Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell"
authorGuilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Mon, 11 Apr 2016 19:17:22 +0000 (16:17 -0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 8 Jun 2016 01:14:35 +0000 (18:14 -0700)
commitaf64f74e5f72903de2ce891bde1386a6d3be712c
tree94794ab7f8a688323721ddb683e3b6d3bf1e9f88
parentd140d14201f8a0e5a0d3b690ebb346f380e60386
Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell"

commit c2078d9ef600bdbe568c89e5ddc2c6f15b7982c8 upstream.

This reverts commit 89a51df5ab1d38b257300b8ac940bbac3bb0eb9b.

The function eeh_add_device_early() is used to perform EEH
initialization in devices added later on the system, like in
hotplug/DLPAR scenarios. Since the commit 89a51df5ab1d ("powerpc/eeh:
Fix crash in eeh_add_device_early() on Cell") a new check was introduced
in this function - Cell has no EEH capabilities which led to kernel oops
if hotplug was performed, so checking for eeh_enabled() was introduced
to avoid the issue.

However, in architectures that EEH is present like pSeries or PowerNV,
we might reach a case in which no PCI devices are present on boot time
and so EEH is not initialized. Then, if a device is added via DLPAR for
example, eeh_add_device_early() fails because eeh_enabled() is false,
and EEH end up not being enabled at all.

This reverts the aforementioned patch since a new verification was
introduced by the commit d91dafc02f42 ("powerpc/eeh: Delay probing EEH
device during hotplug") and so the original Cell issue does not happen
anymore.

Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/powerpc/kernel/eeh.c