Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47 +--
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest */
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] = kvmppc_get_gpr(vcpu,
3 + i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send privileged
@@ -1016,22 +1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
kvm_vcpu *vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
This looks odd. Your exit reason only changes when you do the hcall exiting,
right?
You also need to guard user space hcall exits with an ENABLE_CAP. Otherwise
older user space will break, as it doesn't know about the exit type yet.
Alex
break;
+ }
#else
- case BOOKE_INTERRUPT_SYSCALL:
+ case BOOKE_INTERRUPT_SYSCALL: {
+ int i;
+ r = RESUME_GUEST;
if (!(vcpu-arch.shared-msr MSR_PR)
(((u32)kvmppc_get_gpr(vcpu, 0)) == KVM_SC_MAGIC_R0)) {
/* KVM PV hypercalls */
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
- r = RESUME_GUEST;
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest */
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] = kvmppc_get_gpr(vcpu,
3 + i);
+ vcpu-arch.hcall_needed = 1;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
+ r = RESUME_HOST;
} else {
/* Guest syscalls */
kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_SYSCALL);
}
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
- r = RESUME_GUEST;
break;
+ }
#endif
case BOOKE_INTERRUPT_DTLB_MISS: {
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 4e05f8c..6c6199d 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -307,6 +307,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_PPC_BOOKE_SREGS:
case KVM_CAP_PPC_BOOKE_WATCHDOG:
case KVM_CAP_PPC_EPR:
+ case KVM_CAP_EXIT_EPAPR_HCALL:
#else
case KVM_CAP_PPC_SEGSTATE:
case KVM_CAP_PPC_HIOR:
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 01ee50e..b5266e5 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -674,6 +674,7 @@ struct kvm_ppc_smmu_info {
#define KVM_CAP_PPC_RTAS 91
#define KVM_CAP_IRQ_XICS 92
RE: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+--
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest */
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] = kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send privileged @@
-1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu
*vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the hcall exiting,
right?
You also need to guard user space hcall exits with an ENABLE_CAP. Otherwise
older user space will break, as it doesn't know about the exit type yet.
So the user space so make enable_cap also?
-Bharat
Alex
break;
+ }
#else
- case BOOKE_INTERRUPT_SYSCALL:
+ case BOOKE_INTERRUPT_SYSCALL: {
+ int i;
+ r = RESUME_GUEST;
if (!(vcpu-arch.shared-msr MSR_PR)
(((u32)kvmppc_get_gpr(vcpu, 0)) == KVM_SC_MAGIC_R0)) {
/* KVM PV hypercalls */
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
- r = RESUME_GUEST;
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest */
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] = kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
+ r = RESUME_HOST;
} else {
/* Guest syscalls */
kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_SYSCALL);
}
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
- r = RESUME_GUEST;
break;
+ }
#endif
case BOOKE_INTERRUPT_DTLB_MISS: {
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 4e05f8c..6c6199d 100644
--- a/arch/powerpc/kvm/powerpc.c
+++
Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
On 15.07.2013, at 13:38, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+--
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest */
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] = kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send privileged @@
-1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu
*vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the hcall exiting,
right?
You also need to guard user space hcall exits with an ENABLE_CAP. Otherwise
older user space will break, as it doesn't know about the exit type yet.
So the user space so make enable_cap also?
User space needs to call enable_cap on this cap, yes. Otherwise a guest can
confuse user space with an hcall exit it can't handle.
Alex
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To unsubscribe from this list: send the line unsubscribe kvm-ppc in
the body of a message to majord...@vger.kernel.org
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RE: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:16 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 13:38, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421;
Yoder Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+-
-
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run,
struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest */
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] = kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send privileged @@
-1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
+kvm_vcpu *vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the hcall
exiting, right?
You also need to guard user space hcall exits with an ENABLE_CAP.
Otherwise older user space will break, as it doesn't know about the exit
type
yet.
So the user space so make enable_cap also?
User space needs to call enable_cap on this cap, yes. Otherwise a guest can
confuse user space with an hcall exit it can't handle.
We do not have enable_cap for book3s, any specific reason why ?
-Bharat
Alex
--
To unsubscribe from this list: send the line unsubscribe kvm-ppc in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
On 15.07.2013, at 16:50, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:16 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 13:38, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421;
Yoder Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+-
-
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run,
struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest */
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] = kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send privileged @@
-1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
+kvm_vcpu *vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the hcall
exiting, right?
You also need to guard user space hcall exits with an ENABLE_CAP.
Otherwise older user space will break, as it doesn't know about the exit
type
yet.
So the user space so make enable_cap also?
User space needs to call enable_cap on this cap, yes. Otherwise a guest can
confuse user space with an hcall exit it can't handle.
We do not have enable_cap for book3s, any specific reason why ?
We do. If you enable PAPR, you get PAPR hcalls. If you enable OSI, you get OSI
hcalls. KVM hcalls on book3s don't return to user space. Which is something we
probably want to change along with this patch set.
Alex
--
To unsubscribe from this list: send the line unsubscribe kvm-ppc in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 8:27 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 16:50, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:16 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421;
Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:38, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood
Scott-B07421; Yoder Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+---
--
-
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run,
struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own
function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest
*/
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls
in kvm
*/
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] =
kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send
privileged @@ -1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
+kvm_vcpu *vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the hcall
exiting, right?
You also need to guard user space hcall exits with an ENABLE_CAP.
Otherwise older user space will break, as it doesn't know about the
exit type
yet.
So the user space so make enable_cap also?
User space needs to call enable_cap on this cap, yes. Otherwise a
guest can confuse user space with an hcall exit it can't handle.
We do not have enable_cap for book3s, any specific reason why ?
We do. If you enable PAPR, you get PAPR hcalls. If you enable OSI, you get OSI
hcalls.
Oh, We check this on book3s_PR and book3s_HV.
KVM hcalls on book3s don't return to user space.
It exits, is not it? arch/powerpc/kvm/book3s_pr.c exits with
KVM_EXIT_PAPR_HCALL. And same in book3s_pv.
Btw, Adding this on booke is not a question. I am just understanding book3s.
-Bharat
Which is something we
probably want to change along with this patch set.
Alex
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Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
On 15.07.2013, at 17:13, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 8:27 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 16:50, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:16 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421;
Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:38, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood
Scott-B07421; Yoder Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+---
--
-
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run,
struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own
function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest
*/
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls
in kvm
*/
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] =
kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send
privileged @@ -1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
+kvm_vcpu *vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the hcall
exiting, right?
You also need to guard user space hcall exits with an ENABLE_CAP.
Otherwise older user space will break, as it doesn't know about the
exit type
yet.
So the user space so make enable_cap also?
User space needs to call enable_cap on this cap, yes. Otherwise a
guest can confuse user space with an hcall exit it can't handle.
We do not have enable_cap for book3s, any specific reason why ?
We do. If you enable PAPR, you get PAPR hcalls. If you enable OSI, you get
OSI
hcalls.
Oh, We check this on book3s_PR and book3s_HV.
KVM hcalls on book3s don't return to user space.
It exits, is not it? arch/powerpc/kvm/book3s_pr.c exits with
KVM_EXIT_PAPR_HCALL. And same in book3s_pv.
It doesn't even start handling the hcall if papr_enabled isn't set ;).
Alex
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RE: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 8:59 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 17:13, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 8:27 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421;
Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 16:50, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:16 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood
Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:38, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood
Scott-B07421; Yoder Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+-
--
--
-
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run
*run, struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own
function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest
*/
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls
in kvm
*/
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] =
kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send
privileged @@ -
1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
+kvm_vcpu *vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the
hcall exiting, right?
You also need to guard user space hcall exits with an ENABLE_CAP.
Otherwise older user space will break, as it doesn't know about
the exit type
yet.
So the user space so make enable_cap also?
User space needs to call enable_cap on this cap, yes. Otherwise a
guest can confuse user space with an hcall exit it can't handle.
We do not have enable_cap for book3s, any specific reason why ?
We do. If you enable PAPR, you get PAPR hcalls. If you enable OSI,
you get OSI hcalls.
Oh, We check this on book3s_PR and book3s_HV.
KVM hcalls on book3s don't return to user space.
It exits, is not it? arch/powerpc/kvm/book3s_pr.c exits with
KVM_EXIT_PAPR_HCALL. And same in book3s_pv.
It doesn't even start
Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
On 15.07.2013, at 17:35, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 8:59 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 15.07.2013, at 17:13, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 8:27 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood Scott-B07421;
Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 16:50, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:16 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood
Scott-B07421; Yoder
Stuart-B08248
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:38, Bhushan Bharat-R65777 wrote:
-Original Message-
From: Alexander Graf [mailto:ag...@suse.de]
Sent: Monday, July 15, 2013 5:02 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; Wood
Scott-B07421; Yoder Stuart-B08248; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for
unimplemented hcalls in kvm
On 15.07.2013, at 13:11, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+-
--
--
-
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run
*run, struct
kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
This is getting large. Please extract hcall handling into its own
function.
Maybe you can merge the HV and non-HV case then too.
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest
*/
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls
in kvm
*/
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] =
kvmppc_get_gpr(vcpu,
3 +
i);
+ vcpu-arch.hcall_needed = 1;
+ kvmppc_account_exit(vcpu, SYSCALL_EXITS);
+ r = RESUME_HOST;
} else {
/*
* hcall from guest userspace -- send
privileged @@ -
1016,22
+1032,39 @@ int kvmppc_handle_exit(struct kvm_run *run, struct
+kvm_vcpu *vcpu,
kvmppc_core_queue_program(vcpu, ESR_PPR);
}
- r = RESUME_GUEST;
+ run-exit_reason = KVM_EXIT_EPAPR_HCALL;
Oops, what I have done, I wanted this to be
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
s/ run-exit_reason = KVM_EXIT_EPAPR_HCALL;/
kvmppc_account_exit(vcpu, SYSCALL_EXITS);
-Bharat
This looks odd. Your exit reason only changes when you do the
hcall exiting, right?
You also need to guard user space hcall exits with an ENABLE_CAP.
Otherwise older user space will break, as it doesn't know about
the exit type
yet.
So the user space so make enable_cap also?
User space needs to call enable_cap on this cap, yes. Otherwise a
guest can confuse user space with an hcall exit it can't handle.
We do not have enable_cap for book3s, any specific reason why ?
We do. If you enable PAPR, you get PAPR hcalls. If you enable OSI,
you get OSI hcalls.
Oh, We check this on book3s_PR and book3s_HV.
KVM hcalls on book3s don't return to user space.
It exits, is not it? arch/powerpc/kvm/book3s_pr.c exits with
KVM_EXIT_PAPR_HCALL. And same in book3s_pv.
It doesn't even start handling the hcall if papr_enabled isn't set ;).
On
Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
On 07/15/2013 06:11:16 AM, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+--
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run,
struct kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+/* except unimplemented return to guest
*/
+ kvmppc_set_gpr(vcpu, 3, r);
+kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls
in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+run-epapr_hcall.args[i] =
kvmppc_get_gpr(vcpu, 3 + i);
You need to clear the upper half of each register if CONFIG_PPC64=y and
MSR_CM is not set.
+ vcpu-arch.hcall_needed = 1;
The existing code for hcall_needed restores 9 return arguments, rather
than the 8 that are defined for this interface. Thus, you'll be
restoring one word of padding into the guest -- which could be
arbitrary userspace data that shouldn't be leaked. r12 is volatile in
the ePAPR hcall ABI so simply clobbering it isn't a problem, though.
-Scott
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More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: [PATCH 2/5] booke: exit to guest userspace for unimplemented hcalls in kvm
-Original Message-
From: Wood Scott-B07421
Sent: Monday, July 15, 2013 11:38 PM
To: Bhushan Bharat-R65777
Cc: k...@vger.kernel.org; kvm-ppc@vger.kernel.org; ag...@suse.de; Yoder
Stuart-
B08248; Bhushan Bharat-R65777; Bhushan Bharat-R65777
Subject: Re: [PATCH 2/5] booke: exit to guest userspace for unimplemented
hcalls
in kvm
On 07/15/2013 06:11:16 AM, Bharat Bhushan wrote:
Exit to guest user space if kvm does not implement the hcall.
Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com
---
arch/powerpc/kvm/booke.c | 47
+--
arch/powerpc/kvm/powerpc.c |1 +
include/uapi/linux/kvm.h |1 +
3 files changed, 42 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index
17722d8..c8b41b4 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1005,9 +1005,25 @@ int kvmppc_handle_exit(struct kvm_run *run,
struct kvm_vcpu *vcpu,
break;
#ifdef CONFIG_KVM_BOOKE_HV
- case BOOKE_INTERRUPT_HV_SYSCALL:
+ case BOOKE_INTERRUPT_HV_SYSCALL: {
+ int i;
if (!(vcpu-arch.shared-msr MSR_PR)) {
- kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+ r = kvmppc_kvm_pv(vcpu);
+ if (r != EV_UNIMPLEMENTED) {
+ /* except unimplemented return to guest
*/
+ kvmppc_set_gpr(vcpu, 3, r);
+ kvmppc_account_exit(vcpu,
SYSCALL_EXITS);
+ r = RESUME_GUEST;
+ break;
+ }
+ /* Exit to userspace for unimplemented hcalls
in kvm */
+ run-epapr_hcall.nr = kvmppc_get_gpr(vcpu, 11);
+ run-epapr_hcall.ret = 0;
+ for (i = 0; i 8; i++)
+ run-epapr_hcall.args[i] =
kvmppc_get_gpr(vcpu, 3 + i);
You need to clear the upper half of each register if CONFIG_PPC64=y and MSR_CM
is not set.
+ vcpu-arch.hcall_needed = 1;
The existing code for hcall_needed restores 9 return arguments, rather than
the
8 that are defined for this interface. Thus, you'll be restoring one word of
padding into the guest -- which could be arbitrary userspace data that
shouldn't
be leaked. r12 is volatile in the ePAPR hcall ABI so simply clobbering it
isn't
a problem, though.
Oops; Not just that, currently this uses struct type papr_hcall while on
booke we should use epapr_hcall. I will make a function which will be defined
in book3s.c and booke.c to setup hcall return registers accordingly.
-Bharat
-Scott
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