While altcall is already used for them, the functions want announcing in .init.rodata.cf_clobber, even if the resulting static variables aren't otherwise used.
While doing this also move ctxt_switch_masking to .data.ro_after_init. Signed-off-by: Jan Beulich <[email protected]> --- a/xen/arch/x86/cpu/amd.c +++ b/xen/arch/x86/cpu/amd.c @@ -258,6 +258,11 @@ static void cf_check amd_ctxt_switch_mas #undef LAZY } +#ifdef CONFIG_XEN_IBT /* Announce the function to ENDBR clobbering logic. */ +static const typeof(ctxt_switch_masking) __initconst_cf_clobber __used csm = + amd_ctxt_switch_masking; +#endif + /* * Mask the features and extended features returned by CPUID. Parameters are * set from the boot line via two methods: --- a/xen/arch/x86/cpu/common.c +++ b/xen/arch/x86/cpu/common.c @@ -119,7 +119,7 @@ static const struct cpu_dev __initconst_ static const struct cpu_dev *this_cpu = &default_cpu; static DEFINE_PER_CPU(uint64_t, msr_misc_features); -void (* __read_mostly ctxt_switch_masking)(const struct vcpu *next); +void (* __ro_after_init ctxt_switch_masking)(const struct vcpu *next); bool __init probe_cpuid_faulting(void) { --- a/xen/arch/x86/cpu/intel.c +++ b/xen/arch/x86/cpu/intel.c @@ -220,6 +220,11 @@ static void cf_check intel_ctxt_switch_m #undef LAZY } +#ifdef CONFIG_XEN_IBT /* Announce the function to ENDBR clobbering logic. */ +static const typeof(ctxt_switch_masking) __initconst_cf_clobber __used csm = + intel_ctxt_switch_masking; +#endif + /* * opt_cpuid_mask_ecx/edx: cpuid.1[ecx, edx] feature mask. * For example, E8400[Intel Core 2 Duo Processor series] ecx = 0x0008E3FD,
