From: Greg KH <gregkh@linuxfoundation.org>
To: David Heinzelmann <heinzelmann.david@gmail.com>
Cc: stern@rowland.harvard.edu, linux-usb@vger.kernel.org
Subject: Re: [PATCH v4] usb: hub: Check device descriptor before resusciation
Date: Tue, 8 Oct 2019 14:55:46 +0200 [thread overview]
Message-ID: <20191008125546.GA2846493@kroah.com> (raw)
In-Reply-To: <20191008080901.17628-1-heinzelmann.david@gmail.com>
On Tue, Oct 08, 2019 at 10:09:01AM +0200, David Heinzelmann wrote:
> If a device connected to an xHCI host controller disconnects from the USB bus
> and then reconnects, e.g. triggered by a firmware update, then the host
> controller automatically activates the connection and the port is enabled. The
> implementation of hub_port_connect_change() assumes that if the port is
> enabled then nothing has changed. There is no check if the USB descriptors
> have changed. As a result, the kernel's internal copy of the descriptors ends
> up being incorrect and the device doesn't work properly anymore.
>
> The solution to the problem is for hub_port_connect_change() always to
> check whether the device's descriptors have changed before resuscitating
> an enabled port.
>
> Signed-off-by: David Heinzelmann <heinzelmann.david@gmail.com>
> ---
> Changes in v4:
> - changed commit description
> Changes in v3:
> - changed commit message and description
> - fix code style
> Changes in v2:
> - fix logic error to handle return code from usb_get_device_descriptor()
> properly
> - fix line endings
> ---
> drivers/usb/core/hub.c | 196 +++++++++++++++++++++++------------------
> 1 file changed, 111 insertions(+), 85 deletions(-)
What happened to Alan's ack?
v5?
thanks,
greg k-h
next prev parent reply other threads:[~2019-10-08 12:55 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-20 10:36 [PATCH] Check for changed device descriptors when a connection-change occurs before validating the connection David Heinzelmann
2019-09-20 8:55 ` Greg KH
2019-09-20 13:17 ` David Heinzelmann
2019-09-20 12:15 ` Greg KH
2019-09-20 15:33 ` David Heinzelmann
2019-09-23 14:49 ` Alan Stern
2019-09-24 10:01 ` David Heinzelmann
2019-09-25 14:20 ` Alan Stern
2019-09-30 7:26 ` David Heinzelmann
2019-09-30 14:25 ` Alan Stern
2019-10-04 13:23 ` David Heinzelmann
2019-10-04 14:17 ` Alan Stern
2019-10-07 8:47 ` David Heinzelmann
2019-10-07 14:01 ` Alan Stern
2019-10-07 15:35 ` Greg KH
2019-10-08 8:09 ` [PATCH v4] usb: hub: Check device descriptor before resusciation David Heinzelmann
2019-10-08 12:55 ` Greg KH [this message]
2019-10-08 16:10 ` David Heinzelmann
2019-10-08 15:17 ` Greg KH
2019-10-09 4:46 ` [PATCH v5] " David Heinzelmann
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