Merge Linus master into drm-next

The merge is clean, but the arm build fails afterwards,
due to API changes in the regulator tree.

I've included the patch into the merge to fix the build.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 18 insertions, 3 deletions

diff --git a/arch/x86/include/uapi/asm/sigcontext.h b/arch/x86/include/uapi/asm/sigcontext.h
index d8b9f9081e86..16dc4e8a2cd3 100644
--- a/arch/x86/include/uapi/asm/sigcontext.h
+++ b/arch/x86/include/uapi/asm/sigcontext.h
@@ -177,9 +177,24 @@ struct sigcontext {
 	__u64 rip;
 	__u64 eflags;		/* RFLAGS */
 	__u16 cs;
-	__u16 gs;
-	__u16 fs;
-	__u16 __pad0;
+
+	/*
+	 * Prior to 2.5.64 ("[PATCH] x86-64 updates for 2.5.64-bk3"),
+	 * Linux saved and restored fs and gs in these slots.  This
+	 * was counterproductive, as fsbase and gsbase were never
+	 * saved, so arch_prctl was presumably unreliable.
+	 *
+	 * If these slots are ever needed for any other purpose, there
+	 * is some risk that very old 64-bit binaries could get
+	 * confused.  I doubt that many such binaries still work,
+	 * though, since the same patch in 2.5.64 also removed the
+	 * 64-bit set_thread_area syscall, so it appears that there is
+	 * no TLS API that works in both pre- and post-2.5.64 kernels.
+	 */
+	__u16 __pad2;		/* Was gs. */
+	__u16 __pad1;		/* Was fs. */
+
+	__u16 ss;
 	__u64 err;
 	__u64 trapno;
 	__u64 oldmask;