Zachary Amsden f2f30ebca6 [PATCH] x86: introduce a write acessor for updating the current LDT ... Introduce a write acessor for updating the current LDT. This is required for hypervisors like Xen that do not allow LDT pages to be directly written. Testing - here's a fun little LDT test that can be trivially modified to test limits as well. /* * Copyright (c) 2005, Zachary Amsden (zach@vmware.com) * This is licensed under the GPL. */ #include <stdio.h> #include <signal.h> #include <asm/ldt.h> #include <asm/segment.h> #include <sys/types.h> #include <unistd.h> #include <sys/mman.h> #define __KERNEL__ #include <asm/page.h> void main(void) { struct user_desc desc; char *code; unsigned long long tsc; code = (char *)mmap(0, 8192, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); desc.entry_number = 0; desc.base_addr = code; desc.limit = 1; desc.seg_32bit = 1; desc.contents = MODIFY_LDT_CONTENTS_CODE; desc.read_exec_only = 0; desc.limit_in_pages = 1; desc.seg_not_present = 0; desc.useable = 1; if (modify_ldt(1, &desc, sizeof(desc)) != 0) { perror("modify_ldt"); } printf("code base is 0x%08x\n", (unsigned)code); code[0x0ffe] = 0x0f; /* rdtsc */ code[0x0fff] = 0x31; code[0x1000] = 0xcb; /* lret */ __asm__ __volatile("lcall $7,$0xffe" : "=A" (tsc)); printf("TSC is 0x%016llx\n", tsc); } Signed-off-by: Zachary Amsden <zach@vmware.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>		2005-09-05 00:06:13 -07:00
..
boot	[PATCH] coverity: i386: build.c: negative return to unsigned fix	2005-06-28 21:20:33 -07:00
crypto	[PATCH] arch/i386/crypto/aes.c: fix sparse warnings	2005-06-25 16:24:59 -07:00
kernel	[PATCH] x86: introduce a write acessor for updating the current LDT	2005-09-05 00:06:13 -07:00
lib	[PATCH] Remove i386_ksyms.c, almost.	2005-06-23 09:45:11 -07:00
mach-default	[PATCH] x86_64: CPU hotplug support	2005-06-25 16:24:30 -07:00
mach-es7000	[PATCH] ES7000 platform update (i386)	2005-09-05 00:06:10 -07:00
mach-generic	[PATCH] x86: sutomatically enable bigsmp when we have more than 8 CPUs	2005-09-05 00:06:10 -07:00
mach-visws	[PATCH] visws: linkage fix	2005-08-07 10:00:38 -07:00
mach-voyager	[PATCH] x86: more asm cleanups	2005-09-05 00:06:12 -07:00
math-emu	[PATCH] i386: inline assembler: cleanup and encapsulate descriptor and task register management	2005-09-05 00:06:11 -07:00
mm	[PATCH] i386: use set_pte macros in a couple places where they were missing	2005-09-05 00:06:12 -07:00
oprofile	[PATCH] xen: x86: Rename usermode macro	2005-06-23 09:45:14 -07:00
pci	[PATCH] x86: pci_assign_unassigned_resources() update	2005-08-30 11:14:48 -07:00
power	[PATCH] x86: remove redundant TSS clearing	2005-09-05 00:06:13 -07:00
defconfig	[PATCH] swsusp: kill config_pm_disk	2005-06-25 16:24:32 -07:00
Kconfig	[PATCH] sparsemem extreme implementation	2005-09-05 00:05:38 -07:00
Kconfig.debug	[PATCH] i386: add missing Kconfig help text	2005-07-27 16:25:58 -07:00
Makefile	[PATCH] biarch compiler support for i386	2005-06-23 09:45:07 -07:00