[PATCH] target/ppc: Fix wrong interpretation of the disposition flag.

2020-04-08 Thread Ganesh Goudar
[ 20.653310] Bus error [ 20.655575] MCE: CPU0: machine check (Harmless) Host UE Indeterminate [Not recovered] [ 20.655575] MCE: CPU0: NIP: [c008023a00e8] mcetest_tlbie+0xe8/0xf0 [mcetest_tlbie] [ 20.655576] MCE: CPU0: Initiator CPU [ 20.655576] MCE: CPU0: Unknown Signed-off-by: G

[PATCH v21 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls

2020-01-30 Thread Ganesh Goudar
check error waits till the first processor is done reading the error log. The first processor issues "ibm,nmi-interlock" call when the error log is consumed. Signed-off-by: Aravinda Prasad [Register fwnmi RTAS calls in core_rtas_register_types() where other RTAS calls are registered] Si

[PATCH v21 7/7] ppc: spapr: Activate the FWNMI functionality

2020-01-30 Thread Ganesh Goudar
From: Aravinda Prasad This patch sets the default value of SPAPR_CAP_FWNMI_MCE to SPAPR_CAP_ON for machine type 5.0. Signed-off-by: Aravinda Prasad Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 5 - 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc

[PATCH v21 4/7] target/ppc: Build rtas error log upon an MCE

2020-01-30 Thread Ganesh Goudar
. For recoverable errors, the guest performs recovery actions and logs the error. Signed-off-by: Aravinda Prasad [Assume SLOF has allocated enough room for rtas error log] Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson --- hw/ppc/spapr_events.c | 220

[PATCH v21 1/7] Wrapper function to wait on condition for the main loop mutex

2020-01-30 Thread Ganesh Goudar
-by: Aravinda Prasad Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson Reviewed-by: Greg Kurz --- cpus.c | 5 + include/qemu/main-loop.h | 8 2 files changed, 13 insertions(+) diff --git a/cpus.c b/cpus.c index b612116f95..b4f8b84b61 100644 --- a/cpus.c +++ b

[PATCH v21 2/7] ppc: spapr: Introduce FWNMI capability

2020-01-30 Thread Ganesh Goudar
to migration state and reprhase the commit message] Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson --- hw/ppc/spapr.c | 2 ++ hw/ppc/spapr_caps.c| 18 ++ include/hw/ppc/spapr.h | 5 - target/ppc/kvm.c | 8 target/ppc/kvm_ppc.h | 6

[PATCH v21 6/7] migration: Include migration support for machine check handling

2020-01-30 Thread Ganesh Goudar
-by: Aravinda Prasad [Do not set FWNMI cap in post_load, now its done in .apply hook] Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 47 ++ hw/ppc/spapr_events.c | 16 +- hw/ppc/spapr_rtas.c| 2 ++ include/hw/ppc/spapr.h | 2

[PATCH v21 3/7] target/ppc: Handle NMI guest exit

2020-01-30 Thread Ganesh Goudar
reason set to KVM_EXIT_NMI in such cases. This patch handles KVM_EXIT_NMI exit. [1] https://www.spinics.net/lists/kvm-ppc/msg12637.html (e20bbd3d and related commits) Signed-off-by: Aravinda Prasad Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson Reviewed-by: Greg Kurz --- hw/ppc

[PATCH v21 0/7]target-ppc/spapr: Add FWNMI support in QEMU for PowerKVM guests

2020-01-30 Thread Ganesh Goudar
This patch set adds support for FWNMI in PowerKVM guests. System errors such as SLB multihit and memory errors that cannot be corrected by hardware is passed on to the kernel for handling by raising machine check exception (an NMI). Upon such machine check exceptions, if the address in error

[PATCH v20 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls

2020-01-17 Thread Ganesh Goudar
check error waits till the first processor is done reading the error log. The first processor issues "ibm,nmi-interlock" call when the error log is consumed. Signed-off-by: Aravinda Prasad [Register fwnmi RTAS calls in core_rtas_register_types() where other RTAS calls are registered] Si

[PATCH v20 4/7] target/ppc: Build rtas error log upon an MCE

2020-01-17 Thread Ganesh Goudar
. For recoverable errors, the guest performs recovery actions and logs the error. Signed-off-by: Aravinda Prasad [Assume SLOF has allocated enough room for rtas error log] Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson --- hw/ppc/spapr_events.c | 220

[PATCH v20 3/7] target/ppc: Handle NMI guest exit

2020-01-17 Thread Ganesh Goudar
reason set to KVM_EXIT_NMI in such cases. This patch handles KVM_EXIT_NMI exit. [1] https://www.spinics.net/lists/kvm-ppc/msg12637.html (e20bbd3d and related commits) Signed-off-by: Aravinda Prasad Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson Reviewed-by: Greg Kurz --- hw/ppc

[PATCH v20 2/7] ppc: spapr: Introduce FWNMI capability

2020-01-17 Thread Ganesh Goudar
to migration state and reprhase the commit message] Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 2 ++ hw/ppc/spapr_caps.c| 18 ++ include/hw/ppc/spapr.h | 5 - target/ppc/kvm.c | 8 target/ppc/kvm_ppc.h | 6 ++ 5 files changed, 38

[PATCH v20 7/7] ppc: spapr: Activate the FWNMI functionality

2020-01-17 Thread Ganesh Goudar
From: Aravinda Prasad This patch sets the default value of SPAPR_CAP_FWNMI_MCE to SPAPR_CAP_ON for machine type 4.2. Signed-off-by: Aravinda Prasad Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc

[PATCH v20 6/7] migration: Include migration support for machine check handling

2020-01-17 Thread Ganesh Goudar
-by: Aravinda Prasad [Do not set FWNMI cap in post_load, now its done in .apply hook] Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 47 ++ hw/ppc/spapr_events.c | 16 +- hw/ppc/spapr_rtas.c| 2 ++ include/hw/ppc/spapr.h | 2

[PATCH v20 1/7] Wrapper function to wait on condition for the main loop mutex

2020-01-17 Thread Ganesh Goudar
-by: Aravinda Prasad Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson Reviewed-by: Greg Kurz --- cpus.c | 5 + include/qemu/main-loop.h | 8 2 files changed, 13 insertions(+) diff --git a/cpus.c b/cpus.c index be2d655f37..c06a2ad20b 100644 --- a/cpus.c +++ b

[PATCH v20 0/7]target-ppc/spapr: Add FWNMI support in QEMU for PowerKVM guests

2020-01-17 Thread Ganesh Goudar
This patch set adds support for FWNMI in PowerKVM guests. System errors such as SLB multihit and memory errors that cannot be corrected by hardware is passed on to the kernel for handling by raising machine check exception (an NMI). Upon such machine check exceptions, if the address in error

[PATCH v19 7/7] ppc: spapr: Activate the FWNMI functionality

2020-01-16 Thread Ganesh Goudar
From: Aravinda Prasad This patch sets the default value of SPAPR_CAP_FWNMI_MCE to SPAPR_CAP_ON for machine type 4.2. Signed-off-by: Aravinda Prasad Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc

[PATCH v19 6/7] migration: Include migration support for machine check handling

2020-01-16 Thread Ganesh Goudar
-by: Aravinda Prasad [Do not set FWNMI cap in post_load, now its done in .apply hook] Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 47 ++ hw/ppc/spapr_events.c | 16 +- hw/ppc/spapr_rtas.c| 4 include/hw/ppc/spapr.h | 2

[PATCH v19 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls

2020-01-16 Thread Ganesh Goudar
check error waits till the first processor is done reading the error log. The first processor issues "ibm,nmi-interlock" call when the error log is consumed. Signed-off-by: Aravinda Prasad [Register fwnmi RTAS calls in core_rtas_register_types() where other RTAS calls are registered] Si

[PATCH v19 1/7] Wrapper function to wait on condition for the main loop mutex

2020-01-16 Thread Ganesh Goudar
-by: Aravinda Prasad Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson Reviewed-by: Greg Kurz --- cpus.c | 5 + include/qemu/main-loop.h | 8 2 files changed, 13 insertions(+) diff --git a/cpus.c b/cpus.c index be2d655f37..c06a2ad20b 100644 --- a/cpus.c +++ b

[PATCH v19 3/7] target/ppc: Handle NMI guest exit

2020-01-16 Thread Ganesh Goudar
reason set to KVM_EXIT_NMI in such cases. This patch handles KVM_EXIT_NMI exit. [1] https://www.spinics.net/lists/kvm-ppc/msg12637.html (e20bbd3d and related commits) Signed-off-by: Aravinda Prasad Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson Reviewed-by: Greg Kurz --- hw/ppc

[PATCH v19 4/7] target/ppc: Build rtas error log upon an MCE

2020-01-16 Thread Ganesh Goudar
. For recoverable errors, the guest performs recovery actions and logs the error. Signed-off-by: Aravinda Prasad [Assume SLOF has allocated enough room for rtas error log] Signed-off-by: Ganesh Goudar Reviewed-by: David Gibson --- hw/ppc/spapr_events.c | 220

[PATCH v19 2/7] ppc: spapr: Introduce FWNMI capability

2020-01-16 Thread Ganesh Goudar
to migration state and reprhase the commit message] Signed-off-by: Ganesh Goudar --- hw/ppc/spapr.c | 2 ++ hw/ppc/spapr_caps.c| 18 ++ include/hw/ppc/spapr.h | 5 - target/ppc/kvm.c | 8 target/ppc/kvm_ppc.h | 6 ++ 5 files changed, 38

[PATCH v19 0/7]target-ppc/spapr: Add FWNMI support in QEMU for PowerKM guests

2020-01-16 Thread Ganesh Goudar
This patch set adds support for FWNMI in PowerKVM guests. System errors such as SLB multihit and memory errors that cannot be corrected by hardware is passed on to the kernel for handling by raising machine check exception (an NMI). Upon such machine check exceptions, if the address in error

[PATCH v18 3/7] target/ppc: Handle NMI guest exit

2020-01-01 Thread Ganesh Goudar
From: Aravinda Prasad Memory error such as bit flips that cannot be corrected by hardware are passed on to the kernel for handling. If the memory address in error belongs to guest then the guest kernel is responsible for taking suitable action. Patch [1] enhances KVM to exit guest with exit

[PATCH v18 7/7] ppc: spapr: Activate the FWNMI functionality

2020-01-01 Thread Ganesh Goudar
From: Aravinda Prasad This patch sets the default value of SPAPR_CAP_FWNMI_MCE to SPAPR_CAP_ON for machine type 4.2. Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index

[PATCH v18 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls

2020-01-01 Thread Ganesh Goudar
check error waits till the first processor is done reading the error log. The first processor issues "ibm,nmi-interlock" call when the error log is consumed. [Move fwnmi registration to .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw

[PATCH v18 1/7] Wrapper function to wait on condition for the main loop mutex

2020-01-01 Thread Ganesh Goudar
From: Aravinda Prasad Introduce a wrapper function to wait on condition for the main loop mutex. This function atomically releases the main loop mutex and causes the calling thread to block on the condition. This wrapper is required because qemu_global_mutex is a static variable. Signed-off-by:

[PATCH v18 6/7] migration: Include migration support for machine check handling

2020-01-01 Thread Ganesh Goudar
FWNMI cap in post_load, now its done in .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 41 + hw/ppc/spapr_events.c | 20 +++- hw/ppc/spapr_rtas.c| 4 include/hw/ppc/spapr.h

[PATCH v18 2/7] ppc: spapr: Introduce FWNMI capability

2020-01-01 Thread Ganesh Goudar
From: Aravinda Prasad Introduce fwnmi an spapr capability and validate it against the kernels existing capability by trying to enable it. [eliminate cap_ppc_fwnmi, add fwnmi cap to migration state and reprhase the commit message] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad

[PATCH v18 0/7] target-ppc/spapr: Add FWNMI support in QEMU for PowerKM guests

2020-01-01 Thread Ganesh Goudar
This patch set adds support for FWNMI in PowerKVM guests. System errors such as SLB multihit and memory errors that cannot be corrected by hardware is passed on to the kernel for handling by raising machine check exception (an NMI). Upon such machine check exceptions, if the address in error

[PATCH v18 4/7] target/ppc: Build rtas error log upon an MCE

2020-01-01 Thread Ganesh Goudar
. For recoverable errors, the guest performs recovery actions and logs the error. [Assume SLOF has allocated enough room for rtas error log] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad Reviewed-by: David Gibson --- hw/ppc/spapr_events.c | 220

[PATCH v17 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls

2019-10-24 Thread Ganesh Goudar
check error waits till the first processor is done reading the error log. The first processor issues "ibm,nmi-interlock" call when the error log is consumed. [Move fwnmi registeration to .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/p

[PATCH v17 2/7] ppc: spapr: Introduce FWNMI capability

2019-10-24 Thread Ganesh Goudar
From: Aravinda Prasad Introduce fwnmi an spapr capability and validate it against the kernels existing capability by trying to enable it. [eliminate cap_ppc_fwnmi, add fwnmi cap to migration state and reprhase the commit message] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad

[PATCH v17 1/7] Wrapper function to wait on condition for the main loop mutex

2019-10-24 Thread Ganesh Goudar
From: Aravinda Prasad Introduce a wrapper function to wait on condition for the main loop mutex. This function atomically releases the main loop mutex and causes the calling thread to block on the condition. This wrapper is required because qemu_global_mutex is a static variable. Signed-off-by:

[PATCH v17 7/7] ppc: spapr: Activate the FWNMI functionality

2019-10-24 Thread Ganesh Goudar
From: Aravinda Prasad This patch sets the default value of SPAPR_CAP_FWNMI_MCE to SPAPR_CAP_ON for machine type 4.2. Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index

[PATCH v17 3/7] target/ppc: Handle NMI guest exit

2019-10-24 Thread Ganesh Goudar
From: Aravinda Prasad Memory error such as bit flips that cannot be corrected by hardware are passed on to the kernel for handling. If the memory address in error belongs to guest then the guest kernel is responsible for taking suitable action. Patch [1] enhances KVM to exit guest with exit

[PATCH v17 6/7] migration: Include migration support for machine check handling

2019-10-24 Thread Ganesh Goudar
FWNMI cap in post_load, now its done in .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 41 + hw/ppc/spapr_events.c | 16 +++- hw/ppc/spapr_rtas.c| 2 ++ include/hw/ppc/spapr.h | 2

[PATCH v17 4/7] target/ppc: Build rtas error log upon an MCE

2019-10-24 Thread Ganesh Goudar
. For recoverable errors, the guest performs recovery actions and logs the error. [Assume SLOF has allocated enough room for rtas error log] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/ppc/spapr_events.c | 220 - hw/ppc/spapr_rtas.c

[PATCH v17 0/7] target-ppc/spapr: Add FWNMI support in QEMU for PowerKM guests

2019-10-24 Thread Ganesh Goudar
This patch set adds support for FWNMI in PowerKVM guests. System errors such as SLB multihit and memory errors that cannot be corrected by hardware is passed on to the kernel for handling by raising machine check exception (an NMI). Upon such machine check exceptions, if the address in error

[PATCH v16 6/7] migration: Include migration support for machine check handling

2019-10-10 Thread Ganesh Goudar
FWNMI cap in post_load, now its done in .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 41 + hw/ppc/spapr_events.c | 16 +++- hw/ppc/spapr_rtas.c| 2 ++ include/hw/ppc/spapr.h | 2

[PATCH v16 7/7] ppc: spapr: Activate the FWNMI functionality

2019-10-10 Thread Ganesh Goudar
From: Aravinda Prasad This patch sets the default value of SPAPR_CAP_FWNMI_MCE to SPAPR_CAP_ON for machine type 4.2. Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index

[PATCH v16 3/7] target/ppc: Handle NMI guest exit

2019-10-10 Thread Ganesh Goudar
From: Aravinda Prasad Memory error such as bit flips that cannot be corrected by hardware are passed on to the kernel for handling. If the memory address in error belongs to guest then the guest kernel is responsible for taking suitable action. Patch [1] enhances KVM to exit guest with exit

[PATCH v16 2/7] ppc: spapr: Introduce FWNMI capability

2019-10-10 Thread Ganesh Goudar
0x200 vector. This patch also introduces fwnmi-mce capability to deal with the case when a guest with the KVM_CAP_PPC_FWNMI capability enabled is attempted to migrate to a host that does not support this capability. [eliminate cap_ppc_fwnmi] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad

[PATCH v16 4/7] target/ppc: Build rtas error log upon an MCE

2019-10-10 Thread Ganesh Goudar
. For recoverable errors, the guest performs recovery actions and logs the error. [Assume SLOF has allocated enough room for rtas error log] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/ppc/spapr_events.c | 220 - hw/ppc/spapr_rtas.c

[PATCH v16 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls

2019-10-10 Thread Ganesh Goudar
check error waits till the first processor is done reading the error log. The first processor issues "ibm,nmi-interlock" call when the error log is consumed. [Move fwnmi registeration to .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/p

[PATCH v16 0/7] target-ppc/spapr: Add FWNMI support in QEMU for PowerKVM guests

2019-10-10 Thread Ganesh Goudar
This patch set adds support for FWNMI in PowerKVM guests. System errors such as SLB multihit and memory errors that cannot be corrected by hardware is passed on to the kernel for handling by raising machine check exception (an NMI). Upon such machine check exceptions, if the address in error

[PATCH v16 1/7] Wrapper function to wait on condition for the main loop mutex

2019-10-10 Thread Ganesh Goudar
From: Aravinda Prasad Introduce a wrapper function to wait on condition for the main loop mutex. This function atomically releases the main loop mutex and causes the calling thread to block on the condition. This wrapper is required because qemu_global_mutex is a static variable. Signed-off-by:

[PATCH v15 7/7] ppc: spapr: Activate the FWNMI functionality

2019-10-09 Thread Ganesh Goudar
From: Aravinda Prasad This patch sets the default value of SPAPR_CAP_FWNMI_MCE to SPAPR_CAP_ON for machine type 4.2. Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index

[PATCH v15 1/7] Wrapper function to wait on condition for the main loop mutex

2019-10-09 Thread Ganesh Goudar
From: Aravinda Prasad Introduce a wrapper function to wait on condition for the main loop mutex. This function atomically releases the main loop mutex and causes the calling thread to block on the condition. This wrapper is required because qemu_global_mutex is a static variable. Signed-off-by:

[PATCH v15 0/7] target-ppc/spapr: Add FWNMI support in QEMU for PowerKVM guests

2019-10-09 Thread Ganesh Goudar
This patch set adds support for FWNMI in PowerKVM guests. System errors such as SLB multihit and memory errors that cannot be corrected by hardware is passed on to the kernel for handling by raising machine check exception (an NMI). Upon such machine check exceptions, if the address in error

[PATCH v15 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls

2019-10-09 Thread Ganesh Goudar
check error waits till the first processor is done reading the error log. The first processor issues "ibm,nmi-interlock" call when the error log is consumed. [Move fwnmi registeration to .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/p

[PATCH v15 4/7] target/ppc: Build rtas error log upon an MCE

2019-10-09 Thread Ganesh Goudar
. For recoverable errors, the guest performs recovery actions and logs the error. [Assume SLOF has allocated enough room for rtas error log] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/ppc/spapr_events.c | 220 - hw/ppc/spapr_rtas.c

[PATCH v15 2/7] ppc: spapr: Introduce FWNMI capability

2019-10-09 Thread Ganesh Goudar
0x200 vector. This patch also introduces fwnmi-mce capability to deal with the case when a guest with the KVM_CAP_PPC_FWNMI capability enabled is attempted to migrate to a host that does not support this capability. [eliminate cap_ppc_fwnmi] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad

[PATCH v15 6/7] migration: Include migration support for machine check handling

2019-10-09 Thread Ganesh Goudar
FWNMI cap in post_load, now its done in .apply hook] Signed-off-by: Ganesh Goudar Signed-off-by: Aravinda Prasad --- hw/ppc/spapr.c | 41 + hw/ppc/spapr_events.c | 16 +++- hw/ppc/spapr_rtas.c| 2 ++ include/hw/ppc/spapr.h | 2

[PATCH v15 3/7] target/ppc: Handle NMI guest exit

2019-10-09 Thread Ganesh Goudar
From: Aravinda Prasad Memory error such as bit flips that cannot be corrected by hardware are passed on to the kernel for handling. If the memory address in error belongs to guest then the guest kernel is responsible for taking suitable action. Patch [1] enhances KVM to exit guest with exit