From 08094d48c130d3ae6182296ef3c9561ca1066b39 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Sun, 12 Jul 2015 14:38:58 -0700 Subject: Align stack to 16 bytes when calling __setcontext Don't use pop to restore %rdi so that stack is aligned to 16 bytes when calling __setcontext. [BZ #18661] * sysdeps/unix/sysv/linux/x86_64/__start_context.S (__start_context): Don't use pop to restore %rdi so that stack is aligned to 16 bytes when calling __setcontext. --- sysdeps/unix/sysv/linux/x86_64/__start_context.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sysdeps/unix/sysv/linux/x86_64/__start_context.S b/sysdeps/unix/sysv/linux/x86_64/__start_context.S index 52a5afa9a6..96366e0536 100644 --- a/sysdeps/unix/sysv/linux/x86_64/__start_context.S +++ b/sysdeps/unix/sysv/linux/x86_64/__start_context.S @@ -31,8 +31,8 @@ ENTRY(__start_context) on the stack pointer for the next context. */ movq %rbx, %rsp - popq %rdi /* This is the next context. */ - cfi_adjust_cfa_offset(-8) + /* Don't use pop here so that stack is aligned to 16 bytes. */ + movq (%rsp), %rdi /* This is the next context. */ testq %rdi, %rdi je 2f /* If it is zero exit. */ -- cgit 1.4.1