From: Ingo Molnar <mingo@kernel.org>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: Ard Biesheuvel <ardb+git@google.com>,
linux-kernel@vger.kernel.org, x86@kernel.org
Subject: Re: [RFC PATCH PoC 01/11] x86/linkage: Add SYM_PI_ALIAS() macro helper to emit symbol aliases
Date: Thu, 24 Apr 2025 20:23:19 +0200 [thread overview]
Message-ID: <aAqBl3Odf4oX2SCL@gmail.com> (raw)
In-Reply-To: <CAMj1kXG4umHx6ebVRjg-C+_xJRRBrxmqhiDKqVychCPF9PJoGQ@mail.gmail.com>
* Ard Biesheuvel <ardb@kernel.org> wrote:
> On Thu, 24 Apr 2025 at 20:05, Ingo Molnar <mingo@kernel.org> wrote:
> >
> >
> > * Ard Biesheuvel <ardb+git@google.com> wrote:
> >
> > > From: Ard Biesheuvel <ardb@kernel.org>
> > >
> > > Startup code that may execute from the early 1:1 mapping of memory will
> > > be confined into its own address space, and only be permitted to access
> > > ordinary kernel symbols if this is known to be safe.
> > >
> > > Introduce a macro helper PI_ALIAS() that emits a __pi_ prefixed alias
> > > for a symbol, which allows startup code to access it.
> >
> > s/PI_ALIAS
> > /SYM_PI_ALIAS
> >
> > What does 'PI' stand for? 'Physical memory Identity' map?
> >
>
> 'position independent'
/facepalm
Clearly it's getting late here :)
> - it's what we ended up with on arm64, but I'm
> not attached to it so happy to switch to something better.
Could we make it something like SYM_PIC_ALIAS() at least? Because 'PIC'
is something most people will recognize in this context. PI goes for
3.1415. ;-)
Thanks,
Ingo
next prev parent reply other threads:[~2025-04-24 18:23 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-04-23 11:09 [RFC PATCH PoC 00/11] x86: strict separation of startup code Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 01/11] x86/linkage: Add SYM_PI_ALIAS() macro helper to emit symbol aliases Ard Biesheuvel
2025-04-24 18:05 ` Ingo Molnar
2025-04-24 18:17 ` Ard Biesheuvel
2025-04-24 18:23 ` Ingo Molnar [this message]
2025-04-23 11:09 ` [RFC PATCH PoC 02/11] x86/boot: Move early_setup_gdt() back into head64.c Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 03/11] x86/boot: Disregard __supported_pte_mask in __startup_64() Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 04/11] x86/boot: Add a bunch of PI aliases Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 05/11] HACK: provide __pti_set_user_pgtbl() to startup code Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 06/11] x86/boot: Created a confined code area for " Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 07/11] HACK: work around sev-startup.c being omitted for now Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 08/11] x86/boot: Move startup code out of __head section Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 09/11] x86/boot: Disallow absolute symbol references in startup code Ard Biesheuvel
2025-04-23 11:09 ` [RFC PATCH PoC 10/11] x86/boot: Revert "Reject absolute references in .head.text" Ard Biesheuvel
2025-04-23 11:10 ` [RFC PATCH PoC 11/11] x86/boot: Get rid of the .head.text section Ard Biesheuvel
2025-04-24 18:09 ` [RFC PATCH PoC 00/11] x86: strict separation of startup code Ingo Molnar
2025-04-24 18:16 ` Ard Biesheuvel
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