vfio/spapr_tce: Get rid of possible infinite loop
authorAlexey Kardashevskiy <aik@ozlabs.ru>
Tue, 2 Oct 2018 03:22:31 +0000 (13:22 +1000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 5 Dec 2019 14:37:42 +0000 (15:37 +0100)
commit7a0d07f81e7e38ad063f9f94edcb812dff868a4f
tree99c7a5130da45917b5b0f3cc5450ba6bb3309bb0
parent4fc4b8531e870c28d2da90b5ced666456e4cfa38
vfio/spapr_tce: Get rid of possible infinite loop

[ Upstream commit 517ad4ae8aa93dccdb9a88c27257ecb421c9e848 ]

As a part of cleanup, the SPAPR TCE IOMMU subdriver releases preregistered
memory. If there is a bug in memory release, the loop in
tce_iommu_release() becomes infinite; this actually happened to me.

This makes the loop finite and prints a warning on every failure to make
the code more bug prone.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/vfio/vfio_iommu_spapr_tce.c