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From:   Jinrong Liang <ljr.kernel@gmail.com>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Wanpeng Li <wanpengli@tencent.com>,
        Sean Christopherson <seanjc@google.com>,
        Jim Mattson <jmattson@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Joerg Roedel <joro@8bytes.org>,
        Jinrong Liang <cloudliang@tencent.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH] selftests: kvm/x86: Fix the warning in lib/x86_64/processor.c
Date:   Wed, 19 Jan 2022 22:03:25 +0800
Message-Id: <20220119140325.59369-1-cloudliang@tencent.com>
MIME-Version: 1.0
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From: Jinrong Liang <cloudliang@tencent.com>

The following warning appears when executing
make -C tools/testing/selftests/kvm

In file included from lib/x86_64/processor.c:11:
lib/x86_64/processor.c: In function ':
include/x86_64/processor.h:290:2: warning: 'ecx' may be used uninitialized in this
function [-Wmaybe-uninitialized]
  asm volatile("cpuid"
  ^~~
lib/x86_64/processor.c:1523:21: note: 'ecx' was declared here
  uint32_t eax, ebx, ecx, edx, max_ext_leaf;

Just initialize ecx to remove this warning.

Fixes: c8cc43c1eae2 ("selftests: KVM: avoid failures due to reserved
HyperTransport region")

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
---
 tools/testing/selftests/kvm/lib/x86_64/processor.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 59dcfe1967cc..4a4c7945cf3e 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -1520,7 +1520,7 @@ unsigned long vm_compute_max_gfn(struct kvm_vm *vm)
 {
 	const unsigned long num_ht_pages = 12 << (30 - vm->page_shift); /* 12 GiB */
 	unsigned long ht_gfn, max_gfn, max_pfn;
-	uint32_t eax, ebx, ecx, edx, max_ext_leaf;
+	uint32_t eax, ebx, ecx = 0, edx, max_ext_leaf;
 
 	max_gfn = (1ULL << (vm->pa_bits - vm->page_shift)) - 1;
 
-- 
2.27.0