Re: [PATCH Part1 v5 23/38] x86/head/64: set up a startup %gs for stack protector

Michael Roth
2021-08-30T15:55:51Z

On Wed, Aug 25, 2021 at 06:29:31PM +0200, Borislav Petkov wrote:
> On Wed, Aug 25, 2021 at 10:18:35AM -0500, Michael Roth wrote:
> > On Wed, Aug 25, 2021 at 04:29:13PM +0200, Borislav Petkov wrote:
> > > On Fri, Aug 20, 2021 at 10:19:18AM -0500, Brijesh Singh wrote:
> > > > From: Michael Roth <michael.roth@amd.com>
> > > >
> > > > As of commit 103a4908ad4d ("x86/head/64: Disable stack protection for
> > > > head$(BITS).o") kernel/head64.c is compiled with -fno-stack-protector
> > > > to allow a call to set_bringup_idt_handler(), which would otherwise
> > > > have stack protection enabled with CONFIG_STACKPROTECTOR_STRONG. While
> > > > sufficient for that case, this will still cause issues if we attempt to
> ^^^
>
> I'm tired of repeating the same review comments with you guys:
>
> Who's "we"?
>
> Please use passive voice in your text: no "we" or "I", etc.
> Personal pronouns are ambiguous in text, especially with so many
> parties/companies/etc developing the kernel so let's avoid them please.

That had also been fixed in the commit message fixup that got clobbered, but
I still missed it in one of the comments as well so I'll be more careful of
this.

>
> How about you pay more attention?

I've been periodically revising/rewording my comments since I saw you're
original comments to Brijesh a few versions back, but it's how I normally
talk when discussing code with people so it keeps managing to sneak back in.

I've added a git hook to check for this and found other instances that need
fixing as well, so hopefully with the help of technology I can get them all
sorted for the next spin.

>
> > I didn't realize the the 32-bit path was something you were suggesting
> > to have added in this patch, but I'll take a look at that as well.
>
> If you're going to remove the -no-stack-protector thing for that file,
> then pls remove it for both 32- and 64-bit. I.e., the revert what
> 103a4908ad4d did.

Got it, will do.

>
> --
> Regards/Gruss,
> Boris.
>
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpeople.kernel.org%2Ftglx%2Fnotes-about-netiquette&amp;data=04%7C01%7Cmichael.roth%40amd.com%7Cdfceeb76d2a4481da83f08d967e57220%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637655057436180426%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=aAKQ%2B7mXBvL4oofk0y7CacaMMD8Ucg8YL5hB4nw7zgo%3D&amp;reserved=0