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From: Ming Lei <ming.lei@redhat.com>
To: Daniel Wagner <dwagner@suse.de>
Cc: Wen Xiong <wenxiong@us.ibm.com>,
	james.smart@broadcom.com, linux-kernel@vger.kernel.org,
	sagi@grimberg.me, wenxiong@linux.vnet.ibm.com
Subject: Re: [PATCH 1/1] block: System crashes when cpu hotplug + bouncing port
Date: Tue, 29 Jun 2021 17:01:16 +0800	[thread overview]
Message-ID: <YNrhXFgv/gEWbhbl@T590> (raw)
In-Reply-To: <20210629083549.unco3f7atybqypw3@beryllium.lan>

On Tue, Jun 29, 2021 at 10:35:49AM +0200, Daniel Wagner wrote:
> On Tue, Jun 29, 2021 at 10:25:43AM +0200, Daniel Wagner wrote:
> > On Tue, Jun 29, 2021 at 11:47:55AM +0800, Ming Lei wrote:
> > > >    >>data.ctx = __blk_mq_get_ctx(q, cpu);
> > > >    cpu=2048 if hctx_idx = 4
> > > 
> > > Yeah, that is the issue I mentioned, any CPU in hctx->cpumask becomes
> > > offline, please try the following patch and see if it makes a
> > > difference:
> > 
> > Given that cpumask_first_and() will return nr_cpu_ids in this case,
> > can't we just bail out here and have to caller handle the error?
> 
> To answer my own question, you want to avoid adding the if into the
> hotpath.

No, this way fails the request allocation, which isn't expected from
NVMe fc/rdma/tcp/loop, since io queue can't be connected in this way.


Thanks,
Ming


  reply	other threads:[~2021-06-29  9:01 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-28  3:14 [PATCH 1/1] block: System crashes when cpu hotplug + bouncing port wenxiong
2021-06-28  9:07 ` Daniel Wagner
2021-06-28  9:59   ` Ming Lei
     [not found]     ` <71d1ce491ed5056bfa921f0e14fa646d@imap.linux.ibm.com>
2021-06-29  1:20       ` Ming Lei
     [not found]       ` <OFE573413D.44652DC5-ON00258703.000DB949-00258703.000EFCD4@ibm.com>
2021-06-29  2:56         ` Ming Lei
     [not found]         ` <OF8889275F.DC758B38-ON00258703.001297BC-00258703.00143502@ibm.com>
2021-06-29  3:47           ` Ming Lei
2021-06-29  8:25             ` Daniel Wagner
2021-06-29  8:35               ` Daniel Wagner
2021-06-29  9:01                 ` Ming Lei [this message]
2021-06-29  9:27                   ` Daniel Wagner
2021-06-29  9:35                     ` Ming Lei
2021-06-29  9:49                       ` Daniel Wagner
2021-06-29 10:06                         ` Ming Lei
2021-06-29 11:50                           ` Daniel Wagner

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