From: Sven Schnelle svens@linux.ibm.com
commit d57778feb9878aa6b79c615fd029c2112d40a747 upstream.
With the upcoming move of the svc sigreturn instruction from the signal frame to vdso we need to have vdso always enabled.
Signed-off-by: Sven Schnelle svens@linux.ibm.com Reviewed-by: Heiko Carstens hca@linux.ibm.com Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/s390/include/asm/elf.h | 11 ++++------- arch/s390/kernel/vdso.c | 21 ++++----------------- 2 files changed, 8 insertions(+), 24 deletions(-)
--- a/arch/s390/include/asm/elf.h +++ b/arch/s390/include/asm/elf.h @@ -146,8 +146,6 @@ typedef s390_compat_regs compat_elf_greg
#include <asm/vdso.h>
-extern unsigned int vdso_enabled; - /* * This is used to ensure we don't load something for the wrong architecture. */ @@ -268,11 +266,10 @@ do { \ #define STACK_RND_MASK MMAP_RND_MASK
/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */ -#define ARCH_DLINFO \ -do { \ - if (vdso_enabled) \ - NEW_AUX_ENT(AT_SYSINFO_EHDR, \ - (unsigned long)current->mm->context.vdso_base); \ +#define ARCH_DLINFO \ +do { \ + NEW_AUX_ENT(AT_SYSINFO_EHDR, \ + (unsigned long)current->mm->context.vdso_base); \ } while (0)
struct linux_binprm; --- a/arch/s390/kernel/vdso.c +++ b/arch/s390/kernel/vdso.c @@ -37,18 +37,6 @@ enum vvar_pages { VVAR_NR_PAGES, };
-unsigned int __read_mostly vdso_enabled = 1; - -static int __init vdso_setup(char *str) -{ - bool enabled; - - if (!kstrtobool(str, &enabled)) - vdso_enabled = enabled; - return 1; -} -__setup("vdso=", vdso_setup); - #ifdef CONFIG_TIME_NS struct vdso_data *arch_get_vdso_data(void *vvar_page) { @@ -176,7 +164,7 @@ int arch_setup_additional_pages(struct l int rc;
BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES); - if (!vdso_enabled || is_compat_task()) + if (is_compat_task()) return 0; if (mmap_write_lock_killable(mm)) return -EINTR; @@ -218,10 +206,9 @@ static int __init vdso_init(void)
vdso_pages = (vdso64_end - vdso64_start) >> PAGE_SHIFT; pages = kcalloc(vdso_pages + 1, sizeof(struct page *), GFP_KERNEL); - if (!pages) { - vdso_enabled = 0; - return -ENOMEM; - } + if (!pages) + panic("failed to allocate VDSO pages"); + for (i = 0; i < vdso_pages; i++) pages[i] = virt_to_page(vdso64_start + i * PAGE_SIZE); pages[vdso_pages] = NULL;