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Date: Mon, 26 Aug 2024 13:22:13 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Wei Huang <wei.huang2@amd.com>
Cc: <linux-pci@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
 <linux-doc@vger.kernel.org>, <netdev@vger.kernel.org>,
 <Jonathan.Cameron@Huawei.com>, <helgaas@kernel.org>, <corbet@lwn.net>,
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 <somnath.kotur@broadcom.com>, <andrew.gospodarek@broadcom.com>,
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 <vadim.fedorenko@linux.dev>, <horms@kernel.org>, <bagasdotme@gmail.com>,
 <bhelgaas@google.com>, <lukas@wunner.de>, <paul.e.luse@intel.com>,
 <jing2.liu@intel.com>
Subject: Re: [PATCH V4 11/12] bnxt_en: Add TPH support in BNXT driver
Message-ID: <20240826132213.4c8039c0@kernel.org>
In-Reply-To: <20240822204120.3634-12-wei.huang2@amd.com>
References: <20240822204120.3634-1-wei.huang2@amd.com>
	<20240822204120.3634-12-wei.huang2@amd.com>
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On Thu, 22 Aug 2024 15:41:19 -0500 Wei Huang wrote:
> +		rtnl_lock();
> +		bnxt_close_nic(irq->bp, false, false);
> +		bnxt_open_nic(irq->bp, false, false);
> +		rtnl_unlock();

This code means that under memory pressure changing CPU affinity
can take the machine offline. The entire machine, even if container
orchestration is trying to just move a few IRQs in place for a new
container.

We can't let you do this, it will set a bad precedent. I can't think
of any modern driver with reconfiguration safety as bad as bnxt.
Technical debt coming due.