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Date: Mon, 27 Mar 2017 19:52:13 -0700
From: Omar Sandoval <osandov@osandov.com>
To: linux-block@vger.kernel.org
Cc: kernel-team@fb.com
Subject: Re: [PATCH 2/2] block: fix leak of q->rq_wb
Message-ID: <20170328025213.GA3451@vader>
References: <de751892a392533e8e26fffbf72ba7904cfda468.1490636543.git.osandov@fb.com>
 <d6f2baa4f64dce04da94a649d080acdaaf7d6b57.1490636543.git.osandov@fb.com>
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On Mon, Mar 27, 2017 at 10:43:59AM -0700, Omar Sandoval wrote:
> From: Omar Sandoval <osandov@fb.com>
> 
> CONFIG_DEBUG_TEST_DRIVER_REMOVE found a possible leak of q->rq_wb in a
> couple of cases: when a request queue is reregistered and when gendisks
> share a request_queue. This has been a problem since wbt was introduced,
> but the WARN_ON(!list_empty(&stats->callbacks)) in the blk-stat rework
> exposed it. The fix is unfortunately a hack until we fix all of the
> drivers sharing a request_queue.

FYI, I went through the remaining cases and fixed most of them up,
working on the remaining few. Maybe we can finally put this crap to
rest...