[tip:x86/alternatives] x86, alternatives: correct obsolete use of "u8" in static_cpu_has()

From: tip-bot for H. Peter Anvin
Date: Tue Jun 29 2010 - 03:07:44 EST


Commit-ID: a3d2d12f275fcd33d7edc34e6b4112b5a3c9d35d
Gitweb: http://git.kernel.org/tip/a3d2d12f275fcd33d7edc34e6b4112b5a3c9d35d
Author: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
AuthorDate: Mon, 28 Jun 2010 12:00:18 -0700
Committer: H. Peter Anvin <hpa@xxxxxxxxx>
CommitDate: Mon, 28 Jun 2010 22:04:47 -0700

x86, alternatives: correct obsolete use of "u8" in static_cpu_has()

gcc seems to pass unsigned words on as signed to the assembler, at
least with the %P format. As such, it is critical to get the correct
type.

Furthermore we are no longer limited to features < 256.

Reported-and-tested-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxx>
LKML-Reference: <4C2474EF.4050902@xxxxxxxxxxxxxx>
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/cpufeature.h | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 66878c5..e8b8896 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -291,7 +291,7 @@ extern const char * const x86_power_flags[32];
* patch the target code for additional performance.
*
*/
-static __always_inline __pure bool __static_cpu_has(u8 bit)
+static __always_inline __pure bool __static_cpu_has(u16 bit)
{
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
asm goto("1: jmp %l[t_no]\n"
@@ -339,7 +339,7 @@ static __always_inline __pure bool __static_cpu_has(u8 bit)
( \
__builtin_constant_p(boot_cpu_has(bit)) ? \
boot_cpu_has(bit) : \
- (__builtin_constant_p(bit) && !((bit) & ~0xff)) ? \
+ __builtin_constant_p(bit) ? \
__static_cpu_has(bit) : \
boot_cpu_has(bit) \
)
--
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