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Date:   Wed, 20 Oct 2021 16:33:16 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc:     Jie Deng <jie.deng@intel.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        Wolfram Sang <wsa@kernel.org>,
        "virtualization@lists.linux-foundation.org" 
        <virtualization@lists.linux-foundation.org>,
        "linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        kernel <kernel@axis.com>
Subject: Re: [PATCH 1/2] i2c: virtio: disable timeout handling
Message-ID: <20211020110316.4x7tnxonswjuuoiw@vireshk-i7>
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On 20-10-21, 12:55, Vincent Whitchurch wrote:
> If the timeout cannot be disabled, then the driver should be fixed to
> always copy buffers and hold on to them to avoid memory corruption in
> the case of timeout, as I mentioned in my commit message.  That would be
> quite a substantial change to the driver so it's not something I'm
> personally comfortable with doing, especially not this late in the -rc
> cycle, so I'd leave that to others.

Or we can avoid clearing up and freeing the buffers here until the
point where the buffers are returned by the host. Until that happens,
we can avoid taking new requests but return to the earlier caller with
timeout failure. That would avoid corruption, by freeing buffers
sooner, and not hanging of the kernel.

-- 
viresh