On Fri, Jun 19, 2020 at 8:30 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > Using uninitialized_var() is dangerous as it papers over real bugs[1] > (or can in the future), and suppresses unrelated compiler warnings (e.g. > "unused variable"). If the compiler thinks it is uninitialized, either > simply initialize the variable or make compiler changes. As a precursor > to removing[2] this[3] macro[4], just remove this variable since it was > actually unused: > > arch/powerpc/kvm/book3s_pr.c:1832:16: warning: unused variable 'vrsave' [-Wunused-variable] > unsigned long vrsave; > ^ > > [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@xxxxxxxxxx/ > [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@xxxxxxxxxxxxxx/ > [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@xxxxxxxxxxxxxx/ > [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@xxxxxxxxxxxxxx/ > > Suggested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > Fixes: f05ed4d56e9c ("KVM: PPC: Split out code from book3s.c into book3s_pr.c") > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > --- > arch/powerpc/kvm/book3s_pr.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c > index ef54f917bdaf..ed12dfbf9bb5 100644 > --- a/arch/powerpc/kvm/book3s_pr.c > +++ b/arch/powerpc/kvm/book3s_pr.c > @@ -1828,9 +1828,6 @@ static int kvmppc_vcpu_run_pr(struct kvm_vcpu *vcpu) > { > struct kvm_run *run = vcpu->run; > int ret; > -#ifdef CONFIG_ALTIVEC > - unsigned long uninitialized_var(vrsave); > -#endif > > /* Check if we can run the vcpu at all */ > if (!vcpu->arch.sane) { > -- -- Thanks, ~Nick Desaulniers
