Re: [PATCH v14 1/7] x86/cet/ibt: Add Kconfig option for user-mode Indirect Branch Tracking

Yu, Yu-cheng
2020-10-12T20:30:03Z

On 10/12/2020 12:15 PM, Cyrill Gorcunov wrote:
> On Mon, Oct 12, 2020 at 08:45:24AM -0700, Yu-cheng Yu wrote:
> ...
>> + the application support it. When this feature is enabled,
>> + legacy non-IBT applications continue to work, but without
>> + IBT protection.
>> + Support for this feature is only known to be present on
>> + processors released in 2020 or later. CET features are also
>> + known to increase kernel text size by 3.7 KB.
>
> It seems the last sentence is redundant - new features always bloat
> the kernel code and precise size may differ depending on compiler
> and options. Surely this can be patched on top.
>

This was added after some discussion in v12 about kernel text size [1].
I think these few extra words can help people who have older machines
and want to save some space. Yes, like you said, if later we don't want
this sentence, I will be happy to add a patch to remove it. Thanks for
the feedback.

Yu-cheng

[1]