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Date:   Mon, 7 Jun 2021 15:01:44 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     "Enrico Weigelt, metux IT consult" <lkml@metux.net>
Cc:     Jason Wang <jasowang@redhat.com>,
        "Tian, Kevin" <kevin.tian@intel.com>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        Liu Yi L <yi.l.liu@linux.intel.com>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "Alex Williamson (alex.williamson@redhat.com)\"\"" 
        <alex.williamson@redhat.com>, David Woodhouse <dwmw2@infradead.org>
Subject: Re: [RFC] /dev/ioasid uAPI proposal
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On Mon, Jun 07, 2021 at 03:30:21PM +0200, Enrico Weigelt, metux IT consult wrote:
> On 02.06.21 19:21, Jason Gunthorpe wrote:
> 
> Hi,
> 
> > Not really, once one thing in an applicate uses a large number FDs the
> > entire application is effected. If any open() can return 'very big
> > number' then nothing in the process is allowed to ever use select.
> 
> isn't that a bug in select() ?

<shrug> it is what it is, select has a fixed size bitmap of FD #s and
a hard upper bound on that size as part of the glibc ABI - can't be
fixed.

Jason