Sparse noticed a lock imbalance in read_from_buf(). Further inspection shows
that the lock should not be held when the function exits.
This adds a spin_unlock_irqrestore(), so that every exit path of the
read_from_buf() function is consistent. The unlock was missing on an error
path.
Signed-off-by: Ira W. Snyder <devel@irasnyder.com>
Signed-off-by: Hans J. Koch <koch@hjk-az.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
        if (rd_blocks > s->block_count)
                rd_blocks = s->block_count;
 
-       if (!rd_blocks)
+       if (!rd_blocks) {
+               spin_unlock_irqrestore(&s->lock, flags);
                return;
+       }
 
        for (i = 0; i < rd_blocks; i++) {
                if (block_to_user_buf(s, buf_ptr)) {