[PATCH] x86: Don't use NOPL on 32-bit cpu's because not all systems support it.

David Sanders
2008-09-16T15:59:35Z

From: David Sanders <linux@sandersweb.net>

Currently in alternative.c NOPLs are introduced based on the synthetic
cpu feature X86_FEATURE_NOPL. However, some systems (like Virtual PC 2007)
appear to support it but then will not boot 50% of the time because of
the NOPLs (when paravirtualization support is built into kernel).
This patch standardizes the treatment of NOPL to be like
include/asm-x86/nops.h which only uses NOPLs on 64-bit processors.

Applies to 2.6.27-rc6.

Signed-off-by: David Sanders <linux@sandersweb.net>
---
arch/x86/kernel/alternative.c | 8 ++++++--
1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 65a0c1b..dceb843 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -160,8 +160,12 @@ const unsigned char *const *find_nop_table(void)
return k8_nops;
else if (boot_cpu_has(X86_FEATURE_K7))
return k7_nops;
- else if (boot_cpu_has(X86_FEATURE_NOPL))
- return p6_nops;
+ /*
+ * Don't use NOPL in 32-bit mode because some Emulators
+ * do not support it.
+ */
+ /* else if (boot_cpu_has(X86_FEATURE_NOPL))
+ return p6_nops; */
else
return intel_nops;
}
--
1.6.0.2.229.g1293c