Booting from ROM crashes after ipxe.iso runs with timeout

[farpoint]

A certain boot sequence always results in system crashes or freezes. In my case I was using E1000 network card with QEMU emulator and KVM. The guest was trying to boot with empty hard disk and CD-ROM image of ipxe.iso. The problem happens when DHCP server is not yet ready (or it does not provide boot file, etc.), so that after timeout, the BIOS falls back to ROM boot (which happens to be pxe-e1000.rom file in QEMU project) and there it crashes after displaying this message:

IPXE (PCI xx:xx:x) starting execution...

This crash apparently does not happen in two other cases:

1. Booting from ipxe.iso image when no rom image is supplied (i.e. pxe-e1000.rom file is missing or is not installed).
2. Booting without ipxe.iso image and with pxe-e1000.rom present.

In my opinion, running ipxe.iso code renders ROM boot unusable and results in guest code eventually to jump to code which looks like long sequence of zeroes.

In addition to the said above, I've previously seen some posts on the net complaining about crashes with pxe-e1000.rom and QEMU/KVM. Also, as additional information, I was using the most recent version of ipxe sources and different versions of QEMU (old and new ones) to verify that.

I'm not familiar well with this project. Any thoughts or (better) quick fixes would be welcome. A quick workaround would be like this : if using CDROM image, hide the pxe-e1000.rom file (and don't hide it when no CDROM image is given).

Thank you.

[NiKiZe]

Have this been discussed with the Qemu people?

is both ipxe.iso and the pxe-e1000.rom built from latest ipxe git or are you using pxe-e1000.rom that comes with Qemu?

[farpoint]

The issue is first posted here, it hasn't been discussed elsewhere. The problem happens with the latest ipxe.iso and pxe-e1000.rom built from the project, it also happens with pxe ROMs which are supplied as part of QEMU. It also happens with older versions of ipxe.iso images. From my recent attempt to debug the issue, the crash happens inside install_prealloc function, somewhere nearby the code displaying progress of ".text16.late".

The problem manifests itself only when ipxe.iso runs first, timeouts and eventually the boot loader runs the pxe rom code. Without ipxe.iso or when pxe rom is not found, no crashes were observed : the system reboots as expected and the cycle is repeated.

[Venca]

Hello together,
I have similar problem, so I decided to use this thread.
I am using Award BIOS with Davicom network controller. I generated rom file and I included this ROM to the BIOS itself via cbrom. But when I am trying to perform PXE boot I always stuck at romprefix.s "exec" function(?probably - I did not debug?). Last message showned on the screen is:
"iPXE (PCI 00:13.0) starting execution..." and nothing happened.

I tried normal build and bin-x86_64-pcbios option. I also tried to exclude all not necessary option to have rom file smaller that 65kB.
Ineresting is that gPXE(version 1.0.1) works in the correct way, but I fails on latest iPXE.

Please, do you have any idea what could be wrong? I probably did some stupid mistake or forget somethink important.

Thank you very much in advance.

Best regards,
Vaclav

[NiKiZe]

(2016-11-28 17:38)Venca Wrote:  Hello together,
I have similar problem, so I decided to use this thread.
I am using Award BIOS with Davicom network controller. I generated rom file and I included this ROM to the BIOS itself via cbrom. But when I am trying to perform PXE boot I always stuck at romprefix.s "exec" function(?probably - I did not debug?). Last message showned on the screen is:
"iPXE (PCI 00:13.0) starting execution..." and nothing happened.

I tried normal build and bin-x86_64-pcbios option. I also tried to exclude all not necessary option to have rom file smaller that 65kB.
Ineresting is that gPXE(version 1.0.1) works in the correct way, but I fails on latest iPXE.

Please, do you have any idea what could be wrong? I probably did some stupid mistake or forget somethink important.

Thank you very much in advance.

Best regards,
Vaclav

first of, does ipxe.usb work from usb?
What are the exact build command you tried? Have you tried that the exact same but with .usb instead of .rom works?

How big (in bytes) is the gpxe.rom that you have tried, and how big is the ipxe.rom that you have tried?