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Date:   Fri,  8 Apr 2022 21:05:42 +0000
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Subject: [RFC V1 PATCH 2/5] selftests: kvm: Fix inline assembly for hypercall
From:   Vishal Annapurve <vannapurve@google.com>
To:     x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org
Cc:     pbonzini@redhat.com, vkuznets@redhat.com, wanpengli@tencent.com,
        jmattson@google.com, joro@8bytes.org, tglx@linutronix.de,
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        vbabka@suse.cz, marcorr@google.com, erdemaktas@google.com,
        pgonda@google.com, seanjc@google.com, diviness@google.com,
        Vishal Annapurve <vannapurve@google.com>
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Precedence: bulk

Fix inline assembly for hypercall to explicitly set
eax with hypercall number to allow the implementation
to work even in cases where compiler would inline the
function.

Signed-off-by: Vishal Annapurve <vannapurve@google.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 9f000dfb5594..4d88e1a553bf 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -1461,7 +1461,7 @@ uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2,
 
 	asm volatile("vmcall"
 		     : "=a"(r)
-		     : "b"(a0), "c"(a1), "d"(a2), "S"(a3));
+		     : "a"(nr), "b"(a0), "c"(a1), "d"(a2), "S"(a3));
 	return r;
 }
 
-- 
2.35.1.1178.g4f1659d476-goog