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Message-ID: <47735babf2f02ce85e9201df403bf3e1ec5579d6.camel@suse.com>
Subject: Re: disk revalidation updates and OOM
From:   Martin Wilck <mwilck@suse.com>
To:     He Zhe <zhe.he@windriver.com>, Christoph Hellwig <hch@lst.de>,
        jack@suse.cz, Jens Axboe <axboe@kernel.dk>,
        viro@zeniv.linux.org.uk, bvanassche@acm.org, keith.busch@intel.com,
        tglx@linutronix.de, yuyufen@huawei.com,
        linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Wed, 11 Mar 2020 16:11:28 +0100
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         <209f06496c1ef56b52b0ec67c503838e402c8911.camel@suse.com>
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On Wed, 2020-03-11 at 11:29 +0100, Martin Wilck wrote:
> On Mon, 2020-03-02 at 11:55 +0800, He Zhe wrote:
> > Hi,
> > 
> > Since the following commit
> > https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/commit/?h=for-5.5/disk-revalidate&id=6917d0689993f46d97d40dd66c601d0fd5b1dbdd
> > until now(v5.6-rc4),
> > 
> > If we start udisksd service of systemd(v244), systemd-udevd will
> > scan
> > /dev/hdc
> > (the cdrom device created by default in qemu(v4.2.0)). systemd-
> > udevd
> > will
> > endlessly run and cause OOM.
> 
> I've tried to reproduce this, but so far I haven't been able to.
> Perhaps because the distro 5.5.7 kernel I've tried (which contains
> the
> offending commit 142fe8f) has no IDE support - the qemu IDE CD shows
> up
> as sr0, with the ata_piix driver. I have systemd-udevd 244. Enabling
> udisksd makes no difference, the system runs stably. ISO images can
> be "ejected" and loaded, single uevents are received and processed.
> 
> Does this happen for you if you use ata_piix?

I have enabled the ATA drivers on my test system now, and I still don't
see the issue. "hd*" for CDROM devices has been marked deprecated in
udev since 2009 (!).

Is it possible that you have the legacy udisksd running, and didn't
disable CD-ROM polling?

Martin