Peter Wemm bf1e897425 Give a %fs and %gs to userland. Use swapgs to obtain the kernel %GS.base ... value on entry and exit. This isn't as easy as it sounds because when we recursively trap or interrupt, we have to avoid duplicating the swapgs instruction or we end up back with the userland %gs. I implemented this by testing TF_CS to see if we're coming from supervisor mode already, and check for returning to supervisor. To avoid a race with interrupts in the brief period after beginning executing the handler and before the swapgs, convert all trap gates to interrupt gates, and reenable interrupts immediately after the swapgs. I am not happy with this. There are other possible ways to do this that should be investigated. (eg: storing the GS.base MSR value in the trapframe) Add some sysarch functions to let the userland code get to this. Approved by: re (blanket amd64/*)		2003-05-12 02:37:29 +00:00
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acpica	Commit MD parts of a loosely functional AMD64 port. This is based on	2003-05-01 01:05:25 +00:00
amd64	Give a %fs and %gs to userland. Use swapgs to obtain the kernel %GS.base	2003-05-12 02:37:29 +00:00
compile	Make space for compilations.	2002-07-06 02:49:07 +00:00
conf	Turn syscons on now that it works, so that anybody trying to run this	2003-05-09 18:26:06 +00:00
ia32	Regen.	2003-04-25 15:59:44 +00:00
include	Give a %fs and %gs to userland. Use swapgs to obtain the kernel %GS.base	2003-05-12 02:37:29 +00:00
isa	Give a %fs and %gs to userland. Use swapgs to obtain the kernel %GS.base	2003-05-12 02:37:29 +00:00
pci	Commit MD parts of a loosely functional AMD64 port. This is based on	2003-05-01 01:05:25 +00:00
Makefile	This commit adds basic support for the UFS2 filesystem. The UFS2	2002-06-21 06:18:05 +00:00