reed solomon breaks larger pxe images

[Seth Goldberg]

Hi,

  While trying to test pxe booting, I noticed that creating a pxe image larger 
than around 100k causes the system hard-hang after control is transferred to 
pxegrub.  I narrowed it down to an unknown problem in 
grub_reed_solomon_recover (called from startup.S).  Unconditionally jumping 
over the call allows the system to continue to proceed to the menu.  So, if 
you're trying to build a pxe image with a lot of modules, and you get a hard 
hang, try this:

=== modified file 'grub-core/kern/i386/pc/startup.S'
--- grub-core/kern/i386/pc/startup.S    2010-12-24 06:29:28 +0000
+++ grub-core/kern/i386/pc/startup.S    2010-12-27 04:26:25 +0000
@@ -147,6 +147,8 @@
        incl    %eax
        call    grub_gate_a20

+       jmp post_reed_solomon
+
        movl    EXT_C(grub_compressed_size), %edx
        addl    $(GRUB_KERNEL_MACHINE_RAW_SIZE - 
GRUB_KERNEL_I386_PC_NO_REED_SOLOMON_PART), %edx
        movl    reed_solomon_redundancy, %ecx



 --S