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Date:   Wed, 24 May 2023 22:28:35 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Kautuk Consul <kconsul@linux.vnet.ibm.com>
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Subject: Re: [PATCH v7 08/14] KVM: Rename mmu_notifier_*
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On Wed, May 24, 2023 at 11:42:15AM +0530, Kautuk Consul wrote:

> My comment was based on the assumption that "all atomic operations are
> implicit memory barriers". If that assumption is true then we won't need

It is not -- also see Documentation/atomic_t.txt.

Specifically atomic_read() doesn't imply any ordering on any
architecture including the strongly ordered TSO-archs (like x86).