From: Heiko Thiery <heiko.thiery@gmail.com>
To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Fugang Duan <fugang.duan@nxp.com>,
"David S . Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Richard Cochran <richardcochran@gmail.com>
Subject: Re: [PATCH v2 1/1] net: fec: ptp: avoid register access when ipg clock is disabled
Date: Fri, 26 Feb 2021 08:22:50 +0100 [thread overview]
Message-ID: <CAEyMn7aijecc6ai5YaaHFa1Y7u52v=KEga3nRKvXE3o-mCQLYA@mail.gmail.com> (raw)
In-Reply-To: <20210225211514.9115-1-heiko.thiery@gmail.com>
Hi all,
Am Do., 25. Feb. 2021 um 22:15 Uhr schrieb Heiko Thiery
<heiko.thiery@gmail.com>:
>
> When accessing the timecounter register on an i.MX8MQ the kernel hangs.
> This is only the case when the interface is down. This can be reproduced
> by reading with 'phc_ctrl eth0 get'.
>
> Like described in the change in 91c0d987a9788dcc5fe26baafd73bf9242b68900
> the igp clock is disabled when the interface is down and leads to a
> system hang.
>
> So we check if the ptp clock status before reading the timecounter
> register.
>
> Signed-off-by: Heiko Thiery <heiko.thiery@gmail.com>
Sorry for the noise. But just realized that I sent a v3 version of the
patch but forgot to update the subject line (still v2). Should I
resend it with the correct subject?
> ---
> v2:
> - add mutex (thanks to Richard)
>
> v3:
> I did a mistake and did not test properly
> - add parenteses
> - fix the used variable
>
> drivers/net/ethernet/freescale/fec_ptp.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c
> index 2e344aada4c6..1753807cbf97 100644
> --- a/drivers/net/ethernet/freescale/fec_ptp.c
> +++ b/drivers/net/ethernet/freescale/fec_ptp.c
> @@ -377,9 +377,16 @@ static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
> u64 ns;
> unsigned long flags;
>
> + mutex_lock(&adapter->ptp_clk_mutex);
> + /* Check the ptp clock */
> + if (!adapter->ptp_clk_on) {
> + mutex_unlock(&adapter->ptp_clk_mutex);
> + return -EINVAL;
> + }
> spin_lock_irqsave(&adapter->tmreg_lock, flags);
> ns = timecounter_read(&adapter->tc);
> spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
> + mutex_unlock(&adapter->ptp_clk_mutex);
>
> *ts = ns_to_timespec64(ns);
>
> --
> 2.30.0
>
next prev parent reply other threads:[~2021-02-26 7:24 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-25 21:15 [PATCH v2 1/1] net: fec: ptp: avoid register access when ipg clock is disabled Heiko Thiery
2021-02-26 7:22 ` Heiko Thiery [this message]
2021-02-26 15:23 ` Richard Cochran
2021-02-26 23:44 ` Jakub Kicinski
-- strict thread matches above, loose matches on Subject: below --
2021-02-25 20:55 Heiko Thiery
2021-02-25 22:34 ` kernel test robot
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='CAEyMn7aijecc6ai5YaaHFa1Y7u52v=KEga3nRKvXE3o-mCQLYA@mail.gmail.com' \
--to=heiko.thiery@gmail.com \
--cc=davem@davemloft.net \
--cc=fugang.duan@nxp.com \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=richardcochran@gmail.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).