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Date:   Fri, 23 Mar 2018 08:28:07 +0100 (CET)
From:   Marta Rybczynska <mrybczyn@kalray.eu>
To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     Keith Busch <keith.busch@intel.com>,
        Ming Lei <ming.lei@redhat.com>, axboe@fb.com, hch@lst.de,
        sagi@grimberg.me, linux-nvme@lists.infradead.org,
        linux-kernel@vger.kernel.org, bhelgaas@google.com,
        linux-pci@vger.kernel.org,
        Pierre-Yves Kerbrat <pkerbrat@kalray.eu>,
        Srinath Mannam <srinath.mannam@broadcom.com>
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Subject: Re: [RFC PATCH] nvme: avoid race-conditions when enabling devices
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> On Wed, Mar 21, 2018 at 05:10:56PM +0100, Marta Rybczynska wrote:
>> 
>> The problem may happen also with other device doing its probe and
>> nvme running its workqueue (and we probably have seen it in practice
>> too). We were thinking about a lock in the pci generic code too,
>> that's why I've put the linux-pci@ list in copy.
> 
> Yes, this is a generic problem in the PCI core.  We've tried to fix it
> in the past but haven't figured it out yet.
> 
> See 40f11adc7cd9 ("PCI: Avoid race while enabling upstream bridges")
> and 0f50a49e3008 ("Revert "PCI: Avoid race while enabling upstream
> bridges"").
> 
> It's not trivial, but if you figure out a good way to fix this, I'd be
> thrilled.
> 

Bjorn, Srinath, are you aware of anyone working on an updated fix
for this one?

Marta