我的 Dell XPS 15 (haswell) 运行良好，直到最近更新。从那时起，我的 wifi 就无法使用（单击工具栏中的 wifi 图标时显示“设备未管理”）。甚至 USB 转以太网适配器似乎也无法使用。蓝牙至少可以“看到”周围的其他蓝牙设备......
输出dmesg (dmesg |grep iwl)：
[ 886.462459] iwlwifi 0000:06:00.0: irq 51 for MSI/MSI-X
[ 886.462561] iwlwifi 0000:06:00.0: Direct firmware load failed with error -2
[ 886.462562] iwlwifi 0000:06:00.0: Falling back to user helper
[ 886.463284] iwlwifi 0000:06:00.0: loaded firmware version 22.1.7.0 op_mode iwlmvm
[ 886.475345] iwlwifi 0000:06:00.0: Detected Intel(R) Dual Band Wireless AC 7260, REV=0x144
[ 886.475433] iwlwifi 0000:06:00.0: L1 Enabled; Disabling L0S
[ 886.475684] iwlwifi 0000:06:00.0: L1 Enabled; Disabling L0S
[ 886.689214] ieee80211 phy0: Selected rate control algorithm 'iwl-mvm-rs'
来自modinfo iwlwifi：
filename: /lib/modules/3.13.0-29- generic/kernel/drivers/net/wireless/iwlwifi/iwlwifi.ko
license: GPL
author: Copyright(c) 2003-2013 Intel Corporation <[email protected]>
version: in-tree:
description: Intel(R) Wireless WiFi driver for Linux
firmware: iwlwifi-100-5.ucode
firmware: iwlwifi-1000-5.ucode
firmware: iwlwifi-135-6.ucode
firmware: iwlwifi-105-6.ucode
firmware: iwlwifi-2030-6.ucode
firmware: iwlwifi-2000-6.ucode
firmware: iwlwifi-5150-2.ucode
firmware: iwlwifi-5000-5.ucode
firmware: iwlwifi-6000g2b-6.ucode
firmware: iwlwifi-6000g2a-5.ucode
firmware: iwlwifi-6050-5.ucode
firmware: iwlwifi-6000-4.ucode
firmware: iwlwifi-3160-7.ucode
firmware: iwlwifi-7260-7.ucode
srcversion: 1E6912E109D5A43B310FB34
alias: pci:v00008086d0000095Asv*sd00005490bc*sc*i*
(a pack of lines of kind "alias: pci:xxxxx...." that I guess are not helpful)
alias: pci:v00008086d0000095Bsv*sd00005290bc*sc*i*
depends: cfg80211
intree: Y
vermagic: 3.13.0-29-generic SMP mod_unload modversions
signer: Magrathea: Glacier signing key
sig_key: 66:02:CB:36:F1:31:3B:EA:01:C4:BD:A9:65:67:CF:A7:23:C9:70:D8
sig_hashalgo: sha512
parm: swcrypto:using crypto in software (default 0 [hardware]) (int)
parm: 11n_disable:disable 11n functionality, bitmap: 1: full, 2: disable agg TX, 4: disable agg RX, 8 enable agg TX (uint)
parm: amsdu_size_8K:enable 8K amsdu size (default 0) (int)
parm: fw_restart:restart firmware in case of error (default true) (bool)
parm: antenna_coupling:specify antenna coupling in dB (defualt: 0 dB) (int)
parm: wd_disable:Disable stuck queue watchdog timer 0=system default, 1=disable, 2=enable (default: 0) (int)
parm: nvm_file:NVM file name (charp)
parm: bt_coex_active:enable wifi/bt co-exist (default: enable) (bool)
parm: led_mode:0=system default, 1=On(RF On)/Off(RF Off), 2=blinking, 3=Off (default: 0) (int)
parm: power_save:enable WiFi power management (default: disable) (bool)
parm: power_level:default power save level (range from 1 - 5, default: 1) (int)
我下载了最新版本的iwlwifi固件：
git clone git://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git
复制iwlwifi-3160-9.ucode iwlwifi-7260-9.ucode iwlwifi-7265-9.ucode到/lib/firmware并重新启动
但你可以想象，它并没有帮助。
更新＃1：
并将文件复制到/lib/firmware。
用 modprobe 重新加载之后，似乎没问题：
[ 14.761283] iwlwifi 0000:06:00.0: enabling device (0000 -> 0002)
[ 14.761472] iwlwifi 0000:06:00.0: irq 51 for MSI/MSI-X
[ 14.772478] iwlwifi 0000:06:00.0: loaded firmware version 22.15.8.0 op_mode iwlmvm
[ 14.800274] iwlwifi 0000:06:00.0: Detected Intel(R) Dual Band Wireless AC 7260, REV=0x144
[ 14.800349] iwlwifi 0000:06:00.0: L1 Enabled; Disabling L0S
[ 14.800657] iwlwifi 0000:06:00.0: L1 Enabled; Disabling L0S
[ 15.007048] ieee80211 phy0: Selected rate control algorithm 'iwl-mvm-rs'
但是，点击工具栏中的wifi仍然显示“设备未管理”。
有什么线索吗？
答案1
看过之后此主题和此主题在 Ubuntu 论坛上，我找到了我的问题的解决方案：
我把这一部分的最后一个参数/etc/NetworkManager/NetworkManager.conf从false改为true
[main]
plugins=ifupdown,keyfile,ofono
dns=dnsmasq
[ifupdown]
managed=**true**
并从中删除了整个部分/etc/network/interfaces：
iface br0 inet dhcp
bridge_ports eth0 wlan0
bridge_stp on
bridge_fd 0
我不确定这些参数是如何弄乱的 - 也许是因为我正在使用 KVM 网络参数，试图创建桥接连接。
无论如何，问题解决了。