Those pointers were initialized before call to _install_special_mapping after the commit f7b6eb3fa072 ("x86: Set context.vdso before installing the mapping"). This is not required anymore as special mappings have their vma name and don't use arch_vma_name() after commit a62c34bd2a8a ("x86, mm: Improve _install_special_mapping and fix x86 vdso naming"). So, this way to init looks less entangled. I even belive, we can remove null initializers: - on failure load_elf_binary() will not start a new thread; - arch_prctl will have the same pointers as before syscall. Cc: 0x7f454c46@xxxxxxxxx Cc: Cyrill Gorcunov <gorcunov@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: oleg@xxxxxxxxxx Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: linux-mm@xxxxxxxxx Cc: x86@xxxxxxxxxx Signed-off-by: Dmitry Safonov <dsafonov@xxxxxxxxxxxxx> --- arch/x86/entry/vdso/vma.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c index 23c881caabd1..e739002427ed 100644 --- a/arch/x86/entry/vdso/vma.c +++ b/arch/x86/entry/vdso/vma.c @@ -161,8 +161,6 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr) } text_start = addr - image->sym_vvar_start; - current->mm->context.vdso = (void __user *)text_start; - current->mm->context.vdso_image = image; /* * MAYWRITE to allow gdb to COW and set breakpoints @@ -189,14 +187,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr) if (IS_ERR(vma)) { ret = PTR_ERR(vma); do_munmap(mm, text_start, image->size); + } else { + current->mm->context.vdso = (void __user *)text_start; + current->mm->context.vdso_image = image; } up_fail: - if (ret) { - current->mm->context.vdso = NULL; - current->mm->context.vdso_image = NULL; - } - up_write(&mm->mmap_sem); return ret; } -- 2.10.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>