From ca3739327b89bb4053a62ac41b67b106c1967ab0 Mon Sep 17 00:00:00 2001 From: Anthony Liguori <aliguori@us.ibm.com> Date: Thu, 3 Jul 2008 19:02:36 +0300 Subject: [PATCH] x86: KVM guest: Add memory clobber to hypercalls Hypercalls can modify arbitrary regions of memory. Make sure to indicate this in the clobber list. This fixes a hang when using KVM_GUEST kernel built with GCC 4.3.0. This was originally spotted and analyzed by Marcelo. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com> --- include/asm-x86/kvm_para.h | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/include/asm-x86/kvm_para.h b/include/asm-x86/kvm_para.h index bfd9900742bf..76f392146daa 100644 --- a/include/asm-x86/kvm_para.h +++ b/include/asm-x86/kvm_para.h @@ -71,7 +71,8 @@ static inline long kvm_hypercall0(unsigned int nr) long ret; asm volatile(KVM_HYPERCALL : "=a"(ret) - : "a"(nr)); + : "a"(nr) + : "memory"); return ret; } @@ -80,7 +81,8 @@ static inline long kvm_hypercall1(unsigned int nr, unsigned long p1) long ret; asm volatile(KVM_HYPERCALL : "=a"(ret) - : "a"(nr), "b"(p1)); + : "a"(nr), "b"(p1) + : "memory"); return ret; } @@ -90,7 +92,8 @@ static inline long kvm_hypercall2(unsigned int nr, unsigned long p1, long ret; asm volatile(KVM_HYPERCALL : "=a"(ret) - : "a"(nr), "b"(p1), "c"(p2)); + : "a"(nr), "b"(p1), "c"(p2) + : "memory"); return ret; } @@ -100,7 +103,8 @@ static inline long kvm_hypercall3(unsigned int nr, unsigned long p1, long ret; asm volatile(KVM_HYPERCALL : "=a"(ret) - : "a"(nr), "b"(p1), "c"(p2), "d"(p3)); + : "a"(nr), "b"(p1), "c"(p2), "d"(p3) + : "memory"); return ret; } @@ -111,7 +115,8 @@ static inline long kvm_hypercall4(unsigned int nr, unsigned long p1, long ret; asm volatile(KVM_HYPERCALL : "=a"(ret) - : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)); + : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4) + : "memory"); return ret; } -- 2.34.1