Lenovo N24 / USB NIC with ASIX AX88772C chip
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@bloodwar Just to make sure we are on the right track I want you to test this
08_bzImagekernel booted as EFI binary straight from a USB key. For that get an empty USB key, format with FAT32/VFAT, create directory strctureBOOT/EFIand copy/rename the kernel image file into that directory so it ends up asEFI/BOOT/BOOTX64.EFI. Can be done on Windows or Linux, doesn’t matter.Unmount/eject the USB key and boot from that on your client. Please take a picture and post here so we can compare the debug message traces.
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results
https://i.imgur.com/sx54w5G.jpg -
@bloodwar Great, thanks again for testing. So it’s clear this is not an iPXE issue at all but just a crapy UEFI firmware implementation causing this hang (even if you simply boot the Linux kernel in UEFI mode).
At the stage were things seem to go wrong I see the following comment in the kernel code:
/* * The memory map changed between efi_get_memory_map() and * exit_boot_services(). Per the UEFI Spec v2.6, Section 6.4: * EFI_BOOT_SERVICES.ExitBootServices we need to get the * updated map, and try again. The spec implies one retry * should be sufficent, which is confirmed against the EDK2 * implementation. Per the spec, we can only invoke * get_memory_map() and exit_boot_services() - we cannot alloc * so efi_get_memory_map() cannot be used, and we must reuse * the buffer. For all practical purposes, the headroom in the * buffer should account for any changes in the map so the call * to get_memory_map() is expected to succeed here. */So the kernel is kind of aware of UEFI implementations that toss with the memory map but unfortunately there seems to be special ones that do even more magic. I’ll try to figure out more about this but I guess it will be very hard to find. Although I have done a fair bit of kernel hacking I am not at all a kernel dev or even close to it. So it’s more or less guessing, trying and reading that I can do.
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@bloodwar I just uploaded
09_bzImagefor you to test. It skips part of the code that I think could be causing the issue on your device. Let’s see what happens. Try it and post a picture again. -
used the usb nic instead of usb boot.
https://i.imgur.com/RSFHzB9.jpg -
@bloodwar Ok?!? This is interesting. Shows that I don’t have a clue what the Lenovo N24 UEFI firmware is doing here. So just commenting some code doesn’t help.
Searching the web for whatever I found a post where syslinux people are talking about this as well - http://www.syslinux.org/archives/2015-September/024212.html - The implementation proposed here is trying at least twice so I think this is a bit different to how the Linux kernel is handling it at the moment. I’ll try to implement that and let you know.
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@bloodwar Ok here we go, please give
10_bzImagea try… -
no go… but i feel like your getting closer to it lol
https://i.imgur.com/NQg48i5.jpg -
@bloodwar
11_bzImagewill try 10 times. Don’t think this helps but it’s easy to test. -
11 results https://i.imgur.com/9b0WwQb.jpg
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@bloodwar If we can’t make it work this way yet I’d suggest trying a different combination like GRUB + Linux kernel. For that please download
usb.img(same download link - 64 MB), get an empty USB key and dump that image to USB like this:dd bs=1M if=/tmp/usb.img of=/dev/sdXMake sure you have the correct device filename - could be
/dev/sdbor/dev/sdc… After connecting the USB key to your machine wait 5 seconds for it to settle and the rundmesg | tailto see which device name it has.If you only have a Windows machine at hand you can also use Win32DiskImager to write that image to your USB key.
Then boot your Lenovo N24 of that USB key and see what happens. It has GRUB debug enabled and should loop at that stop where we seem to have a problem on “exit_boot_services”. Though I am not sure this will help. It’s just a test to see if you can boot the kernel straight from a GRUB USB key.
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used Win32DiskImager
usb booted
selected “fog official kernel - /boot/bzimage” and “fog debug kernel - /boot/11_bzimage”same results on both
https://i.imgur.com/I5uPXH3.jpg -
@bloodwar Ok, I forgot to add one parameter and therefore it fails. But booting essentially works. Could you please take a video of the start sequence between the point where you hit ENTER after selecting one of the two kernels and where the kernel messages scroll past. I’d like to see the GRUB debug messages! You could even just take a picture of it if you know exactly which debug messages I mean. On the screen it should say something like
loader/i386/linux.c .... -
i think this is it… first thing that pops up after you select fog default kernel.
https://i.imgur.com/tw5mYSl.jpg
if not i’ll take a video of it -
@bloodwar Please plug the USB key back into a running (Windows) machine and edit the file
boot\grub2\grub.cfgand add,mmapto line number 6, so it looks like this:set myimage=/boot/bzImage set mydbgimage=/boot/11_bzImage set myinit=/boot/init.xz set myloglevel=7 set pager=1 set debug=linux,mmap set timeout=-1 insmod all_video ...Boot from that USB key again - now you need to skip through the pages as there are many messages on screen… Best if you can take a steady video of all this.
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https://i.imgur.com/LXbIQfu.jpg
seems to be endless if i hold enter
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@bloodwar Yeah, but there are the debug messages from the last picture you took somewhere in between. I’d like to see exactly that screen as picture. Things like
real_mode_target ...andreal_mode_mem ...should be on there. -
i’ll try and get a better video… what i have for now
https://youtu.be/e7tUmhpUPMY -
@bloodwar The video is pretty good, though it’s not with the
mmapdebug enabled. -
Alright tried booting it up again. Held the spacebar till any actually information showed up. Problem is it scrolls way to quickly to record anything. Are therre any log files i can create/capture to show what it’s doing?