Re: [PATCH] sysfs: Remove page boundary align limitation on sysfs_emit and sysfs_emit_at

From: Greg Kroah-Hartman
Date: Thu Sep 09 2021 - 02:05:36 EST


On Thu, Sep 09, 2021 at 05:31:40AM +0000, Yu, Lang wrote:
> [AMD Official Use Only]
>
>
>
> >-----Original Message-----
> >From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> >Sent: Thursday, September 9, 2021 1:19 PM
> >To: Yu, Lang <Lang.Yu@xxxxxxx>
> >Cc: Joe Perches <joe@xxxxxxxxxxx>; Rafael J . Wysocki <rafael@xxxxxxxxxx>;
> >linux-kernel@xxxxxxxxxxxxxxx
> >Subject: Re: [PATCH] sysfs: Remove page boundary align limitation on sysfs_emit
> >and sysfs_emit_at
> >
> >On Wed, Sep 08, 2021 at 03:33:51PM +0000, Yu, Lang wrote:
> >> >Please feel free to add better documentation for the functions if you
> >> >feel people are getting confused, do not change the existing behavior
> >> >of the code as it rightly caught it being misused.
> >>
> >> You can find many patches named "convert sysfs scnprintf/snprintf to
> >syfs_emit/sysfs_emit_at".
> >> or "use sysfs_emit/sysfs_emit_at in show functions". They may think
> >> it's better to use syfs_emit/sysfs_emit_at given its overrun avoidance.
> >
> >Yes, and using that in sysfs functions is fine, there is nothing wrong with this
> >usage.
> >
> >> But there are still some corner cases(e.g., a non page boundary aligned buf
> >address : ).
> >
> >I need a specific example of where this has gone wrong. Please provide a
> >lore.kernel.org link as I fail to see the problem here.
> >
> >Are you sure that you are not just abusing sysfs and having more than one value
> >per file? Does this mean I need to go audit all of the gpu sysfs file entries?
> >
> Indeed, the one value per file rule was broken... Thanks.

Great, which file is that so we can fix it!

thanks,

greg k-h