| Message ID | 1342604355-22576-1-git-send-email-Bharat.Bhushan@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/18/2012 04:39 AM, Bharat Bhushan wrote: > This patch adds the watchdog emulation in KVM. The watchdog > emulation is enabled by KVM_ENABLE_CAP(KVM_CAP_PPC_WDT) ioctl. > The kernel timer are used for watchdog emulation and emulates > h/w watchdog state machine. On watchdog timer expiry, it exit to QEMU > if TCR.WRC is non ZERO. QEMU can reset/shutdown etc depending upon how > it is configured. > > Signed-off-by: Liu Yu <yu.liu@freescale.com> > Signed-off-by: Scott Wood <scottwood@freescale.com> > Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> Please put a note before your signoff stating that it's been modified since the previous signoffs, such as: [bharat.bhushan@freescale.com: reworked patch] > @@ -482,6 +484,7 @@ struct kvm_vcpu_arch { > u8 osi_needed; > u8 osi_enabled; > u8 papr_enabled; > + u8 watchdog_enable; s/enable;/enabled;/ > +static void arm_next_watchdog(struct kvm_vcpu *vcpu) > +{ > + unsigned long nr_jiffies; > + > + nr_jiffies = watchdog_next_timeout(vcpu); > + spin_lock(&vcpu->arch.wdt_lock); Do watchdog_next_timeout() from within the lock. > +void kvmppc_watchdog_func(unsigned long data) > +{ > + struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data; > + u32 tsr, new_tsr; > + int final; > + > + do { > + new_tsr = tsr = vcpu->arch.tsr; > + final = 0; > + > + /* Time out event */ > + if (tsr & TSR_ENW) { > + if (tsr & TSR_WIS) { > + final = 1; > + } else { > + new_tsr = tsr | TSR_WIS; > + } Unnecessary braces on the inner if/else. > + } else { > + new_tsr = tsr | TSR_ENW; > + } > + } while (cmpxchg(&vcpu->arch.tsr, tsr, new_tsr) != tsr); > + > + if (new_tsr & TSR_WIS) { > + smp_wmb(); > + kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu); > + kvm_vcpu_kick(vcpu); > + } > + > + /* > + * If this is final watchdog expiry and some action is required > + * then exit to userspace. > + */ > + if (final && (vcpu->arch.tcr & TCR_WRC_MASK)) { > + smp_wmb(); > + kvm_make_request(KVM_REQ_WATCHDOG, vcpu); > + kvm_vcpu_kick(vcpu); > + } > + > + > + /* > + * Stop running the watchdog timer after final expiration to > + * prevent the host from being flooded with timers if the > + * guest sets a short period. > + * Timers will resume when TSR/TCR is updated next time. > + */ > + if (!final) > + arm_next_watchdog(vcpu); > +} > static void update_timer_ints(struct kvm_vcpu *vcpu) Blank line between functions > static void kvmppc_core_check_exceptions(struct kvm_vcpu *vcpu) > @@ -516,6 +627,13 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) > goto out; > } > > + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && > + vcpu->arch.watchdog_enable) { Check .watchdog_enabled when you make the request, not here. > + kvm_run->exit_reason = KVM_EXIT_WATCHDOG; > + ret = 0; > + goto out; > + } I think we should check that ENW/WIS are still set. Now that we don't use TSR[WRS], this is the only way QEMU can preemptively clear a pending final expiration after leaving debug halt. If QEMU doesn't do this, and KVM comes back with a watchdog exit, QEMU won't know if it's a new legitimate one, or if it expired during the debug halt. This would be less ugly than QEMU doing a reset-TSR[WIS,ENW]-and-ignore on the first watchdog exit after a debug halt, and letting the expiration happen again if the guest is really stuck. > if (sregs->u.e.update_special & KVM_SREGS_E_UPDATE_TSR) { > + u32 old_tsr = vcpu->arch.tsr; > + > vcpu->arch.tsr = sregs->u.e.tsr; > + > + if ((old_tsr ^ vcpu->arch.tsr) & > + (TSR_ENW | TSR_WIS | TCR_WRC_MASK)) > + arm_next_watchdog(vcpu); Do we still do anything with TSR[WRS] at all? > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c > index 87f4dc8..3c50b81 100644 > --- a/arch/powerpc/kvm/powerpc.c > +++ b/arch/powerpc/kvm/powerpc.c > @@ -38,9 +38,11 @@ > > int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) > { > - return !(v->arch.shared->msr & MSR_WE) || > - !!(v->arch.pending_exceptions) || > - v->requests; > + bool ret = !(v->arch.shared->msr & MSR_WE) || > + !!(v->arch.pending_exceptions) || > + v->requests; > + > + return ret; > } There's no need to change this function anymore. > +#define KVM_CAP_PPC_WDT 81 s/WDT/WATCHDOG/ or better, s/WDT/BOOKE_WATCHDOG/ -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> -----Original Message----- > From: Wood Scott-B07421 > Sent: Thursday, July 19, 2012 7:56 AM > To: Bhushan Bharat-R65777 > Cc: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; agraf@suse.de; Bhushan Bharat- > R65777 > Subject: Re: [PATCH 2/2 v4] KVM: PPC: booke: Add watchdog emulation > > On 07/18/2012 04:39 AM, Bharat Bhushan wrote: > > This patch adds the watchdog emulation in KVM. The watchdog > > emulation is enabled by KVM_ENABLE_CAP(KVM_CAP_PPC_WDT) ioctl. > > The kernel timer are used for watchdog emulation and emulates > > h/w watchdog state machine. On watchdog timer expiry, it exit to QEMU > > if TCR.WRC is non ZERO. QEMU can reset/shutdown etc depending upon how > > it is configured. > > > > Signed-off-by: Liu Yu <yu.liu@freescale.com> > > Signed-off-by: Scott Wood <scottwood@freescale.com> > > Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> > > Please put a note before your signoff stating that it's been modified > since the previous signoffs, such as: > > [bharat.bhushan@freescale.com: reworked patch] > > > @@ -482,6 +484,7 @@ struct kvm_vcpu_arch { > > u8 osi_needed; > > u8 osi_enabled; > > u8 papr_enabled; > > + u8 watchdog_enable; > > s/enable;/enabled;/ > > > +static void arm_next_watchdog(struct kvm_vcpu *vcpu) > > +{ > > + unsigned long nr_jiffies; > > + > > + nr_jiffies = watchdog_next_timeout(vcpu); > > + spin_lock(&vcpu->arch.wdt_lock); > > Do watchdog_next_timeout() from within the lock. Why you think so? Is the next timeout calculation needed to be protected? > > > +void kvmppc_watchdog_func(unsigned long data) > > +{ > > + struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data; > > + u32 tsr, new_tsr; > > + int final; > > + > > + do { > > + new_tsr = tsr = vcpu->arch.tsr; > > + final = 0; > > + > > + /* Time out event */ > > + if (tsr & TSR_ENW) { > > + if (tsr & TSR_WIS) { > > + final = 1; > > + } else { > > + new_tsr = tsr | TSR_WIS; > > + } > > Unnecessary braces on the inner if/else. > > > + } else { > > + new_tsr = tsr | TSR_ENW; > > + } > > + } while (cmpxchg(&vcpu->arch.tsr, tsr, new_tsr) != tsr); > > + > > + if (new_tsr & TSR_WIS) { > > + smp_wmb(); > > + kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu); > > + kvm_vcpu_kick(vcpu); > > + } > > + > > + /* > > + * If this is final watchdog expiry and some action is required > > + * then exit to userspace. > > + */ > > + if (final && (vcpu->arch.tcr & TCR_WRC_MASK)) { > > + smp_wmb(); > > + kvm_make_request(KVM_REQ_WATCHDOG, vcpu); > > + kvm_vcpu_kick(vcpu); > > + } > > + > > + > > + /* > > + * Stop running the watchdog timer after final expiration to > > + * prevent the host from being flooded with timers if the > > + * guest sets a short period. > > + * Timers will resume when TSR/TCR is updated next time. > > + */ > > + if (!final) > > + arm_next_watchdog(vcpu); > > +} > > static void update_timer_ints(struct kvm_vcpu *vcpu) > > Blank line between functions > > > static void kvmppc_core_check_exceptions(struct kvm_vcpu *vcpu) > > @@ -516,6 +627,13 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct > kvm_vcpu *vcpu) > > goto out; > > } > > > > + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && > > + vcpu->arch.watchdog_enable) { > > Check .watchdog_enabled when you make the request, not here. > > > + kvm_run->exit_reason = KVM_EXIT_WATCHDOG; > > + ret = 0; > > + goto out; > > + } > > I think we should check that ENW/WIS are still set. Now that we don't > use TSR[WRS], this is the only way QEMU can preemptively clear a pending > final expiration after leaving debug halt. If QEMU doesn't do this, and > KVM comes back with a watchdog exit, QEMU won't know if it's a new > legitimate one, or if it expired during the debug halt. This would be > less ugly than QEMU doing a reset-TSR[WIS,ENW]-and-ignore on the first > watchdog exit after a debug halt, and letting the expiration happen > again if the guest is really stuck. ahh, What about clearing KVM_REQ_WATCHDOG request when QEMU clears ENW|WIS (or whenever KVM or QEMU clears ENW|WIS)? Thanks -Bharat > > > if (sregs->u.e.update_special & KVM_SREGS_E_UPDATE_TSR) { > > + u32 old_tsr = vcpu->arch.tsr; > > + > > vcpu->arch.tsr = sregs->u.e.tsr; > > + > > + if ((old_tsr ^ vcpu->arch.tsr) & > > + (TSR_ENW | TSR_WIS | TCR_WRC_MASK)) > > + arm_next_watchdog(vcpu); > > Do we still do anything with TSR[WRS] at all? > > > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c > > index 87f4dc8..3c50b81 100644 > > --- a/arch/powerpc/kvm/powerpc.c > > +++ b/arch/powerpc/kvm/powerpc.c > > @@ -38,9 +38,11 @@ > > > > int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) > > { > > - return !(v->arch.shared->msr & MSR_WE) || > > - !!(v->arch.pending_exceptions) || > > - v->requests; > > + bool ret = !(v->arch.shared->msr & MSR_WE) || > > + !!(v->arch.pending_exceptions) || > > + v->requests; > > + > > + return ret; > > } > > There's no need to change this function anymore. > > > +#define KVM_CAP_PPC_WDT 81 > > s/WDT/WATCHDOG/ > > or better, s/WDT/BOOKE_WATCHDOG/ > > -Scott
On 07/19/2012 12:35 AM, Bhushan Bharat-R65777 wrote: > > >> -----Original Message----- >> From: Wood Scott-B07421 >> Sent: Thursday, July 19, 2012 7:56 AM >> To: Bhushan Bharat-R65777 >> Cc: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; agraf@suse.de; Bhushan Bharat- >> R65777 >> Subject: Re: [PATCH 2/2 v4] KVM: PPC: booke: Add watchdog emulation >> >> On 07/18/2012 04:39 AM, Bharat Bhushan wrote: >>> This patch adds the watchdog emulation in KVM. The watchdog >>> emulation is enabled by KVM_ENABLE_CAP(KVM_CAP_PPC_WDT) ioctl. >>> The kernel timer are used for watchdog emulation and emulates >>> h/w watchdog state machine. On watchdog timer expiry, it exit to QEMU >>> if TCR.WRC is non ZERO. QEMU can reset/shutdown etc depending upon how >>> it is configured. >>> >>> Signed-off-by: Liu Yu <yu.liu@freescale.com> >>> Signed-off-by: Scott Wood <scottwood@freescale.com> >>> Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> >> >> Please put a note before your signoff stating that it's been modified >> since the previous signoffs, such as: >> >> [bharat.bhushan@freescale.com: reworked patch] >> >>> @@ -482,6 +484,7 @@ struct kvm_vcpu_arch { >>> u8 osi_needed; >>> u8 osi_enabled; >>> u8 papr_enabled; >>> + u8 watchdog_enable; >> >> s/enable;/enabled;/ >> >>> +static void arm_next_watchdog(struct kvm_vcpu *vcpu) >>> +{ >>> + unsigned long nr_jiffies; >>> + >>> + nr_jiffies = watchdog_next_timeout(vcpu); >>> + spin_lock(&vcpu->arch.wdt_lock); >> >> Do watchdog_next_timeout() from within the lock. > > Why you think so? Is the next timeout calculation needed to be protected? The point is to make sure that the timeout is still valid: CPU 0 CPU 1 arm_next_watchdog watchdog_next_timeout spin_lock update TCR arm_next_watchdog watchdog_next_timeout spin_lock mod timer spin_unlock lock acquired mod_timer spin_unlock In the above race, you'll end up with the watchdog armed based on the old TCR. >> I think we should check that ENW/WIS are still set. Now that we don't >> use TSR[WRS], this is the only way QEMU can preemptively clear a pending >> final expiration after leaving debug halt. If QEMU doesn't do this, and >> KVM comes back with a watchdog exit, QEMU won't know if it's a new >> legitimate one, or if it expired during the debug halt. This would be >> less ugly than QEMU doing a reset-TSR[WIS,ENW]-and-ignore on the first >> watchdog exit after a debug halt, and letting the expiration happen >> again if the guest is really stuck. > > ahh, What about clearing KVM_REQ_WATCHDOG request when QEMU clears > ENW|WIS (or whenever KVM or QEMU clears ENW|WIS)? Whichever's easier. -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 50ea12f..01047f4 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -467,6 +467,8 @@ struct kvm_vcpu_arch { ulong fault_esr; ulong queued_dear; ulong queued_esr; + spinlock_t wdt_lock; + struct timer_list wdt_timer; u32 tlbcfg[4]; u32 mmucfg; u32 epr; @@ -482,6 +484,7 @@ struct kvm_vcpu_arch { u8 osi_needed; u8 osi_enabled; u8 papr_enabled; + u8 watchdog_enable; u8 sane; u8 cpu_type; u8 hcall_needed; diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 0124937..e5cf4b9 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -67,6 +67,7 @@ extern int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu); extern void kvmppc_emulate_dec(struct kvm_vcpu *vcpu); extern u32 kvmppc_get_dec(struct kvm_vcpu *vcpu, u64 tb); extern void kvmppc_decrementer_func(unsigned long data); +extern void kvmppc_watchdog_func(unsigned long data); extern int kvmppc_sanity_check(struct kvm_vcpu *vcpu); /* Core-specific hooks */ @@ -104,6 +105,8 @@ extern void kvmppc_core_queue_external(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq); extern void kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq); +extern void kvmppc_core_queue_watchdog(struct kvm_vcpu *vcpu); +extern void kvmppc_core_dequeue_watchdog(struct kvm_vcpu *vcpu); extern int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned int op, int *advance); diff --git a/arch/powerpc/include/asm/reg_booke.h b/arch/powerpc/include/asm/reg_booke.h index 2d916c4..e07e6af 100644 --- a/arch/powerpc/include/asm/reg_booke.h +++ b/arch/powerpc/include/asm/reg_booke.h @@ -539,6 +539,13 @@ #define TCR_FIE 0x00800000 /* FIT Interrupt Enable */ #define TCR_ARE 0x00400000 /* Auto Reload Enable */ +#ifdef CONFIG_E500 +#define TCR_GET_WP(tcr) ((((tcr) & 0xC0000000) >> 30) | \ + (((tcr) & 0x1E0000) >> 15)) +#else +#define TCR_GET_WP(tcr) (((tcr) & 0xC0000000) >> 30) +#endif + /* Bit definitions for the TSR. */ #define TSR_ENW 0x80000000 /* Enable Next Watchdog */ #define TSR_WIS 0x40000000 /* WDT Interrupt Status */ diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index d25a097..9682506 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -206,6 +206,16 @@ void kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu, clear_bit(BOOKE_IRQPRIO_EXTERNAL_LEVEL, &vcpu->arch.pending_exceptions); } +void kvmppc_core_queue_watchdog(struct kvm_vcpu *vcpu) +{ + kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_WATCHDOG); +} + +void kvmppc_core_dequeue_watchdog(struct kvm_vcpu *vcpu) +{ + clear_bit(BOOKE_IRQPRIO_WATCHDOG, &vcpu->arch.pending_exceptions); +} + static void set_guest_srr(struct kvm_vcpu *vcpu, unsigned long srr0, u32 srr1) { #ifdef CONFIG_KVM_BOOKE_HV @@ -325,6 +335,7 @@ static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, msr_mask = MSR_CE | MSR_ME | MSR_DE; int_class = INT_CLASS_NONCRIT; break; + case BOOKE_IRQPRIO_WATCHDOG: case BOOKE_IRQPRIO_CRITICAL: case BOOKE_IRQPRIO_DBELL_CRIT: allowed = vcpu->arch.shared->msr & MSR_CE; @@ -404,12 +415,112 @@ static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, return allowed; } +/* + * Return the number of jiffies until the next timeout. If the timeout is + * longer than the NEXT_TIMER_MAX_DELTA, then return NEXT_TIMER_MAX_DELTA + * because the larger value can break the timer APIs. + */ +static unsigned long watchdog_next_timeout(struct kvm_vcpu *vcpu) +{ + u64 tb, wdt_tb, wdt_ticks = 0; + u64 nr_jiffies = 0; + u32 period = TCR_GET_WP(vcpu->arch.tcr); + + wdt_tb = 1ULL << (63 - period); + tb = get_tb(); + /* + * The watchdog timeout will hapeen when TB bit corresponding + * to watchdog will toggle from 0 to 1. + */ + if (tb & wdt_tb) + wdt_ticks = wdt_tb; + + wdt_ticks += wdt_tb - (tb & (wdt_tb - 1)); + + /* Convert timebase ticks to jiffies */ + nr_jiffies = wdt_ticks; + + if (do_div(nr_jiffies, tb_ticks_per_jiffy)) + nr_jiffies++; + + return min_t(unsigned long long, nr_jiffies, NEXT_TIMER_MAX_DELTA); +} + +static void arm_next_watchdog(struct kvm_vcpu *vcpu) +{ + unsigned long nr_jiffies; + + nr_jiffies = watchdog_next_timeout(vcpu); + spin_lock(&vcpu->arch.wdt_lock); + /* + * If the number of jiffies of watchdog timer >= NEXT_TIMER_MAX_DELTA + * then do not run the watchdog timer as this can break timer APIs. + */ + if (nr_jiffies < NEXT_TIMER_MAX_DELTA) + mod_timer(&vcpu->arch.wdt_timer, jiffies + nr_jiffies); + else + del_timer(&vcpu->arch.wdt_timer); + spin_unlock(&vcpu->arch.wdt_lock); +} + +void kvmppc_watchdog_func(unsigned long data) +{ + struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data; + u32 tsr, new_tsr; + int final; + + do { + new_tsr = tsr = vcpu->arch.tsr; + final = 0; + + /* Time out event */ + if (tsr & TSR_ENW) { + if (tsr & TSR_WIS) { + final = 1; + } else { + new_tsr = tsr | TSR_WIS; + } + } else { + new_tsr = tsr | TSR_ENW; + } + } while (cmpxchg(&vcpu->arch.tsr, tsr, new_tsr) != tsr); + + if (new_tsr & TSR_WIS) { + smp_wmb(); + kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu); + kvm_vcpu_kick(vcpu); + } + + /* + * If this is final watchdog expiry and some action is required + * then exit to userspace. + */ + if (final && (vcpu->arch.tcr & TCR_WRC_MASK)) { + smp_wmb(); + kvm_make_request(KVM_REQ_WATCHDOG, vcpu); + kvm_vcpu_kick(vcpu); + } + + /* + * Stop running the watchdog timer after final expiration to + * prevent the host from being flooded with timers if the + * guest sets a short period. + * Timers will resume when TSR/TCR is updated next time. + */ + if (!final) + arm_next_watchdog(vcpu); +} static void update_timer_ints(struct kvm_vcpu *vcpu) { if ((vcpu->arch.tcr & TCR_DIE) && (vcpu->arch.tsr & TSR_DIS)) kvmppc_core_queue_dec(vcpu); else kvmppc_core_dequeue_dec(vcpu); + + if ((vcpu->arch.tcr & TCR_WIE) && (vcpu->arch.tsr & TSR_WIS)) + kvmppc_core_queue_watchdog(vcpu); + else + kvmppc_core_dequeue_watchdog(vcpu); } static void kvmppc_core_check_exceptions(struct kvm_vcpu *vcpu) @@ -516,6 +627,13 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) goto out; } + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && + vcpu->arch.watchdog_enable) { + kvm_run->exit_reason = KVM_EXIT_WATCHDOG; + ret = 0; + goto out; + } + kvm_guest_enter(); #ifdef CONFIG_PPC_FPU @@ -978,6 +1096,12 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, } } + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && + vcpu->arch.watchdog_enable) { + run->exit_reason = KVM_EXIT_WATCHDOG; + r = RESUME_HOST | (r & RESUME_FLAG_NV); + } + return r; } @@ -1106,7 +1230,14 @@ static int set_sregs_base(struct kvm_vcpu *vcpu, } if (sregs->u.e.update_special & KVM_SREGS_E_UPDATE_TSR) { + u32 old_tsr = vcpu->arch.tsr; + vcpu->arch.tsr = sregs->u.e.tsr; + + if ((old_tsr ^ vcpu->arch.tsr) & + (TSR_ENW | TSR_WIS | TCR_WRC_MASK)) + arm_next_watchdog(vcpu); + update_timer_ints(vcpu); } @@ -1267,6 +1398,7 @@ void kvmppc_core_commit_memory_region(struct kvm *kvm, void kvmppc_set_tcr(struct kvm_vcpu *vcpu, u32 new_tcr) { vcpu->arch.tcr = new_tcr; + arm_next_watchdog(vcpu); update_timer_ints(vcpu); } @@ -1281,6 +1413,14 @@ void kvmppc_set_tsr_bits(struct kvm_vcpu *vcpu, u32 tsr_bits) void kvmppc_clr_tsr_bits(struct kvm_vcpu *vcpu, u32 tsr_bits) { clear_bits(tsr_bits, &vcpu->arch.tsr); + + /* + * We may have stopped the watchdog due to + * being stuck on final expiration. + */ + if (tsr_bits & (TSR_ENW | TSR_WIS | TCR_WRC_MASK)) + arm_next_watchdog(vcpu); + update_timer_ints(vcpu); } diff --git a/arch/powerpc/kvm/booke_emulate.c b/arch/powerpc/kvm/booke_emulate.c index 12834bb..5a66ade 100644 --- a/arch/powerpc/kvm/booke_emulate.c +++ b/arch/powerpc/kvm/booke_emulate.c @@ -145,6 +145,14 @@ int kvmppc_booke_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val) kvmppc_clr_tsr_bits(vcpu, spr_val); break; case SPRN_TCR: + /* + * WRC is a 2-bit field that is supposed to preserve its + * value once written to non-zero. + */ + if (vcpu->arch.tcr & TCR_WRC_MASK) { + spr_val &= ~TCR_WRC_MASK; + spr_val |= vcpu->arch.tcr & TCR_WRC_MASK; + } kvmppc_set_tcr(vcpu, spr_val); break; diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 87f4dc8..3c50b81 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -38,9 +38,11 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) { - return !(v->arch.shared->msr & MSR_WE) || - !!(v->arch.pending_exceptions) || - v->requests; + bool ret = !(v->arch.shared->msr & MSR_WE) || + !!(v->arch.pending_exceptions) || + v->requests; + + return ret; } int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) @@ -237,6 +239,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_PPC_GET_PVINFO: #if defined(CONFIG_KVM_E500V2) || defined(CONFIG_KVM_E500MC) case KVM_CAP_SW_TLB: + case KVM_CAP_PPC_WDT: #endif r = 1; break; @@ -386,13 +389,23 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) #ifdef CONFIG_KVM_EXIT_TIMING mutex_init(&vcpu->arch.exit_timing_lock); #endif - +#ifdef CONFIG_BOOKE + spin_lock_init(&vcpu->arch.wdt_lock); + /* setup watchdog timer once */ + setup_timer(&vcpu->arch.wdt_timer, kvmppc_watchdog_func, + (unsigned long)vcpu); +#endif return 0; } void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) { kvmppc_mmu_destroy(vcpu); +#ifdef CONFIG_BOOKE + spin_lock(&vcpu->arch.wdt_lock); + del_timer(&vcpu->arch.wdt_timer); + spin_unlock(&vcpu->arch.wdt_lock); +#endif } void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) @@ -637,6 +650,12 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu, r = 0; vcpu->arch.papr_enabled = true; break; +#ifdef CONFIG_BOOKE + case KVM_CAP_PPC_WDT: + r = 0; + vcpu->arch.watchdog_enable = true; + break; +#endif #if defined(CONFIG_KVM_E500V2) || defined(CONFIG_KVM_E500MC) case KVM_CAP_SW_TLB: { struct kvm_config_tlb cfg; diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 2ce09aa..07dcab3 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -163,6 +163,7 @@ struct kvm_pit_config { #define KVM_EXIT_OSI 18 #define KVM_EXIT_PAPR_HCALL 19 #define KVM_EXIT_S390_UCONTROL 20 +#define KVM_EXIT_WATCHDOG 21 /* For KVM_EXIT_INTERNAL_ERROR */ #define KVM_INTERNAL_ERROR_EMULATION 1 @@ -618,6 +619,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_PPC_GET_SMMU_INFO 78 #define KVM_CAP_S390_COW 79 #define KVM_CAP_PPC_ALLOC_HTAB 80 +#define KVM_CAP_PPC_WDT 81 #ifdef KVM_CAP_IRQ_ROUTING diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 27ac8a4..41d32be 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -69,6 +69,7 @@ #define KVM_REQ_IMMEDIATE_EXIT 15 #define KVM_REQ_PMU 16 #define KVM_REQ_PMI 17 +#define KVM_REQ_WATCHDOG 18 #define KVM_USERSPACE_IRQ_SOURCE_ID 0