[PATCH 4.9 05/44] MIPS: VDSO: avoid duplicate CAC_BASE definition

Greg Kroah-Hartman
2017-03-16T14:34:11Z

From: Arnd Bergmann <arnd@arndb.de>

commit 1742ac265046f34223e06d5d283496f0291be259 upstream.

vdso.h includes <spaces.h> implicitly after defining CONFIG_32BITS.
This defeats the override in mach-ip27/spaces.h, leading to
a build error that shows up in kernelci.org:

In file included from arch/mips/include/asm/mach-ip27/spaces.h:29:0,
from arch/mips/include/asm/page.h:12,
from arch/mips/vdso/vdso.h:26,
from arch/mips/vdso/gettimeofday.c:11:
arch/mips/include/asm/mach-generic/spaces.h:28:0: error: "CAC_BASE" redefined [-Werror]
#define CAC_BASE _AC(0x80000000, UL)

An earlier patch tried to make the second definition conditional,
but that patch had the #ifdef in the wrong place, and would lead
to another warning:

arch/mips/include/asm/io.h: In function 'phys_to_virt':
arch/mips/include/asm/io.h:138:9: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]

For all I can tell, there is no other reason than vdso32 to ever
include this file with CONFIG_32BITS set, and the vdso itself should
never refer to the base addresses as it is running in user space,
so adding an #ifdef here is safe.

Link: https://patchwork.kernel.org/patch/9418187/
Fixes: 3ffc17d8768b ("MIPS: Adjust MIPS64 CAC_BASE to reflect Config.K0")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15039/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/mips/include/asm/mach-ip27/spaces.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/mips/include/asm/mach-ip27/spaces.h
+++ b/arch/mips/include/asm/mach-ip27/spaces.h
@@ -12,14 +12,16 @@

/*
* IP27 uses the R10000's uncached attribute feature. Attribute 3 selects
- * uncached memory addressing.
+ * uncached memory addressing. Hide the definitions on 32-bit compilation
+ * of the compat-vdso code.
*/
-
+#ifdef CONFIG_64BIT
#define HSPEC_BASE 0x9000000000000000
#define IO_BASE 0x9200000000000000
#define MSPEC_BASE 0x9400000000000000
#define UNCAC_BASE 0x9600000000000000
#define CAC_BASE 0xa800000000000000
+#endif

#define TO_MSPEC(x) (MSPEC_BASE | ((x) & TO_PHYS_MASK))
#define TO_HSPEC(x) (HSPEC_BASE | ((x) & TO_PHYS_MASK))