* [PULL 1/6] KVM: s390: diagnose call documentation
2013-12-11 18:57 [PULL 0/6] KVM: s390: patches for kvm-next Cornelia Huck
@ 2013-12-11 18:57 ` Cornelia Huck
2013-12-11 18:57 ` [PULL 2/6] KVM: s390: Use helper function to set CC in SIGP handler Cornelia Huck
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Cornelia Huck @ 2013-12-11 18:57 UTC (permalink / raw)
To: Gleb Natapov, Paolo Bonzini
Cc: Christian Borntraeger, kvm, linux-s390, Cornelia Huck
Add some further documentation on the DIAGNOSE calls we support.
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
Documentation/virtual/kvm/hypercalls.txt | 3 ++
Documentation/virtual/kvm/s390-diag.txt | 80 ++++++++++++++++++++++++++++++
2 files changed, 83 insertions(+)
create mode 100644 Documentation/virtual/kvm/s390-diag.txt
diff --git a/Documentation/virtual/kvm/hypercalls.txt b/Documentation/virtual/kvm/hypercalls.txt
index 022198e..d922d73 100644
--- a/Documentation/virtual/kvm/hypercalls.txt
+++ b/Documentation/virtual/kvm/hypercalls.txt
@@ -17,6 +17,9 @@ S390:
S390 uses diagnose instruction as hypercall (0x500) along with hypercall
number in R1.
+ For further information on the S390 diagnose call as supported by KVM,
+ refer to Documentation/virtual/kvm/s390-diag.txt.
+
PowerPC:
It uses R3-R10 and hypercall number in R11. R4-R11 are used as output registers.
Return value is placed in R3.
diff --git a/Documentation/virtual/kvm/s390-diag.txt b/Documentation/virtual/kvm/s390-diag.txt
new file mode 100644
index 0000000..f1de4fb
--- /dev/null
+++ b/Documentation/virtual/kvm/s390-diag.txt
@@ -0,0 +1,80 @@
+The s390 DIAGNOSE call on KVM
+=============================
+
+KVM on s390 supports the DIAGNOSE call for making hypercalls, both for
+native hypercalls and for selected hypercalls found on other s390
+hypervisors.
+
+Note that bits are numbered as by the usual s390 convention (most significant
+bit on the left).
+
+
+General remarks
+---------------
+
+DIAGNOSE calls by the guest cause a mandatory intercept. This implies
+all supported DIAGNOSE calls need to be handled by either KVM or its
+userspace.
+
+All DIAGNOSE calls supported by KVM use the RS-a format:
+
+--------------------------------------
+| '83' | R1 | R3 | B2 | D2 |
+--------------------------------------
+0 8 12 16 20 31
+
+The second-operand address (obtained by the base/displacement calculation)
+is not used to address data. Instead, bits 48-63 of this address specify
+the function code, and bits 0-47 are ignored.
+
+The supported DIAGNOSE function codes vary by the userspace used. For
+DIAGNOSE function codes not specific to KVM, please refer to the
+documentation for the s390 hypervisors defining them.
+
+
+DIAGNOSE function code 'X'500' - KVM virtio functions
+-----------------------------------------------------
+
+If the function code specifies 0x500, various virtio-related functions
+are performed.
+
+General register 1 contains the virtio subfunction code. Supported
+virtio subfunctions depend on KVM's userspace. Generally, userspace
+provides either s390-virtio (subcodes 0-2) or virtio-ccw (subcode 3).
+
+Upon completion of the DIAGNOSE instruction, general register 2 contains
+the function's return code, which is either a return code or a subcode
+specific value.
+
+Subcode 0 - s390-virtio notification and early console printk
+ Handled by userspace.
+
+Subcode 1 - s390-virtio reset
+ Handled by userspace.
+
+Subcode 2 - s390-virtio set status
+ Handled by userspace.
+
+Subcode 3 - virtio-ccw notification
+ Handled by either userspace or KVM (ioeventfd case).
+
+ General register 2 contains a subchannel-identification word denoting
+ the subchannel of the virtio-ccw proxy device to be notified.
+
+ General register 3 contains the number of the virtqueue to be notified.
+
+ General register 4 contains a 64bit identifier for KVM usage (the
+ kvm_io_bus cookie). If general register 4 does not contain a valid
+ identifier, it is ignored.
+
+ After completion of the DIAGNOSE call, general register 2 may contain
+ a 64bit identifier (in the kvm_io_bus cookie case).
+
+ See also the virtio standard for a discussion of this hypercall.
+
+
+DIAGNOSE function code 'X'501 - KVM breakpoint
+----------------------------------------------
+
+If the function code specifies 0x501, breakpoint functions may be performed.
+This function code is handled by userspace.
--
1.7.9.5
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PULL 2/6] KVM: s390: Use helper function to set CC in SIGP handler
2013-12-11 18:57 [PULL 0/6] KVM: s390: patches for kvm-next Cornelia Huck
2013-12-11 18:57 ` [PULL 1/6] KVM: s390: diagnose call documentation Cornelia Huck
@ 2013-12-11 18:57 ` Cornelia Huck
2013-12-11 18:57 ` [PULL 3/6] KVM: s390: Add the SIGP order CONDITIONAL EMERGENCY SIGNAL Cornelia Huck
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Cornelia Huck @ 2013-12-11 18:57 UTC (permalink / raw)
To: Gleb Natapov, Paolo Bonzini
Cc: Christian Borntraeger, kvm, linux-s390, Thomas Huth,
Cornelia Huck
From: Thomas Huth <thuth@linux.vnet.ibm.com>
We've got a helper function for setting the condition code now,
so let's use it in the SIGP handler, too.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
arch/s390/kvm/sigp.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index c370058..bc0d85a 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -435,7 +435,6 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
if (rc < 0)
return rc;
- vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
- vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
+ kvm_s390_set_psw_cc(vcpu, rc);
return 0;
}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PULL 3/6] KVM: s390: Add the SIGP order CONDITIONAL EMERGENCY SIGNAL
2013-12-11 18:57 [PULL 0/6] KVM: s390: patches for kvm-next Cornelia Huck
2013-12-11 18:57 ` [PULL 1/6] KVM: s390: diagnose call documentation Cornelia Huck
2013-12-11 18:57 ` [PULL 2/6] KVM: s390: Use helper function to set CC in SIGP handler Cornelia Huck
@ 2013-12-11 18:57 ` Cornelia Huck
2013-12-11 18:57 ` [PULL 4/6] KVM: s390: Reworked SIGP RESTART order Cornelia Huck
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Cornelia Huck @ 2013-12-11 18:57 UTC (permalink / raw)
To: Gleb Natapov, Paolo Bonzini
Cc: Christian Borntraeger, kvm, linux-s390, Thomas Huth,
Cornelia Huck
From: Thomas Huth <thuth@linux.vnet.ibm.com>
This patch adds the missing SIGP order "conditional emergency
signal" by calling the "emergency signal" SIGP handler if the
required conditions are met.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
arch/s390/include/asm/sigp.h | 1 +
arch/s390/kvm/sigp.c | 37 ++++++++++++++++++++++++++++++++++++-
2 files changed, 37 insertions(+), 1 deletion(-)
diff --git a/arch/s390/include/asm/sigp.h b/arch/s390/include/asm/sigp.h
index 5a87d16..c002cd5 100644
--- a/arch/s390/include/asm/sigp.h
+++ b/arch/s390/include/asm/sigp.h
@@ -12,6 +12,7 @@
#define SIGP_SET_PREFIX 13
#define SIGP_STORE_STATUS_AT_ADDRESS 14
#define SIGP_SET_ARCHITECTURE 18
+#define SIGP_COND_EMERGENCY_SIGNAL 19
#define SIGP_SENSE_RUNNING 21
/* SIGP condition codes */
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index bc0d85a..eee1402 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -1,7 +1,7 @@
/*
* handling interprocessor communication
*
- * Copyright IBM Corp. 2008, 2009
+ * Copyright IBM Corp. 2008, 2013
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2 only)
@@ -89,6 +89,37 @@ unlock:
return rc;
}
+static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr,
+ u16 asn, u64 *reg)
+{
+ struct kvm_vcpu *dst_vcpu = NULL;
+ const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT;
+ u16 p_asn, s_asn;
+ psw_t *psw;
+ u32 flags;
+
+ if (cpu_addr < KVM_MAX_VCPUS)
+ dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
+ if (!dst_vcpu)
+ return SIGP_CC_NOT_OPERATIONAL;
+ flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags);
+ psw = &dst_vcpu->arch.sie_block->gpsw;
+ p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */
+ s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */
+
+ /* Deliver the emergency signal? */
+ if (!(flags & CPUSTAT_STOPPED)
+ || (psw->mask & psw_int_mask) != psw_int_mask
+ || ((flags & CPUSTAT_WAIT) && psw->addr != 0)
+ || (!(flags & CPUSTAT_WAIT) && (asn == p_asn || asn == s_asn))) {
+ return __sigp_emergency(vcpu, cpu_addr);
+ } else {
+ *reg &= 0xffffffff00000000UL;
+ *reg |= SIGP_STATUS_INCORRECT_STATE;
+ return SIGP_CC_STATUS_STORED;
+ }
+}
+
static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
{
struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
@@ -417,6 +448,10 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
&vcpu->run->s.regs.gprs[r1]);
break;
+ case SIGP_COND_EMERGENCY_SIGNAL:
+ rc = __sigp_conditional_emergency(vcpu, cpu_addr, parameter,
+ &vcpu->run->s.regs.gprs[r1]);
+ break;
case SIGP_SENSE_RUNNING:
vcpu->stat.instruction_sigp_sense_running++;
rc = __sigp_sense_running(vcpu, cpu_addr,
--
1.7.9.5
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PULL 4/6] KVM: s390: Reworked SIGP RESTART order
2013-12-11 18:57 [PULL 0/6] KVM: s390: patches for kvm-next Cornelia Huck
` (2 preceding siblings ...)
2013-12-11 18:57 ` [PULL 3/6] KVM: s390: Add the SIGP order CONDITIONAL EMERGENCY SIGNAL Cornelia Huck
@ 2013-12-11 18:57 ` Cornelia Huck
2013-12-11 18:57 ` [PULL 5/6] KVM: s390: SIGP START has to report BUSY while stopping a CPU Cornelia Huck
2013-12-11 18:57 ` [PULL 6/6] KVM: s390: ioeventfd: ignore leftmost bits Cornelia Huck
5 siblings, 0 replies; 7+ messages in thread
From: Cornelia Huck @ 2013-12-11 18:57 UTC (permalink / raw)
To: Gleb Natapov, Paolo Bonzini
Cc: Christian Borntraeger, kvm, linux-s390, Thomas Huth,
Cornelia Huck
From: Thomas Huth <thuth@linux.vnet.ibm.com>
When SIGP RESTART detected an illegal CPU address, there is no need to
drop to userspace, we can return CC3 to the guest directly instead.
Also renamed __sigp_restart() to sigp_check_callable() (since this
is a better description of what the function is really doing) and
moved a string specific to RESTART to the calling place instead, so
that this function gets usable by other SIGP orders, too.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
arch/s390/kvm/sigp.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index eee1402..509547d 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -363,7 +363,8 @@ static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
return rc;
}
-static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
+/* Test whether the destination CPU is available and not busy */
+static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr)
{
struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
struct kvm_s390_local_interrupt *li;
@@ -382,9 +383,6 @@ static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
spin_lock_bh(&li->lock);
if (li->action_bits & ACTION_STOP_ON_STOP)
rc = SIGP_CC_BUSY;
- else
- VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
- cpu_addr);
spin_unlock_bh(&li->lock);
out:
spin_unlock(&fi->lock);
@@ -459,10 +457,15 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
break;
case SIGP_RESTART:
vcpu->stat.instruction_sigp_restart++;
- rc = __sigp_restart(vcpu, cpu_addr);
- if (rc == SIGP_CC_BUSY)
- break;
- /* user space must know about restart */
+ rc = sigp_check_callable(vcpu, cpu_addr);
+ if (rc == SIGP_CC_ORDER_CODE_ACCEPTED) {
+ VCPU_EVENT(vcpu, 4,
+ "sigp restart %x to handle userspace",
+ cpu_addr);
+ /* user space must know about restart */
+ rc = -EOPNOTSUPP;
+ }
+ break;
default:
return -EOPNOTSUPP;
}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PULL 5/6] KVM: s390: SIGP START has to report BUSY while stopping a CPU
2013-12-11 18:57 [PULL 0/6] KVM: s390: patches for kvm-next Cornelia Huck
` (3 preceding siblings ...)
2013-12-11 18:57 ` [PULL 4/6] KVM: s390: Reworked SIGP RESTART order Cornelia Huck
@ 2013-12-11 18:57 ` Cornelia Huck
2013-12-11 18:57 ` [PULL 6/6] KVM: s390: ioeventfd: ignore leftmost bits Cornelia Huck
5 siblings, 0 replies; 7+ messages in thread
From: Cornelia Huck @ 2013-12-11 18:57 UTC (permalink / raw)
To: Gleb Natapov, Paolo Bonzini
Cc: Christian Borntraeger, kvm, linux-s390, Thomas Huth,
Cornelia Huck
From: Thomas Huth <thuth@linux.vnet.ibm.com>
Just like the RESTART order, the START order also has to report BUSY
while a STOP request is pending, to avoid that the START might be
ignored due to a race condition between the STOP and the START order.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
arch/s390/include/asm/sigp.h | 1 +
arch/s390/kvm/sigp.c | 5 +++++
2 files changed, 6 insertions(+)
diff --git a/arch/s390/include/asm/sigp.h b/arch/s390/include/asm/sigp.h
index c002cd5..d091aa1 100644
--- a/arch/s390/include/asm/sigp.h
+++ b/arch/s390/include/asm/sigp.h
@@ -5,6 +5,7 @@
#define SIGP_SENSE 1
#define SIGP_EXTERNAL_CALL 2
#define SIGP_EMERGENCY_SIGNAL 3
+#define SIGP_START 4
#define SIGP_STOP 5
#define SIGP_RESTART 6
#define SIGP_STOP_AND_STORE_STATUS 9
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index 509547d..87c2b3a 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -455,6 +455,11 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
rc = __sigp_sense_running(vcpu, cpu_addr,
&vcpu->run->s.regs.gprs[r1]);
break;
+ case SIGP_START:
+ rc = sigp_check_callable(vcpu, cpu_addr);
+ if (rc == SIGP_CC_ORDER_CODE_ACCEPTED)
+ rc = -EOPNOTSUPP; /* Handle START in user space */
+ break;
case SIGP_RESTART:
vcpu->stat.instruction_sigp_restart++;
rc = sigp_check_callable(vcpu, cpu_addr);
--
1.7.9.5
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PULL 6/6] KVM: s390: ioeventfd: ignore leftmost bits
2013-12-11 18:57 [PULL 0/6] KVM: s390: patches for kvm-next Cornelia Huck
` (4 preceding siblings ...)
2013-12-11 18:57 ` [PULL 5/6] KVM: s390: SIGP START has to report BUSY while stopping a CPU Cornelia Huck
@ 2013-12-11 18:57 ` Cornelia Huck
5 siblings, 0 replies; 7+ messages in thread
From: Cornelia Huck @ 2013-12-11 18:57 UTC (permalink / raw)
To: Gleb Natapov, Paolo Bonzini
Cc: Christian Borntraeger, kvm, linux-s390, Dominik Dingel, stable,
Cornelia Huck
From: Dominik Dingel <dingel@linux.vnet.ibm.com>
The diagnose 500 subcode 3 contains the 32 bit subchannel id in bits 32-63
(counting from the left). As for other I/O instructions, bits 0-31 should be
ignored and thus not be passed to kvm_io_bus_write_cookie().
This fixes a bug where the guest passed non-zero bits 0-31 which the
host tried to interpret, leading to ioeventfd notification failures.
Cc: stable@vger.kernel.org
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
arch/s390/kvm/diag.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 5ff29be..8216c0e 100644
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -121,7 +121,7 @@ static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
* - gpr 4 contains the index on the bus (optionally)
*/
ret = kvm_io_bus_write_cookie(vcpu->kvm, KVM_VIRTIO_CCW_NOTIFY_BUS,
- vcpu->run->s.regs.gprs[2],
+ vcpu->run->s.regs.gprs[2] & 0xffffffff,
8, &vcpu->run->s.regs.gprs[3],
vcpu->run->s.regs.gprs[4]);
--
1.7.9.5
^ permalink raw reply related [flat|nested] 7+ messages in thread