From: Jung Daehwan <dh10.jung@samsung.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>,
linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: usb: host: Reduce xhci_handshake timeout in xhci_reset
Date: Mon, 28 Jun 2021 15:55:53 +0900 [thread overview]
Message-ID: <20210628065553.GA83203@ubuntu> (raw)
In-Reply-To: <YNlxzj7KXG43Uyrp@kroah.com>
[-- Attachment #1: Type: text/plain, Size: 1799 bytes --]
On Mon, Jun 28, 2021 at 08:53:02AM +0200, Greg Kroah-Hartman wrote:
> On Mon, Jun 28, 2021 at 11:25:48AM +0900, Jung Daehwan wrote:
> > On Tue, Jun 22, 2021 at 09:56:20PM +0200, Greg Kroah-Hartman wrote:
> > > On Tue, Jun 22, 2021 at 08:24:56PM +0900, Daehwan Jung wrote:
> > > > It seems 10 secs timeout is too long in general case. A core would wait for
> > > > 10 secs without doing other task and it can be happended on every device.
> > >
> > > Only if the handshake does not come back sooner, right?
> >
> > Yes, right.
> >
> > > What is causing your device to timeout here?
> >
> > Host Controller doesn't respond handshake. I don't know why and I ask HW team
> > to debug it.
>
> Please work to fix your hardware, that feels like the root of the
> problem here. If you require the timeout for xhci_reset() to happen,
> then how do you know that the hardware really did reset properly in the
> reduced amount of time you just provided?
>
I continue fixing this issue with hardware engineer, but currently just
host controller can crash whole system and that's why I want to fix it.
How about adding some error logs in this situation for recognizing this issue?
We can add error log in xhci_stop as xhci_reset can returns error like below.
static void xhci_stop(struct usb_hcd *hcd)
{
u32 temp;
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+ int ret;
mutex_lock(&xhci->mutex);
@@ -733,6 +734,9 @@ static void xhci_stop(struct usb_hcd *hcd)
xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
xhci_halt(xhci);
xhci_reset(xhci);
+ if (ret)
+ xhci_err(xhci, "%s: Error while reset xhci Host controller - ret = %d\n"
+ , __func__, ret);
spin_unlock_irq(&xhci->lock);
> thanks,
>
> greg k-h
>
[-- Attachment #2: Type: text/plain, Size: 0 bytes --]
next prev parent reply other threads:[~2021-06-28 7:10 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20210622113915epcas2p284c61291fc9d83487f6dfebb65fd4e9b@epcas2p2.samsung.com>
2021-06-22 11:24 ` usb: host: Reduce xhci_handshake timeout in xhci_reset Daehwan Jung
2021-06-22 19:56 ` Greg Kroah-Hartman
2021-06-28 2:25 ` Jung Daehwan
2021-06-28 6:53 ` Greg Kroah-Hartman
2021-06-28 6:55 ` Jung Daehwan [this message]
2021-06-28 7:49 ` Mathias Nyman
2022-02-11 6:46 ` Pavan Kondeti
2022-02-11 7:43 ` Pavan Kondeti
2022-02-14 4:08 ` Pavan Kondeti
2022-02-14 5:22 ` Greg Kroah-Hartman
2022-02-14 5:52 ` Pavan Kondeti
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=20210628065553.GA83203@ubuntu \
--to=dh10.jung@samsung.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=mathias.nyman@intel.com \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).