From: Paul Burton <paul.burton@xxxxxxxxxx>
VDSO code should not be using smp_processor_id(), since it is executed
in user mode.
Introduce a VDSO-specific path which will cause a compile-time
or link-time error (depending upon support for __compiletime_error) if
the VDSO ever incorrectly attempts to use smp_processor_id().
[Matt Redfearn <matt.redfearn@xxxxxxxxxx>: Move before change to
smp_processor_id in series]
Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
Signed-off-by: Matt Redfearn <matt.redfearn@xxxxxxxx>
---
arch/mips/include/asm/smp.h | 12 +++++++++++-
arch/mips/vdso/Makefile | 3 ++-
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/arch/mips/include/asm/smp.h b/arch/mips/include/asm/smp.h
index 88ebd83b3bf9..056a6bf13491 100644
--- a/arch/mips/include/asm/smp.h
+++ b/arch/mips/include/asm/smp.h
@@ -25,7 +25,17 @@ extern cpumask_t cpu_sibling_map[];
extern cpumask_t cpu_core_map[];
extern cpumask_t cpu_foreign_map[];
-#define raw_smp_processor_id() (current_thread_info()->cpu)
+static inline int raw_smp_processor_id(void)
+{
+#if defined(__VDSO__)
+ extern int vdso_smp_processor_id(void)
+ __compiletime_error("VDSO should not call smp_processor_id()");
+ return vdso_smp_processor_id();
+#else
+ return current_thread_info()->cpu;
+#endif
+}
+#define raw_smp_processor_id raw_smp_processor_id
/* Map from cpu id to sequential logical cpu number. This will only
not be idempotent when cpus failed to come on-line. */
diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile
index ce196046ac3e..477c463c89ec 100644
--- a/arch/mips/vdso/Makefile
+++ b/arch/mips/vdso/Makefile
@@ -7,7 +7,8 @@ ccflags-vdso := \
$(filter -I%,$(KBUILD_CFLAGS)) \
$(filter -E%,$(KBUILD_CFLAGS)) \
$(filter -mmicromips,$(KBUILD_CFLAGS)) \
- $(filter -march=%,$(KBUILD_CFLAGS))
+ $(filter -march=%,$(KBUILD_CFLAGS)) \
+ -D__VDSO__
cflags-vdso := $(ccflags-vdso) \
$(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \
-O2 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \
--
2.7.4
