Re: [V9fs-developer] [RFC] we should solve create-unlink-getattr idiom

From: Greg Kurz
Date: Fri Feb 09 2018 - 06:41:23 EST


On Fri, 9 Feb 2018 15:10:46 +0800
jiangyiwen <jiangyiwen@xxxxxxxxxx> wrote:

> Hi Eric and Greg,
>
> I encountered the similar problem with create-unlink-getattr idiom.
> I use the testcase that create-unlink-setattr idiom, and I see the
> bug is reported at https://bugs.launchpad.net/qemu/+bug/1336794.
> Then I also see you already fix the issue and push the patch to upstream.
> https://github.com/ericvh/linux/commit/eaf70223eac094291169f5a6de580351890162a2
> http://patchwork.ozlabs.org/patch/626194/
>
> Unfortunately, the two patches are not merged into master, I don't know
> the reason, so I suggest if the patche can be merged into master, and
> it will solve the create-unlink-getattr idiom.
>

I had tried to go a bit further and address the general issue of f*() syscalls
versus unlinked files:

QEMU:
http://lists.gnu.org/archive/html/qemu-devel/2016-06/msg07586.html

Linux 9p driver:
https://sourceforge.net/p/v9fs/mailman/message/35175775/

I remember that some issues were then reported during review of the
linux patches, and I never got bandwidth to investigate further...

But if you'd like to resurrect these threads, please do. :)

> Thanks,
> Yiwen
>

Cheers,

--
Greg