EFI from usb HDD
Michal Simek
michal.simek at xilinx.com
Fri Jul 30 08:22:18 CEST 2021
On 7/30/21 7:33 AM, AKASHI Takahiro wrote:
> On Fri, Jul 30, 2021 at 06:41:01AM +0200, Michal Simek wrote:
>>
>>
>> On 7/30/21 4:35 AM, AKASHI Takahiro wrote:
>>> On Thu, Jul 29, 2021 at 04:09:32PM +0200, Michal Simek wrote:
>>>> Hi,
>>>>
>>>> On 6/10/21 2:59 PM, AKASHI Takahiro wrote:
>>>>> On Thu, Jun 10, 2021 at 02:31:46PM +0200, Michal Simek wrote:
>>>>>>
>>>>>>
>>>>>> On 6/10/21 12:51 PM, Heinrich Schuchardt wrote:
>>>>>>> On 6/10/21 12:04 PM, Michal Simek wrote:
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> On 6/10/21 11:47 AM, Heinrich Schuchardt wrote:
>>>>>>>>> On 6/10/21 10:44 AM, Michal Simek wrote:
>>>>>>>>>> Hi,
>>>>>>>>>>
>>>>>>>>>> I am playing with booting from USB via EFI. And I see very weird
>>>>>>>>>> behavior. I have burnt image with grub to USB flashdisk and I have
>>>>>>>>>> tested it on 3 zynqmp boards. zcu102, zcu104 and SOM Kria board.
>>>>>>>>>> On zcu102 grub is going to boot menu and everything is working fine as
>>>>>>>>>> expected.
>>>>>>>>>> On zcu104 and SOM Kria I am able to get grub not to menu. When I list
>>>>>>>>>> partitions in grub I see that only SDs are listed:
>>>>>>>>>> grub> ls
>>>>>>>>>> (hd0) (hd0,msdos1) (hd1) (hd1,msdos1)
>>>>>>>>>
>>>>>>>>> Hello Michal,
>>>>>>>>>
>>>>>>>>> thanks for sharing your observations.
>>>>>>>>>
>>>>>>>>> What devices do hd0 and hd1 relate to?
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On zcu102(working board) I also see usb(gpt) partitions and SD.
>>>>>>>>>> grub> ls
>>>>>>>>>> (hd0) (hd0,gpt2) (hd0,gpt1) (hd1) (hd1,msdos1)
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> GPT and MBR partitioning are independent of the device type.
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On zcu104 I see one more error message
>>>>>>>>>> "PE image measurement failed"
>>>>>>>>>
>>>>>>>>> This is related to CONFIG_EFI_TCG2_PROTOCOL=y. Do you have a TPMv2? This
>>>>>>>>> will not stop disk enumeration.
>>>>>>>>>
>>>>>>>>>> But I can't see it on SOM.
>>>>>>>>>>
>>>>>>>>>> U-Boot image is just the same for all boards. I am using generic
>>>>>>>>>> xilinx_zynqmp_virt_defconfig.
>>>>>>>>>>
>>>>>>>>>> When I compare DT description for USB between zcu102 and zcu104 they
>>>>>>>>>> are
>>>>>>>>>> the same. SOM doesn't have usb enabled by default (but I enabled it)
>>>>>>>>>> but
>>>>>>>>>> grub starts which means that communication with USB is fine.
>>>>>>>>>>
>>>>>>>>>> It is based on my latest patches available here.
>>>>>>>>>> u-boot/custodians/u-boot-microblaze.git (usb-efi-issue branch)
>>>>>>>>>>
>>>>>>>>>> Also when I list usb I see all partitions just fine.
>>>>>>>>>> ZynqMP> part list usb 0
>>>>>>>>>>
>>>>>>>>>> Partition Map for USB device 0 -- Partition Type: EFI
>>>>>>>>>>
>>>>>>>>>> Part Start LBA End LBA Name
>>>>>>>>>> Attributes
>>>>>>>>>> Type GUID
>>>>>>>>>> Partition GUID
>>>>>>>>>> 1 0x00000800 0x001007fe "Microsoft basic data"
>>>>>>>>>> attrs: 0x0000000000000000
>>>>>>>>>> type: ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
>>>>>>>>>> type: data
>>>>>>>>>> guid: 0e7f8b3d-296b-4720-be9d-c4687d3c4a77
>>>>>>>>>> 2 0x00100800 0x001197fe "Microsoft basic data"
>>>>>>>>>> attrs: 0x0000000000000000
>>>>>>>>>> type: ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
>>>>>>>>>> type: data
>>>>>>>>>> guid: 8892eddc-231a-4e6e-a5e1-c310f4482fb7
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Do you have any idea why on one system is working fine to get to menu
>>>>>>>>>> and on others there is an issue to get all partitions even u-boot is
>>>>>>>>>> able to see them and can work with them.
>>>>>>>>>>
>>>>>>>>>> Thanks,
>>>>>>>>>> Michal
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Where is the GRUB binary? - If it is in EFI/boot/bootaa64.efi, it could
>>>>>>>>> be that the USB sub-system is simply not initialized yet when the boot
>>>>>>>>> manager is called by distroboot.
>>>>>>>>>
>>>>>>>>> For testing partition detection in the UEFI sub-system it is enough
>>>>>>>>> to run
>>>>>>>>>
>>>>>>>>> efidebug devices
>>>>>>>>>
>>>>>>>>> Until yesterday we had a problem with partition numbers >= 10, cf.
>>>>>>>>>
>>>>>>>>> efi_loader: partition numbers are hexadecimal
>>>>>>>>> https://source.denx.de/u-boot/u-boot/-/commit/3dca77b1dc1b6dbf9c8b51572fe4b0553cef009f
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Block devices are enumerated in efi_disk_register(). Please, try to add
>>>>>>>>> debug output there to elucidate the problem.
>>>>>>>>
>>>>>>>> I found where the problem is. First of all zcu102 didn't use the same
>>>>>>>> image as others (it wasn't updated properly).
>>>>>>>> When you have CONFIG_EFI_CAPSULE_ON_DISK_EARLY that efi_disk_register()
>>>>>>>> is called before usb block devices are detected and registered that's
>>>>>>>> why grub doesn't see them.
>>>>>>>
>>>>>>> The problem is CONFIG_EFI_SETUP_EARLY=y required by
>>>>>>> CONFIG_EFI_CAPSULE_ON_DISK_EARLY.
>>>>>>>
>>>>>>> Why is USB initialized later then MMC?
>>>>>>
>>>>>> It is not just usb. SCSI/sata are behaving in the same way too.
>>>>>>
>>>>>>>
>>>>>>> Overall we have a deficiency in the UEFI implementation in that we
>>>>>>> cannot deal with block devices added or removed after initialization.
>>>>>>>
>>>>>>> Here integration with the driver model is missing.
>>>>>>
>>>>>> Right. And also there are commands which can create MBR partitions and I
>>>>>> expect when you write image to SD and then run rescan or so you could
>>>>>> get other partitions too.
>>>>>> Maybe hook via part_init()? with removing efi_disk_register.
>>>>>
>>>>> For the record, I have proposed my ideas several times[1], [2].
>>>>> I'm, however, no longer working on this issue as I have shifted
>>>>> my focus to UEFI secure boot and capsule update.
>>>>>
>>>>> -Takahiro Akashi
>>>>>
>>>>> [1] https://lists.denx.de/pipermail/u-boot/2018-November/347491.html
>>>>> [2] https://lists.denx.de/pipermail/u-boot/2019-February/357923.html
>>>>
>>>> I want to continue on this thread. I have disabled
>>>> EFI_CAPSULE_ON_DISK_EARLY some time ago and trying to workaround that
>>>> usb/scsi detection by simply calling usb reset and scsi reset as the
>>>> part of PREBOOT. Then all disks are recorded and visible by grub.
>>>>
>>>> But I found another issue which is kind of weird. We are using
>>>> distroboot with soft of fixed sequence. Important part of sequence is
>>>> sd, usb, scsi.
>>>>
>>>> I have added grub on scsi and when I boot directly via run bootcmd_scsi0
>>>> everything is working fine. When I let distroboot to do the job it or
>>>> run printenv -e before bootcmd_scsi0 I am getting exception.
>>>> From debug it is visible that it is exception called from
>>>> efi_disk_read_blocks.
>>>>
>>>> 0 0x7ff5d188 hang()+20: include/bootstage.h, line 389
>>>> 1 0x7ff5f908 __assert_fail(): lib/panic.c, line 25
>>>> 2 0x7fe976a8 do_irq(): arch/arm/lib/interrupts_64.c, line 123
>>>> 3 0x7fe96a0c _restore_regs()+124: arch/arm/cpu/armv8/exceptions.S,
>>>> line 141
>>>> 4 0x7ff43740 efi_disk_read_blocks()+160: lib/efi_loader/efi_disk.c,
>>>> line 102
>>>
>>> How and when did you get this stack trace?
>>
>> When Abort happened I connected Xilinx debugger via jtag and look at cpu
>> backtrace.
>
> OK, but we are already in grub here and such a trace (in U-Boot)
> doesn't make sense. Right?
Correct grub already started. But I expect it is still using U-Boot
drivers and all exception handlers are still in place from u-boot.
Maybe it is just sata/scsi related issue in EFI but weird is that when
disks are scan just before command everything is working fine.
Should I try to initialize and populate EFI object list all the time?
(Remove this code for testing)
/* Initialize once only */
if (efi_obj_list_initialized != OBJ_LIST_NOT_INITIALIZED)
return efi_obj_list_initialized;
Or based on this thread to try your series pointed above?
Thanks,
Michal
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