From 2db67aaca578ec4998b78dc85e2af214bc2e2770 Mon Sep 17 00:00:00 2001 From: Pavan Kumar Paluri Date: Mon, 14 Oct 2024 08:09:48 -0500 Subject: x86/virt: Provide "nosnp" boot option for sev kernel command line Provide a "nosnp" kernel command line option to prevent enabling of the RMP and SEV-SNP features in the host/hypervisor. Not initializing the RMP removes system overhead associated with RMP checks. [ bp: Actually make it a HV-only cmdline option. ] Co-developed-by: Eric Van Tassell Signed-off-by: Eric Van Tassell Signed-off-by: Pavan Kumar Paluri Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Tom Lendacky Link: https://lore.kernel.org/r/20241014130948.1476946-3-papaluri@amd.com --- Documentation/arch/x86/x86_64/boot-options.rst | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'Documentation') diff --git a/Documentation/arch/x86/x86_64/boot-options.rst b/Documentation/arch/x86/x86_64/boot-options.rst index 98d4805f0823..d69e3cfbdba5 100644 --- a/Documentation/arch/x86/x86_64/boot-options.rst +++ b/Documentation/arch/x86/x86_64/boot-options.rst @@ -305,3 +305,8 @@ The available options are: debug Enable debug messages. + + nosnp + Do not enable SEV-SNP (applies to host/hypervisor only). Setting + 'nosnp' avoids the RMP check overhead in memory accesses when + users do not want to run SEV-SNP guests. -- cgit v1.2.3