On 7/1/25 17:05, Phil Dennis-Jordan wrote:
On Sat, 28 Dec 2024 at 11:48, Phil Dennis-Jordan <p...@philjordan.eu
<mailto:p...@philjordan.eu>> wrote:
On Fri, 27 Dec 2024 at 21:24, Philippe Mathieu-Daudé
<phi...@linaro.org <mailto:phi...@linaro.org>> wrote:
When the KVM accelerator is selected, the Kconfig ARM_GIC key
selects the KVM GIC implementation (ARM_GIC_KVM).
For other accelerators (TCG, HVF, ...), select the generic
implementation.
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org
<mailto:phi...@linaro.org>>
---
hw/intc/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/hw/intc/Kconfig b/hw/intc/Kconfig
index 7547528f2c2..762139d8df3 100644
--- a/hw/intc/Kconfig
+++ b/hw/intc/Kconfig
@@ -23,7 +23,7 @@ config APIC
config ARM_GIC
bool
- select ARM_GICV3 if TCG
+ select ARM_GICV3 if !KVM
Wouldn't this disable the ARM_GICV3 by default when building with --
enable-tcg --enable-kvm? And then there would be no GIC available
when running the built QEMU in TCG mode. (Bear with me, I'm a
relative Meson newbie.)
OK, I've managed to answer my own question now by setting up a RPi5 with
aarch64 RPOS and building QEMU on that with --enable-kvm --enable-tcg.
With patch 1/2 applied on current upstream master, I get:
$ build/qemu-system-aarch64 -accel tcg -M virt,gic-version=3 -smp 4 -m 4G
/[runs successfully]/
with 2/2 applied as well:
$ build/qemu-system-aarch64 -accel tcg -M virt,gic-version=3 -smp 4 -m 4G
qemu-system-aarch64: tcg does not support GICv3 emulation
$
In other words, with the proposed change, ARM_GICV3 is indeed deselected
if KVM is selected even if TCG is also selected.
Possibly very basic question: is there any support for kernel-
irqchip=off on aarch64/KVM?
If yes, don't we need ARM_GICV3 in that case anyway, so we should drop
any accel dependency on it in the first place?
Cc'ing Alex & Gustavo who are more familiar with GIC devices.
If we definitely don't need the software GIC in KVM-only builds, I guess
we're down to listing each accel that needs it individually. Is that:
select ARM_GICV3 if TCG || HVF || NVMM || WHPX || XEN_EMU || XEN
or can we drop any of those? Have I missed anything? What about QTest?
