Re: [PATCH v1 0/3] x86/traps: Fix DR6/DR7 inintialization

[Xin Li]

On 6/13/2025 12:18 AM, Peter Zijlstra wrote:
> On Fri, Jun 13, 2025 at 12:01:14AM -0700, Xin Li (Intel) wrote:
> > Since only BLD-induced #DB exceptions clear DR6.BLD and other debug
> > exceptions leave it unchanged, even if the first #DB is unrelated to
> > BLD, DR6.BLD is still cleared.  As a result, such a first #DB is
> > misinterpreted as a BLD #DB, and a false warning is triggerred.
> >
> >
> > Fix the bug by initializing DR6 by writing its architectural reset
> > value at boot time.
> >
> >
> > DR7 suffers from a similar issue.  We apply the same fix.
>
> Bah, this DR6 polarity is a pain in the behind for sure. Patches look
> good, except I'm really not a fan of using those 'names'. But I'll not
> object too much of others like it.

Let's see if there will be more objections :)