(2010/06/24 7:46), Greg KH wrote:
On Wed, Jun 23, 2010 at 04:04:10PM +0900, Kenji Kaneshige wrote:I encountered the problem that /proc/bus/pci/XX/YY is not removed even after the corresponding device is hot-removed, if the file is still being opened. In addtion, accessing this file in this situation causes kernel panic (see below). Becasue the pci_proc_detach_device() doesn't call remove_proc_entry() if struct proc_dir_entry->count> 1, access to /proc/bus/pci/XX/YY would refer to struct pci_dev that was already freed. Though I don't know why the check for proc_dir_entry->count was added, I don't think it is needed. Removing this check fixes the problem. Steps to reproduce ------------------ # cd /sys/bus/pci/slots/2/ # PROC_BUS_PCI_FILE=/proc/bus/pci/`awk -F: '{print $2"/"$3}'< address`.0 # sleep 10000< $PROC_BUS_PCI_FILE& # echo 0> power # while true; do cat $PROC_BUS_PCI_FILE> /dev/null; doneThose last 2 lines only work as root, right?
In fact, only "echo 0 > power"s needs root privilege. The last line works as non root. Thank you very much for review. Thanks, Kenji Kaneshige -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
