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Date: Wed, 26 Feb 2025 13:00:38 -0700
From: Keith Busch <kbusch@kernel.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: Keith Busch <kbusch@meta.com>, ming.lei@redhat.com,
	asml.silence@gmail.com, linux-block@vger.kernel.org,
	io-uring@vger.kernel.org, bernd@bsbernd.com,
	csander@purestorage.com, linux-nvme@lists.infradead.org
Subject: Re: [PATCHv7 6/6] io_uring: cache nodes and mapped buffers
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On Wed, Feb 26, 2025 at 12:58:21PM -0700, Jens Axboe wrote:
> On 2/26/25 12:43 PM, Jens Axboe wrote:
> > Ignore this one, that was bogus. Trying to understand a crash in here.
> 
> Just to wrap this up, it's the combining of table and cache that's the
> issue. The table can get torn down and freed while nodes are still
> alive - which is fine, but not with this change, as there's then no
> way to sanely put the cached entry.

Yes, the imu can outlive the table it came from, which means Pavel was
right to suggest I not tied the cache to the table. Thanks for pointing
this out.