[PATCH] x86-64: Fix bad assumption that dualcore cpus have synced TSCs

[john stultz <johnstul@us.ibm.com>]

Andrew,
	This patch should resolve the issue seen in bugme bug #5105, where it
is assumed that dualcore x86_64 systems have synced TSCs. This is not
the case, and alternate timesources should be used instead.

For more details, see:
http://bugzilla.kernel.org/show_bug.cgi?id=5105


Please consider for inclusion in your tree.

thanks
-john

diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -959,9 +959,6 @@ static __init int unsynchronized_tsc(voi
  	   are handled in the OEM check above. */
  	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
  		return 0;
- 	/* All in a single socket - should be synchronized */
- 	if (cpus_weight(cpu_core_map[0]) == num_online_cpus())
- 		return 0;
 #endif
  	/* Assume multi socket systems are not synchronized */
  	return num_online_cpus() > 1;


-
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