Re: [PATCH] cxl/mem: Force array size of mem_commands[] to CXL_MEM_COMMAND_ID_MAX

From: Robert Richter
Date: Thu Mar 25 2021 - 04:13:34 EST


On 24.03.21 12:08:20, Dan Williams wrote:
> On Wed, Mar 24, 2021 at 11:43 AM Ira Weiny <ira.weiny@xxxxxxxxx> wrote:

> > Can't we use ARRAY_SIZE?
>
> An ARRAY_SIZE() check in cxl_validate_cmd_from_user() would work too,
> but it wouldn't give the compiler protection that Robert mentions for
> going the other way where mem_commands tries to add an entry that is
> out of bounds relative to CXL_CMDS.

I was considering that too. Another reason apart from above was to
treat 'holes' in the array caused by #ifdefs the same regardless its
position in the array. Thus, all should show up as being zeroed
instead of cutting those at the end from the array.

Thanks for applying,

-Robert