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Message-ID: <96896eaeaac7cefed65098da268f92e96db69591.camel@redhat.com>
Subject: Re: [PATCH V2] IB/core: Add mitigation for Spectre V1
From:   Doug Ledford <dledford@redhat.com>
To:     "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
        "Luck, Tony" <tony.luck@intel.com>, Ira Weiny <ira.weiny@intel.com>
Cc:     Jason Gunthorpe <jgg@ziepe.ca>, Leon Romanovsky <leon@kernel.org>,
        Parav Pandit <parav@mellanox.com>, linux-rdma@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Wed, 31 Jul 2019 15:22:19 -0400
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On Wed, 2019-07-31 at 14:52 -0400, Doug Ledford wrote:
> On Wed, 2019-07-31 at 12:52 -0500, Gustavo A. R. Silva wrote:
> > This is insufficient. The speculation windows are large:
> >=20
> > "Speculative  execution  on  modern  CPUs  can  run  several
> > hundred  instructions  ahead." [1]
> >=20
> > [1] https://spectreattack.com/spectre.pdf
>=20
> Thanks, I'll take a look at that.  That issue aside, returning without
> wasting time on two mutexes is still better IMO, so I like my patch
> more
> than the proposed one.  Tony, would you like to resubmit?
>=20

Never mind, I took your V2 and fixed it up like I wanted.  Patch
applied, thanks.

--=20
Doug Ledford <dledford@redhat.com>
    GPG KeyID: B826A3330E572FDD
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