diff options
| -rw-r--r-- | arch/x86/kernel/head_32.S | 9 | ||||
| -rw-r--r-- | arch/x86/kernel/head_64.S | 15 |
2 files changed, 15 insertions, 9 deletions
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 9a6f8e820ae1..df541ac2071e 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -63,6 +63,8 @@ #define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD) #endif +#define SIZEOF_PTREGS 17*4 + /* * Number of possible pages in the lowmem region. * @@ -708,7 +710,12 @@ ENTRY(initial_page_table) .data .balign 4 ENTRY(initial_stack) - .long init_thread_union+THREAD_SIZE + /* + * The SIZEOF_PTREGS gap is a convention which helps the in-kernel + * unwinder reliably detect the end of the stack. + */ + .long init_thread_union + THREAD_SIZE - SIZEOF_PTREGS - \ + TOP_OF_KERNEL_STACK_PADDING; __INITRODATA int_msg: diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 1c5e5dba5704..b07cd27e33a5 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -66,13 +66,8 @@ startup_64: * tables and then reload them. */ - /* - * Setup stack for verify_cpu(). "-8" because initial_stack is defined - * this way, see below. Our best guess is a NULL ptr for stack - * termination heuristics and we don't want to break anything which - * might depend on it (kgdb, ...). - */ - leaq (__end_init_task - 8)(%rip), %rsp + /* Set up the stack for verify_cpu(), similar to initial_stack below */ + leaq (__end_init_task - SIZEOF_PTREGS)(%rip), %rsp /* Sanitize CPU configuration */ call verify_cpu @@ -329,7 +324,11 @@ ENDPROC(start_cpu0) GLOBAL(initial_gs) .quad INIT_PER_CPU_VAR(irq_stack_union) GLOBAL(initial_stack) - .quad init_thread_union+THREAD_SIZE-8 + /* + * The SIZEOF_PTREGS gap is a convention which helps the in-kernel + * unwinder reliably detect the end of the stack. + */ + .quad init_thread_union + THREAD_SIZE - SIZEOF_PTREGS __FINITDATA bad_address: |