From a2044d91d9d25a0e9e2abb43ca90cceee032f6ee Mon Sep 17 00:00:00 2001 From: Hante Meuleman Date: Fri, 18 Sep 2015 22:08:16 +0200 Subject: [PATCH] brcmfmac: Fix race condition bug when deleting p2p interface. When p2p device interface gets deleted by deinitialising discovery it will result in an event which removes the interface, but that is also done by delete p2p interface code. This results in race condition which sometimes results in lockup/crash. With this patch the delete device interface will wait for the event (with timeout) removing the possible race condition. Also on the stop device call from cfg80211 the deinitialisation of the discovery device should be avoided as it can result in a similar situation. Reviewed-by: Arend Van Spriel Reviewed-by: Pieter-Paul Giesberts Signed-off-by: Hante Meuleman Signed-off-by: Arend van Spriel Signed-off-by: Kalle Valo --- drivers/net/wireless/brcm80211/brcmfmac/p2p.c | 22 ++++++++++++------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/brcm80211/brcmfmac/p2p.c b/drivers/net/wireless/brcm80211/brcmfmac/p2p.c index 76e477109e6d..fda726c8e7ab 100644 --- a/drivers/net/wireless/brcm80211/brcmfmac/p2p.c +++ b/drivers/net/wireless/brcm80211/brcmfmac/p2p.c @@ -2241,6 +2241,7 @@ int brcmf_p2p_del_vif(struct wiphy *wiphy, struct wireless_dev *wdev) brcmf_dbg(TRACE, "delete P2P vif\n"); vif = container_of(wdev, struct brcmf_cfg80211_vif, wdev); + brcmf_cfg80211_arm_vif_event(cfg, vif); switch (vif->wdev.iftype) { case NL80211_IFTYPE_P2P_CLIENT: if (test_bit(BRCMF_VIF_STATUS_DISCONNECTING, &vif->sme_state)) @@ -2257,8 +2258,6 @@ int brcmf_p2p_del_vif(struct wiphy *wiphy, struct wireless_dev *wdev) return 0; brcmf_p2p_cancel_remain_on_channel(vif->ifp); brcmf_p2p_deinit_discovery(p2p); - brcmf_remove_interface(vif->ifp); - return 0; default: return -ENOTSUPP; } @@ -2270,10 +2269,11 @@ int brcmf_p2p_del_vif(struct wiphy *wiphy, struct wireless_dev *wdev) wait_for_completion_timeout(&cfg->vif_disabled, msecs_to_jiffies(500)); - brcmf_vif_clear_mgmt_ies(vif); - - brcmf_cfg80211_arm_vif_event(cfg, vif); - err = brcmf_p2p_release_p2p_if(vif); + err = 0; + if (vif->wdev.iftype != NL80211_IFTYPE_P2P_DEVICE) { + brcmf_vif_clear_mgmt_ies(vif); + err = brcmf_p2p_release_p2p_if(vif); + } if (!err) { /* wait for firmware event */ err = brcmf_cfg80211_wait_vif_event_timeout(cfg, BRCMF_E_IF_DEL, @@ -2283,8 +2283,12 @@ int brcmf_p2p_del_vif(struct wiphy *wiphy, struct wireless_dev *wdev) else err = 0; } + if (err) + brcmf_remove_interface(vif->ifp); + brcmf_cfg80211_arm_vif_event(cfg, NULL); - p2p->bss_idx[P2PAPI_BSSCFG_CONNECTION].vif = NULL; + if (vif->wdev.iftype != NL80211_IFTYPE_P2P_DEVICE) + p2p->bss_idx[P2PAPI_BSSCFG_CONNECTION].vif = NULL; return err; } @@ -2333,7 +2337,9 @@ void brcmf_p2p_stop_device(struct wiphy *wiphy, struct wireless_dev *wdev) */ if (p2p->bss_idx[P2PAPI_BSSCFG_DEVICE].vif == vif) { mutex_lock(&cfg->usr_sync); - (void)brcmf_p2p_deinit_discovery(p2p); + /* Set the discovery state to SCAN */ + (void)brcmf_p2p_set_discover_state(vif->ifp, + WL_P2P_DISC_ST_SCAN, 0, 0); brcmf_abort_scanning(cfg); clear_bit(BRCMF_VIF_STATUS_READY, &vif->sme_state); mutex_unlock(&cfg->usr_sync); -- 2.20.1