Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 6 May 2020 16:46:02 +0200
From:   Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= <uwe@kleine-koenig.org>
To:     linux-kernel@vger.kernel.org
Cc:     rafael.j.wysocki@intel.com, jroedel@suse.de, tglx@linutronix.de,
        x86@kernel.org
Subject: Failure to shutdown/reboot with intel_iommu=on
Message-ID: <20200506144558.GA4019@taurus.defre.kleine-koenig.org>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha512;
        protocol="application/pgp-signature"; boundary="RnlQjJ0d97Da+TV1"
Content-Disposition: inline
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


--RnlQjJ0d97Da+TV1
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline

Hello,

On my Lenovo T460p I cannot shutdown and reboot when the iommu is
enabled. This is using linux 5.2.7 as provided by Debian, 5.6.4 has the
same problem. Suspend/resume also fails; I suspect this is the same
issue.

When requesting power off the kernel messages just end with:

	sd 0:0:0:0: [sda] Synchronizing SCSI cache
	sd 0:0:0:0: [sda] Stopping disk
	e1000e: EEE TX LPI TIMER: 00000011
	ACPI: Preparing to enter system sleep state S5
	reboot: Power down
	acpi_power_off called

(photo at https://www.kleine-koenig.org/tmp/uklsiommu.jpg in case I
mistyped something. Full dmesg and lspci -vvv at
https://www.kleine-koenig.org/tmp/uklsiommu.tar.gz with and without
iommu enabled.)

With the iommu disabled (CONFIG_INTEL_IOMMU_DEFAULT_ON unset or
intel_iommu=off on cmdline) the machine just works as expected
(including working suspend/resume).

I already talked to tglx on irc but unfortunately no new insights
resulted from that.

Any ideas how to fix or continue debugging the issue?

Best regards
Uwe

--RnlQjJ0d97Da+TV1
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAl6yzaMACgkQwfwUeK3K
7AlMdwf5Afr+w0Br3FyVlVy4pC4aUnHefouBHZNIol0+Hm5hb7VVMhoFw34+lR9E
0PHaJD3e39LaNgGDmk+E+zl1hR9Agdc1n0/DzQ5lR3W7N6Eh7b8XCNKt2lJFCq4n
GgGi7k7E8OOOZGJ+mcq+GY6olEa7XX1N1WVC7YSLONvAKbir8ZdBJfiFWBFTa7T7
bR8WPemukFFF5SPcWMnWRQiAA3GTIN4ywxu0gyZgbY2/TbLI5GxiYRnbhn+Ua6L1
uorkIbFMDfpznWC0tMlzQoqw2DmUMVLV36cf9I/jlBjkyGr4MNXa4BfsmT7iP39G
tIVJaVmeE5w5B7Wand11hT6XvsXWGQ==
=Uf1G
-----END PGP SIGNATURE-----

--RnlQjJ0d97Da+TV1--