diff options
| -rw-r--r-- | arch/x86/kernel/machine_kexec_64.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index dfb91091f451..15088d14904f 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -347,6 +347,22 @@ int machine_kexec_prepare(struct kimage *image) unsigned long reloc_end = (unsigned long)__relocate_kernel_end; int result; + /* + * Some early TDX-capable platforms have an erratum. A kernel + * partial write (a write transaction of less than cacheline + * lands at memory controller) to TDX private memory poisons that + * memory, and a subsequent read triggers a machine check. + * + * On those platforms the old kernel must reset TDX private + * memory before jumping to the new kernel otherwise the new + * kernel may see unexpected machine check. For simplicity + * just fail kexec/kdump on those platforms. + */ + if (boot_cpu_has_bug(X86_BUG_TDX_PW_MCE)) { + pr_info_once("Not allowed on platform with tdx_pw_mce bug\n"); + return -EOPNOTSUPP; + } + /* Setup the identity mapped 64bit page table */ result = init_pgtable(image, __pa(control_page)); if (result) |