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Date:   Mon, 20 Jul 2020 13:49:19 -0700
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Subject: [PATCH v3 05/11] x86/percpu: Remove "e" constraint from XADD
From:   Nick Desaulniers <ndesaulniers@google.com>
To:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>
Cc:     Dennis Zhou <dennis@kernel.org>, Tejun Heo <tj@kernel.org>,
        Christoph Lameter <cl@linux.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com,
        Brian Gerst <brgerst@gmail.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
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From: Brian Gerst <brgerst@gmail.com>

The "e" constraint represents a constant, but the XADD instruction doesn't
accept immediate operands.

Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
 arch/x86/include/asm/percpu.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
index 2a24f3c795eb..9bb5440d98d3 100644
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -220,7 +220,7 @@ do {									\
 		break;							\
 	case 8:								\
 		asm qual ("xaddq %0, "__percpu_arg(1)			\
-			    : "+re" (paro_ret__), "+m" (var)		\
+			    : "+r" (paro_ret__), "+m" (var)		\
 			    : : "memory");				\
 		break;							\
 	default: __bad_percpu_size();					\
-- 
2.28.0.rc0.105.gf9edc3c819-goog