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Date: Mon, 29 Apr 2024 18:26:38 -0700
From: Dan Williams <dan.j.williams@intel.com>
To: Vishal Verma <vishal.l.verma@intel.com>, Dan Williams
	<dan.j.williams@intel.com>, Dave Jiang <dave.jiang@intel.com>, "Alison
 Schofield" <alison.schofield@intel.com>, Andrew Morton
	<akpm@linux-foundation.org>
CC: <linux-mm@kvack.org>, <nvdimm@lists.linux.dev>,
	<linux-cxl@vger.kernel.org>, <linux-kernel@vger.kernel.org>, Vishal Verma
	<vishal.l.verma@intel.com>
Subject: Re: [PATCH v2 4/4] dax/bus.c: Use the right locking mode (read vs
 write) in size_show
Message-ID: <663048ce71dab_14872949a@dwillia2-mobl3.amr.corp.intel.com.notmuch>
References: <20240416-vv-dax_abi_fixes-v2-0-d5f0c8ec162e@intel.com>
 <20240416-vv-dax_abi_fixes-v2-4-d5f0c8ec162e@intel.com>
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Vishal Verma wrote:
> In size_show(), the dax_dev_rwsem only needs a read lock, but was
> acquiring a write lock. Change it to down_read_interruptible() so it
> doesn't unnecessarily hold a write lock.
> 
> Cc: Dan Williams <dan.j.williams@intel.com>
> Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem")
> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
> ---
>  drivers/dax/bus.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Looks good,

Reviewed-by: Dan Williams <dan.j.williams@intel.com>