From: Rusty Russell Date: Tue, 26 Sep 2006 08:52:39 +0000 (+0200) Subject: [PATCH] i386: Allow a kernel not to be in ring 0 X-Git-Tag: v2.6.19-rc1~1077^2~41 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=78be3706b21a232310590fe00258b224177ac05f;p=pandora-kernel.git [PATCH] i386: Allow a kernel not to be in ring 0 We allow for the fact that the guest kernel may not run in ring 0. This requires some abstraction in a few places when setting %cs or checking privilege level (user vs kernel). This is Chris' [RFC PATCH 15/33] move segment checks to subarch, except rather than using #define USER_MODE_MASK which depends on a config option, we use Zach's more flexible approach of assuming ring 3 == userspace. I also used "get_kernel_rpl()" over "get_kernel_cs()" because I think it reads better in the code... 1) Remove the hardcoded 3 and introduce #define SEGMENT_RPL_MASK 3 2) Add a get_kernel_rpl() macro, and don't assume it's zero. And: Clean up of patch for letting kernel run other than ring 0: a. Add some comments about the SEGMENT_IS_*_CODE() macros. b. Add a USER_RPL macro. (Code was comparing a value to a mask in some places and to the magic number 3 in other places.) c. Add macros for table indicator field and use them. d. Change the entry.S tests for LDT stack segment to use the macros Signed-off-by: Rusty Russell Signed-off-by: Zachary Amsden Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Andrew Morton Signed-off-by: Andi Kleen --- Reading git-diff-tree failed