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From: Paul Mackerras <paulus@ozlabs.org>
To: kvm@vger.kernel.org
Cc: kvm-ppc@vger.kernel.org, "Cédric Le Goater" <clg@kaod.org>
Subject: [PATCH 0/4] KVM: PPC: Book3S: Fix potential deadlocks
Date: Thu, 23 May 2019 16:34:24 +1000	[thread overview]
Message-ID: <20190523063424.GB19655@blackberry> (raw)

Recent reports of lockdep splats in the HV KVM code revealed that it
was taking the kvm->lock mutex in several contexts where a vcpu mutex
was already held.  Lockdep has only started warning since I added code
to take the vcpu mutexes in the XIVE device release functions, but
since Documentation/virtual/kvm/locking.txt specifies that the vcpu
mutexes nest inside kvm->lock, it seems that the new code is correct
and it is most of the old uses of kvm->lock that are wrong.

This series should fix the problems, by adding new mutexes that nest
inside the vcpu mutexes and using them instead of kvm->lock.

Paul.

             reply	other threads:[~2019-05-23  6:36 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-23  6:34 Paul Mackerras [this message]
2019-05-23  6:35 ` [PATCH 1/4] KVM: PPC: Book3S HV: Avoid touching arch.mmu_ready in XIVE release functions Paul Mackerras
2019-05-23  6:35 ` [PATCH 2/4] KVM: PPC: Book3S HV: Use new mutex to synchronize MMU setup Paul Mackerras
2019-05-23  6:36 ` [PATCH 3/4] KVM: PPC: Book3S: Use new mutex to synchronize access to rtas token list Paul Mackerras
2019-05-23  7:11   ` Cédric Le Goater
2019-05-29  1:54   ` [PATCH v2 " Paul Mackerras
2019-05-23  6:36 ` [PATCH 4/4] KVM: PPC: Book3S HV: Don't take kvm->lock around kvm_for_each_vcpu Paul Mackerras
2019-05-23  7:11   ` Cédric Le Goater
2019-05-23  7:21 ` [PATCH 0/4] KVM: PPC: Book3S: Fix potential deadlocks Alexey Kardashevskiy
2019-05-23  7:41   ` Cédric Le Goater
2019-05-23  8:31   ` Paul Mackerras
2019-05-24  9:17 ` Cédric Le Goater
2019-05-28  4:54   ` Paul Mackerras
2019-05-31  6:32 ` Paul Mackerras

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