linux-kernel - Re: [PATCH] SPI: meson-spifc add missed calls to remove function

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sat, 24 Apr 2021 08:08:57 +0800
From:   Art Nikpal <email2tema@...il.com>
To:     Mark Brown <broonie@...nel.org>
Cc:     Neil Armstrong <narmstrong@...libre.com>,
        Kevin Hilman <khilman@...libre.com>, jbrunet@...libre.com,
        Martin Blumenstingl <martin.blumenstingl@...glemail.com>,
        dri-devel@...ts.freedesktop.org, linux-spi@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org,
        linux-amlogic@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Christian Hewitt <christianshewitt@...il.com>,
        Artem Lapkin <art@...das.com>, nick@...das.com,
        Gouwa Wang <gouwa@...das.com>
Subject: Re: [PATCH] SPI: meson-spifc add missed calls to remove function

> I would expect the driver to unregister the controller at the start of
> the remove function, suspend doesn't really make sense here

It's strange - But without spi_master_suspend i have randomly stucks
when i try unload this module - as was written before
i was test it (load/unload module in loop) and for me suspend make sense here

If anybody has another solution - or real problem not here - please
help to find the right way!

PS: i have another way for solve this problem (may be it can help us
fix problem in kernel)

# before unload module need
echo -n spi0.0 > /sys/bus/spi/drivers/spi-nor/unbind
# after unbind driver we can unload module without problem
rmmod spi_meson_spifc # can stuck without unbind driver before ...


On Fri, Apr 23, 2021 at 7:48 PM Mark Brown <broonie@...nel.org> wrote:
>
> On Fri, Apr 23, 2021 at 11:42:47AM +0800, Artem Lapkin wrote:
> > Problem: rmmod meson_gx_mmc - not stable without spi_master_suspend call
> > and we can get stuck when try unload this module
>
> > +++ b/drivers/spi/spi-meson-spifc.c
> > @@ -359,6 +359,7 @@ static int meson_spifc_remove(struct platform_device *pdev)
> >       struct spi_master *master = platform_get_drvdata(pdev);
> >       struct meson_spifc *spifc = spi_master_get_devdata(master);
> >
> > +     spi_master_suspend(master);
> >       pm_runtime_get_sync(&pdev->dev);
> >       clk_disable_unprepare(spifc->clk);
> >       pm_runtime_disable(&pdev->dev);
>
> I would expect the driver to unregister the controller at the start of
> the remove function, suspend doesn't really make sense here.