From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Graf Subject: Re: [PATCH 2/3] KVM: PPC: booke: Allow multiple exception types Date: Fri, 10 Aug 2012 11:19:08 +0200 Message-ID: <6764FCCA-6D01-4BC4-979E-B0B341914C5F@suse.de> References: <1343977723-25341-1-git-send-email-Bharat.Bhushan@freescale.com> <1343977723-25341-2-git-send-email-Bharat.Bhushan@freescale.com> <6A3DF150A5B70D4F9B66A25E3F7C888D03DF735F@039-SN2MPN1-022.039d.mgd.msft.net> Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Cc: "kvm-ppc@vger.kernel.org" , "kvm@vger.kernel.org" To: Bhushan Bharat-R65777 Return-path: In-Reply-To: <6A3DF150A5B70D4F9B66A25E3F7C888D03DF735F@039-SN2MPN1-022.039d.mgd.msft.net> Sender: kvm-ppc-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 10.08.2012, at 08:38, Bhushan Bharat-R65777 wrote: > > >> -----Original Message----- >> From: kvm-ppc-owner@vger.kernel.org [mailto:kvm-ppc-owner@vger.kernel.org] On >> Behalf Of Alexander Graf >> Sent: Tuesday, August 07, 2012 4:16 PM >> To: Bhushan Bharat-R65777 >> Cc: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 >> Subject: Re: [PATCH 2/3] KVM: PPC: booke: Allow multiple exception types >> >> >> On 03.08.2012, at 09:08, Bharat Bhushan wrote: >> >>> Current kvmppc_booke_handlers uses the same macro (KVM_HANDLER) and >>> all handlers are considered to be the same size. This will not be >>> the case if we want to use different macros for different handlers. >>> >>> This patch improves the kvmppc_booke_handler so that it can >>> support different macros for different handlers. >>> >>> Signed-off-by: Liu Yu >>> [bharat.bhushan@freescale.com: Substantial changes] >>> Signed-off-by: Bharat Bhushan >>> --- >>> arch/powerpc/include/asm/kvm_ppc.h | 2 - >>> arch/powerpc/kvm/booke.c | 9 ++++--- >>> arch/powerpc/kvm/booke.h | 1 + >>> arch/powerpc/kvm/booke_interrupts.S | 37 ++++++++++++++++++++++++++++++++-- >>> arch/powerpc/kvm/e500.c | 13 +++++++---- >>> 5 files changed, 48 insertions(+), 14 deletions(-) >>> >>> diff --git a/arch/powerpc/include/asm/kvm_ppc.h >> b/arch/powerpc/include/asm/kvm_ppc.h >>> index 1438a5e..deb55bd 100644 >>> --- a/arch/powerpc/include/asm/kvm_ppc.h >>> +++ b/arch/powerpc/include/asm/kvm_ppc.h >>> @@ -47,8 +47,6 @@ enum emulation_result { >>> >>> extern int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu); >>> extern int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu); >>> -extern char kvmppc_handlers_start[]; >>> -extern unsigned long kvmppc_handler_len; >>> extern void kvmppc_handler_highmem(void); >>> >>> extern void kvmppc_dump_vcpu(struct kvm_vcpu *vcpu); >>> diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c >>> index aebbb8b..1338233 100644 >>> --- a/arch/powerpc/kvm/booke.c >>> +++ b/arch/powerpc/kvm/booke.c >>> @@ -1541,6 +1541,7 @@ int __init kvmppc_booke_init(void) >>> { >>> #ifndef CONFIG_KVM_BOOKE_HV >>> unsigned long ivor[16]; >>> + unsigned long *handler = kvmppc_booke_handler_addr; >>> unsigned long max_ivor = 0; >>> int i; >>> >>> @@ -1574,14 +1575,14 @@ int __init kvmppc_booke_init(void) >>> >>> for (i = 0; i < 16; i++) { >>> if (ivor[i] > max_ivor) >>> - max_ivor = ivor[i]; >>> + max_ivor = i; >>> >>> memcpy((void *)kvmppc_booke_handlers + ivor[i], >>> - kvmppc_handlers_start + i * kvmppc_handler_len, >>> - kvmppc_handler_len); >>> + (void *)handler[i], handler[i + 1] - handler[i]); >>> } >>> flush_icache_range(kvmppc_booke_handlers, >>> - kvmppc_booke_handlers + max_ivor + kvmppc_handler_len); >>> + kvmppc_booke_handlers + ivor[max_ivor] + >>> + handler[max_ivor + 1] - handler[max_ivor]); >>> #endif /* !BOOKE_HV */ >>> return 0; >>> } >>> diff --git a/arch/powerpc/kvm/booke.h b/arch/powerpc/kvm/booke.h >>> index ba61974..de9e526 100644 >>> --- a/arch/powerpc/kvm/booke.h >>> +++ b/arch/powerpc/kvm/booke.h >>> @@ -65,6 +65,7 @@ >>> (1 << BOOKE_IRQPRIO_CRITICAL)) >>> >>> extern unsigned long kvmppc_booke_handlers; >>> +extern unsigned long kvmppc_booke_handler_addr[]; >>> >>> void kvmppc_set_msr(struct kvm_vcpu *vcpu, u32 new_msr); >>> void kvmppc_mmu_msr_notify(struct kvm_vcpu *vcpu, u32 old_msr); >>> diff --git a/arch/powerpc/kvm/booke_interrupts.S >> b/arch/powerpc/kvm/booke_interrupts.S >>> index bb46b32..3539805 100644 >>> --- a/arch/powerpc/kvm/booke_interrupts.S >>> +++ b/arch/powerpc/kvm/booke_interrupts.S >>> @@ -73,6 +73,14 @@ _GLOBAL(kvmppc_handler_\ivor_nr) >>> bctr >>> .endm >>> >>> +.macro KVM_HANDLER_ADDR ivor_nr >>> + .long kvmppc_handler_\ivor_nr >>> +.endm >>> + >>> +.macro KVM_HANDLER_END >>> + .long kvmppc_handlers_end >>> +.endm >>> + >>> _GLOBAL(kvmppc_handlers_start) >>> KVM_HANDLER BOOKE_INTERRUPT_CRITICAL SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_MACHINE_CHECK SPRN_SPRG_RSCRATCH_MC SPRN_MCSRR0 >>> @@ -93,9 +101,7 @@ KVM_HANDLER BOOKE_INTERRUPT_DEBUG SPRN_SPRG_RSCRATCH_CRIT >> SPRN_CSRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_SPE_UNAVAIL SPRN_SPRG_RSCRATCH0 SPRN_SRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_DATA SPRN_SPRG_RSCRATCH0 SPRN_SRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_ROUND SPRN_SPRG_RSCRATCH0 SPRN_SRR0 >>> - >>> -_GLOBAL(kvmppc_handler_len) >>> - .long kvmppc_handler_1 - kvmppc_handler_0 >>> +_GLOBAL(kvmppc_handlers_end) >>> >>> /* Registers: >>> * SPRG_SCRATCH0: guest r4 >>> @@ -463,6 +469,31 @@ lightweight_exit: >>> lwz r4, VCPU_GPR(R4)(r4) >>> rfi >>> >>> + .data >>> + .align 4 >>> + .globl kvmppc_booke_handler_addr >>> +kvmppc_booke_handler_addr: >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_CRITICAL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_MACHINE_CHECK >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DATA_STORAGE >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_INST_STORAGE >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_EXTERNAL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_ALIGNMENT >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_PROGRAM >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_FP_UNAVAIL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SYSCALL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_AP_UNAVAIL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DECREMENTER >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_FIT >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_WATCHDOG >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DTLB_MISS >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_ITLB_MISS >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DEBUG >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SPE_UNAVAIL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SPE_FP_DATA >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SPE_FP_ROUND >>> +KVM_HANDLER_END /*Always keep this in end*/ >>> + >>> #ifdef CONFIG_SPE >>> _GLOBAL(kvmppc_save_guest_spe) >>> cmpi 0,r3,0 >>> diff --git a/arch/powerpc/kvm/e500.c b/arch/powerpc/kvm/e500.c >>> index b479ed7..cb7a5e7 100644 >>> --- a/arch/powerpc/kvm/e500.c >>> +++ b/arch/powerpc/kvm/e500.c >>> @@ -491,12 +491,15 @@ static int __init kvmppc_e500_init(void) >>> { >>> int r, i; >>> unsigned long ivor[3]; >>> + unsigned long *handler = kvmppc_booke_handler_addr; >> >> /* Process remaining handlers above the generic first 16 */ >> unsigned long *handler = &kvmppc_booke_handler_addr[16]; >> >>> unsigned long max_ivor = 0; >>> >>> r = kvmppc_core_check_processor_compat(); >>> if (r) >>> return r; >>> >>> + handler += 16; >>> + >>> r = kvmppc_booke_init(); >>> if (r) >>> return r; >>> @@ -506,15 +509,15 @@ static int __init kvmppc_e500_init(void) >>> ivor[1] = mfspr(SPRN_IVOR33); >>> ivor[2] = mfspr(SPRN_IVOR34); >>> for (i = 0; i < 3; i++) { >>> - if (ivor[i] > max_ivor) >>> - max_ivor = ivor[i]; >>> + if (ivor[i] > ivor[max_ivor]) >>> + max_ivor = i; >>> >>> memcpy((void *)kvmppc_booke_handlers + ivor[i], >>> - kvmppc_handlers_start + (i + 16) * kvmppc_handler_len, >>> - kvmppc_handler_len); >>> + (void *)handler[i], handler[i + 1] - handler[i]); >> >> handler_len = handler[i + 1] - handler[i]; >> handler_end = max(handler_end, handler[i] + handler_len); > > Ok . > >> >>> } >>> flush_icache_range(kvmppc_booke_handlers, >>> - kvmppc_booke_handlers + max_ivor + kvmppc_handler_len); >>> + kvmppc_booke_handlers + ivor[max_ivor] + >>> + handler[max_ivor + 1] - handler[max_ivor]); >> >> handler_end > > I do not get how this logic will work and simple. Can you please explain ? > > The end address here is calculated by IVOR offset (same as host ivor offset) where KVM handler[last] is copied in kvmppc_booke_handlers and length by handler[last + 1] - handler[last]; Hrm. You want to flush from [ kvmppc_booke_handlers ; kvmppc_booke_handlers + handlers_len ]. handlers_len = handler[0] - handler_end; Alex From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Graf Date: Fri, 10 Aug 2012 09:19:08 +0000 Subject: Re: [PATCH 2/3] KVM: PPC: booke: Allow multiple exception types Message-Id: <6764FCCA-6D01-4BC4-979E-B0B341914C5F@suse.de> List-Id: References: <1343977723-25341-1-git-send-email-Bharat.Bhushan@freescale.com> <1343977723-25341-2-git-send-email-Bharat.Bhushan@freescale.com> <6A3DF150A5B70D4F9B66A25E3F7C888D03DF735F@039-SN2MPN1-022.039d.mgd.msft.net> In-Reply-To: <6A3DF150A5B70D4F9B66A25E3F7C888D03DF735F@039-SN2MPN1-022.039d.mgd.msft.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Bhushan Bharat-R65777 Cc: "kvm-ppc@vger.kernel.org" , "kvm@vger.kernel.org" On 10.08.2012, at 08:38, Bhushan Bharat-R65777 wrote: > > >> -----Original Message----- >> From: kvm-ppc-owner@vger.kernel.org [mailto:kvm-ppc-owner@vger.kernel.org] On >> Behalf Of Alexander Graf >> Sent: Tuesday, August 07, 2012 4:16 PM >> To: Bhushan Bharat-R65777 >> Cc: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 >> Subject: Re: [PATCH 2/3] KVM: PPC: booke: Allow multiple exception types >> >> >> On 03.08.2012, at 09:08, Bharat Bhushan wrote: >> >>> Current kvmppc_booke_handlers uses the same macro (KVM_HANDLER) and >>> all handlers are considered to be the same size. This will not be >>> the case if we want to use different macros for different handlers. >>> >>> This patch improves the kvmppc_booke_handler so that it can >>> support different macros for different handlers. >>> >>> Signed-off-by: Liu Yu >>> [bharat.bhushan@freescale.com: Substantial changes] >>> Signed-off-by: Bharat Bhushan >>> --- >>> arch/powerpc/include/asm/kvm_ppc.h | 2 - >>> arch/powerpc/kvm/booke.c | 9 ++++--- >>> arch/powerpc/kvm/booke.h | 1 + >>> arch/powerpc/kvm/booke_interrupts.S | 37 ++++++++++++++++++++++++++++++++-- >>> arch/powerpc/kvm/e500.c | 13 +++++++---- >>> 5 files changed, 48 insertions(+), 14 deletions(-) >>> >>> diff --git a/arch/powerpc/include/asm/kvm_ppc.h >> b/arch/powerpc/include/asm/kvm_ppc.h >>> index 1438a5e..deb55bd 100644 >>> --- a/arch/powerpc/include/asm/kvm_ppc.h >>> +++ b/arch/powerpc/include/asm/kvm_ppc.h >>> @@ -47,8 +47,6 @@ enum emulation_result { >>> >>> extern int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu); >>> extern int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu); >>> -extern char kvmppc_handlers_start[]; >>> -extern unsigned long kvmppc_handler_len; >>> extern void kvmppc_handler_highmem(void); >>> >>> extern void kvmppc_dump_vcpu(struct kvm_vcpu *vcpu); >>> diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c >>> index aebbb8b..1338233 100644 >>> --- a/arch/powerpc/kvm/booke.c >>> +++ b/arch/powerpc/kvm/booke.c >>> @@ -1541,6 +1541,7 @@ int __init kvmppc_booke_init(void) >>> { >>> #ifndef CONFIG_KVM_BOOKE_HV >>> unsigned long ivor[16]; >>> + unsigned long *handler = kvmppc_booke_handler_addr; >>> unsigned long max_ivor = 0; >>> int i; >>> >>> @@ -1574,14 +1575,14 @@ int __init kvmppc_booke_init(void) >>> >>> for (i = 0; i < 16; i++) { >>> if (ivor[i] > max_ivor) >>> - max_ivor = ivor[i]; >>> + max_ivor = i; >>> >>> memcpy((void *)kvmppc_booke_handlers + ivor[i], >>> - kvmppc_handlers_start + i * kvmppc_handler_len, >>> - kvmppc_handler_len); >>> + (void *)handler[i], handler[i + 1] - handler[i]); >>> } >>> flush_icache_range(kvmppc_booke_handlers, >>> - kvmppc_booke_handlers + max_ivor + kvmppc_handler_len); >>> + kvmppc_booke_handlers + ivor[max_ivor] + >>> + handler[max_ivor + 1] - handler[max_ivor]); >>> #endif /* !BOOKE_HV */ >>> return 0; >>> } >>> diff --git a/arch/powerpc/kvm/booke.h b/arch/powerpc/kvm/booke.h >>> index ba61974..de9e526 100644 >>> --- a/arch/powerpc/kvm/booke.h >>> +++ b/arch/powerpc/kvm/booke.h >>> @@ -65,6 +65,7 @@ >>> (1 << BOOKE_IRQPRIO_CRITICAL)) >>> >>> extern unsigned long kvmppc_booke_handlers; >>> +extern unsigned long kvmppc_booke_handler_addr[]; >>> >>> void kvmppc_set_msr(struct kvm_vcpu *vcpu, u32 new_msr); >>> void kvmppc_mmu_msr_notify(struct kvm_vcpu *vcpu, u32 old_msr); >>> diff --git a/arch/powerpc/kvm/booke_interrupts.S >> b/arch/powerpc/kvm/booke_interrupts.S >>> index bb46b32..3539805 100644 >>> --- a/arch/powerpc/kvm/booke_interrupts.S >>> +++ b/arch/powerpc/kvm/booke_interrupts.S >>> @@ -73,6 +73,14 @@ _GLOBAL(kvmppc_handler_\ivor_nr) >>> bctr >>> .endm >>> >>> +.macro KVM_HANDLER_ADDR ivor_nr >>> + .long kvmppc_handler_\ivor_nr >>> +.endm >>> + >>> +.macro KVM_HANDLER_END >>> + .long kvmppc_handlers_end >>> +.endm >>> + >>> _GLOBAL(kvmppc_handlers_start) >>> KVM_HANDLER BOOKE_INTERRUPT_CRITICAL SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_MACHINE_CHECK SPRN_SPRG_RSCRATCH_MC SPRN_MCSRR0 >>> @@ -93,9 +101,7 @@ KVM_HANDLER BOOKE_INTERRUPT_DEBUG SPRN_SPRG_RSCRATCH_CRIT >> SPRN_CSRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_SPE_UNAVAIL SPRN_SPRG_RSCRATCH0 SPRN_SRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_DATA SPRN_SPRG_RSCRATCH0 SPRN_SRR0 >>> KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_ROUND SPRN_SPRG_RSCRATCH0 SPRN_SRR0 >>> - >>> -_GLOBAL(kvmppc_handler_len) >>> - .long kvmppc_handler_1 - kvmppc_handler_0 >>> +_GLOBAL(kvmppc_handlers_end) >>> >>> /* Registers: >>> * SPRG_SCRATCH0: guest r4 >>> @@ -463,6 +469,31 @@ lightweight_exit: >>> lwz r4, VCPU_GPR(R4)(r4) >>> rfi >>> >>> + .data >>> + .align 4 >>> + .globl kvmppc_booke_handler_addr >>> +kvmppc_booke_handler_addr: >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_CRITICAL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_MACHINE_CHECK >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DATA_STORAGE >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_INST_STORAGE >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_EXTERNAL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_ALIGNMENT >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_PROGRAM >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_FP_UNAVAIL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SYSCALL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_AP_UNAVAIL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DECREMENTER >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_FIT >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_WATCHDOG >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DTLB_MISS >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_ITLB_MISS >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_DEBUG >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SPE_UNAVAIL >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SPE_FP_DATA >>> +KVM_HANDLER_ADDR BOOKE_INTERRUPT_SPE_FP_ROUND >>> +KVM_HANDLER_END /*Always keep this in end*/ >>> + >>> #ifdef CONFIG_SPE >>> _GLOBAL(kvmppc_save_guest_spe) >>> cmpi 0,r3,0 >>> diff --git a/arch/powerpc/kvm/e500.c b/arch/powerpc/kvm/e500.c >>> index b479ed7..cb7a5e7 100644 >>> --- a/arch/powerpc/kvm/e500.c >>> +++ b/arch/powerpc/kvm/e500.c >>> @@ -491,12 +491,15 @@ static int __init kvmppc_e500_init(void) >>> { >>> int r, i; >>> unsigned long ivor[3]; >>> + unsigned long *handler = kvmppc_booke_handler_addr; >> >> /* Process remaining handlers above the generic first 16 */ >> unsigned long *handler = &kvmppc_booke_handler_addr[16]; >> >>> unsigned long max_ivor = 0; >>> >>> r = kvmppc_core_check_processor_compat(); >>> if (r) >>> return r; >>> >>> + handler += 16; >>> + >>> r = kvmppc_booke_init(); >>> if (r) >>> return r; >>> @@ -506,15 +509,15 @@ static int __init kvmppc_e500_init(void) >>> ivor[1] = mfspr(SPRN_IVOR33); >>> ivor[2] = mfspr(SPRN_IVOR34); >>> for (i = 0; i < 3; i++) { >>> - if (ivor[i] > max_ivor) >>> - max_ivor = ivor[i]; >>> + if (ivor[i] > ivor[max_ivor]) >>> + max_ivor = i; >>> >>> memcpy((void *)kvmppc_booke_handlers + ivor[i], >>> - kvmppc_handlers_start + (i + 16) * kvmppc_handler_len, >>> - kvmppc_handler_len); >>> + (void *)handler[i], handler[i + 1] - handler[i]); >> >> handler_len = handler[i + 1] - handler[i]; >> handler_end = max(handler_end, handler[i] + handler_len); > > Ok . > >> >>> } >>> flush_icache_range(kvmppc_booke_handlers, >>> - kvmppc_booke_handlers + max_ivor + kvmppc_handler_len); >>> + kvmppc_booke_handlers + ivor[max_ivor] + >>> + handler[max_ivor + 1] - handler[max_ivor]); >> >> handler_end > > I do not get how this logic will work and simple. Can you please explain ? > > The end address here is calculated by IVOR offset (same as host ivor offset) where KVM handler[last] is copied in kvmppc_booke_handlers and length by handler[last + 1] - handler[last]; Hrm. You want to flush from [ kvmppc_booke_handlers ; kvmppc_booke_handlers + handlers_len ]. handlers_len = handler[0] - handler_end; Alex