ARM: 8226/1: cacheflush: get rid of restarting block

We cannot restart cacheflush safely if a process provides user-defined
signal handler and signal is pending. In this case -EINTR is returned
and it is expected that process re-invokes syscall. However, there are
a few problems with that:
 * looks like nobody bothers checking return value from cacheflush
 * but if it did, we don't provide the restart address for that, so the
   process has to use the same range again
 * ...and again, what might lead to looping forever

So, remove cacheflush restarting code and terminate cache flushing
as early as fatal signal is pending.

Cc: stable@vger.kernel.org # 3.12+
Reported-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 0 insertions, 11 deletions

diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index fc44d3761f9e..ce73ab635414 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -44,16 +44,6 @@ struct cpu_context_save {
 	__u32	extra[2];		/* Xscale 'acc' register, etc */
 };
 
-struct arm_restart_block {
-	union {
-		/* For user cache flushing */
-		struct {
-			unsigned long start;
-			unsigned long end;
-		} cache;
-	};
-};
-
 /*
  * low level task data that entry.S needs immediate access to.
  * __switch_to() assumes cpu_context follows immediately after cpu_domain.
@@ -79,7 +69,6 @@ struct thread_info {
 	unsigned long		thumbee_state;	/* ThumbEE Handler Base register */
 #endif
 	struct restart_block	restart_block;
-	struct arm_restart_block	arm_restart_block;
 };
 
 #define INIT_THREAD_INFO(tsk)						\