From 964b7aa0b040bdc6ec1c543ee620cda3f8b4c68a Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Sun, 14 Nov 2021 08:59:02 +0000 Subject: [PATCH] KVM: Fix steal time asm constraints In 64-bit mode, x86 instruction encoding allows us to use the low 8 bits of any GPR as an 8-bit operand. In 32-bit mode, however, we can only use the [abcd] registers. For which, GCC has the "q" constraint instead of the less restrictive "r". Also fix st->preempted, which is an input/output operand rather than an input. Fixes: 7e2175ebd695 ("KVM: x86: Fix recording of guest steal time / preempted status") Reported-by: kernel test robot Signed-off-by: David Woodhouse Message-Id: <89bf72db1b859990355f9c40713a34e0d2d86c98.camel@infradead.org> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2c03b76caf11..4ae77e1dadf6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3307,9 +3307,9 @@ static void record_steal_time(struct kvm_vcpu *vcpu) "xor %1, %1\n" "2:\n" _ASM_EXTABLE_UA(1b, 2b) - : "+r" (st_preempted), - "+&r" (err) - : "m" (st->preempted)); + : "+q" (st_preempted), + "+&r" (err), + "+m" (st->preempted)); if (err) goto out;