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Date:   Mon, 29 May 2023 20:42:18 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Badhri Jagan Sridharan <badhri@google.com>
Cc:     gregkh@linuxfoundation.org, colin.i.king@gmail.com,
        xuetao09@huawei.com, quic_eserrao@quicinc.com,
        water.zhangjiantao@huawei.com, peter.chen@freescale.com,
        balbi@ti.com, francesco@dolcini.it, alistair@alistair23.me,
        stephan@gerhold.net, bagasdotme@gmail.com, luca@z3ntu.xyz,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
Subject: Re: [PATCH v4 1/3] Revert "Revert "usb: gadget: udc: core: Invoke
 usb_gadget_connect only when started""
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On Mon, May 29, 2023 at 11:48:14PM +0000, Badhri Jagan Sridharan wrote:
> This reverts commit f22e9b67f19ccc73de1ae04375d4b30684e261f8.
> 
> The regression reported in
> https://lore.kernel.org/all/ZF4bMptC3Lf2Hnee@gerhold.net/ is being
> fixed in
> commit 7d7863db7cc0 ("usb: gadget: udc: core: Offload usb_udc_vbus_handler processing").

What commit is that?  It doesn't exist yet, at least, not in the 
mainline kernel.

> Hence reverting the revert.
> 
> Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>

No!  Do not do this.  If you do, there will again be a version of the 
kernel that has the bug that caused the revert in the first place.  Even 
if it's only temporary, it could still affect people who are (for 
example) trying to run bisections.

Instead, reorder the patches.  First fix the underlying problem that 
led to the deadlocks.  Once that's in good shape then you can safely 
make this change.

Alan Stern