On Wednesday 9 October 2019 09:38:31 CEST kbuild test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git staging-testing > head: d49d1c76b96ebf39539e93d5ab7943a01ef70e4f > commit: 1a61af0f8cbecd1610c6fc380d0fb00f57fd43f2 [57/111] staging: wfx: allow to scan networks > > If you fix the issue, kindly add following tag > Reported-by: kbuild test robot <lkp@xxxxxxxxx> > Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > > New smatch warnings: > drivers/staging/wfx/scan.c:207 wfx_scan_work() warn: inconsistent returns 'sem:&wvif->scan.lock'. > Locked on: line 201 > Unlocked on: line 145 > > # https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git/commit/?id=1a61af0f8cbecd1610c6fc380d0fb00f57fd43f2 > git remote add staging https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git > git remote update staging > git checkout 1a61af0f8cbecd1610c6fc380d0fb00f57fd43f2 > vim +207 drivers/staging/wfx/scan.c > > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 116 void wfx_scan_work(struct work_struct *work) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 117 { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 118 struct wfx_vif *wvif = container_of(work, struct wfx_vif, scan.work); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 119 struct ieee80211_channel **it; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 120 struct wfx_scan_params scan = { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 121 .scan_req.scan_type.type = 0, /* Foreground */ > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 122 }; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 123 struct ieee80211_channel *first; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 124 int i; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 125 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 126 down(&wvif->scan.lock); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 127 mutex_lock(&wvif->wdev->conf_mutex); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 128 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 129 if (!wvif->scan.req || wvif->scan.curr == wvif->scan.end) { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 130 if (wvif->scan.output_power != wvif->wdev->output_power) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 131 hif_set_output_power(wvif, wvif->wdev->output_power * 10); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 132 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 133 if (wvif->scan.status < 0) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 134 dev_warn(wvif->wdev->dev, "scan failed\n"); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 135 else if (wvif->scan.req) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 136 dev_dbg(wvif->wdev->dev, "scan completed\n"); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 137 else > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 138 dev_dbg(wvif->wdev->dev, "scan canceled\n"); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 139 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 140 wvif->scan.req = NULL; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 141 wfx_tx_unlock(wvif->wdev); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 142 mutex_unlock(&wvif->wdev->conf_mutex); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 143 __ieee80211_scan_completed_compat(wvif->wdev->hw, wvif->scan.status ? 1 : 0); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 144 up(&wvif->scan.lock); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 145 return; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 146 } > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 147 first = *wvif->scan.curr; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 148 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 149 for (it = wvif->scan.curr + 1, i = 1; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 150 it != wvif->scan.end && i < HIF_API_MAX_NB_CHANNELS; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 151 ++it, ++i) { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 152 if ((*it)->band != first->band) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 153 break; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 154 if (((*it)->flags ^ first->flags) & > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 155 IEEE80211_CHAN_NO_IR) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 156 break; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 157 if (!(first->flags & IEEE80211_CHAN_NO_IR) && > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 158 (*it)->max_power != first->max_power) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 159 break; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 160 } > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 161 scan.scan_req.band = first->band; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 162 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 163 if (wvif->scan.req->no_cck) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 164 scan.scan_req.max_transmit_rate = API_RATE_INDEX_G_6MBPS; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 165 else > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 166 scan.scan_req.max_transmit_rate = API_RATE_INDEX_B_1MBPS; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 167 scan.scan_req.num_of_probe_requests = > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 168 (first->flags & IEEE80211_CHAN_NO_IR) ? 0 : 2; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 169 scan.scan_req.num_of_ssi_ds = wvif->scan.n_ssids; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 170 scan.ssids = &wvif->scan.ssids[0]; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 171 scan.scan_req.num_of_channels = it - wvif->scan.curr; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 172 scan.scan_req.probe_delay = 100; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 173 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 174 scan.ch = kcalloc(scan.scan_req.num_of_channels, sizeof(u8), GFP_KERNEL); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 175 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 176 if (!scan.ch) { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 177 wvif->scan.status = -ENOMEM; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 178 goto fail; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 179 } > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 180 for (i = 0; i < scan.scan_req.num_of_channels; ++i) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 181 scan.ch[i] = wvif->scan.curr[i]->hw_value; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 182 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 183 if (wvif->scan.curr[0]->flags & IEEE80211_CHAN_NO_IR) { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 184 scan.scan_req.min_channel_time = 50; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 185 scan.scan_req.max_channel_time = 150; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 186 } else { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 187 scan.scan_req.min_channel_time = 10; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 188 scan.scan_req.max_channel_time = 50; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 189 } > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 190 if (!(first->flags & IEEE80211_CHAN_NO_IR) && > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 191 wvif->scan.output_power != first->max_power) { > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 192 wvif->scan.output_power = first->max_power; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 193 hif_set_output_power(wvif, wvif->scan.output_power * 10); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 194 } > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 195 wvif->scan.status = wfx_scan_start(wvif, &scan); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 196 kfree(scan.ch); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 197 if (wvif->scan.status) > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 198 goto fail; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 199 wvif->scan.curr = it; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 200 mutex_unlock(&wvif->wdev->conf_mutex); > > Smatch says that we should have an: up(&wvif->scan.lock);. That seems > reasonable, but I'm not positive that it's correct. > > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 201 return; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 202 > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 203 fail: > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 204 wvif->scan.curr = wvif->scan.end; > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 205 mutex_unlock(&wvif->wdev->conf_mutex); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 206 up(&wvif->scan.lock); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 @207 schedule_work(&wvif->scan.work); > 1a61af0f8cbecd Jérôme Pouiller 2019-09-19 208 } wvif->scan.lock is unlocked when scan finish or timeout (in wfx_scan_complete()). So, the current behavior works (even if it could/should be written more cleanly). -- Jérôme Pouiller _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
