<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hey,<div class=""><br class=""></div><div class="">Not sure if related, but I have been struggling with a similar, seemingly USB related issue on 4.19.xx. In my case the modem completely disappears and only a reboot of the host system will fix it. I am documenting it here: <a href="https://forum.openwrt.org/t/ipq4019-xhci-hcd-host-died/47237" class="">https://forum.openwrt.org/t/ipq4019-xhci-hcd-host-died/47237</a><div class=""><pre class=""><code class="">[566389.792034] usb 1-1: USB disconnect, device number 2 [566394.603851] cdc_mbim 1-1:1.12: Tx URB error: -19 [566394.829730] xhci-hcd xhci-hcd.0.auto: xHCI host not responding to stop endpoint command. [566394.846083] xhci-hcd xhci-hcd.0.auto: Host halt failed, -110 [566394.846315] xhci-hcd xhci-hcd.0.auto: xHCI host controller not responding, assume dead [566394.851573] xhci-hcd xhci-hcd.0.auto: HC died; cleaning up [566394.862108] qcserial ttyUSB0: Qualcomm USB modem converter now disconnected from ttyUSB0 [566394.865473] qcserial 1-1:1.0: device disconnected [566394.880516] qcserial ttyUSB1: Qualcomm USB modem converter now disconnected from ttyUSB1 [566394.881892] qcserial 1-1:1.3: device disconnected [566394.892850] cdc_mbim 1-1:1.12 wwan0: unregister 'cdc_mbim' usb-xhci-hcd.0.auto-1, CDC MBIM [566394.897722] failed to kill vid 0081/0 for device wwan0</code></pre><div class=""><br class=""></div></div><div class="">Best,</div><div class="">Nicholas</div></div></body></html>