Drivers: hv: Kconfig: Add HYPERV_VTL_MODE

Add HYPERV_VTL_MODE Kconfig flag for VTL mode.

Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1681192532-15460-5-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig
index 94982f0..0024210 100644 (file)
--- a/drivers/hv/Kconfig
+++ b/drivers/hv/Kconfig
@@ -13,6 +13,30 @@ config HYPERV
          Select this option to run Linux as a Hyper-V client operating
          system.
 
+config HYPERV_VTL_MODE
+       bool "Enable Linux to boot in VTL context"
+       depends on X86_64 && HYPERV
+       default n
+       help
+         Virtual Secure Mode (VSM) is a set of hypervisor capabilities and
+         enlightenments offered to host and guest partitions which enables
+         the creation and management of new security boundaries within
+         operating system software.
+
+         VSM achieves and maintains isolation through Virtual Trust Levels
+         (VTLs). Virtual Trust Levels are hierarchical, with higher levels
+         being more privileged than lower levels. VTL0 is the least privileged
+         level, and currently only other level supported is VTL2.
+
+         Select this option to build a Linux kernel to run at a VTL other than
+         the normal VTL0, which currently is only VTL2.  This option
+         initializes the x86 platform for VTL2, and adds the ability to boot
+         secondary CPUs directly into 64-bit context as required for VTLs other
+         than 0.  A kernel built with this option must run at VTL2, and will
+         not run as a normal guest.
+
+         If unsure, say N
+
 config HYPERV_TIMER
        def_bool HYPERV && X86