> Sorry, can only check it later. I'm guessing x86_64, efi-64...
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On Mon, Sep 14, 2015 at 4:11 PM, Andrei Borzenkov <
>>>>>>>>>>
>>>>>>>>>> [email protected]>
>>>>>>>>>
>>>>>>>>
>>>>> wrote:
>>>>>>
>>>>>>>
>>>>>>>>>> On Mon, Sep 14, 2015 at 2:36 PM, Vyacheslav Gonakhchyan
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>> <[email protected]> wrote:
>>>>>>>>>>>
>>>>>>>>>>> Hi, everyone!
>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> I have dual boot config Archlinux/Windows7 and latest packages.
>>>>>>>>>>>> I
>>>>>>>>>>>>
>>>>>>>>>>>> am
>>>>>>>>>>>
>>>>>>>>>>
>>>>>
>>>>>> booted
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> into grub rescue mode. Or use command line. I want to tell Grub2
>>>>>>>>>>> to
>>>>>>>>>>>
>>>>>>>>>>>> load
>>>>>>>>>>>> Windows Boot Loader bootmgfw.efi. Basically grub2 refuses to do
>>>>>>>>>>>> it
>>>>>>>>>>>> with
>>>>>>>>>>>> error "invalid root device".
>>>>>>>>>>>>
>>>>>>>>>>>> Steps to reproduce:
>>>>>>>>>>>>
>>>>>>>>>>>> set root=(hd1,gpt7)
>>>>>>>>>>>>
>>>>>>>>>>>>> chainloader /EFI/Microsoft/Boot/bootmgfw.efi
>>>>>>>>>>>>>
>>>>>>>>>>>>> Screen is flashing with "invalid root device".
>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Is your grub BIOS or EFI? What are values for grub_cpu and
>>>>>>>>>>>>
>>>>>>>>>>> grub_platform?
>>>>>>>>>>>
>>>>>>>>>>> echo $grub_cpu $grub_platform
>>>>>>>>>>>
>>>>>>>>>>> So grub2 finds bootmgfw.efi but cannot give it control. I tried
>>>>>>>>>>>
>>>>>>>>>>> every
>>>>>>>>>>
>>>>>>>>>
>>>>>
>>>>>>
>>>>>>>>>>>> other
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> hd1,gpt combination to no avail.  I also tried setting root to
>>>>>>>>>>> one
>>>>>>>>>>>
>>>>>>>>>>>> device
>>>>>>>>>>>> and loading bootmgfw.efi from another device(hd1,gpt7).
>>>>>>>>>>>> It's strange because I can load this file from shell
>>>>>>>>>>>> (shellx64.efi)
>>>>>>>>>>>>
>>>>>>>>>>>> within
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> UEFI BIOS without error. Any advice is appreciated.
>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Regards,
>>>>>>>>>>>> Viacheslav
>>>>>>>>>>>>
>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>> Help-grub mailing list
>>>>>>>>>>>> [email protected]
>>>>>>>>>>>> https://lists.gnu.org/mailman/listinfo/help-grub
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>

Attachment: sda_last_512.out
Description: Binary data

_______________________________________________
Help-grub mailing list
[email protected]
https://lists.gnu.org/mailman/listinfo/help-grub

Reply via email to