i386: fix file_read_actor() and pipe_read() for original i386 systems

[linux.git] / arch / i386 / lib / usercopy.c

diff --git a/arch/i386/lib/usercopy.c b/arch/i386/lib/usercopy.c
index 4cf981d70f45b621acbce1df4bf7097d27b6d85d..20910daa53af6dfd35ae3e845ae165a1b979fd8a 100644 (file)
--- a/arch/i386/lib/usercopy.c
+++ b/arch/i386/lib/usercopy.c
@@ -10,6 +10,7 @@
 #include <linux/highmem.h>
 #include <linux/blkdev.h>
 #include <linux/module.h>
+#include <linux/interrupt.h>
 #include <asm/uaccess.h>
 #include <asm/mmx.h>
 
@@ -522,6 +523,14 @@ unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned long
 #ifndef CONFIG_X86_WP_WORKS_OK
        if (unlikely(boot_cpu_data.wp_works_ok == 0) &&
                        ((unsigned long )to) < TASK_SIZE) {
+               /*
+                * When we are in an atomic section (see
+                * mm/filemap.c:file_read_actor), return the full
+                * length to take the slow path.
+                */
+               if (in_atomic())
+                       return n;
+
                /* 
                 * CPU does not honor the WP bit when writing
                 * from supervisory mode, and due to preemption or SMP,