Blackfin: access_ok: permit L1 stack

When apps run with their stack in L1, some system calls might be made
where a buffer is in the stack as an argument.  So make sure the core
Blackfin access code does not reject this memory location.

Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c
index c86a3ed5f48f..cd0c090ebc54 100644
--- a/arch/blackfin/kernel/process.c
+++ b/arch/blackfin/kernel/process.c
@@ -493,6 +493,11 @@ int _access_ok(unsigned long addr, unsigned long size)
                 return 1;
 #endif
 
+#ifndef CONFIG_EXCEPTION_L1_SCRATCH
+        if (in_mem_const(addr, size, (unsigned long)l1_stack_base, l1_stack_len))
+                return 1;
+#endif
+
         aret = in_async(addr, size);
         if (aret < 2)
                 return aret;