Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/arch/riscv/include/asm/futex.h b/arch/riscv/include/asm/futex.h
index 4ad6409..1b00bad 100644
--- a/arch/riscv/include/asm/futex.h
+++ b/arch/riscv/include/asm/futex.h
@@ -4,14 +4,20 @@
  * Copyright (c) 2018  Jim Wilson (jimw@sifive.com)
  */
 
-#ifndef _ASM_FUTEX_H
-#define _ASM_FUTEX_H
+#ifndef _ASM_RISCV_FUTEX_H
+#define _ASM_RISCV_FUTEX_H
 
 #include <linux/futex.h>
 #include <linux/uaccess.h>
 #include <linux/errno.h>
 #include <asm/asm.h>
 
+/* We don't even really need the extable code, but for now keep it simple */
+#ifndef CONFIG_MMU
+#define __enable_user_access()		do { } while (0)
+#define __disable_user_access()		do { } while (0)
+#endif
+
 #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg)	\
 {								\
 	uintptr_t tmp;						\
@@ -40,7 +46,8 @@
 {
 	int oldval = 0, ret = 0;
 
-	pagefault_disable();
+	if (!access_ok(uaddr, sizeof(u32)))
+		return -EFAULT;
 
 	switch (op) {
 	case FUTEX_OP_SET:
@@ -67,8 +74,6 @@
 		ret = -ENOSYS;
 	}
 
-	pagefault_enable();
-
 	if (!ret)
 		*oval = oldval;
 
@@ -112,4 +117,4 @@
 	return ret;
 }
 
-#endif /* _ASM_FUTEX_H */
+#endif /* _ASM_RISCV_FUTEX_H */