Commit e644fa18 authored by Zhang Lei's avatar Zhang Lei Committed by Paolo Bonzini

KVM: arm64/sve: Fix vq_present() macro to yield a bool

The original implementation of vq_present() relied on aggressive
inlining in order for the compiler to know that the code is
correct, due to some const-casting issues.  This was causing sparse
and clang to complain, while GCC compiled cleanly.

Commit 0c529ff7 addressed this problem, but since vq_present()
is no longer a function, there is now no implicit casting of the
returned value to the return type (bool).

In set_sve_vls(), this uncast bit value is compared against a bool,
and so may spuriously compare as unequal when both are nonzero.  As
a result, KVM may reject valid SVE vector length configurations as
invalid, and vice versa.

Fix it by forcing the returned value to a bool.
Signed-off-by: default avatarZhang Lei <zhang.lei@jp.fujitsu.com>
Fixes: 0c529ff7 ("KVM: arm64: Implement vq_present() as a macro")
Signed-off-by: Dave Martin <Dave.Martin@arm.com> [commit message rewrite]
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent bb34e690
...@@ -208,7 +208,7 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) ...@@ -208,7 +208,7 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64) #define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
#define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64) #define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
#define vq_present(vqs, vq) ((vqs)[vq_word(vq)] & vq_mask(vq)) #define vq_present(vqs, vq) (!!((vqs)[vq_word(vq)] & vq_mask(vq)))
static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{ {
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment