[PATCH 3.16.y-ckt 048/129] KVM: ARM/arm64: avoid returning negative error code as bool

[Luis Henriques]

3.16.7-ckt12 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Will Deacon <will.deacon at arm.com>

commit 18d457661fb9fa69352822ab98d39331c3d0e571 upstream.

is_valid_cache returns true if the specified cache is valid.
Unfortunately, if the parameter passed it out of range, we return
-ENOENT, which ends up as true leading to potential hilarity.

This patch returns false on the failure path instead.

Cc: Christoffer Dall <christoffer.dall at linaro.org>
Cc: Marc Zyngier <marc.zyngier at arm.com>
Signed-off-by: Will Deacon <will.deacon at arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall at linaro.org>
Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 arch/arm/kvm/coproc.c     | 2 +-
 arch/arm64/kvm/sys_regs.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index c58a35116f63..7c732908f1df 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -742,7 +742,7 @@ static bool is_valid_cache(u32 val)
 	u32 level, ctype;
 
 	if (val >= CSSELR_MAX)
-		return -ENOENT;
+		return false;
 
 	/* Bottom bit is Instruction or Data bit.  Next 3 bits are level. */
         level = (val >> 1);
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 34f25a590bd7..444e8edd71b2 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -836,7 +836,7 @@ static bool is_valid_cache(u32 val)
 	u32 level, ctype;
 
 	if (val >= CSSELR_MAX)
-		return -ENOENT;
+		return false;
 
 	/* Bottom bit is Instruction or Data bit.  Next 3 bits are level. */
 	level = (val >> 1);