diff options
Diffstat (limited to 'system/xen/xsa/xsa263-4.10-0007-x86-spec_ctrl-Split-X86_FEATURE_SC_MSR-into-PV-and-H.patch')
| -rw-r--r-- | system/xen/xsa/xsa263-4.10-0007-x86-spec_ctrl-Split-X86_FEATURE_SC_MSR-into-PV-and-H.patch | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/system/xen/xsa/xsa263-4.10-0007-x86-spec_ctrl-Split-X86_FEATURE_SC_MSR-into-PV-and-H.patch b/system/xen/xsa/xsa263-4.10-0007-x86-spec_ctrl-Split-X86_FEATURE_SC_MSR-into-PV-and-H.patch new file mode 100644 index 0000000000..a4e59aae9f --- /dev/null +++ b/system/xen/xsa/xsa263-4.10-0007-x86-spec_ctrl-Split-X86_FEATURE_SC_MSR-into-PV-and-H.patch @@ -0,0 +1,111 @@ +From 2acc4cba7eb2559bafdd4d8238466ad81322a35a Mon Sep 17 00:00:00 2001 +From: Andrew Cooper <andrew.cooper3@citrix.com> +Date: Tue, 17 Apr 2018 14:15:04 +0100 +Subject: [PATCH] x86/spec_ctrl: Split X86_FEATURE_SC_MSR into PV and HVM + variants + +In order to separately control whether MSR_SPEC_CTRL is virtualised for PV and +HVM guests, split the feature used to control runtime alternatives into two. +Xen will use MSR_SPEC_CTRL itself if either of these features are active. + +Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> +Reviewed-by: Wei Liu <wei.liu2@citrix.com> +Reviewed-by: Jan Beulich <jbeulich@suse.com> +Release-acked-by: Juergen Gross <jgross@suse.com> +(cherry picked from commit fa9eb09d446a1279f5e861e6b84fa8675dabf148) +--- + xen/arch/x86/spec_ctrl.c | 6 ++++-- + xen/include/asm-x86/cpufeatures.h | 5 +++-- + xen/include/asm-x86/spec_ctrl_asm.h | 12 ++++++------ + 3 files changed, 13 insertions(+), 10 deletions(-) + +diff --git a/xen/arch/x86/spec_ctrl.c b/xen/arch/x86/spec_ctrl.c +index 55ef79f..a940308 100644 +--- a/xen/arch/x86/spec_ctrl.c ++++ b/xen/arch/x86/spec_ctrl.c +@@ -112,7 +112,8 @@ static void __init print_details(enum ind_thunk thunk, uint64_t caps) + thunk == THUNK_RETPOLINE ? "RETPOLINE" : + thunk == THUNK_LFENCE ? "LFENCE" : + thunk == THUNK_JMP ? "JMP" : "?", +- boot_cpu_has(X86_FEATURE_SC_MSR) ? ++ (boot_cpu_has(X86_FEATURE_SC_MSR_PV) || ++ boot_cpu_has(X86_FEATURE_SC_MSR_HVM)) ? + default_xen_spec_ctrl & SPEC_CTRL_IBRS ? " IBRS+" : + " IBRS-" : "", + opt_ibpb ? " IBPB" : "", +@@ -286,7 +287,8 @@ void __init init_speculation_mitigations(void) + * need the IBRS entry/exit logic to virtualise IBRS support for + * guests. + */ +- setup_force_cpu_cap(X86_FEATURE_SC_MSR); ++ setup_force_cpu_cap(X86_FEATURE_SC_MSR_PV); ++ setup_force_cpu_cap(X86_FEATURE_SC_MSR_HVM); + + if ( ibrs ) + default_xen_spec_ctrl |= SPEC_CTRL_IBRS; +diff --git a/xen/include/asm-x86/cpufeatures.h b/xen/include/asm-x86/cpufeatures.h +index 32b7f04..b90aa2d 100644 +--- a/xen/include/asm-x86/cpufeatures.h ++++ b/xen/include/asm-x86/cpufeatures.h +@@ -26,8 +26,9 @@ XEN_CPUFEATURE(LFENCE_DISPATCH, (FSCAPINTS+0)*32+12) /* lfence set as Dispatch S + XEN_CPUFEATURE(IND_THUNK_LFENCE,(FSCAPINTS+0)*32+13) /* Use IND_THUNK_LFENCE */ + XEN_CPUFEATURE(IND_THUNK_JMP, (FSCAPINTS+0)*32+14) /* Use IND_THUNK_JMP */ + XEN_CPUFEATURE(XEN_IBPB, (FSCAPINTS+0)*32+15) /* IBRSB || IBPB */ +-XEN_CPUFEATURE(SC_MSR, (FSCAPINTS+0)*32+16) /* MSR_SPEC_CTRL used by Xen */ ++XEN_CPUFEATURE(SC_MSR_PV, (FSCAPINTS+0)*32+16) /* MSR_SPEC_CTRL used by Xen for PV */ ++XEN_CPUFEATURE(SC_MSR_HVM, (FSCAPINTS+0)*32+17) /* MSR_SPEC_CTRL used by Xen for HVM */ + XEN_CPUFEATURE(SC_RSB_PV, (FSCAPINTS+0)*32+18) /* RSB overwrite needed for PV */ + XEN_CPUFEATURE(SC_RSB_HVM, (FSCAPINTS+0)*32+19) /* RSB overwrite needed for HVM */ + XEN_CPUFEATURE(NO_XPTI, (FSCAPINTS+0)*32+20) /* XPTI mitigation not in use */ +-XEN_CPUFEATURE(SC_MSR_IDLE, (FSCAPINTS+0)*32+21) /* SC_MSR && default_xen_spec_ctrl */ ++XEN_CPUFEATURE(SC_MSR_IDLE, (FSCAPINTS+0)*32+21) /* (SC_MSR_PV || SC_MSR_HVM) && default_xen_spec_ctrl */ +diff --git a/xen/include/asm-x86/spec_ctrl_asm.h b/xen/include/asm-x86/spec_ctrl_asm.h +index 3d156ed..c659f3f 100644 +--- a/xen/include/asm-x86/spec_ctrl_asm.h ++++ b/xen/include/asm-x86/spec_ctrl_asm.h +@@ -224,36 +224,36 @@ + ALTERNATIVE __stringify(ASM_NOP40), \ + DO_OVERWRITE_RSB, X86_FEATURE_SC_RSB_HVM; \ + ALTERNATIVE __stringify(ASM_NOP36), \ +- DO_SPEC_CTRL_ENTRY_FROM_HVM, X86_FEATURE_SC_MSR ++ DO_SPEC_CTRL_ENTRY_FROM_HVM, X86_FEATURE_SC_MSR_HVM + + /* Use after an entry from PV context (syscall/sysenter/int80/int82/etc). */ + #define SPEC_CTRL_ENTRY_FROM_PV \ + ALTERNATIVE __stringify(ASM_NOP40), \ + DO_OVERWRITE_RSB, X86_FEATURE_SC_RSB_PV; \ + ALTERNATIVE __stringify(ASM_NOP25), \ +- __stringify(DO_SPEC_CTRL_ENTRY maybexen=0), X86_FEATURE_SC_MSR ++ __stringify(DO_SPEC_CTRL_ENTRY maybexen=0), X86_FEATURE_SC_MSR_PV + + /* Use in interrupt/exception context. May interrupt Xen or PV context. */ + #define SPEC_CTRL_ENTRY_FROM_INTR \ + ALTERNATIVE __stringify(ASM_NOP40), \ + DO_OVERWRITE_RSB, X86_FEATURE_SC_RSB_PV; \ + ALTERNATIVE __stringify(ASM_NOP33), \ +- __stringify(DO_SPEC_CTRL_ENTRY maybexen=1), X86_FEATURE_SC_MSR ++ __stringify(DO_SPEC_CTRL_ENTRY maybexen=1), X86_FEATURE_SC_MSR_PV + + /* Use when exiting to Xen context. */ + #define SPEC_CTRL_EXIT_TO_XEN \ + ALTERNATIVE __stringify(ASM_NOP17), \ +- DO_SPEC_CTRL_EXIT_TO_XEN, X86_FEATURE_SC_MSR ++ DO_SPEC_CTRL_EXIT_TO_XEN, X86_FEATURE_SC_MSR_PV + + /* Use when exiting to PV guest context. */ + #define SPEC_CTRL_EXIT_TO_PV \ + ALTERNATIVE __stringify(ASM_NOP24), \ +- DO_SPEC_CTRL_EXIT_TO_GUEST, X86_FEATURE_SC_MSR ++ DO_SPEC_CTRL_EXIT_TO_GUEST, X86_FEATURE_SC_MSR_PV + + /* Use when exiting to HVM guest context. */ + #define SPEC_CTRL_EXIT_TO_HVM \ + ALTERNATIVE __stringify(ASM_NOP24), \ +- DO_SPEC_CTRL_EXIT_TO_GUEST, X86_FEATURE_SC_MSR ++ DO_SPEC_CTRL_EXIT_TO_GUEST, X86_FEATURE_SC_MSR_HVM + + /* + * Use in IST interrupt/exception context. May interrupt Xen or PV context. +-- +2.1.4 + |