releases/6.6.26/kvm-x86-add-bhi_no.patch

   1 From 17233fed1ef4341bd93eff6906af3f7c8e93e818 Mon Sep 17 00:00:00 2001
   2 From: Daniel Sneddon <daniel.sneddon@linux.intel.com>
   3 Date: Wed, 13 Mar 2024 09:49:17 -0700
   4 Subject: KVM: x86: Add BHI_NO
   5
   6 From: Daniel Sneddon <daniel.sneddon@linux.intel.com>
   7
   8 commit ed2e8d49b54d677f3123668a21a57822d679651f upstream.
   9
  10 Intel processors that aren't vulnerable to BHI will set
  11 MSR_IA32_ARCH_CAPABILITIES[BHI_NO] = 1;. Guests may use this BHI_NO bit to
  12 determine if they need to implement BHI mitigations or not.  Allow this bit
  13 to be passed to the guests.
  14
  15 Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
  16 Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
  17 Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
  18 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  19 Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
  20 Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
  21 Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
  22 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  23 ---
  24  arch/x86/kvm/x86.c |    2 +-
  25  1 file changed, 1 insertion(+), 1 deletion(-)
  26
  27 --- a/arch/x86/kvm/x86.c
  28 +++ b/arch/x86/kvm/x86.c
  29 @@ -1621,7 +1621,7 @@ static bool kvm_is_immutable_feature_msr
  30          ARCH_CAP_PSCHANGE_MC_NO | ARCH_CAP_TSX_CTRL_MSR | ARCH_CAP_TAA_NO | \
  31          ARCH_CAP_SBDR_SSDP_NO | ARCH_CAP_FBSDP_NO | ARCH_CAP_PSDP_NO | \
  32          ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO | ARCH_CAP_GDS_NO | \
  33 -        ARCH_CAP_RFDS_NO | ARCH_CAP_RFDS_CLEAR)
  34 +        ARCH_CAP_RFDS_NO | ARCH_CAP_RFDS_CLEAR | ARCH_CAP_BHI_NO)
  35
  36  static u64 kvm_get_arch_capabilities(void)
  37  {