Re: [PATCH] scsi_debug: Fix compilation error on 32bits arch

[Geert Uytterhoeven <geert@linux-m68k.org>]

 	Hi Damien,


On Thu, 7 May 2020, Damien Le Moal wrote:
> Allowing a non-power-of-2 zone size forces the use of direct division
> operations of 64bits sector values to obtain a zone number or number of
> zones. Doing so without using do_div() leads to compilation errors on
> 32bits architecture.

As reported by noreply@ellerman.id.au for m68k-allmodconfig:

     ERROR: modpost: "__udivdi3" [drivers/scsi/scsi_debug.ko] undefined!

> Devices with a zone size that is not a power of 2 do not exist today so
> allowing their emulation is of limited interest, as the sd driver will
> not support them anyway. So to fix this compilation error, instead of
> using do_div() for sector values divisions, simply disallow zone size
> values that are not a power of 2 value, allowing to use bitshift for
> divisions in all cases.
>
> Fixes: 98e0a689868c ("scsi: scsi_debug: Add zone_size_mb module parameter")
> Fixes: f0d1cf9378bd ("scsi: scsi_debug: Add ZBC zone commands")
> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

And your patch fixes that, so

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

 						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
 							    -- Linus Torvalds