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Subject: Re: [PATCH v4] tty: serial: jsm: allocate queue buffer at probe time
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Zheyu Ma <zheyuma97@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "open list:SERIAL DRIVERS" <linux-serial@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <1625489588-26079-1-git-send-email-zheyuma97@gmail.com>
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From:   Jiri Slaby <jirislaby@kernel.org>
Message-ID: <ffa624c5-fc2a-780a-17d2-404cd94a289a@kernel.org>
Date:   Wed, 7 Jul 2021 21:13:13 +0200
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On 07. 07. 21, 14:52, Andy Shevchenko wrote:
> On Wed, Jul 7, 2021 at 10:50 AM Jiri Slaby <jirislaby@kernel.org> wrote:
>> On 05. 07. 21, 14:53, Zheyu Ma wrote:
> 
>> So how it comes an interrupt came before
>> neo_param() in jsm_tty_open was called?
> 
> If IRQ is shared we have a special debug feature to test shared IRQs
> on freeing IRQ stage (*).
> But it doesn't matter, the IRQ handler must survive at any stage after
> the action has been listed.

Yes, but IRQ_NONE is returned from the ISR in that case.

The issue the patch is fixing is for a "malicious" device and I am not 
sure we want to fix this -- if I can put in a malicious device, I can 
use hammer to kill the box too…

thanks,
-- 
js