Messages in this thread | | | Subject | Re: [PATCH v2 1/1] s390/vfio-ap: fix circular lockdep when setting/clearing crypto masks | From | Tony Krowiak <> | Date | Fri, 19 Feb 2021 15:49:57 -0500 |
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On 2/19/21 8:45 AM, Cornelia Huck wrote: > On Mon, 15 Feb 2021 20:15:47 -0500 > Tony Krowiak <akrowiak@linux.ibm.com> wrote: > >> This patch fixes a circular locking dependency in the CI introduced by >> commit f21916ec4826 ("s390/vfio-ap: clean up vfio_ap resources when KVM >> pointer invalidated"). The lockdep only occurs when starting a Secure >> Execution guest. Crypto virtualization (vfio_ap) is not yet supported for >> SE guests; however, in order to avoid CI errors, this fix is being >> provided. >> >> The circular lockdep was introduced when the masks in the guest's APCB >> were taken under the matrix_dev->lock. While the lock is definitely >> needed to protect the setting/unsetting of the KVM pointer, it is not >> necessarily critical for setting the masks, so this will not be done under >> protection of the matrix_dev->lock. >> >> Fixes: f21916ec4826 ("s390/vfio-ap: clean up vfio_ap resources when KVM pointer invalidated") >> Cc: stable@vger.kernel.org >> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> >> --- >> drivers/s390/crypto/vfio_ap_ops.c | 119 +++++++++++++++++++++--------- >> 1 file changed, 84 insertions(+), 35 deletions(-) > I've been looking at the patch for a bit now and tried to follow down > the various paths; and while I think it's ok, I do not really have > enough confidence about that for a R-b. But have an > > Acked-by: Cornelia Huck <cohuck@redhat.com>
Thanks for the review.
>
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