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Date:   Tue, 19 Sep 2023 12:19:59 +0200
From:   Wolfram Sang <wsa@kernel.org>
To:     Catalin Marinas <catalin.marinas@arm.com>
Cc:     Jan Bottorff <janb@os.amperecomputing.com>,
        Serge Semin <fancer.lancer@gmail.com>,
        Yann Sionneau <yann@sionneau.net>,
        Will Deacon <will@kernel.org>,
        Jarkko Nikula <jarkko.nikula@linux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Jan Dabros <jsd@semihalf.com>,
        Andi Shyti <andi.shyti@kernel.org>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org,
        Yann Sionneau <ysionneau@kalrayinc.com>
Subject: Re: [PATCH v2] i2c: designware: Fix corrupted memory seen in the ISR
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> I also agree that a wmb() in the i2c driver is not the more elegant fix.
> For similar reasons, we hid barriers in the write*() macros, drivers
> need to stay architecture-agnostic as much as possible.

Exactly my thinking. I wanted to read this patch discussion later this
week. But from glimpsing at it so far, I already wondered why there
isn't a memory barrier in the final accessor to the register.


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