Date: Sun, 6 Sep 2009 18:50:29 +0200 (CEST) From: Stefan Richter Subject: firewire: core: fix race with parallel PCI device probe The config ROM buffer received from generate_config_rom is a globally shared static buffer. Extend the card_mutex protection in fw_add_card until after the config ROM was copied into the card driver's buffer. Otherwise, parallelized card driver probes may end up with ROM contents that were meant for a different card. firewire-ohci's card->driver->enable hook is safe to be called within the card_mutex. Furthermore, it is safe to reorder card_list update versus card enable, which simplifies the code a little. Signed-off-by: Stefan Richter --- drivers/firewire/core-card.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) Index: linux-2.6.31/drivers/firewire/core-card.c =================================================================== --- linux-2.6.31.orig/drivers/firewire/core-card.c +++ linux-2.6.31/drivers/firewire/core-card.c @@ -444,16 +444,13 @@ int fw_card_add(struct fw_card *card, card->guid = guid; mutex_lock(&card_mutex); - config_rom = generate_config_rom(card, &length); - list_add_tail(&card->link, &card_list); - mutex_unlock(&card_mutex); + config_rom = generate_config_rom(card, &length); ret = card->driver->enable(card, config_rom, length); - if (ret < 0) { - mutex_lock(&card_mutex); - list_del(&card->link); - mutex_unlock(&card_mutex); - } + if (ret == 0) + list_add_tail(&card->link, &card_list); + + mutex_unlock(&card_mutex); return ret; }