我的笔记本电脑最近开始不时无法挂起到 RAM。我已经完全重新安装了 Kubuntu 14.04（可靠），但错误仍会间歇性地出现。
看看/var/log/pm-powersave.log我看到的条目如下：
Running hook /usr/lib/pm-utils/power.d/pci_devices false:
Setting Host Bridge 0000:00:00.0 to on
/usr/lib/pm-utils/power.d/pci_devices: 30: /usr/lib/pm-utils/power.d/pci_devices: cannot create /sys/bus/pci/devices/0000:00:00.0/powe
r/control: Read-only file system
Setting Ethernet device 0000:00:19.0 to on
/usr/lib/pm-utils/power.d/pci_devices: 18: /usr/lib/pm-utils/power.d/pci_devices: cannot create /sys/bus/pci/devices/0000:00:19.0/powe
r/control: Read-only file system
Setting Audio device 0000:00:1b.0 to on
/usr/lib/pm-utils/power.d/pci_devices: 26: /usr/lib/pm-utils/power.d/pci_devices: cannot create /sys/bus/pci/devices/0000:00:1b.0/powe
r/control: Read-only file system
Setting card reader device 0000:02:00.0 to on
/usr/lib/pm-utils/power.d/pci_devices: 38: /usr/lib/pm-utils/power.d/pci_devices: cannot create /sys/bus/pci/devices/0000:02:00.0/powe
r/control: Read-only file system
Setting Wireless device 0000:03:00.0 to on
/usr/lib/pm-utils/power.d/pci_devices: 22: /usr/lib/pm-utils/power.d/pci_devices: cannot create /sys/bus/pci/devices/0000:03:00.0/powe
r/control: Read-only file system
/usr/lib/pm-utils/power.d/pci_devices false: success.
mount然而显示了这一点：
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
我没有发现机器在挂起和不挂起时运行的任何不同。也没有插入任何新程序。
什么原因可能导致它报告只读 sys 文件系统？ 有什么方法可以尝试重新挂载，/sys以便可能再次将其标记为读/写？