diff options
Diffstat (limited to 'arch/x86/um/shared/sysdep/stub_32.h')
| -rw-r--r-- | arch/x86/um/shared/sysdep/stub_32.h | 33 |
1 files changed, 22 insertions, 11 deletions
diff --git a/arch/x86/um/shared/sysdep/stub_32.h b/arch/x86/um/shared/sysdep/stub_32.h index 8ea69211e53c..c3891c1ada26 100644 --- a/arch/x86/um/shared/sysdep/stub_32.h +++ b/arch/x86/um/shared/sysdep/stub_32.h @@ -7,8 +7,8 @@ #define __SYSDEP_STUB_H #include <asm/ptrace.h> +#include <generated/asm-offsets.h> -#define STUB_SYSCALL_RET EAX #define STUB_MMAP_NR __NR_mmap2 #define MMAP_OFFSET(o) ((o) >> UM_KERN_PAGE_SHIFT) @@ -77,17 +77,28 @@ static inline void trap_myself(void) __asm("int3"); } -static inline void remap_stack(int fd, unsigned long offset) +static void inline remap_stack_and_trap(void) { - __asm__ volatile ("movl %%eax,%%ebp ; movl %0,%%eax ; int $0x80 ;" - "movl %7, %%ebx ; movl %%eax, (%%ebx)" - : : "g" (STUB_MMAP_NR), "b" (STUB_DATA), - "c" (UM_KERN_PAGE_SIZE), - "d" (PROT_READ | PROT_WRITE), - "S" (MAP_FIXED | MAP_SHARED), "D" (fd), - "a" (offset), - "i" (&((struct stub_data *) STUB_DATA)->child_err) - : "memory"); + __asm__ volatile ( + "movl %%esp,%%ebx ;" + "andl %0,%%ebx ;" + "movl %1,%%eax ;" + "movl %%ebx,%%edi ; addl %2,%%edi ; movl (%%edi),%%edi ;" + "movl %%ebx,%%ebp ; addl %3,%%ebp ; movl (%%ebp),%%ebp ;" + "int $0x80 ;" + "addl %4,%%ebx ; movl %%eax, (%%ebx) ;" + "int $3" + : : + "g" (~(UM_KERN_PAGE_SIZE - 1)), + "g" (STUB_MMAP_NR), + "g" (UML_STUB_FIELD_FD), + "g" (UML_STUB_FIELD_OFFSET), + "g" (UML_STUB_FIELD_CHILD_ERR), + "c" (UM_KERN_PAGE_SIZE), + "d" (PROT_READ | PROT_WRITE), + "S" (MAP_FIXED | MAP_SHARED) + : + "memory"); } #endif |