Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Xin Li <xin3.li@intel.com>
To:     linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org
Cc:     tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
        dave.hansen@linux.intel.com, hpa@zytor.com, peterz@infradead.org,
        andrew.cooper3@citrix.com, seanjc@google.com, pbonzini@redhat.com,
        ravi.v.shankar@intel.com, jiangshanlai@gmail.com,
        shan.kang@intel.com
Subject: [PATCH v6 10/33] x86/fred: add Kconfig option for FRED (CONFIG_X86_FRED)
Date:   Mon, 27 Mar 2023 00:58:15 -0700
Message-Id: <20230327075838.5403-11-xin3.li@intel.com>
In-Reply-To: <20230327075838.5403-1-xin3.li@intel.com>
References: <20230327075838.5403-1-xin3.li@intel.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: "H. Peter Anvin (Intel)" <hpa@zytor.com>

Add the configuration option CONFIG_X86_FRED to enable FRED.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Tested-by: Shan Kang <shan.kang@intel.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
---
 arch/x86/Kconfig | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index a825bf031f49..da62178bb246 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -500,6 +500,15 @@ config X86_CPU_RESCTRL
 
 	  Say N if unsure.
 
+config X86_FRED
+	bool "Flexible Return and Event Delivery"
+	depends on X86_64
+	help
+	  When enabled, try to use Flexible Return and Event Delivery
+	  instead of the legacy SYSCALL/SYSENTER/IDT architecture for
+	  ring transitions and exception/interrupt handling if the
+	  system supports.
+
 if X86_32
 config X86_BIGSMP
 	bool "Support for big SMP systems with more than 8 CPUs"
-- 
2.34.1