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Date:   Tue, 30 Aug 2022 10:48:36 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Saravana Kannan <saravanak@google.com>
Cc:     Zhen Lei <thunder.leizhen@huawei.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        patches@armlinux.org.uk, Kefeng Wang <wangkefeng.wang@huawei.com>,
        Linus Walleij <linus.walleij@linaro.org>
Subject: Re: [PATCH v2] ARM: Add sanity check for dev->periphid in
 amba_probe()
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References: <20220830065413.638-1-thunder.leizhen@huawei.com>
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On Tue, Aug 30, 2022 at 10:47:31AM +0100, Russell King (Oracle) wrote:
> How can we get to amba_probe() if amba_match() has not returned a
> positive match for an ID? Surely if that happens, the driver model
> is failed - since a probe function should not be called unless the
> driver matches the device.
> 
> This patch, and 9229/1 both feel like they're working around some
> brokenness elsewhere in the kernel.
> 
> The description in 9229/1, specifically "But not all drivers have .match

Sorry, meant 9238/1.

> hook, such as pl031, the dev->bus->probe will be called directly in
> __driver_attach()." AMBA drivers do not have a .match hook - the bus
> does, which all AMBA drivers must be a member of. If amba_match fails,
> there is no way that amba_probe() should ever be called.

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