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From: Dan Carpenter <dan.carpenter@oracle.com>
To: thgarnie@google.com
Cc: linux-mm@kvack.org
Subject: re: mm: reorganize SLAB freelist randomization
Date: Mon, 6 Jun 2016 22:52:28 +0300	[thread overview]
Message-ID: <20160606195228.GA27327@mwanda> (raw)

Hello Thomas Garnier,

The patch aded650eb82e: "mm: reorganize SLAB freelist randomization"
from Jun 5, 2016, leads to the following static checker warning:

	mm/slab_common.c:1160 freelist_randomize()
	warn: why is zero skipped 'i'

mm/slab_common.c
  1146  /* Randomize a generic freelist */
  1147  static void freelist_randomize(struct rnd_state *state, unsigned int *list,
  1148                          size_t count)
  1149  {
  1150          size_t i;
  1151          unsigned int rand;
  1152  
  1153          for (i = 0; i < count; i++)
  1154                  list[i] = i;
  1155  
  1156          /* Fisher-Yates shuffle */
  1157          for (i = count - 1; i > 0; i--) {

This looks like it should be i >= 0.

  1158                  rand = prandom_u32_state(state);
  1159                  rand %= (i + 1);
  1160                  swap(list[i], list[rand]);
  1161          }
  1162  }

regards,
dan carpenter

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             reply	other threads:[~2016-06-06 19:52 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-06 19:52 Dan Carpenter [this message]
2016-06-06 20:01 ` mm: reorganize SLAB freelist randomization Thomas Garnier
2016-06-06 20:11   ` Dan Carpenter
2016-06-06 20:12     ` Thomas Garnier

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