diff options
| -rw-r--r-- | arch/um/kernel/um_arch.c | 6 | ||||
| -rw-r--r-- | arch/x86/um/shared/sysdep/stub_32.h | 10 | ||||
| -rw-r--r-- | arch/x86/um/shared/sysdep/stub_64.h | 8 |
3 files changed, 14 insertions, 10 deletions
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index 99cdf4b2d648..427024f32b9f 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -325,10 +325,8 @@ int __init linux_main(int argc, char **argv) add_arg(DEFAULT_COMMAND_LINE_CONSOLE); host_task_size = os_get_top_address(); - /* reserve a few pages for the stubs (taking care of data alignment) */ - /* align the data portion */ - BUILD_BUG_ON(!is_power_of_2(STUB_DATA_PAGES)); - stub_start = (host_task_size - 1) & ~(STUB_DATA_PAGES * PAGE_SIZE - 1); + /* reserve a few pages for the stubs */ + stub_start = host_task_size - STUB_DATA_PAGES * PAGE_SIZE; /* another page for the code portion */ stub_start -= PAGE_SIZE; host_task_size = stub_start; diff --git a/arch/x86/um/shared/sysdep/stub_32.h b/arch/x86/um/shared/sysdep/stub_32.h index 0b44a86dd346..631a18d0ff44 100644 --- a/arch/x86/um/shared/sysdep/stub_32.h +++ b/arch/x86/um/shared/sysdep/stub_32.h @@ -112,10 +112,14 @@ static __always_inline void *get_stub_data(void) unsigned long ret; asm volatile ( - "movl %%esp,%0 ;" - "andl %1,%0" + "call _here_%=;" + "_here_%=:" + "popl %0;" + "andl %1, %0 ;" + "addl %2, %0 ;" : "=a" (ret) - : "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1))); + : "g" (~(UM_KERN_PAGE_SIZE - 1)), + "g" (UM_KERN_PAGE_SIZE)); return (void *)ret; } diff --git a/arch/x86/um/shared/sysdep/stub_64.h b/arch/x86/um/shared/sysdep/stub_64.h index 8e4ff39dcade..17153dfd780a 100644 --- a/arch/x86/um/shared/sysdep/stub_64.h +++ b/arch/x86/um/shared/sysdep/stub_64.h @@ -117,10 +117,12 @@ static __always_inline void *get_stub_data(void) unsigned long ret; asm volatile ( - "movq %%rsp,%0 ;" - "andq %1,%0" + "lea 0(%%rip), %0;" + "andq %1, %0 ;" + "addq %2, %0 ;" : "=a" (ret) - : "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1))); + : "g" (~(UM_KERN_PAGE_SIZE - 1)), + "g" (UM_KERN_PAGE_SIZE)); return (void *)ret; } |