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)                                           \