From: "Andreas Färber" <afaerber@suse.de>
To: Markus Armbruster <armbru@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Why is TYPE_CPU no-user?
Date: Tue, 15 Oct 2013 15:08:44 +0200 [thread overview]
Message-ID: <525D3E5C.1080007@suse.de> (raw)
In-Reply-To: <878uxuiux3.fsf@blackfin.pond.sub.org>
Hi Markus,
Am 15.10.2013 14:24, schrieb Markus Armbruster:
> To go beyond RFC with this series, I need to explain why TYPE_CPU
> cannot_instantiate_with_device_add_yet. Would you be so kind and help
> me out with a suitable comment?
>From what I remember this was done when I started the whole process and
most CPU subtypes did not yet use the QOM instance_init for
initialization. Most importantly x86 still is not yet self-contained,
nor is sparc. Such targets need to use cpu_init() et al. rather than
-device. (This became visible in the first s390x vCPU hotplug series.)
Most boards rely on being able to do postprocessing after they have
instantiated the CPU: wiring up IRQs, adding reset handlers, halting
non-first CPUs, ...
-device would skip that.
Another aspect is that no CPU subtype has been proven hot-pluggable with
device_add yet. For s390x we're the closest to date.
We could move the flag from the base type to the targets' base types if
you prefer. Then we can knock the bad values out one by one rather than
overriding the inherited value with an explicit positive one.
Cheers,
Andreas
>
> You can find examples in PATCH 2-7/9.
>
--
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg
next prev parent reply other threads:[~2013-10-15 13:09 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-10 14:42 [Qemu-devel] [PATCH RFC 0/9] Clean up and fix no_user armbru
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 1/9] qdev: Replace no_user by cannot_instantiate_with_device_add_yet armbru
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 2/9] sysbus: Set cannot_instantiate_with_device_add_yet armbru
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 3/9] apic: Document why cannot_instantiate_with_device_add_yet armbru
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 4/9] pci-host: Consistently set cannot_instantiate_with_device_add_yet armbru
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 5/9] ich9: Document why cannot_instantiate_with_device_add_yet armbru
2013-10-10 16:01 ` Paolo Bonzini
2013-10-10 16:03 ` Paolo Bonzini
2013-10-11 6:13 ` Markus Armbruster
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 6/9] piix3 piix4: " armbru
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 7/9] vt82c686: " armbru
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 8/9] isa: Clean up use of cannot_instantiate_with_device_add_yet armbru
2013-10-15 12:43 ` [Qemu-devel] Should the i8259 devices remain no-user? (was: [PATCH RFC 8/9] isa: Clean up use of cannot_instantiate_with_device_add_yet) Markus Armbruster
2013-10-15 12:54 ` [Qemu-devel] Should the i8259 devices remain no-user? Paolo Bonzini
2013-10-16 9:51 ` Markus Armbruster
2013-10-16 11:06 ` Paolo Bonzini
2013-10-16 16:12 ` Markus Armbruster
2013-10-16 16:21 ` BALATON Zoltan
2013-10-16 16:23 ` Paolo Bonzini
2013-10-26 20:00 ` [Qemu-devel] fix clearing i8259 IRQ lines (Was: Should the i8259 devices remain no-user?) Matthew Ogilvie
2013-10-29 16:27 ` BALATON Zoltan
2013-10-10 14:42 ` [Qemu-devel] [PATCH RFC 9/9] qdev: Do not let the user try to device_add when it cannot work armbru
2013-10-15 12:24 ` [Qemu-devel] Why is TYPE_CPU no-user? (was: [PATCH RFC 0/9] Clean up and fix no_user) Markus Armbruster
2013-10-15 12:37 ` Peter Maydell
2013-10-15 14:01 ` [Qemu-devel] Why is TYPE_CPU no-user? Markus Armbruster
2013-10-15 13:08 ` Andreas Färber [this message]
2013-10-16 9:55 ` Markus Armbruster
2013-10-15 13:21 ` [Qemu-devel] Which functions of southbridges should be no-user? (was: [PATCH RFC 0/9] Clean up and fix no_user) Markus Armbruster
2013-10-15 13:31 ` [Qemu-devel] Which functions of southbridges should be no-user? Andreas Färber
2013-10-15 14:41 ` Kevin Wolf
2013-10-15 14:53 ` Andreas Färber
2013-10-16 9:58 ` Markus Armbruster
2013-10-15 15:09 ` Anthony Liguori
2013-10-16 10:00 ` Markus Armbruster
2013-10-16 11:02 ` Andreas Färber
2013-10-17 9:47 ` Markus Armbruster
2013-10-16 17:53 ` Anthony Liguori
2013-10-17 9:49 ` Markus Armbruster
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