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Date: Sun, 18 Jun 2017 15:43:36 +0200
From: Christoph Hellwig <hch@lst.de>
To: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: odd sysfs find behavior, was: Re: [PATCH v6 00/10] Implement
        NVMe Namespace Descriptor Identification
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On Sun, Jun 18, 2017 at 06:20:20AM -0400, Tejun Heo wrote:
> If you "cd /sys/kernel/debug/tracing; cd -" before doing the find,
> does it succeed the first time?  It could be that the on-demand
> mounting of tracefs is giving incoherent results across the mounting
> and confusing find.

Yes, that works fine:

root@testvm:~# cd /sys/kernel/debug/tracing; cd -
/root
root@testvm:~# find /sys -name uuid
/sys/devices/virtual/nvme-fabrics/ctl/nvme3/nvme3n1/uuid
/sys/devices/virtual/nvme-fabrics/ctl/nvme2/nvme2n1/uuid