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authorLinus Torvalds <torvalds@woody.osdl.org>2006-12-07 08:59:11 -0800
committerLinus Torvalds <torvalds@woody.osdl.org>2006-12-07 08:59:11 -0800
commit4522d58275f124105819723e24e912c8e5bf3cdd (patch)
treeb92c29014fadffe049c1925676037f0092b8d112 /arch/i386/kernel/alternative.c
parent6cf24f031bc97cb5a7c9df3b6e73c45b628b2b28 (diff)
parent64a26a731235b59c9d73bbe82c1f896d57400d37 (diff)
Merge branch 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6
* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (156 commits) [PATCH] x86-64: Export smp_call_function_single [PATCH] i386: Clean up smp_tune_scheduling() [PATCH] unwinder: move .eh_frame to RODATA [PATCH] unwinder: fully support linker generated .eh_frame_hdr section [PATCH] x86-64: don't use set_irq_regs() [PATCH] x86-64: check vector in setup_ioapic_dest to verify if need setup_IO_APIC_irq [PATCH] x86-64: Make ix86 default to HIGHMEM4G instead of NOHIGHMEM [PATCH] i386: replace kmalloc+memset with kzalloc [PATCH] x86-64: remove remaining pc98 code [PATCH] x86-64: remove unused variable [PATCH] x86-64: Fix constraints in atomic_add_return() [PATCH] x86-64: fix asm constraints in i386 atomic_add_return [PATCH] x86-64: Correct documentation for bzImage protocol v2.05 [PATCH] x86-64: replace kmalloc+memset with kzalloc in MTRR code [PATCH] x86-64: Fix numaq build error [PATCH] x86-64: include/asm-x86_64/cpufeature.h isn't a userspace header [PATCH] unwinder: Add debugging output to the Dwarf2 unwinder [PATCH] x86-64: Clarify error message in GART code [PATCH] x86-64: Fix interrupt race in idle callback (3rd try) [PATCH] x86-64: Remove unwind stack pointer alignment forcing again ... Fixed conflict in include/linux/uaccess.h manually Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/i386/kernel/alternative.c')
-rw-r--r--arch/i386/kernel/alternative.c63
1 files changed, 52 insertions, 11 deletions
diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c
index 535f9794fba..9eca21b49f6 100644
--- a/arch/i386/kernel/alternative.c
+++ b/arch/i386/kernel/alternative.c
@@ -124,6 +124,20 @@ static unsigned char** find_nop_table(void)
#endif /* CONFIG_X86_64 */
+static void nop_out(void *insns, unsigned int len)
+{
+ unsigned char **noptable = find_nop_table();
+
+ while (len > 0) {
+ unsigned int noplen = len;
+ if (noplen > ASM_NOP_MAX)
+ noplen = ASM_NOP_MAX;
+ memcpy(insns, noptable[noplen], noplen);
+ insns += noplen;
+ len -= noplen;
+ }
+}
+
extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
extern struct alt_instr __smp_alt_instructions[], __smp_alt_instructions_end[];
extern u8 *__smp_locks[], *__smp_locks_end[];
@@ -138,10 +152,9 @@ extern u8 __smp_alt_begin[], __smp_alt_end[];
void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
{
- unsigned char **noptable = find_nop_table();
struct alt_instr *a;
u8 *instr;
- int diff, i, k;
+ int diff;
DPRINTK("%s: alt table %p -> %p\n", __FUNCTION__, start, end);
for (a = start; a < end; a++) {
@@ -159,13 +172,7 @@ void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
#endif
memcpy(instr, a->replacement, a->replacementlen);
diff = a->instrlen - a->replacementlen;
- /* Pad the rest with nops */
- for (i = a->replacementlen; diff > 0; diff -= k, i += k) {
- k = diff;
- if (k > ASM_NOP_MAX)
- k = ASM_NOP_MAX;
- memcpy(a->instr + i, noptable[k], k);
- }
+ nop_out(instr + a->replacementlen, diff);
}
}
@@ -209,7 +216,6 @@ static void alternatives_smp_lock(u8 **start, u8 **end, u8 *text, u8 *text_end)
static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end)
{
- unsigned char **noptable = find_nop_table();
u8 **ptr;
for (ptr = start; ptr < end; ptr++) {
@@ -217,7 +223,7 @@ static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end
continue;
if (*ptr > text_end)
continue;
- **ptr = noptable[1][0];
+ nop_out(*ptr, 1);
};
}
@@ -343,6 +349,40 @@ void alternatives_smp_switch(int smp)
#endif
+#ifdef CONFIG_PARAVIRT
+void apply_paravirt(struct paravirt_patch *start, struct paravirt_patch *end)
+{
+ struct paravirt_patch *p;
+
+ for (p = start; p < end; p++) {
+ unsigned int used;
+
+ used = paravirt_ops.patch(p->instrtype, p->clobbers, p->instr,
+ p->len);
+#ifdef CONFIG_DEBUG_PARAVIRT
+ {
+ int i;
+ /* Deliberately clobber regs using "not %reg" to find bugs. */
+ for (i = 0; i < 3; i++) {
+ if (p->len - used >= 2 && (p->clobbers & (1 << i))) {
+ memcpy(p->instr + used, "\xf7\xd0", 2);
+ p->instr[used+1] |= i;
+ used += 2;
+ }
+ }
+ }
+#endif
+ /* Pad the rest with nops */
+ nop_out(p->instr + used, p->len - used);
+ }
+
+ /* Sync to be conservative, in case we patched following instructions */
+ sync_core();
+}
+extern struct paravirt_patch __start_parainstructions[],
+ __stop_parainstructions[];
+#endif /* CONFIG_PARAVIRT */
+
void __init alternative_instructions(void)
{
unsigned long flags;
@@ -390,5 +430,6 @@ void __init alternative_instructions(void)
alternatives_smp_switch(0);
}
#endif
+ apply_paravirt(__start_parainstructions, __stop_parainstructions);
local_irq_restore(flags);
}