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Date:   Fri, 16 Jun 2023 23:14:50 +0100
From:   Mark Brown <broonie@kernel.org>
To:     Russ Weight <russell.h.weight@intel.com>
Cc:     Jim Wylder <jwylder@google.com>,
        "Gerlach, Matthew" <matthew.gerlach@linux.intel.com>,
        linux-kernel@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>
Subject: Re: [BUG] _regmap_raw_write() - divide-by-zero
Message-ID: <648e22d2-d455-4439-a00d-4042077a8571@sirena.org.uk>
References: <02da121f-d6f1-73de-1805-4b331ccbc547@intel.com>
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On Fri, Jun 16, 2023 at 02:58:24PM -0700, Russ Weight wrote:

> The origination of the regmap->max_raw_write value is here:
> https://github.com/torvalds/linux/blob/4973ca29552864a7a047ab8a15611a585827412f/drivers/base/regmap/regmap-spi-avmm.c#L663
> > .max_raw_write = SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT,

> SPI_AVMM_VAL_SIZE is defined as 4, and MAX_WRITE_CNT is defined as 1

This should add in some headroom for the value too.

We should also fix the max_raw_write comments since it's a bit confusing
between users and buses, though AFAICT nothing outside the core ever
checks.

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