From: Yu-cheng Yu <yu-cheng.yu@intel.com>

Remote Action Request (RAR) is a TLB flushing broadcast facility.
This patch introduces RAR MSRs.  RAR is introduced in later patches.

There are five RAR MSRs:

  MSR_CORE_CAPABILITIES
  MSR_IA32_RAR_CTRL
  MSR_IA32_RAR_ACT_VEC
  MSR_IA32_RAR_PAYLOAD_BASE
  MSR_IA32_RAR_INFO

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rik van Riel <riel@surriel.com>
---
 arch/x86/include/asm/msr-index.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index c848dd4bfceb..adff8f0dc7bb 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -122,6 +122,17 @@
 #define SNB_C3_AUTO_UNDEMOTE		(1UL << 27)
 #define SNB_C1_AUTO_UNDEMOTE		(1UL << 28)
 
+/*
+ * Remote Action Requests (RAR) MSRs
+ */
+#define MSR_IA32_RAR_CTRL		0x000000ed
+#define MSR_IA32_RAR_ACT_VEC		0x000000ee
+#define MSR_IA32_RAR_PAYLOAD_BASE	0x000000ef
+#define MSR_IA32_RAR_INFO		0x000000f0
+
+#define RAR_CTRL_ENABLE			BIT(31)
+#define RAR_CTRL_IGNORE_IF		BIT(30)
+
 #define MSR_MTRRcap			0x000000fe
 
 #define MSR_IA32_ARCH_CAPABILITIES	0x0000010a
-- 
2.49.0

On Mon, May 19, 2025 at 09:02:27PM -0400, Rik van Riel wrote:
> From: Yu-cheng Yu <yu-cheng.yu@intel.com>
> 
> Remote Action Request (RAR) is a TLB flushing broadcast facility.
> This patch introduces RAR MSRs.  RAR is introduced in later patches.
> 
> There are five RAR MSRs:
> 
>   MSR_CORE_CAPABILITIES
>   MSR_IA32_RAR_CTRL
>   MSR_IA32_RAR_ACT_VEC
>   MSR_IA32_RAR_PAYLOAD_BASE
>   MSR_IA32_RAR_INFO
> 
> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
> Signed-off-by: Rik van Riel <riel@surriel.com>
> ---
>  arch/x86/include/asm/msr-index.h | 11 +++++++++++
>  1 file changed, 11 insertions(+)

You can merge this one with the previous one.

-- 
Regards/Gruss,
    Boris.

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