[PATCH] x86/vdso: Add ARCH_MAP_VDSO_X32 if CONFIG_X86_X32_ABI.

[PATCH] x86/vdso: Add ARCH_MAP_VDSO_X32 if CONFIG_X86_X32_ABI.

[Vinson Lee]

vdso_image_x32 is generated if CONFIG_X86_X32_ABI.

This patch fixes this build error on CentOS 6.8 with gcc 4.4.

  LD      init/built-in.o
arch/x86/built-in.o: In function `do_arch_prctl':
(.text+0x27466): undefined reference to `vdso_image_x32'
arch/x86/built-in.o: In function `do_arch_prctl':
(.text+0x27477): undefined reference to `vdso_image_x32'

Fixes: 2eefd8789698 ("x86/arch_prctl/vdso: Add ARCH_MAP_VDSO_*")
Signed-off-by: Vinson Lee <vlee@freedesktop.org>
---
 arch/x86/kernel/process_64.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index b34caea..b3760b3 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -592,7 +592,7 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 	}
 
 #ifdef CONFIG_CHECKPOINT_RESTORE
-# ifdef CONFIG_X86_X32
+# ifdef CONFIG_X86_X32_ABI
 	case ARCH_MAP_VDSO_X32:
 		return prctl_map_vdso(&vdso_image_x32, addr);
 # endif
-- 
1.7.1

Re: [PATCH] x86/vdso: Add ARCH_MAP_VDSO_X32 if CONFIG_X86_X32_ABI.

[Dmitry Safonov]

On 09/17/2016 03:51 AM, Vinson Lee wrote:
> vdso_image_x32 is generated if CONFIG_X86_X32_ABI.
>
> This patch fixes this build error on CentOS 6.8 with gcc 4.4.
>
>   LD      init/built-in.o
> arch/x86/built-in.o: In function `do_arch_prctl':
> (.text+0x27466): undefined reference to `vdso_image_x32'
> arch/x86/built-in.o: In function `do_arch_prctl':
> (.text+0x27477): undefined reference to `vdso_image_x32'
>
> Fixes: 2eefd8789698 ("x86/arch_prctl/vdso: Add ARCH_MAP_VDSO_*")
> Signed-off-by: Vinson Lee <vlee@freedesktop.org>

Thanks!
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>

Ifdeffery in arch/x86/include/asm/vdso.h dazzled my eyes.

-- 
              Dmitry

[tip:x86/vdso] x86/vdso: Use CONFIG_X86_X32_ABI to enable vdso prctl

[tip-bot for Vinson Lee]

Commit-ID:  6e68b08728ce3365c713f8663c6b05a79e2bbca1
Gitweb:     http://git.kernel.org/tip/6e68b08728ce3365c713f8663c6b05a79e2bbca1
Author:     Vinson Lee <vlee@freedesktop.org>
AuthorDate: Sat, 17 Sep 2016 00:51:53 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Tue, 20 Sep 2016 00:01:48 +0200

x86/vdso: Use CONFIG_X86_X32_ABI to enable vdso prctl

The prctl code which references vdso_image_x32 is built when CONFIG_X86_X32
is set. This results in the following build failure:

  LD      init/built-in.o
arch/x86/built-in.o: In function `do_arch_prctl':
(.text+0x27466): undefined reference to `vdso_image_x32'

vdso_image_x32 depends on CONFIG_X86_X32_ABI. So we need to make the prctl
depend on that as well.

[ tglx: Massaged changelog ]

Fixes: 2eefd8789698 ("x86/arch_prctl/vdso: Add ARCH_MAP_VDSO_*")
Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/r/1474073513-6656-1-git-send-email-vlee@freedesktop.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
 arch/x86/kernel/process_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index b26a009..b4603b7 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -592,7 +592,7 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 	}
 
 #ifdef CONFIG_CHECKPOINT_RESTORE
-# ifdef CONFIG_X86_X32
+# ifdef CONFIG_X86_X32_ABI
 	case ARCH_MAP_VDSO_X32:
 		return prctl_map_vdso(&vdso_image_x32, addr);
 # endif