diff options
Diffstat (limited to 'arch/x86/kernel/head64.c')
| -rw-r--r-- | arch/x86/kernel/head64.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 0c408f8c4ed4..2d29e47c056e 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -104,6 +104,12 @@ static bool __head check_la57_support(unsigned long physaddr) } #endif +/* Code in __startup_64() can be relocated during execution, but the compiler + * doesn't have to generate PC-relative relocations when accessing globals from + * that function. Clang actually does not generate them, which leads to + * boot-time crashes. To work around this problem, every global pointer must + * be adjusted using fixup_pointer(). + */ unsigned long __head __startup_64(unsigned long physaddr, struct boot_params *bp) { @@ -113,6 +119,7 @@ unsigned long __head __startup_64(unsigned long physaddr, p4dval_t *p4d; pudval_t *pud; pmdval_t *pmd, pmd_entry; + pteval_t *mask_ptr; bool la57; int i; unsigned int *next_pgt_ptr; @@ -196,7 +203,8 @@ unsigned long __head __startup_64(unsigned long physaddr, pmd_entry = __PAGE_KERNEL_LARGE_EXEC & ~_PAGE_GLOBAL; /* Filter out unsupported __PAGE_KERNEL_* bits: */ - pmd_entry &= __supported_pte_mask; + mask_ptr = fixup_pointer(&__supported_pte_mask, physaddr); + pmd_entry &= *mask_ptr; pmd_entry += sme_get_me_mask(); pmd_entry += physaddr; |