Re: [Xen-devel] Re: [RFC, PATCH 5/24] i386 Vmi code patching

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


Anthony Liguori wrote:
Chris Wright wrote:
* Andi Kleen ([email protected]) wrote:
The disassembly stuff indeed doesn't look like something
that belongs in the kernel.
Strongly agreed.  The strict ABI requirements put forth here are not
in-line with Linux, IMO.  I think source compatibility is the limit of
reasonable, and any ROM code be in-tree if something like this were to
be viable upstream.
Hi Chris,

Would you have less trouble if the "ROM" were actually more like a module? Specifically, if it had a proper elf header and symbol table, used symbols as entry points, and was a GPL interface (so that ROM's had to be GPL)? Then it's just a kernel module that's hidden in the option ROM space and has a C interface.
I know you end up losing the ability to do crazy inlining of the ROM
code but I think it becomes a much less hairy interface that way.
Actually, I think you still can get the ability to do crazy inlining of
the ROM code. You have three exports from the ELF module:
vmi_init - enter paravirtual mode
vmi_annotate - apply inline transformations based on inlining
vmi_exit - exit paravirtual mode (required for module unloading).

But you can't require the ROM to be GPL'd. It has to be multi-licensed for compatibility with other open source or, even proprietary operating systems. If the ROM is licensed for use only under the GPL, then by including it in your kernel and allowing it to patch your kernel code, you leave your non-GPL kernel in a questionable license state. If the ROM is licensed under an open license, with a clause allowing its inclusion into GPL'd software, then I don't think you have a problem. Course I could be wrong. This is sort of a unique situation, and finding an identical comparison is tricky.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at
Please read the FAQ at

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux