<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type"> <title></title> </head> <body bgcolor="#ffffff" text="#000000"> jonathan barkelew wrote: <blockquote cite="mid9B4771B4D9FB73498B40311D4E7E8EE502D5947B@atl-ms2.us.megatrends.com" type="cite"> <meta http-equiv="Content-Type" content="text/html; "> <meta name="Generator" content="MS Exchange Server version 6.5.7651.59"> <title>UEFI Compatibility Issues in Fedora 10</title>  The second issue is far more pressing, and much more difficult to solve. The linux kernel will behave incorrectly if more than 400k of runtime memory is declared by system firmware. The kernel attempts to map all UEFI runtime memory into the kernel fixmap table, and any requests to map more than 400k are silently ignored. If this memory is accessed later in the boot process (after transition to virtual mode), the kernel will panic. It is my understanding that this mechanism was designed to enable kexec functionality, but this mechanism is UEFI non-compliant. If Fedora is ever to be reliably booted on UEFI systems, this issue must be addressed. </blockquote> I had gotten this fixed upstream, committed in the 2.6.29-rc8 kernel. efi_ioremap was broken. This should also be in the latest rawhide kernel. Perhaps you can verify the problem is resolved? If it is not resolved, please let me know. <blockquote cite="mid9B4771B4D9FB73498B40311D4E7E8EE502D5947B@atl-ms2.us.megatrends.com" type="cite"> I've briefly contacted the LKML, but after very little discussion the issue was forgotten. I personally don't know how to solve the runtime boot problem while still enabling kexec, but it was my hope that if the Fedora community were involved a solution might be found. </blockquote> I had not tested the efi_ioremap fixes with kexec. I would appreciate testing feedback if you have any (test with kernel >= 2.6.29-rc8) Brian </body> </html>