From: "Kani, Toshimitsu" <toshi.kani@hpe.com>
To: "dan.j.williams@intel.com" <dan.j.williams@intel.com>,
        "linux-nvdimm@lists.01.org" <linux-nvdimm@lists.01.org>
CC: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] libnvdimm, region, pmem: fix 'badblocks'
 sysfs_get_dirent() reference lifetime
Thread-Topic: [PATCH] libnvdimm, region, pmem: fix 'badblocks'
 sysfs_get_dirent() reference lifetime
Thread-Index: AQHS8oK+ynsu+mKl7UesmJueC2+/0qJA7CwA
Date: Sun, 2 Jul 2017 19:31:49 +0000
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On Sat, 2017-07-01 at 08:50 -0700, Dan Williams wrote:
> We need to hold a reference on the 'dirent' until we are sure there
> are no more notifications that will be sent. As noted in the new
> comments we take advantage of the fact that the references are taken
> and dropped under device_lock() and that nd_device_notify() holds
> device_lock() over new badblocks notifications. The notifications
> that happen when badblocks are cleared only occur while the device is
> active.
> 
> Also take the opportunity to fix up the error messages to report the
> user visible effect of a sysfs_get_dirent() failure.
> 
> Fixes: 975750a98c26 ("libnvdimm, pmem: Add sysfs notifications to
> badblocks")
> Cc: Toshi Kani <toshi.kani@hpe.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Reviewed-by: Toshi Kani <toshi.kani@hpe.com>

Thanks Dan!
-Toshi