Return-path: Received: from mail-gw1-out.broadcom.com ([216.31.210.62]:51406 "EHLO mail-gw1-out.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754187AbbIRUI0 (ORCPT ); Fri, 18 Sep 2015 16:08:26 -0400 From: Arend van Spriel To: Kalle Valo CC: linux-wireless , Hante Meuleman , Arend van Spriel Subject: [PATCH 13/16] brcmfmac: Fix race condition bug when deleting p2p interface. Date: Fri, 18 Sep 2015 22:08:16 +0200 Message-ID: <1442606899-31872-14-git-send-email-arend@broadcom.com> (sfid-20150918_220844_567426_ABF7557A) In-Reply-To: <1442606899-31872-1-git-send-email-arend@broadcom.com> References: <1442606899-31872-1-git-send-email-arend@broadcom.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Hante Meuleman 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 --- 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 76e4771..fda726c 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); -- 1.9.1