powerpc/eeh: Remove VF config space restoration

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There's a bunch of strange things about this code. First up is that none of
the fields being written to are functional for a VF. The SR-IOV
specification lists then as "Reserved, but OS should preserve" so writing
new values to them doesn't do anything and is clearly wrong from a
correctness perspective.

However, since VFs are designed to be managed by the OS there is an
argument to be made that we should be saving and restoring some parts of
config space. We already sort of do that by saving the first 64 bytes of
config space in the eeh_dev (see eeh_dev->config_space[]). This is
inadequate since it doesn't even consider saving and restoring the PCI
capability structures. However, this is a problem with EEH in general and
that needs to be fixed for non-VF devices too.

There's no real reason to keep around this around so delete it.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200725081231.39076-6-oohall@gmail.com

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This commit is contained in:

Oliver O'Halloran 2020-07-25 18:12:23 +10:00 • committed by Michael Ellerman

parent a40db93431

commit 21b43bd59c

4 changed files with 7 additions and 99 deletions

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1

arch/powerpc/include/asm/eeh.h

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59

arch/powerpc/kernel/eeh.c

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arch/powerpc/platforms/powernv/eeh-powernv.c

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arch/powerpc/platforms/pseries/eeh_pseries.c

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