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From: Bill Wendling <morbo@google.com>
To: kvm@vger.kernel.org
Subject: [kvm-unit-tests PATCH] x86: remove memory constraint from "mov" instruction
Date: Mon, 9 Sep 2019 14:19:20 -0700	[thread overview]
Message-ID: <CAGG=3QWteHe8zCdXQVQv+42pMO2k4XvAbj_A=ptRUi9E2AwT2w@mail.gmail.com> (raw)

The "mov" instruction to get the error code shouldn't move into a memory
location. Don't allow the compiler to make this decision. Instead
specify that only a register is appropriate here.

Signed-off-by: Bill Wendling <morbo@google.com>
---
 lib/x86/desc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/x86/desc.c b/lib/x86/desc.c
index 5f37cef..451f504 100644
--- a/lib/x86/desc.c
+++ b/lib/x86/desc.c
@@ -263,7 +263,7 @@ unsigned exception_error_code(void)
 {
     unsigned short error_code;

-    asm("mov %%gs:6, %0" : "=rm"(error_code));
+    asm("mov %%gs:6, %0" : "=r"(error_code));
     return error_code;
 }

             reply	other threads:[~2019-09-09 21:21 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-09 21:19 Bill Wendling [this message]
2019-09-10 16:44 ` [kvm-unit-tests PATCH] x86: remove memory constraint from "mov" instruction Jim Mattson
2019-09-11 19:08 ` Sean Christopherson
2019-09-11 22:35   ` Bill Wendling
2019-09-12 20:59     ` [PATCH] " Bill Wendling
2019-09-19 21:44       ` Sean Christopherson
2019-09-24 14:02 ` [kvm-unit-tests PATCH] " Paolo Bonzini

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