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Subject[PATCH] 2/6 i386 serialize-msr
i386 arch cleanup.  Introduce the serialize macro to serialize processor state.
Why the microcode update needs it I am not quite sure, since wrmsr() is already
a serializing instruction, but it is a microcode update, so I will keep the
semantic the same, since this could be a timing workaround. As far as I can
tell, this has always been there since the original microcode update source.

Signed-off-by: Zachary Amsden <zach@vmware.com>

Index: linux-2.6.13/arch/i386/kernel/microcode.c
===================================================================
--- linux-2.6.13.orig/arch/i386/kernel/microcode.c 2005-07-29 11:14:33.000000000 -0700
+++ linux-2.6.13/arch/i386/kernel/microcode.c 2005-07-29 11:16:18.000000000 -0700
@@ -164,7 +164,8 @@
}

wrmsr(MSR_IA32_UCODE_REV, 0, 0);
- __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
+ /* XXX needed? wrmsr should serialize unless a chip bug */
+ serialize();
/* get the current revision from MSR 0x8B */
rdmsr(MSR_IA32_UCODE_REV, val[0], uci->rev);
pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
@@ -377,7 +378,9 @@
(unsigned long) uci->mc->bits >> 16 >> 16);
wrmsr(MSR_IA32_UCODE_REV, 0, 0);

- __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
+ /* XXX needed? wrmsr should serialize unless a chip bug */
+ serialize();
+
/* get the current revision from MSR 0x8B */
rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);

Index: linux-2.6.13/include/asm-i386/processor.h
===================================================================
--- linux-2.6.13.orig/include/asm-i386/processor.h 2005-07-29 11:16:10.000000000 -0700
+++ linux-2.6.13/include/asm-i386/processor.h 2005-07-29 11:16:28.000000000 -0700
@@ -277,6 +277,11 @@
outb((data), 0x23); \
} while (0)

+static inline void serialize(void)
+{
+ __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
+}
+
static inline void __monitor(const void *eax, unsigned long ecx,
unsigned long edx)
{
-
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