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Date:   Mon, 20 Jan 2020 09:51:44 -0800
From:   Davidlohr Bueso <dave@stgolabs.net>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Davidlohr Bueso <dbueso@suse.de>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        linux-m68k <linux-m68k@lists.linux-m68k.org>
Subject: Re: [PATCH] lib/rbtree: avoid pointless rb_node alignment
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References: <20200110215429.30360-1-dave@stgolabs.net>
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On Mon, 20 Jan 2020, Geert Uytterhoeven wrote:

>timerqueue_del() uses rbtree, and
>
>    #define rb_parent(r)   ((struct rb_node *)((r)->__rb_parent_color & ~3))
>
>relies on all objects being 4-byte aligned.  But your patch broke that
>assumption on m68k, where the default alignment is 2-byte.
>
>Andrew: please drop this patch.

Yeah that's too bad. I'll send a patch improving the comment around the alignment
once the patch is dropped.

Thanks,
Davidlohr