From nobody Thu Feb 23 00:29:40 2023 X-Original-To: freebsd-arch@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4PMYnP1wMSz3sfhH for ; Thu, 23 Feb 2023 00:29:45 +0000 (UTC) (envelope-from jmg@gold.funkthat.com) Received: from gold.funkthat.com (gold.funkthat.com [IPv6:2001:470:800b::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "gate2.funkthat.com", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4PMYnN5K6zz3y5y for ; Thu, 23 Feb 2023 00:29:44 +0000 (UTC) (envelope-from jmg@gold.funkthat.com) Authentication-Results: mx1.freebsd.org; none Received: from gold.funkthat.com (localhost [127.0.0.1]) by gold.funkthat.com (8.15.2/8.15.2) with ESMTPS id 31N0Tf5Y062811 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 22 Feb 2023 16:29:41 -0800 (PST) (envelope-from jmg@gold.funkthat.com) Received: (from jmg@localhost) by gold.funkthat.com (8.15.2/8.15.2/Submit) id 31N0TeSr062809; Wed, 22 Feb 2023 16:29:40 -0800 (PST) (envelope-from jmg) Date: Wed, 22 Feb 2023 16:29:40 -0800 From: John-Mark Gurney To: Konstantin Belousov Cc: Warner Losh , freebsd-arch@freebsd.org Subject: Re: making identify_hypervisor arch independent Message-ID: <20230223002940.GS95670@funkthat.com> Mail-Followup-To: Konstantin Belousov , Warner Losh , freebsd-arch@freebsd.org References: <20230222040556.GP95670@funkthat.com> List-Id: Discussion related to FreeBSD architecture List-Archive: https://lists.freebsd.org/archives/freebsd-arch List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-arch@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Operating-System: FreeBSD 11.3-STABLE amd64 X-PGP-Fingerprint: D87A 235F FB71 1F3F 55B7 ED9B D5FF 5A51 C0AC 3D65 X-Files: The truth is out there X-URL: https://www.funkthat.com/ X-Resume: https://www.funkthat.com/~jmg/resume.html X-TipJar: bitcoin:13Qmb6AeTgQecazTWph4XasEsP7nGRbAPE X-to-the-FBI-CIA-and-NSA: HI! HOW YA DOIN? can i haz chizburger? User-Agent: Mutt/1.6.1 (2016-04-27) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.4.3 (gold.funkthat.com [127.0.0.1]); Wed, 22 Feb 2023 16:29:41 -0800 (PST) X-Rspamd-Queue-Id: 4PMYnN5K6zz3y5y X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-ThisMailContainsUnwantedMimeParts: N Konstantin Belousov wrote this message on Wed, Feb 22, 2023 at 12:44 +0200: > On Tue, Feb 21, 2023 at 10:22:41PM -0700, Warner Losh wrote: > > On Tue, Feb 21, 2023 at 9:06 PM John-Mark Gurney wrote: > > > > > Hello, > > > > > > I have a pending diff (https://reviews.freebsd.org/D38721) that will make > > > SMBIOS work on arm64 systems (specifically under qemu, but likely it may > > > add support for other EFI arm64 systems that have SMBIOS as well). > > > > > > The goal is to support identifying that we are running as a guest under > > > QEMU so that we automatically switch to hz=100 on arm64. > > > > > > Currently there is code in x86/x86/identcpu.c that has code to identify > > > hypervisers via SMBIOS, so I'd like to move most of identify_hypervisor > > > to a new location so that arm64 code can call it as well. > > > > > > Where should I put it? kern/subr_identsmbios.c? And make it optional > > > on EFIRT for arm64 and standard on x86? > > > > I'd do kern/subr_smbios.c. > > > > I'd be tempted to make it standard, since EFI is basically required for > > arm64. It's not dependent at all on efi run time support. > Why not extend existing sys/dev/smbios? Because it's not a device like dev says it should be. > We do not put hardware-specific stuff in generic kernel sources' directory. Then where do/should we put cross platform (in this case, at least amd64 and arm64), non-device files? The code needs to be called before devices are probed. > > > I briefly thought of dev/smbios, BUT, that brings up another issue, > > > I think we should deorbit dev/smbios, and move smbios.h to dev/ipmi, > > > because as far as I can tell, the device does nothing useful. It > > > allocates the resource, but nothing that I can find in the tree attempts > > > to use/access the device, and it doesn't expose any interface. The > > > header is only used by dev/ipmi for the structure, but not the device, > > > as ipmi does it's own parsing of the table. > > > > > > All of the uses of smbios data is getting it via kenv which is populated > > > via loader (libsa). > > > > > > > I'd be tempted to move all the smbios walking into subr_smbios.c. > > > > All the other smbios stuff does depend on the boot loader walking > > and parsing the table and setting that in the kenv... I'd almost be tempted > > to make those into wrappers to make it harder to misspell the string they > > all pass in... Even if it's just a wrapper around kenv_getenv with the > > right string... They are mostly used for 'quirks'. > > > > Either way, I think sys/dev/smbios likely has limited value... It would be > > different if it provided some way to get the raw smbios table... But as > > it is, I think all programs that parse it get it via /dev/mem... -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."