Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 01.02.2013, at 10:07, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, February 01, 2013 1:36 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 01.02.2013, at 06:04, Bhushan Bharat-R65777 wrote: -Original Message- From: kvm-ppc-ow...@vger.kernel.org [mailto:kvm-ppc-ow...@vger.kernel.org] On Behalf Of Alexander Graf Sent: Thursday, January 31, 2013 10:38 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We always set MSR_DE in hw MSR when qemu using the debug resource. In the _guest_ MSR, yes. But once we exit the guest, it shouldn't be set anymore, because we're in an interrupt handler, no? Or is MSR_DE kept alive on interrupts? During the exit code path, you could then swap DBSR back to what the host expects (which means no single step). Only after that enable MSR_DE again. We do not support deferred debug
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 07.02.2013, at 15:48, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We always set MSR_DE in hw MSR when qemu using the debug resource. In the _guest_ MSR, yes. But once we exit the guest, it shouldn't be set anymore, because we're in an interrupt handler, no? Or is MSR_DE kept alive on interrupts? During the exit code path, you could then swap DBSR back to what the host expects (which means no single step). Only after that enable MSR_DE again. We do not support deferred debug interrupt, so we do save restore dbsr. +1: /* debug interrupt happened
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We always set MSR_DE in hw MSR when qemu using the debug resource. In the _guest_ MSR, yes. But once we exit the guest, it shouldn't be set anymore, because we're in an interrupt handler, no? Or is MSR_DE kept alive on interrupts? During the exit code path, you could then swap DBSR back to what the host expects (which means no single step). Only after that enable MSR_DE again. We do not support deferred debug
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 01.02.2013, at 06:04, Bhushan Bharat-R65777 wrote: -Original Message- From: kvm-ppc-ow...@vger.kernel.org [mailto:kvm-ppc-ow...@vger.kernel.org] On Behalf Of Alexander Graf Sent: Thursday, January 31, 2013 10:38 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, February 01, 2013 1:36 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 01.02.2013, at 06:04, Bhushan Bharat-R65777 wrote: -Original Message- From: kvm-ppc-ow...@vger.kernel.org [mailto:kvm-ppc-ow...@vger.kernel.org] On Behalf Of Alexander Graf Sent: Thursday, January 31, 2013 10:38 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 01.02.2013, at 06:04, Bhushan Bharat-R65777 wrote: -Original Message- From: kvm-ppc-ow...@vger.kernel.org [mailto:kvm-ppc-ow...@vger.kernel.org] On Behalf Of Alexander Graf Sent: Thursday, January 31, 2013 10:38 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, February 01, 2013 1:36 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 01.02.2013, at 06:04, Bhushan Bharat-R65777 wrote: -Original Message- From: kvm-ppc-ow...@vger.kernel.org [mailto:kvm-ppc-ow...@vger.kernel.org] On Behalf Of Alexander Graf Sent: Thursday, January 31, 2013 10:38 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. During the exit code path, you could then swap DBSR back to what the host expects (which means no single step). Only after that enable MSR_DE again. +1: /* debug interrupt happened in guest */ + mtcrr3 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + lwz r3, VCPU_CRIT_SAVE(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 I don't think you need the __KVM_HANDLER split. This should be quite easily refactorable into a simple DBG prolog. Can you please
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++--- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We always set MSR_DE in hw MSR when qemu using the debug resource. During the exit code path, you could then swap DBSR back to what the host expects (which means no single step). Only after that enable MSR_DE again. We
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++--- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We always set MSR_DE in hw MSR when qemu using the debug resource. In the _guest_ MSR, yes. But once we exit the guest, it shouldn't be set anymore, because we're in an interrupt handler, no? Or is MSR_DE kept alive on interrupts? During the exit code path, you
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 31.01.2013, at 18:08, Alexander Graf wrote: On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++--- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; +u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); +DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) -/* Get pointer to vcpu and record exit number. */ -mtspr \scratch , r4 -mfspr r4, SPRN_SPRG_THREAD -lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) +/* Get pointer to vcpu and record exit number. */ +mtspr \scratch , r4 +mfspr r4, SPRN_SPRG_THREAD +lwz r4, THREAD_KVM_VCPU(r4) +__KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) +mtspr \scratch, r4 +mfspr r4, SPRN_SPRG_THREAD +lwz r4, THREAD_KVM_VCPU(r4) +stw r3, VCPU_CRIT_SAVE(r4) +mfcrr3 +mfspr r4, SPRN_CSRR1 +andi. r4, r4, MSR_PR +bne 1f +/* debug interrupt happened in enter/exit path */ +mfspr r4, SPRN_CSRR1 +rlwinm r4, r4, 0, ~MSR_DE +mtspr SPRN_CSRR1, r4 +lis r4, 0x +ori r4, r4, 0x +mtspr SPRN_DBSR, r4 +mfspr r4, SPRN_SPRG_THREAD +lwz r4, THREAD_KVM_VCPU(r4) +mtcrr3 +lwz r3, VCPU_CRIT_SAVE(r4) +mfspr r4, \scratch +rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: kvm-ppc-ow...@vger.kernel.org [mailto:kvm-ppc-ow...@vger.kernel.org] On Behalf Of Alexander Graf Sent: Thursday, January 31, 2013 10:38 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. During the exit code path, you could then swap DBSR back to what the host expects (which means no single step). Only after that enable MSR_DE again. +1: /* debug interrupt happened in guest */ + mtcrr3 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + lwz r3, VCPU_CRIT_SAVE(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 I don't think you need the __KVM_HANDLER split. This should be quite easily refactorable into a simple DBG prolog. Can you please
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++--- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We always set MSR_DE in hw MSR when qemu using the debug resource. In the _guest_ MSR, yes. But once we exit the guest, it shouldn't be set anymore, because we're in an interrupt handler, no? Or is MSR_DE kept alive on interrupts? During the exit code path, you
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 31.01.2013, at 18:08, Alexander Graf wrote: On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++--- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; +u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); +DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) -/* Get pointer to vcpu and record exit number. */ -mtspr \scratch , r4 -mfspr r4, SPRN_SPRG_THREAD -lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) +/* Get pointer to vcpu and record exit number. */ +mtspr \scratch , r4 +mfspr r4, SPRN_SPRG_THREAD +lwz r4, THREAD_KVM_VCPU(r4) +__KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) +mtspr \scratch, r4 +mfspr r4, SPRN_SPRG_THREAD +lwz r4, THREAD_KVM_VCPU(r4) +stw r3, VCPU_CRIT_SAVE(r4) +mfcrr3 +mfspr r4, SPRN_CSRR1 +andi. r4, r4, MSR_PR +bne 1f +/* debug interrupt happened in enter/exit path */ +mfspr r4, SPRN_CSRR1 +rlwinm r4, r4, 0, ~MSR_DE +mtspr SPRN_CSRR1, r4 +lis r4, 0x +ori r4, r4, 0x +mtspr SPRN_DBSR, r4 +mfspr r4, SPRN_SPRG_THREAD +lwz r4, THREAD_KVM_VCPU(r4) +mtcrr3 +lwz r3, VCPU_CRIT_SAVE(r4) +mfspr r4, \scratch +rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. Right, but why is MSR_DE enabled during the exit path? If MSR_DE wasn't set, you wouldn't get a single step exit. We
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: kvm-ppc-ow...@vger.kernel.org [mailto:kvm-ppc-ow...@vger.kernel.org] On Behalf Of Alexander Graf Sent: Thursday, January 31, 2013 10:38 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 31.01.2013, at 17:58, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Thursday, January 31, 2013 5:47 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 30.01.2013, at 12:30, Bhushan Bharat-R65777 wrote: -Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- -- -- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, +arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-...@vger.kernel.org; kvm@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. +1: /* debug interrupt happened in guest */ + mtcrr3 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + lwz r3, VCPU_CRIT_SAVE(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 I don't think you need the __KVM_HANDLER split. This should be quite easily refactorable into a simple DBG prolog. Can you please elaborate how you are envisioning this? Thanks -Bharat Alex +.endm + .macro KVM_HANDLER_ADDR ivor_nr .long kvmppc_handler_\ivor_nr .endm @@ -98,7 +133,7 @@ KVM_HANDLER BOOKE_INTERRUPT_FIT SPRN_SPRG_RSCRATCH0 SPRN_SRR0
RE: [PATCH 3/8] KVM: PPC: booke: Added debug handler
-Original Message- From: Alexander Graf [mailto:ag...@suse.de] Sent: Friday, January 25, 2013 5:13 PM To: Bhushan Bharat-R65777 Cc: kvm-ppc@vger.kernel.org; k...@vger.kernel.org; Bhushan Bharat-R65777 Subject: Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 .endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? As BOOKE doesn't have hardware support for virtualization, hardware never know current pc is in guest or in host. So when enable hardware single step for guest, it cannot be disabled at the time guest exit. Thus, we'll see that an single step interrupt happens at the beginning of guest exit path. With the above code we recognize this kind of single step interrupt disable single step and rfci. Why would we have MSR_DE enabled in the first place when we can't handle it? When QEMU is using hardware debug resource then we always set MSR_DE during guest is running. +1: /* debug interrupt happened in guest */ + mtcrr3 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + lwz r3, VCPU_CRIT_SAVE(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 I don't think you need the __KVM_HANDLER split. This should be quite easily refactorable into a simple DBG prolog. Can you please elaborate how you are envisioning this? Thanks -Bharat Alex +.endm + .macro KVM_HANDLER_ADDR ivor_nr .long kvmppc_handler_\ivor_nr .endm @@ -98,7 +133,7 @@ KVM_HANDLER BOOKE_INTERRUPT_FIT SPRN_SPRG_RSCRATCH0 SPRN_SRR0
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 +.endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? Why would we have MSR_DE enabled in the first place when we can't handle it? +1: /* debug interrupt happened in guest */ + mtcrr3 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + lwz r3, VCPU_CRIT_SAVE(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 I don't think you need the __KVM_HANDLER split. This should be quite easily refactorable into a simple DBG prolog. Alex +.endm + .macro KVM_HANDLER_ADDR ivor_nr .long kvmppc_handler_\ivor_nr .endm @@ -98,7 +133,7 @@ KVM_HANDLER BOOKE_INTERRUPT_FIT SPRN_SPRG_RSCRATCH0 SPRN_SRR0 KVM_HANDLER BOOKE_INTERRUPT_WATCHDOG SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0 KVM_HANDLER BOOKE_INTERRUPT_DTLB_MISS SPRN_SPRG_RSCRATCH0 SPRN_SRR0 KVM_HANDLER BOOKE_INTERRUPT_ITLB_MISS SPRN_SPRG_RSCRATCH0 SPRN_SRR0 -KVM_HANDLER BOOKE_INTERRUPT_DEBUG SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0 +KVM_DBG_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 -- 1.7.0.4 -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 3/8] KVM: PPC: booke: Added debug handler
On 16.01.2013, at 09:24, Bharat Bhushan wrote: From: Bharat Bhushan bharat.bhus...@freescale.com Installed debug handler will be used for guest debug support and debug facility emulation features (patches for these features will follow this patch). Signed-off-by: Liu Yu yu@freescale.com [bharat.bhus...@freescale.com: Substantial changes] Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- arch/powerpc/include/asm/kvm_host.h |1 + arch/powerpc/kernel/asm-offsets.c |1 + arch/powerpc/kvm/booke_interrupts.S | 49 ++- 3 files changed, 44 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8a72d59..f4ba881 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -503,6 +503,7 @@ struct kvm_vcpu_arch { u32 tlbcfg[4]; u32 mmucfg; u32 epr; + u32 crit_save; struct kvmppc_booke_debug_reg dbg_reg; #endif gpa_t paddr_accessed; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 46f6afd..02048f3 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -562,6 +562,7 @@ int main(void) DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst)); DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear)); DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr)); + DEFINE(VCPU_CRIT_SAVE, offsetof(struct kvm_vcpu, arch.crit_save)); #endif /* CONFIG_PPC_BOOK3S */ #endif /* CONFIG_KVM */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index eae8483..dd9c5d4 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -52,12 +52,7 @@ (1BOOKE_INTERRUPT_PROGRAM) | \ (1BOOKE_INTERRUPT_DTLB_MISS)) -.macro KVM_HANDLER ivor_nr scratch srr0 -_GLOBAL(kvmppc_handler_\ivor_nr) - /* Get pointer to vcpu and record exit number. */ - mtspr \scratch , r4 - mfspr r4, SPRN_SPRG_THREAD - lwz r4, THREAD_KVM_VCPU(r4) +.macro __KVM_HANDLER ivor_nr scratch srr0 stw r3, VCPU_GPR(R3)(r4) stw r5, VCPU_GPR(R5)(r4) stw r6, VCPU_GPR(R6)(r4) @@ -74,6 +69,46 @@ _GLOBAL(kvmppc_handler_\ivor_nr) bctr .endm +.macro KVM_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + /* Get pointer to vcpu and record exit number. */ + mtspr \scratch , r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 +.endm + +.macro KVM_DBG_HANDLER ivor_nr scratch srr0 +_GLOBAL(kvmppc_handler_\ivor_nr) + mtspr \scratch, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + stw r3, VCPU_CRIT_SAVE(r4) + mfcrr3 + mfspr r4, SPRN_CSRR1 + andi. r4, r4, MSR_PR + bne 1f + /* debug interrupt happened in enter/exit path */ + mfspr r4, SPRN_CSRR1 + rlwinm r4, r4, 0, ~MSR_DE + mtspr SPRN_CSRR1, r4 + lis r4, 0x + ori r4, r4, 0x + mtspr SPRN_DBSR, r4 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + mtcrr3 + lwz r3, VCPU_CRIT_SAVE(r4) + mfspr r4, \scratch + rfci What is this part doing? Try to ignore the debug exit? Why would we have MSR_DE enabled in the first place when we can't handle it? +1: /* debug interrupt happened in guest */ + mtcrr3 + mfspr r4, SPRN_SPRG_THREAD + lwz r4, THREAD_KVM_VCPU(r4) + lwz r3, VCPU_CRIT_SAVE(r4) + __KVM_HANDLER \ivor_nr \scratch \srr0 I don't think you need the __KVM_HANDLER split. This should be quite easily refactorable into a simple DBG prolog. Alex +.endm + .macro KVM_HANDLER_ADDR ivor_nr .long kvmppc_handler_\ivor_nr .endm @@ -98,7 +133,7 @@ KVM_HANDLER BOOKE_INTERRUPT_FIT SPRN_SPRG_RSCRATCH0 SPRN_SRR0 KVM_HANDLER BOOKE_INTERRUPT_WATCHDOG SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0 KVM_HANDLER BOOKE_INTERRUPT_DTLB_MISS SPRN_SPRG_RSCRATCH0 SPRN_SRR0 KVM_HANDLER BOOKE_INTERRUPT_ITLB_MISS SPRN_SPRG_RSCRATCH0 SPRN_SRR0 -KVM_HANDLER BOOKE_INTERRUPT_DEBUG SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0 +KVM_DBG_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 -- 1.7.0.4 -- 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