diff options
Diffstat (limited to 'arch/x86/hyperv/hv_init.c')
| -rw-r--r-- | arch/x86/hyperv/hv_init.c | 69 |
1 files changed, 44 insertions, 25 deletions
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index afdbda2dd7b7..e890fd37e9c2 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -17,7 +17,6 @@ #include <asm/desc.h> #include <asm/e820/api.h> #include <asm/sev.h> -#include <asm/ibt.h> #include <asm/hypervisor.h> #include <hyperv/hvhdk.h> #include <asm/mshyperv.h> @@ -37,7 +36,45 @@ #include <linux/export.h> void *hv_hypercall_pg; + +#ifdef CONFIG_X86_64 +static u64 __hv_hyperfail(u64 control, u64 param1, u64 param2) +{ + return U64_MAX; +} + +DEFINE_STATIC_CALL(__hv_hypercall, __hv_hyperfail); + +u64 hv_std_hypercall(u64 control, u64 param1, u64 param2) +{ + u64 hv_status; + + register u64 __r8 asm("r8") = param2; + asm volatile ("call " STATIC_CALL_TRAMP_STR(__hv_hypercall) + : "=a" (hv_status), ASM_CALL_CONSTRAINT, + "+c" (control), "+d" (param1), "+r" (__r8) + : : "cc", "memory", "r9", "r10", "r11"); + + return hv_status; +} + +typedef u64 (*hv_hypercall_f)(u64 control, u64 param1, u64 param2); + +static inline void hv_set_hypercall_pg(void *ptr) +{ + hv_hypercall_pg = ptr; + + if (!ptr) + ptr = &__hv_hyperfail; + static_call_update(__hv_hypercall, (hv_hypercall_f)ptr); +} +#else +static inline void hv_set_hypercall_pg(void *ptr) +{ + hv_hypercall_pg = ptr; +} EXPORT_SYMBOL_GPL(hv_hypercall_pg); +#endif union hv_ghcb * __percpu *hv_ghcb_pg; @@ -330,7 +367,7 @@ static int hv_suspend(void) * pointer is restored on resume. */ hv_hypercall_pg_saved = hv_hypercall_pg; - hv_hypercall_pg = NULL; + hv_set_hypercall_pg(NULL); /* Disable the hypercall page in the hypervisor */ rdmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); @@ -356,7 +393,7 @@ static void hv_resume(void) vmalloc_to_pfn(hv_hypercall_pg_saved); wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); - hv_hypercall_pg = hv_hypercall_pg_saved; + hv_set_hypercall_pg(hv_hypercall_pg_saved); hv_hypercall_pg_saved = NULL; /* @@ -476,8 +513,8 @@ void __init hyperv_init(void) if (hv_isolation_type_tdx() && !ms_hyperv.paravisor_present) goto skip_hypercall_pg_init; - hv_hypercall_pg = __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, - VMALLOC_END, GFP_KERNEL, PAGE_KERNEL_ROX, + hv_hypercall_pg = __vmalloc_node_range(PAGE_SIZE, 1, MODULES_VADDR, + MODULES_END, GFP_KERNEL, PAGE_KERNEL_ROX, VM_FLUSH_RESET_PERMS, NUMA_NO_NODE, __builtin_return_address(0)); if (hv_hypercall_pg == NULL) @@ -515,27 +552,9 @@ void __init hyperv_init(void) wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); } -skip_hypercall_pg_init: - /* - * Some versions of Hyper-V that provide IBT in guest VMs have a bug - * in that there's no ENDBR64 instruction at the entry to the - * hypercall page. Because hypercalls are invoked via an indirect call - * to the hypercall page, all hypercall attempts fail when IBT is - * enabled, and Linux panics. For such buggy versions, disable IBT. - * - * Fixed versions of Hyper-V always provide ENDBR64 on the hypercall - * page, so if future Linux kernel versions enable IBT for 32-bit - * builds, additional hypercall page hackery will be required here - * to provide an ENDBR32. - */ -#ifdef CONFIG_X86_KERNEL_IBT - if (cpu_feature_enabled(X86_FEATURE_IBT) && - *(u32 *)hv_hypercall_pg != gen_endbr()) { - setup_clear_cpu_cap(X86_FEATURE_IBT); - pr_warn("Disabling IBT because of Hyper-V bug\n"); - } -#endif + hv_set_hypercall_pg(hv_hypercall_pg); +skip_hypercall_pg_init: /* * hyperv_init() is called before LAPIC is initialized: see * apic_intr_mode_init() -> x86_platform.apic_post_init() and |