kernel/linux.git/drivers/usb/core, branch linux-2.6.18.y

[PATCH] usbfs: private mutex for open, release, and remove

2006-11-04T01:33:50+00:00

The usbfs code doesn't provide sufficient mutual exclusion among open, release, and remove. Release vs. remove is okay because they both acquire the device lock, but open is not exclusive with either one. All three routines modify the udev->filelist linked list, so they must not run concurrently. Apparently someone gave this a minimum amount of thought in the past by explicitly acquiring the BKL at the start of the usbdev_open routine. Oddly enough, there's a comment pointing out that locking is unnecessary because chrdev_open already has acquired the BKL. But this ignores the point that the files in /proc/bus/usb/* are not char device files; they are regular files and so they don't get any special locking. Furthermore it's necessary to acquire the same lock in the release and remove routines, which the code does not do. Yet another problem arises because the same file_operations structure is accessible through both the /proc/bus/usb/* and /dev/usb/usbdev* file nodes. Even when one of them has been removed, it's still possible for userspace to open the other. So simple locking around the individual remove routines is insufficient; we need to lock the entire usb_notify_remove_device notifier chain. Rather than rely on the BKL, this patch (as723) introduces a new private mutex for the purpose. Holding the BKL while invoking a notifier chain doesn't seem like a good idea. Cc: Dave Jones [https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=212952] Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chris Wright

Revert "[PATCH] USB: move usb_device_class class devices to be real devices"

2006-08-02T23:52:10+00:00

This reverts c182274ffe1277f4e7c564719a696a37cacf74ea commit because it required a newer version of udev to work properly than what is currently documented in Documentation/Changes. Cc: Kay Sievers Signed-off-by: Greg Kroah-Hartman

Revert "[PATCH] USB: convert usb class devices to real devices"

2006-08-02T23:49:37+00:00

This reverts bd00949647ddcea47ce4ea8bb2cfcfc98ebf9f2a commit because it required a newer version of udev to work properly than what is currently documented in Documentation/Changes. Signed-off-by: Greg Kroah-Hartman

[PATCH] USB: remove devfs information from Kconfig

2006-07-12T23:03:23+00:00

Devfs is gone. We can remove that information. Signed-off-by: Michal Piotrowski Signed-off-by: Greg Kroah-Hartman

[PATCH] usbcore: fixes for hub_port_resume

2006-07-12T23:03:22+00:00

This patch (as731) makes a couple of small fixes to the hub_port_resume routine: Don't return status >= 0 when an error occurs; Clear the port-change-suspend status indicator after resuming a device. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

[PATCH] USB hub: don't return status > 0 from resume

2006-07-12T23:03:22+00:00

finish_device_resume() in the hub driver isn't careful always to return a negative code in all the error pathways. It also doesn't return 0 in all the success pathways. This patch (as724) fixes the behavior. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

[PATCH] usbfs: use the correct signal number for disconnection

2006-07-12T23:03:21+00:00

usbfs stores the wrong signal number in the siginfo structure used for notifying user programs about device disconnect. This patch (as726) fixes it. From: Zoran Marceta Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

[PATCH] lockdep: annotate USBFS

2006-07-03T22:27:08+00:00

In usbfs's fs_remove_file() function, the aim is to remove a file or directory from usbfs. This is done by first taking the i_mutex of the parent directory of this file/dir via mutex_lock(&parent->d_inode->i_mutex); and then to call either usbfs_rmdir() for a directory or usbfs_unlink() for a file. Both these functions then take the i_mutex for the to-be-removed object themselves: mutex_lock(&inode->i_mutex); This is a classical parent->child locking order relationship that the VFS uses all over the place; the VFS locking rule is "you need to take the parent first". This patch annotates the usbfs code to make this explicit and thus informs the lockdep code that those two locks indeed have this relationship. The rules for unlink that we already use in the VFS for unlink are to use I_MUTEX_PARENT for the parent directory, and a normal mutex for the file itself; this patch follows that convention. Has no effect on non-lockdep kernels. Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] lockdep: annotate i_mutex

2006-07-03T22:27:06+00:00

Teach special (recursive) locking code to the lock validator. Has no effect on non-lockdep kernels. Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] irq-flags: usb: Use the new IRQF_ constants

2006-07-02T20:58:53+00:00

Signed-off-by: Thomas Gleixner Cc: Ingo Molnar Cc: "David S. Miller" Cc: Benjamin Herrenschmidt Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds