[PATCH 1/5] MIPS: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO

[James Hogan]

AT_VECTOR_SIZE_ARCH should be defined with the maximum number of
NEW_AUX_ENT entries that ARCH_DLINFO can contain, but it wasn't defined
for MIPS at all even though ARCH_DLINFO will contain one NEW_AUX_ENT for
the VDSO address.

This shouldn't be a problem as AT_VECTOR_SIZE_BASE includes space for
AT_BASE_PLATFORM which MIPS doesn't use, but lets define it now and add
the comment above ARCH_DLINFO as found in several other architectures to
remind future modifiers of ARCH_DLINFO to keep AT_VECTOR_SIZE_ARCH up to
date.

Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO")
Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
---
 arch/mips/include/asm/elf.h         | 1 +
 arch/mips/include/uapi/asm/auxvec.h | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/arch/mips/include/asm/elf.h b/arch/mips/include/asm/elf.h
index f5f45717968e..ede8c4ff56f7 100644
--- a/arch/mips/include/asm/elf.h
+++ b/arch/mips/include/asm/elf.h
@@ -458,6 +458,7 @@ extern const char *__elf_platform;
 #define ELF_ET_DYN_BASE		(TASK_SIZE / 3 * 2)
 #endif
 
+/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
 #define ARCH_DLINFO							\
 do {									\
 	NEW_AUX_ENT(AT_SYSINFO_EHDR,					\
diff --git a/arch/mips/include/uapi/asm/auxvec.h b/arch/mips/include/uapi/asm/auxvec.h
index c9c7195272c4..45ba259a3618 100644
--- a/arch/mips/include/uapi/asm/auxvec.h
+++ b/arch/mips/include/uapi/asm/auxvec.h
@@ -14,4 +14,6 @@
 /* Location of VDSO image. */
 #define AT_SYSINFO_EHDR		33
 
+#define AT_VECTOR_SIZE_ARCH 1 /* entries in ARCH_DLINFO */
+
 #endif /* __ASM_AUXVEC_H */
-- 
2.4.10