The xfeature mask is 64bit so a shift from a number to its mask should
have LL prefix or else nr > 31 will be lost. This is not a problem now
but should XFEATURE_MASK_SUPERVISOR gain a bit >31 then this check won't
catch it.
Use BIT_ULL() to compute a mask from a number.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
arch/x86/kernel/fpu/xstate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 87a57b7642d36..69d5740ed2546 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -444,7 +444,7 @@ static int xfeature_uncompacted_offset(int xfeature_nr)
* format. Checking a supervisor state's uncompacted offset is
* an error.
*/
- if (XFEATURE_MASK_SUPERVISOR & (1 << xfeature_nr)) {
+ if (XFEATURE_MASK_SUPERVISOR & BIT_ULL(xfeature_nr)) {
WARN_ONCE(1, "No fixed offset for xstate %d\n", xfeature_nr);
return -1;
}
--
2.20.0.rc1
