Re: [PATCH v2 1/1] s390/vfio-ap: fix circular lockdep when setting/clearing crypto masks
From: Christian Borntraeger
Date: Wed Feb 24 2021 - 11:16:39 EST
On 23.02.21 10:48, Halil Pasic wrote:
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On 2021年2月15日 20:15:47 -0500
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Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote:
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> This patch fixes a circular locking dependency in the CI introduced by
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> commit f21916ec4826 ("s390/vfio-ap: clean up vfio_ap resources when KVM
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> pointer invalidated"). The lockdep only occurs when starting a Secure
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> Execution guest. Crypto virtualization (vfio_ap) is not yet supported for
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> SE guests; however, in order to avoid CI errors, this fix is being
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> provided.
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> The circular lockdep was introduced when the masks in the guest's APCB
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> were taken under the matrix_dev->lock. While the lock is definitely
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> needed to protect the setting/unsetting of the KVM pointer, it is not
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> necessarily critical for setting the masks, so this will not be done under
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> protection of the matrix_dev->lock.
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With the one little thing I commented on below addressed:
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Acked-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
Tony, can you comment on Halils comment or send a v3 right away?