linux-kernel - lsl / lsr possible confusion in v7_flush_dcache

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Date:   Thu, 8 Sep 2016 11:15:20 +0200
From:   Vincent Siles <vincent.siles@...venrun.com>
To:     Russell King <linux@...linux.org.uk>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: lsl / lsr possible confusion in v7_flush_dcache_all

Hi !
While reading the v7_flush_dcache_all (arch/arm/mm/cache-v7.S), I
stumbled upon this line:

# r10 is the current cache level
127: add    r2, r10, r10, lsr #1	    @ work out 3x current cache level

If we want r2 to be 3 * r10, we should compute r10 + (r10 << 1), which
is lsl, not lsr.

I check for a recent kernel, the issue seems to still be here:
repo:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
revision:   d71f058617564750261b673ea9b3352382b9cde4

Best regards,
Vincent Siles

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