Commit Graph

6 Commits

Author SHA1 Message Date
zhaolichang 76ca4b58c2 docs/: fix some comment spelling errors
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the docs folder.

Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200917075029.313-4-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-09-17 20:37:13 +02:00
Greg Kurz c55bcb1f47 spapr: Clarify error and documentation for broken KVM XICS
When starting an L2 KVM guest with `ic-mode=dual,kernel-irqchip=on`,
QEMU fails with:

KVM is too old to support ic-mode=dual,kernel-irqchip=on

This error message was introduced to detect older KVM versions that
didn't allow destruction and re-creation of the XICS KVM device that
we do at reboot. But it is actually the same issue that we get with
nested guests : when running under pseries, KVM currently provides
a genuine XICS device (not the XICS-on-XIVE device that we get
under powernv) which doesn't support destruction/re-creation.

This will eventually be fixed in KVM but in the meantime, update
the error message and documentation to mention the nested case.
While here, mention that in "No XIVE support in KVM" section that
this can also happen with "guest OSes supporting XIVE" since
we check this at init time before starting the guest.

Reported-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1890290
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <159664243614.622889.18307368735989783528.stgit@bahia.lan>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-08-12 13:16:27 +10:00
Cédric Le Goater 8d14523b1c docs: Update POWER9 XIVE support for nested guests
It is not yet supported.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20200804131639.407049-1-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-08-12 13:16:27 +10:00
Greg Kurz 7abc0c6d35 xics/spapr: Detect old KVM XICS on POWER9 hosts
Older KVMs on POWER9 don't support destroying/recreating a KVM XICS
device, which is required by 'dual' interrupt controller mode. This
causes QEMU to emit a warning when the guest is rebooted and to fall
back on XICS emulation:

qemu-system-ppc64: warning: kernel_irqchip allowed but unavailable:
 Error on KVM_CREATE_DEVICE for XICS: File exists

If kernel irqchip is required, QEMU will thus exit when the guest is
first rebooted. Failing QEMU this late may be a painful experience
for the user.

Detect that and exit at machine init instead.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <156044430517.125694.6207865998817342638.stgit@bahia.lab.toulouse-stg.fr.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-07-02 09:43:58 +10:00
Cédric Le Goater b87a0100cd docs: updates on the POWER9 XIVE interrupt controller documentation
This includes various small updates and a better description of the
chosen interrupt mode resulting from the combination of the 'ic-mode'
machine option, the 'kernel_irqchip' option, guest support and KVM
support.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190612160425.27670-1-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-07-02 09:43:58 +10:00
Cédric Le Goater 24563a587f docs: provide documentation on the POWER9 XIVE interrupt controller
This documents the overall XIVE architecture and the XIVE support for
sPAPR guest machines (pseries).

It also provides documentation on the 'info pic' command.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190521082411.24719-1-clg@kaod.org>
Reviewed-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-05-29 11:39:47 +10:00