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Date:   Wed, 12 Jul 2023 15:19:25 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Ming Lei <ming.lei@redhat.com>
Cc:     Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
        linux-nvme@lists.infradead.org,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        linux-scsi@vger.kernel.org, linux-block@vger.kernel.org,
        Wen Xiong <wenxiong@linux.ibm.com>,
        Keith Busch <kbusch@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/8] blk-mq: add blk_mq_max_nr_hw_queues()
Message-ID: <20230712131925.GA14596@lst.de>
References: <20230712125455.1986455-1-ming.lei@redhat.com> <20230712125455.1986455-2-ming.lei@redhat.com> <20230712130017.GA12417@lst.de> <ZK6nm2koR+TfeMcs@ovpn-8-25.pek2.redhat.com>
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On Wed, Jul 12, 2023 at 09:16:11PM +0800, Ming Lei wrote:
> The problem is that blk_mq_alloc_tag_set() forces to set nr_hw_queues
> as 1 for kdump kernel, that is why blk_mq_max_nr_hw_queues() has to
> return 1 for kdump kernel.

Well, let's fix that first and work from there.  Same argument against
that deep magic applies there as well.

> Thomas, can we disable managed irq for kdump kernel and switch to
> non-managed irq? Then we can avoid driver's change. I'd suggest
> this way if it is possible.

Why the heck would we?