File xsa456-0g.patch of Package xen.35285

# Commit 4b3da946ad7e3452761478ae683da842e7ff20d6
# Date 2024-04-09 15:26:27 +0100
# Author Andrew Cooper <andrew.cooper3@citrix.com>
# Committer Andrew Cooper <andrew.cooper3@citrix.com>
x86/cpuid: Don't expose {IPRED,RRSBA,BHI}_CTRL to PV guests

All of these are prediction-mode (i.e. CPL) based.  They don't operate as
advertised in PV context.

Fixes: 4dd676070684 ("x86/spec-ctrl: Expose IPRED_CTRL to guests")
Fixes: 478e4787fa64 ("x86/spec-ctrl: Expose RRSBA_CTRL to guests")
Fixes: 583f1d095052 ("x86/spec-ctrl: Expose BHI_CTRL to guests")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>

--- a/xen/include/public/arch-x86/cpufeatureset.h
+++ b/xen/include/public/arch-x86/cpufeatureset.h
@@ -289,10 +289,10 @@ XEN_CPUFEATURE(SRSO_NO,            11*32
 
 /* Intel-defined CPU features, CPUID level 0x00000007:2.edx, word 13 */
 XEN_CPUFEATURE(INTEL_PSFD,         13*32+ 0) /*A  MSR_SPEC_CTRL.PSFD */
-XEN_CPUFEATURE(IPRED_CTRL,         13*32+ 1) /*A  MSR_SPEC_CTRL.IPRED_DIS_* */
-XEN_CPUFEATURE(RRSBA_CTRL,         13*32+ 2) /*A  MSR_SPEC_CTRL.RRSBA_DIS_* */
+XEN_CPUFEATURE(IPRED_CTRL,         13*32+ 1) /*S  MSR_SPEC_CTRL.IPRED_DIS_* */
+XEN_CPUFEATURE(RRSBA_CTRL,         13*32+ 2) /*S  MSR_SPEC_CTRL.RRSBA_DIS_* */
 XEN_CPUFEATURE(DDP_CTRL,           13*32+ 3) /*   MSR_SPEC_CTRL.DDP_DIS_U */
-XEN_CPUFEATURE(BHI_CTRL,           13*32+ 4) /*A  MSR_SPEC_CTRL.BHI_DIS_S */
+XEN_CPUFEATURE(BHI_CTRL,           13*32+ 4) /*S  MSR_SPEC_CTRL.BHI_DIS_S */
 XEN_CPUFEATURE(MCDT_NO,            13*32+ 5) /*A  MCDT_NO */
 
 /* Intel-defined CPU features, CPUID level 0x00000007:1.ecx, word 14 */