From: Rusty Russell <rusty.russell@linaro.org>
To: Christoffer Dall <c.dall@virtualopensystems.com>,
android-virt@lists.cs.columbia.edu, kvm@vger.kernel.org,
"Peter Maydell" <peter.maydell@linaro.org>
Cc: tech@virtualopensystems.com
Subject: Re: [PATCH v7 08/12] ARM: KVM: World-switch implementation
Date: Fri, 23 Mar 2012 10:53:40 +1030 [thread overview]
Message-ID: <87wr6c88s3.fsf@rustcorp.com.au> (raw)
In-Reply-To: <20120312065241.8074.44277.stgit@ubuntu>
On Mon, 12 Mar 2012 02:52:41 -0400, Christoffer Dall <c.dall@virtualopensystems.com> wrote:
> @@ -236,6 +237,24 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
>
> int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
> {
> + unsigned long cpsr;
> + unsigned long sctlr;
> +
> +
> + /* Init execution CPSR */
> + asm volatile ("mrs %[cpsr], cpsr" :
> + [cpsr] "=r" (cpsr));
> + vcpu->arch.regs.cpsr = SVC_MODE | PSR_I_BIT | PSR_F_BIT | PSR_A_BIT |
> + (cpsr & PSR_E_BIT);
> +
> + /* Init SCTLR with MMU disabled */
> + asm volatile ("mrc p15, 0, %[sctlr], c1, c0, 0" :
> + [sctlr] "=r" (sctlr));
> + vcpu->arch.cp15[c1_SCTLR] = sctlr & ~1U;
> +
> + /* Compute guest MPIDR */
> + vcpu->arch.cp15[c0_MPIDR] = (read_cpuid_mpidr() & ~0xff)
> + | vcpu->vcpu_id;
> return 0;
> }
Hi Christoffer!
I started cleaning this up, on the theory that we should use the
defined reset values rather than basing them on host values. Then I
discovered that this is ignored by qemu anyway, which overrides the
values (except for MPIDR: I set that to 0x80000000 | vcpu->vcpu_id,
which seems correct to me).
Should this code be dropped altogether? Peter points out that once we
add new regs, they *must* be initialized to correct reset values in case
older QEMU knows nothing about them, but for the rest it just seems
confusing...
Thanks,
Rusty.
--
How could I marry someone with more hair than me? http://baldalex.org
next prev parent reply other threads:[~2012-03-23 0:35 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-12 6:51 [PATCH v7 00/12] KVM/ARM Implementation Christoffer Dall
2012-03-12 6:51 ` [PATCH v7 01/12] KVM: Introduce __KVM_HAVE_IRQ_LINE Christoffer Dall
2012-03-23 0:41 ` [PATCH] ARM: KVM: Check the cpuid we're being asked to emulate Rusty Russell
2012-05-14 22:57 ` Christoffer Dall
2012-05-16 23:58 ` Rusty Russell
2012-05-20 18:34 ` Christoffer Dall
2012-05-21 1:13 ` Rusty Russell
2012-03-12 6:52 ` [PATCH v7 02/12] KVM: Guard mmu_notifier specific code with CONFIG_MMU_NOTIFIER Christoffer Dall
2012-03-12 15:50 ` Avi Kivity
2012-03-12 6:52 ` [PATCH v7 03/12] ARM: KVM: Initial skeleton to compile KVM support Christoffer Dall
2012-03-12 6:52 ` [PATCH v7 04/12] ARM: KVM: Hypervisor identity mapping Christoffer Dall
2012-03-12 6:52 ` [PATCH v7 05/12] ARM: KVM: Hypervisor inititalization Christoffer Dall
2012-03-12 6:52 ` [PATCH v7 06/12] ARM: KVM: Memory virtualization setup Christoffer Dall
2012-03-12 6:52 ` [PATCH v7 07/12] ARM: KVM: Inject IRQs and FIQs from userspace Christoffer Dall
2012-03-12 6:52 ` [PATCH v7 08/12] ARM: KVM: World-switch implementation Christoffer Dall
2012-03-23 0:23 ` Rusty Russell [this message]
2012-03-28 13:05 ` Avi Kivity
2012-03-28 21:57 ` Rusty Russell
2012-03-29 10:49 ` Avi Kivity
2012-05-14 18:08 ` Christoffer Dall
2012-03-12 6:52 ` [PATCH v7 09/12] ARM: KVM: Emulation framework and CP15 emulation Christoffer Dall
2012-03-12 6:52 ` [PATCH v7 10/12] ARM: KVM: Handle guest faults in KVM Christoffer Dall
2012-03-12 15:31 ` [Android-virt] " Marc Zyngier
2012-03-12 16:23 ` Christoffer Dall
2012-03-12 16:28 ` Marc Zyngier
2012-03-12 6:53 ` [PATCH v7 11/12] ARM: KVM: Handle I/O aborts Christoffer Dall
2012-03-12 6:53 ` [PATCH v7 12/12] ARM: KVM: Guest wait-for-interrupts (WFI) support Christoffer Dall
2012-03-12 17:36 ` [PATCH v7 00/12] KVM/ARM Implementation Avi Kivity
2012-03-23 0:40 ` [PATCH] ARM: KVM: Remove l2ctlr write Rusty Russell
2012-05-14 22:59 ` Christoffer Dall
2012-03-29 5:11 ` [PATCH 0/3] Emulation cleanups Rusty, Russell <rusty.russell
2012-03-29 5:15 ` [PATCH 1/3] ARM: KVM: Remove l2ctlr write Rusty Russell
2012-03-29 5:17 ` [PATCH 2/3] ARM: KVM: Fake up performance counters a little more precisely Rusty Russell
2012-05-14 22:49 ` Christoffer Dall
2012-05-17 0:12 ` Rusty Russell
2012-03-29 5:17 ` [PATCH 3/3] ARM: KVM: Check the cpuid we're being asked to emulate Rusty Russell
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