LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Marcel Holtmann <marcel@holtmann.org>
To: Salah Triki <salah.triki@gmail.com>
Cc: Johan Hedberg <johan.hedberg@gmail.com>,
	Luiz Augusto von Dentz <luiz.dentz@gmail.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	BlueZ <linux-bluetooth@vger.kernel.org>,
	open list <linux-kernel@vger.kernel.org>,
	Alan Stern <stern@rowland.harvard.edu>,
	Oliver Neukum <oliver@neukum.org>
Subject: Re: [PATCH v2] bluetooth: bcm203x: update the reference count of udev
Date: Sun, 1 Aug 2021 20:01:06 +0200	[thread overview]
Message-ID: <9B2209B6-D371-432B-A3F5-F1CD7C7967A3@holtmann.org> (raw)
In-Reply-To: <20210731154102.GA908767@pc>

Hi Salah,

> Use usb_get_dev() to increment the reference count of the usb device
> structure in order to avoid releasing the structure while it is still in
> use. And use usb_put_dev() to decrement the reference count and thus,
> when it will be equal to 0 the structure will be released.
> 
> Signed-off-by: Salah Triki <salah.triki@gmail.com>
> ---
> Change since v1:
> 	Modification of the description
> 
> drivers/bluetooth/bcm203x.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/bluetooth/bcm203x.c b/drivers/bluetooth/bcm203x.c
> index e667933c3d70..547d35425d70 100644
> --- a/drivers/bluetooth/bcm203x.c
> +++ b/drivers/bluetooth/bcm203x.c
> @@ -166,7 +166,7 @@ static int bcm203x_probe(struct usb_interface *intf, const struct usb_device_id
> 	if (!data)
> 		return -ENOMEM;
> 
> -	data->udev  = udev;
> +	data->udev  = usb_get_dev(udev);
> 	data->state = BCM203X_LOAD_MINIDRV;
> 
> 	data->urb = usb_alloc_urb(0, GFP_KERNEL);
> @@ -244,6 +244,8 @@ static void bcm203x_disconnect(struct usb_interface *intf)
> 
> 	usb_set_intfdata(intf, NULL);
> 
> +	usb_put_dev(data->udev);
> +
> 	usb_free_urb(data->urb);
> 	kfree(data->fw_data);
> 	kfree(data->buffer);

I do not understand this. If this is something broken, then it is broken in
btusb.c as well and that driver is heavily used by all sorts of devices. So
we should have seen bug reports about this.

Regards

Marcel


  reply	other threads:[~2021-08-01 18:01 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-31 15:41 Salah Triki
2021-08-01 18:01 ` Marcel Holtmann [this message]
2021-08-02 19:34   ` Salah Triki
2021-08-02 20:16     ` Alan Stern

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=9B2209B6-D371-432B-A3F5-F1CD7C7967A3@holtmann.org \
    --to=marcel@holtmann.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=johan.hedberg@gmail.com \
    --cc=linux-bluetooth@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luiz.dentz@gmail.com \
    --cc=oliver@neukum.org \
    --cc=salah.triki@gmail.com \
    --cc=stern@rowland.harvard.edu \
    --subject='Re: [PATCH v2] bluetooth: bcm203x: update the reference count of udev' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).