| Message ID | 1458211740-6875-1-git-send-email-mohammed@qca.qualcomm.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
Hi Michal / Kalle, > > On Thu, Mar 17, 2016 at 12:35:00PM +0100, Michal Kazior wrote: > > On 17 March 2016 at 12:20, Mohammed Shafi Shajakhan > > <mohammed@codeaurora.org> wrote: > > > Hi Michal, > > > > > > On Thu, Mar 17, 2016 at 12:12:31PM +0100, Michal Kazior wrote: > > >> On 17 March 2016 at 11:48, Mohammed Shafi Shajakhan > > >> <mohammed@qti.qualcomm.com> wrote: > > >> [...] > > >> > +void ath10k_sta_statistics(struct ieee80211_hw *hw, struct ieee80211_vif *vif, > > >> > + struct ieee80211_sta *sta, > > >> > + struct station_info *sinfo) > > >> > +{ > > >> > + struct ath10k_sta *arsta = (struct ath10k_sta *)sta->drv_priv; > > >> > + struct ath10k *ar = arsta->arvif->ar; > > >> > + > > >> > + mutex_lock(&ar->conf_mutex); > > >> > + > > >> > + if (ar->state != ATH10K_STATE_ON && > > >> > + ar->state != ATH10K_STATE_RESTARTED) > > >> > + goto out; > > >> > > >> Do you really need mutex and ar->state check in this function? > > >> > > > > > > [shafi] By default peer stats will be disabled, we are enabling this by debugfs > > > (hw-restart) so i thought these checks are needed , please advise .. Do you say > > > they will be never hit > > > > Hmm.. I think mac80211 shouldn't call sta_statistics() before > > sta_state() during recovery (it makes no sense). In practice I think > > this isn't enforced in which case it's a mac80211 bug. > > [shafi] sure i will check this. If the hardware is restarting there should > be no stations connected and station related info. [shafi] I did not see any checks in mac80211 to prevent this (may be i missed something), but i did remove the checks and tested it, could not find warnings, crashes (or) garbage values, so is it safer to remove (unless we find some issue with this) ?, please suggest Michal. i was doing this parallely in two terminals a) while true do cat rx_stats | grep duration -A 2 done b) /sys/kernel/debug/ieee80211/phy0/ath10k# echo 1 > peer_stats /sys/kernel/debug/ieee80211/phy0/ath10k# echo 0 > peer_stats (or) /sys/kernel/debug/ieee80211/phy0/ath10k# echo hw-restart > simulate_fw_crash > > > > > Anyway, this isn't much of a problem now. You only read out u64 from > > `arsta` (sta->drv_priv). Even if it's uninitialized/undefined there's > > no way for you to crash the system (it's not a list, spinlock or any > > other complex data structure). Worst case userspace will get garbage > > rx_duration value if it happens to get_station() while hw-restart is > > ongoing. > > [shafi] will check this .. [shafi] agree though i could not see any checks in mac80211 to prevent sta_set_sinfo (or check for the station state), i did not see any issues in my testing > > > > > It'd be good to verify this is actually a problem and - assuming you > > want to guarantee correct readouts at all times - to fix the problem > > in mac80211. > > > [shafi] ok, sure [shafi] I really don't have a deeper understanding of mac80211 code, i need to go through it thoroughly if i need to have checks for this if they were not already there. regards, shafi
diff --git a/drivers/net/wireless/ath/ath10k/debug.h b/drivers/net/wireless/ath/ath10k/debug.h index 6206edd..01c500f 100644 --- a/drivers/net/wireless/ath/ath10k/debug.h +++ b/drivers/net/wireless/ath/ath10k/debug.h @@ -155,6 +155,10 @@ ath10k_debug_get_new_fw_crash_data(struct ath10k *ar) void ath10k_sta_add_debugfs(struct ieee80211_hw *hw, struct ieee80211_vif *vif, struct ieee80211_sta *sta, struct dentry *dir); void ath10k_sta_update_rx_duration(struct ath10k *ar, struct list_head *peer); +void ath10k_sta_statistics(struct ieee80211_hw *hw, struct ieee80211_vif *vif, + struct ieee80211_sta *sta, + struct station_info *sinfo); + #else static inline void ath10k_sta_update_rx_duration(struct ath10k *ar, struct list_head *peer) diff --git a/drivers/net/wireless/ath/ath10k/debugfs_sta.c b/drivers/net/wireless/ath/ath10k/debugfs_sta.c index 67ef75b..4c459f2 100644 --- a/drivers/net/wireless/ath/ath10k/debugfs_sta.c +++ b/drivers/net/wireless/ath/ath10k/debugfs_sta.c @@ -35,6 +35,28 @@ void ath10k_sta_update_rx_duration(struct ath10k *ar, struct list_head *head) rcu_read_unlock(); } +void ath10k_sta_statistics(struct ieee80211_hw *hw, struct ieee80211_vif *vif, + struct ieee80211_sta *sta, + struct station_info *sinfo) +{ + struct ath10k_sta *arsta = (struct ath10k_sta *)sta->drv_priv; + struct ath10k *ar = arsta->arvif->ar; + + mutex_lock(&ar->conf_mutex); + + if (ar->state != ATH10K_STATE_ON && + ar->state != ATH10K_STATE_RESTARTED) + goto out; + + if (!ath10k_peer_stats_enabled(ar)) + goto out; + + sinfo->rx_duration = arsta->rx_duration; + sinfo->filled |= 1ULL << NL80211_STA_INFO_RX_DURATION; +out: + mutex_unlock(&ar->conf_mutex); +} + static ssize_t ath10k_dbg_sta_read_aggr_mode(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c index d5ef201..69a1dcf 100644 --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -6852,6 +6852,7 @@ static const struct ieee80211_ops ath10k_ops = { #endif #ifdef CONFIG_MAC80211_DEBUGFS .sta_add_debugfs = ath10k_sta_add_debugfs, + .sta_statistics = ath10k_sta_statistics, #endif };