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Date:   Mon, 5 Sep 2022 07:20:10 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Manfred Spraul <manfred@colorfullife.com>
Cc:     Varsha Teratipally <teratipally@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Davidlohr Bueso <dbueso@suse.de>,
        Rafael Aquini <aquini@redhat.com>,
        Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: Request to cherry-pick 20401d1058f3f841f35a594ac2fc1293710e55b9
 to v5.10 and v5.4
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 <YxIS4jWE03E5pZjS@kroah.com>
 <b94f08a6-a2e2-c719-37ac-7c412fe1b519@colorfullife.com>
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On Sun, Sep 04, 2022 at 07:38:30PM +0200, Manfred Spraul wrote:
> Hi,
> 
> On 9/2/22 16:27, Greg Kroah-Hartman wrote:
> > On Fri, Sep 02, 2022 at 01:59:11PM +0000, Varsha Teratipally wrote:
> > > Hi all,
> > > 
> > > Commit 20401d1058f3f841f35a594ac2fc1293710e55b9("ipc: replace costly
> > > bailout check in sysvipc_find_ipc()" fixes a high cve and optimizes the
> > > costly loop by adding a checkpoint, which I think might be a good
> > > candidate for the stable branches
> > What do you mean by "high cve"?
> > 
> > And that feels like it's an artificial benchmark fixup, what real
> > workload benefits from this change?
> 
> Standard ipcs end up parsing /proc/sysvipc/*, thus there are real users
> where the performance of /proc/sysvsem/* matters.

What real users are that?  What workload needs that becides monitoring
tools?

> 
> But:
> 
> The performance of the function was bad since 2007, i.e. why is is now
> urgent? I do not see a bug that must be fixed.


Me either.

thanks,

greg k-h