batman-adv/patches/0004-batman-adv-Make-NC-capability-changes-atomic.patch

   1 From 586df9e2537b51c0df7ce99576c3cee1681b64de Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Linus=20L=C3=BCssing?= <linus.luessing@c0d3.blue>
   3 Date: Tue, 16 Jun 2015 17:10:23 +0200
   4 Subject: [PATCH 04/17] batman-adv: Make NC capability changes atomic
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   8
   9 Bitwise OR/AND assignments in C aren't guaranteed to be atomic. One
  10 OGM handler might undo the set/clear of a specific bit from another
  11 handler run in between.
  12
  13 Fix this by using the atomic set_bit()/clear_bit() functions.
  14
  15 Fixes: 7dd9d8992b0c ("batman-adv: tvlv - add network coding container")
  16 Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
  17 Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
  18 ---
  19  network-coding.c | 4 ++--
  20  1 file changed, 2 insertions(+), 2 deletions(-)
  21
  22 diff --git a/network-coding.c b/network-coding.c
  23 index 89e1d47..3ce493e 100644
  24 --- a/network-coding.c
  25 +++ b/network-coding.c
  26 @@ -105,9 +105,9 @@ static void batadv_nc_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
  27                                           uint16_t tvlv_value_len)
  28  {
  29         if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
  30 -               orig->capabilities &= ~BATADV_ORIG_CAPA_HAS_NC;
  31 +               clear_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
  32         else
  33 -               orig->capabilities |= BATADV_ORIG_CAPA_HAS_NC;
  34 +               set_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
  35  }
  36
  37  /**
  38 --
  39 2.1.4
  40