[PATCH] oprofile: don't set counter width from cpuid on core2

[Tim Blechmann]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

resetting the counter width of the performance counters on intel's
core2, breaks the delivery of NMIs, when running in x86_64 mode.

this should fix bug #12395:
http://bugzilla.kernel.org/show_bug.cgi?id=12395

Signed-off-by: Tim Blechmann <tim@xxxxxxxxxx>
- ---
 arch/x86/oprofile/op_model_ppro.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/arch/x86/oprofile/op_model_ppro.c b/arch/x86/oprofile/op_model_ppro.c
index e9f80c7..ecba9f2 100644
- --- a/arch/x86/oprofile/op_model_ppro.c
+++ b/arch/x86/oprofile/op_model_ppro.c
@@ -78,10 +78,18 @@ static void ppro_setup_ctrs(struct op_msrs const * const msrs)
 	if (cpu_has_arch_perfmon) {
 		union cpuid10_eax eax;
 		eax.full = cpuid_eax(0xa);
+
+		/* For core2 (family 6, model 15), don't reset the counter width */
+		if (eax.split.version_id == 0 && current_cpu_data.x86 == 6 &&
+		      current_cpu_data.x86_model == 15)
+			goto clear_all_counters;
+
 		if (counter_width < eax.split.bit_width)
 			counter_width = eax.split.bit_width;
 	}
 
+clear_all_counters:
+
 	/* clear all counters */
 	for (i = 0 ; i < num_counters; ++i) {
 		if (unlikely(!CTRL_IS_RESERVED(msrs, i)))
- -- 
1.6.1.2
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAkmdifsACgkQdL+4qsZfVsu7uwCffznCNF7PKtaRw0Z28qy6PtO1
DP8AnjkSBNLvKGdG8ac90ayoO2L7GRjW
=xYgd
-----END PGP SIGNATURE-----
èº{.nÇ+?·?®?­?+%?Ëlzwm?éb?맲æìr¸?zX§»®w¥?{ayºÊ?Ú?ë,j­¢f£¢·h??àz¹®w¥¢¸¢·¦j:+v?¨?wèjØm¶?ÿ¾«?êçzZ+?ù???Ý¢j"?ú!¶iO?æ¬z·?vØ^¶m§ÿðÃnÆ?àþY&?