Re: [PATCH] kvm/ppc/booke64: Hard disable interrupts when entering the guest
On Fri, 2013-05-03 at 18:45 -0500, Scott Wood wrote: kvmppc_lazy_ee_enable() was causing interrupts to be soft-enabled (albeit hard-disabled) in kvmppc_restart_interrupt(). This led to warnings, and possibly breakage if the interrupt state was later saved and then restored (leading to interrupts being hard-and-soft enabled when they should be at least soft-disabled). Simply removing kvmppc_lazy_ee_enable() leaves interrupts only soft-disabled when we enter the guest, but they will be hard-disabled when we exit the guest -- without PACA_IRQ_HARD_DIS ever being set, so the local_irq_enable() fails to hard-enable. While we could just set PACA_IRQ_HARD_DIS after an exit to compensate, instead hard-disable interrupts before entering the guest. This way, we won't have to worry about interactions if we take an interrupt during the guest entry code. While I don't see any obvious interactions, it could change in the future (e.g. it would be bad if the non-hv code were used on 64-bit or if 32-bit guest lazy interrupt disabling, since the non-hv code changes IVPR among other things). Shouldn't the interrupts be marked soft-enabled (even if hard disabled) when entering the guest ? Ie. The last stage of entry will hard enable, so they should be soft-enabled too... if not, latency trackers will consider the whole guest periods as interrupt disabled... Now, kvmppc_lazy_ee_enable() seems to be clearly bogus to me. It will unconditionally set soft_enabled and clear irq_happened from a soft-disabled state, thus potentially losing a pending event. Book3S HV seems to be keeping interrupts fully enabled all the way until the asm hard disables, which would be fine except that I'm worried we are racy vs. need_resched signals. One thing you may be able to do is call prep_irq_for_idle(). This will tell you if something happened, giving you a chance to abort/re-enable before you go the guest. Ben. -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[v1][KVM][PATCH 1/1] kvm:ppc: enable doorbell exception with E500MC
Actually E500MC also support doorbell exception, and CONFIG_PPC_E500MC can cover BOOK3E/BOOK3E_64 as well. Signed-off-by: Tiejun Chen tiejun.c...@windriver.com --- arch/powerpc/kvm/booke.c |2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 1020119..dc1f590 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -795,7 +795,7 @@ static void kvmppc_restart_interrupt(struct kvm_vcpu *vcpu, kvmppc_fill_pt_regs(regs); timer_interrupt(regs); break; -#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_BOOK3E_64) +#if defined(CONFIG_PPC_E500MC) case BOOKE_INTERRUPT_DOORBELL: kvmppc_fill_pt_regs(regs); doorbell_exception(regs); -- 1.7.9.5 -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[RFC][KVM][PATCH 1/1] kvm:ppc:booke-64: soft-disable interrupts
For the external interrupt, the decrementer exception and the doorbell excpetion, we also need to soft-disable interrupts while doing as host interrupt handlers since the DO_KVM hook is always performed to skip EXCEPTION_COMMON then miss this original chance with the 'ints' (INTS_DISABLE). Signed-off-by: Tiejun Chen tiejun.c...@windriver.com --- arch/powerpc/kvm/bookehv_interrupts.S |9 + 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S index e8ed7d6..2fd62bf 100644 --- a/arch/powerpc/kvm/bookehv_interrupts.S +++ b/arch/powerpc/kvm/bookehv_interrupts.S @@ -33,6 +33,8 @@ #ifdef CONFIG_64BIT #include asm/exception-64e.h +#include asm/hw_irq.h +#include asm/irqflags.h #else #include ../kernel/head_booke.h /* for THREAD_NORMSAVE() */ #endif @@ -469,6 +471,13 @@ _GLOBAL(kvmppc_resume_host) PPC_LL r3, HOST_RUN(r1) mr r5, r14 /* intno */ mr r14, r4 /* Save vcpu pointer. */ +#ifdef CONFIG_64BIT + /* Should we soft-disable interrupts? */ + andi. r6, r5, BOOKE_INTERRUPT_EXTERNAL | BOOKE_INTERRUPT_DECREMENTER | BOOKE_INTERRUPT_DOORBELL + beq skip_soft_dis + SOFT_DISABLE_INTS(r7,r8) +skip_soft_dis: +#endif bl kvmppc_handle_exit /* Restore vcpu pointer and the nonvolatiles we used. */ -- 1.7.9.5 -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC][KVM][PATCH 1/1] kvm:ppc:booke-64: soft-disable interrupts
On 05/06/2013 11:10 AM, Tiejun Chen wrote: For the external interrupt, the decrementer exception and the doorbell excpetion, we also need to soft-disable interrupts while doing as host interrupt handlers since the DO_KVM hook is always performed to skip EXCEPTION_COMMON then miss this original chance with the 'ints' (INTS_DISABLE). Sorry, miss to send Ben. Tiejun Signed-off-by: Tiejun Chen tiejun.c...@windriver.com --- arch/powerpc/kvm/bookehv_interrupts.S |9 + 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S index e8ed7d6..2fd62bf 100644 --- a/arch/powerpc/kvm/bookehv_interrupts.S +++ b/arch/powerpc/kvm/bookehv_interrupts.S @@ -33,6 +33,8 @@ #ifdef CONFIG_64BIT #include asm/exception-64e.h +#include asm/hw_irq.h +#include asm/irqflags.h #else #include ../kernel/head_booke.h /* for THREAD_NORMSAVE() */ #endif @@ -469,6 +471,13 @@ _GLOBAL(kvmppc_resume_host) PPC_LL r3, HOST_RUN(r1) mr r5, r14 /* intno */ mr r14, r4 /* Save vcpu pointer. */ +#ifdef CONFIG_64BIT + /* Should we soft-disable interrupts? */ + andi. r6, r5, BOOKE_INTERRUPT_EXTERNAL | BOOKE_INTERRUPT_DECREMENTER | BOOKE_INTERRUPT_DOORBELL + beq skip_soft_dis + SOFT_DISABLE_INTS(r7,r8) +skip_soft_dis: +#endif bl kvmppc_handle_exit /* Restore vcpu pointer and the nonvolatiles we used. */ -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
