| Message ID | 1376402395-18775-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index d5515c0..8deaeb5 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -4552,7 +4552,8 @@ static void hub_events(void) hub->hdev->children[i - 1]; dev_dbg(hub_dev, "warm reset port %d\n", i); - if (!udev) { + if (!udev || !(portstatus & + USB_PORT_STAT_CONNECTION)) { status = hub_port_reset(hub, i, NULL, HUB_BH_RESET_TIME, true); @@ -4562,8 +4563,8 @@ static void hub_events(void) usb_lock_device(udev); status = usb_reset_device(udev); usb_unlock_device(udev); + connect_change = 0; } - connect_change = 0; } if (connect_change)
This is a note to let you know that I have just added a patch titled usb: core: don't try to reset_device() a port that got just to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From bdd0ccb77ce150945754b1de5cc1583fcb7a1394 Mon Sep 17 00:00:00 2001 From: Julius Werner <jwerner@chromium.org> Date: Tue, 30 Jul 2013 19:51:20 -0700 Subject: [PATCH] usb: core: don't try to reset_device() a port that got just disconnected commit 481f2d4f89f87a0baa26147f323380e31cfa7c44 upstream. The USB hub driver's event handler contains a check to catch SuperSpeed devices that transitioned into the SS.Inactive state and tries to fix them with a reset. It decides whether to do a plain hub port reset or call the usb_reset_device() function based on whether there was a device attached to the port. However, there are device/hub combinations (found with a JetFlash Transcend mass storage stick (8564:1000) on the root hub of an Intel LynxPoint PCH) which can transition to the SS.Inactive state on disconnect (and stay there long enough for the host to notice). In this case, above-mentioned reset check will call usb_reset_device() on the stale device data structure. The kernel will send pointless LPM control messages to the no longer connected device address and can even cause several 5 second khubd stalls on some (buggy?) host controllers, before finally accepting the device's fate amongst a flurry of error messages. This patch makes the choice of reset dependent on the port status that has just been read from the hub in addition to the existence of an in-kernel data structure for the device, and only proceeds with the more extensive reset if both are valid. Signed-off-by: Julius Werner <jwerner@chromium.org> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/usb/core/hub.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) -- 1.8.3.2