criu/vdso: Purge CONFIG_VDSO

Vigorously remove the config ifdef.
The config option *never* had any excuse to exist:
- for x86 we were grand
- for ppc64/arm64 patches to support mremap() on vdso were long ago
accepted, but regardless - it's not possible to disable CONFIG_VDSO for
those platforms in kernel
- for s390 - patches were mainstreamed not that long ago, but it's not
possible to disable the kernel config
- for arm32 it's possible to disable the kernel config, but kernel
returns to userspace historically through sigpage, not vdso.
That's the only platform that criu disallows to have CONFIG_VDSO=y in
kernel, but that's just meaningles. A kernel patch for sigpage mremap()
has gone into v4.13: commit 280e87e98c09 ("ARM: 8683/1: ARM32: Support
mremap() for sigpage/vDSO").

So, removing the config was long-lived item on my TODO list that bligted
arm32 users and made changes to vdso more complex by all "needed"
iffdeferry. Get rid of it with fire.

Fixes: #446

Signed-off-by: Dmitry Safonov <dima@arista.com>

1 files changed, 1 insertions, 5 deletions

diff --git a/Makefile b/Makefile
index 475d4abaf..09cf2406a 100644
--- a/Makefile
+++ b/Makefile
@@ -56,19 +56,16 @@ ifeq ($(ARCH),arm)
 endif
 
 ifeq ($(ARCH),aarch64)
-        VDSO		:= y
         DEFINES		:= -DCONFIG_AARCH64
 endif
 
 ifeq ($(ARCH),ppc64)
         LDARCH		:= powerpc:common64
-        VDSO		:= y
         DEFINES		:= -DCONFIG_PPC64 -D__SANE_USERSPACE_TYPES__
 endif
 
 ifeq ($(ARCH),x86)
         LDARCH		:= i386:x86-64
-        VDSO		:= y
         DEFINES		:= -DCONFIG_X86_64
 endif
 
@@ -81,7 +78,6 @@ endif
 ifeq ($(ARCH),s390)
         ARCH		:= s390
         SRCARCH		:= s390
-        VDSO		:= y
         DEFINES		:= -DCONFIG_S390
         CFLAGS_PIE	:= -fno-optimize-sibling-calls
 endif
@@ -90,7 +86,7 @@ CFLAGS_PIE		+= -DCR_NOGLIBC
 export CFLAGS_PIE
 
 LDARCH ?= $(SRCARCH)
-export LDARCH VDSO
+export LDARCH
 export PROTOUFIX DEFINES
 
 #