staging: zram: Fix handling of incompressible pages

[Dan Carpenter]

Hello Nitin Gupta,

The patch c8f2f0db1d02: "staging: zram: Fix handling of
incompressible pages" from Oct 10, 2012, leads to the following
warning:
drivers/staging/zram/zram_drv.c:352 zram_bvec_write()
	 warn: 'uncmem' was already freed.

   338          ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen,
   339                                 zram->compress_workmem);
   340  
   341          kunmap_atomic(user_mem);
   342          if (is_partial_io(bvec))
   343                          kfree(uncmem);
                                ^^^^^^^^^^^^^^
freed here.  (Also indented too far).

   344  
   345          if (unlikely(ret != LZO_E_OK)) {
   346                  pr_err("Compression failed! err=%d\n", ret);
   347                  goto out;
   348          }
   349  
   350          if (unlikely(clen > max_zpage_size)) {
   351                  zram_stat_inc(&zram->stats.bad_compress);
   352                  src = uncmem;
                        ^^^^^^^^^^^^^
re-used.

   353                  clen = PAGE_SIZE;
   354          }

I haven't analyzed this at all, it may not be a bug.

regards,
dan carpenter