From: Vladimir Murzin <vladimir.murzin@arm.com>
To: Marc Zyngier <marc.zyngier@arm.com>, kvmarm@lists.cs.columbia.edu
Cc: andre.przywara@arm.com, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v3 1/8] arm64: KVM: Use static keys for selecting the GIC backend
Date: Fri, 9 Sep 2016 14:45:15 +0100 [thread overview]
Message-ID: <57D2BCEB.3030306@arm.com> (raw)
In-Reply-To: <57D281F1.5000902@arm.com>
On 09/09/16 10:33, Vladimir Murzin wrote:
> Hi Marc,
>
> On 09/09/16 10:19, Marc Zyngier wrote:
>> > Hi Vladimir,
>> >
> ...
>>> >>
>>> >> +extern struct static_key_false kvm_gicv3_cpuif;
>> >
>> > I think we should follow the model set by kvm_vgic_global_state, which
>> > is declared in arm_vgic.h. Even better, we should *embed* the static key
>> > in this structure. This will reduce the clutter and we wouldn't have to
>> > deal with all the section stuff (the hyp_data thing is a good cleanup,
>> > but I'd like to see it as a separate patch if possible).
> Yes, it is what I was thinking about too, but was not sure about which
> way to go, so hyp_data seemed me something we might reuse latter.
> However, I agree that we can defer hyp_data thing...
>
I've just tried it out and it seems that static keys are not happy to
accept a key after kern_hyp_va is applied at &kvm_vgic_global_state:
> In file included from ./include/linux/jump_label.h:105:0,
> from arch/arm64/kvm/hyp/switch.c:19:
> ./arch/arm64/include/asm/jump_label.h: In function ‘__guest_run’:
> ./arch/arm64/include/asm/jump_label.h:31:2: warning: asm operand 0 probably doesn’t match constraints
> asm goto("1: nop\n\t"
> ^
> ./arch/arm64/include/asm/jump_label.h:31:2: warning: asm operand 0 probably doesn’t match constraints
> asm goto("1: nop\n\t"
> ^
> ./arch/arm64/include/asm/jump_label.h:31:2: error: impossible constraint in ‘asm’
> asm goto("1: nop\n\t"
> ^
> ./arch/arm64/include/asm/jump_label.h:31:2: error: impossible constraint in ‘asm’
> asm goto("1: nop\n\t"
> ^
> make[1]: *** [arch/arm64/kvm/hyp/switch.o] Error 1
> make: *** [arch/arm64/kvm/hyp/switch.o] Error 2
it looks like we cannot avoid hyp_data thing... if you don't mind I can
do hyp_data clean-up in separate patch. Alternatively, we can do
conversion to static keys for both architectures later as an
optimisation step.
Cheers
Vladimir
next prev parent reply other threads:[~2016-09-09 13:36 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-08 16:06 [PATCH v3 0/8] ARM: KVM: Support for vgic-v3 Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 1/8] arm64: KVM: Use static keys for selecting the GIC backend Vladimir Murzin
2016-09-09 9:19 ` Marc Zyngier
2016-09-09 9:33 ` Vladimir Murzin
2016-09-09 13:45 ` Vladimir Murzin [this message]
2016-09-09 14:17 ` Marc Zyngier
2016-09-09 15:14 ` Vladimir Murzin
2016-09-09 15:25 ` Marc Zyngier
2016-09-09 16:18 ` Vladimir Murzin
2016-09-09 17:06 ` Marc Zyngier
2016-09-08 16:06 ` [PATCH v3 2/8] arm64: KVM: Move GIC accessors to arch_gicv3.h Vladimir Murzin
2016-09-09 16:32 ` Marc Zyngier
2016-09-12 9:18 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 3/8] arm64: KVM: Move vgic-v3 save/restore to virt/kvm/arm/hyp Vladimir Murzin
2016-09-09 16:33 ` Marc Zyngier
2016-09-12 9:18 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 4/8] KVM: arm64: vgic-its: Introduce config option to guard ITS specific code Vladimir Murzin
2016-09-09 16:46 ` Marc Zyngier
2016-09-12 9:23 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 5/8] KVM: arm: vgic: Support 64-bit data manipulation on 32-bit host systems Vladimir Murzin
2016-09-09 16:55 ` Marc Zyngier
2016-09-12 9:25 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 6/8] ARM: Change MPIDR_AFFINITY_LEVEL to ignore Aff3 Vladimir Murzin
2016-09-09 16:59 ` Marc Zyngier
2016-09-12 9:39 ` Vladimir Murzin
2016-09-12 9:48 ` Marc Zyngier
2016-09-12 9:51 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 7/8] ARM: Move system register accessors to asm/cp15.h Vladimir Murzin
2016-09-09 17:05 ` Marc Zyngier
2016-09-12 9:42 ` Vladimir Murzin
2016-09-12 9:44 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 8/8] ARM: KVM: Support vgic-v3 Vladimir Murzin
2016-09-09 16:45 ` Marc Zyngier
2016-09-12 9:23 ` Vladimir Murzin
2016-09-09 7:58 ` [PATCH v3 0/8] ARM: KVM: Support for vgic-v3 Vladimir Murzin
2016-09-09 11:26 ` Christoffer Dall
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