From: David Gibson <david@gibson.dropbear.id.au>
To: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: lvivier@redhat.com, qemu-devel@nongnu.org, groug@kaod.org,
qemu-ppc@nongnu.org, clg@kaod.org, philmd@redhat.com
Subject: Re: [Qemu-devel] [PATCH 7/7] spapr: Perform machine reset in a more sensible order
Date: Wed, 11 Sep 2019 17:51:42 +1000 [thread overview]
Message-ID: <20190911075142.GA13785@umbus.fritz.box> (raw)
In-Reply-To: <b727dcb2-3cdd-77f9-b772-3253e52f2133@ozlabs.ru>
[-- Attachment #1: Type: text/plain, Size: 3979 bytes --]
On Wed, Sep 11, 2019 at 05:40:58PM +1000, Alexey Kardashevskiy wrote:
>
>
> On 11/09/2019 14:04, David Gibson wrote:
> > We've made several changes in the past to the machine reset order to fix
> > specific problems. However, we've ended up with an order that doesn't make
> > a lot of logical sense. This is an attempt to rectify this.
> >
> > First we reset global CAS options, since that should depend on nothing
> > else. Then we reset the CPUs, which shouldn't depend on external devices.
> > Then the irq subsystem, then the bulk of devices (which might rely on
> > irqs). Finally we set up the entry state ready for boot, which could
> > potentially rely on a bunch of other things.
> >
> > Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
>
>
> Breaks console on P8 and asserts on rebooting a P9 guest.
Yeah, I jumped the gun on this one - I need to rethink and test more thoroughly.
>
>
>
> > ---
> > hw/ppc/spapr.c | 47 +++++++++++++++++++++++++----------------------
> > 1 file changed, 25 insertions(+), 22 deletions(-)
> >
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index 5a919a6cc1..1560a11738 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -1724,6 +1724,28 @@ static void spapr_machine_reset(MachineState *machine)
> > void *fdt;
> > int rc;
> >
> > + /*
> > + * If this reset wasn't generated by CAS, we should reset our
> > + * negotiated options and start from scratch
> > + */
> > + if (!spapr->cas_reboot) {
> > + spapr_ovec_cleanup(spapr->ov5_cas);
> > + spapr->ov5_cas = spapr_ovec_new();
> > +
> > + ppc_set_compat_all(spapr->max_compat_pvr, &error_fatal);
> > + }
> > +
> > + /*
> > + * There is no CAS under qtest. Simulate one to please the code that
> > + * depends on spapr->ov5_cas. This is especially needed to test device
> > + * unplug, so we do that before resetting the DRCs.
> > + */
> > + if (qtest_enabled()) {
> > + spapr_ovec_cleanup(spapr->ov5_cas);
> > + spapr->ov5_cas = spapr_ovec_clone(spapr->ov5);
> > + }
> > +
> > + /* Reset the CPUs */
> > spapr_caps_apply(spapr);
> >
> > first_ppc_cpu = POWERPC_CPU(first_cpu);
> > @@ -1741,34 +1763,15 @@ static void spapr_machine_reset(MachineState *machine)
> > spapr_setup_hpt_and_vrma(spapr);
> > }
> >
> > - qemu_devices_reset();
> > -
> > - /*
> > - * If this reset wasn't generated by CAS, we should reset our
> > - * negotiated options and start from scratch
> > - */
> > - if (!spapr->cas_reboot) {
> > - spapr_ovec_cleanup(spapr->ov5_cas);
> > - spapr->ov5_cas = spapr_ovec_new();
> > -
> > - ppc_set_compat_all(spapr->max_compat_pvr, &error_fatal);
> > - }
> > -
> > + /* Reset IRQ subsystem */
> > /*
> > * This is fixing some of the default configuration of the XIVE
> > * devices. To be called after the reset of the machine devices.
> > */
> > spapr_irq_reset(spapr, &error_fatal);
> >
> > - /*
> > - * There is no CAS under qtest. Simulate one to please the code that
> > - * depends on spapr->ov5_cas. This is especially needed to test device
> > - * unplug, so we do that before resetting the DRCs.
> > - */
> > - if (qtest_enabled()) {
> > - spapr_ovec_cleanup(spapr->ov5_cas);
> > - spapr->ov5_cas = spapr_ovec_clone(spapr->ov5);
> > - }
> > + /* Reset other devices */
> > + qemu_devices_reset();
> >
> > /* DRC reset may cause a device to be unplugged. This will cause troubles
> > * if this device is used by another device (eg, a running vhost backend
> >
>
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
next prev parent reply other threads:[~2019-09-11 7:55 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-11 4:04 [Qemu-devel] [PATCH 0/7] spapr: CAS and reset cleanup preliminaries David Gibson
2019-09-11 4:04 ` [Qemu-devel] [PATCH 1/7] spapr: Simplify handling of pre ISA 3.0 guest workaround handling David Gibson
2019-09-11 7:09 ` Cédric Le Goater
2019-09-11 7:26 ` Greg Kurz
2019-09-11 7:37 ` Alexey Kardashevskiy
2019-09-11 4:04 ` [Qemu-devel] [PATCH 2/7] spapr: Move handling of special NVLink numa node from reset to init David Gibson
2019-09-11 7:28 ` Cédric Le Goater
2019-09-11 7:33 ` Greg Kurz
2019-09-11 7:41 ` Alexey Kardashevskiy
2019-09-11 4:04 ` [Qemu-devel] [PATCH 3/7] spapr: Fixes a leak in CAS David Gibson
2019-09-11 7:28 ` Cédric Le Goater
2019-09-11 7:36 ` Greg Kurz
2019-09-11 4:04 ` [Qemu-devel] [PATCH 4/7] spapr: Skip leading zeroes from memory@ DT node names David Gibson
2019-09-11 8:01 ` Greg Kurz
2019-09-11 4:04 ` [Qemu-devel] [PATCH 5/7] spapr: Do not put empty properties for -kernel/-initrd/-append David Gibson
2019-09-11 8:46 ` Greg Kurz
2019-09-12 1:59 ` Alexey Kardashevskiy
2019-09-11 4:04 ` [Qemu-devel] [PATCH 6/7] spapr: Stop providing RTAS blob David Gibson
2019-09-11 9:16 ` Greg Kurz
2019-09-12 1:50 ` Alexey Kardashevskiy
2019-09-12 7:20 ` Greg Kurz
2019-09-11 4:04 ` [Qemu-devel] [PATCH 7/7] spapr: Perform machine reset in a more sensible order David Gibson
2019-09-11 7:40 ` Alexey Kardashevskiy
2019-09-11 7:51 ` David Gibson [this message]
2019-09-11 7:54 ` Cédric Le Goater
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190911075142.GA13785@umbus.fritz.box \
--to=david@gibson.dropbear.id.au \
--cc=aik@ozlabs.ru \
--cc=clg@kaod.org \
--cc=groug@kaod.org \
--cc=lvivier@redhat.com \
--cc=philmd@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=qemu-ppc@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).