Re: [PATCH] KVM: mmu: Remove unused local variable

[Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>]

Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@siemens.com>
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
> 
> No one else checks for new build warnings?
> 
>  arch/x86/kvm/mmu.c |    1 -
>  1 files changed, 0 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index c16c4ca..9b9d773 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -2045,7 +2045,6 @@ static void kvm_send_hwpoison_signal(struct kvm *kvm, gfn_t gfn)
>  {
>  	char buf[1];
>  	void __user *hva;
> -	int r;
>  

Actually, the compiler still complain:

arch/x86/kvm/mmu.c: In function ‘kvm_send_hwpoison_signal’:
arch/x86/kvm/mmu.c:2051: warning: ignoring return value of ‘copy_from_user’, declared with attribute warn_unused_resul

Maybe we can fix it like this:


---
 arch/x86/kvm/mmu.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index c16c4ca..a62e3ba 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2049,7 +2049,7 @@ static void kvm_send_hwpoison_signal(struct kvm *kvm, gfn_t gfn)
 
 	/* Touch the page, so send SIGBUS */
 	hva = (void __user *)gfn_to_hva(kvm, gfn);
-	(void)copy_from_user(buf, hva, 1);
+	r = copy_from_user(buf, hva, 1);
 }
 
 static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
-- 
1.6.1.2