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2016-06-14MIPS: KVM: Drop unused guest_inst from kvm_vcpu_archJames Hogan
The MIPS kvm_vcpu_arch::guest_inst isn't used, so drop it from the struct and drop its asm-offsets definition. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14Merge branch 'kvm-mips-fixes' into HEADPaolo Bonzini
Merge MIPS patches destined to both 4.7 and kvm/next, to avoid unnecessary conflicts. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14MIPS: KVM: Fix CACHE triggered exception emulationJames Hogan
When emulating TLB miss / invalid exceptions during CACHE instruction emulation, be sure to set up the correct PC and host_cp0_badvaddr state for the kvm_mips_emlulate_tlb*_ld() function to pick up for guest EPC and BadVAddr. PC needs to be rewound otherwise the guest EPC will end up pointing at the next instruction after the faulting CACHE instruction. host_cp0_badvaddr must be set because guest CACHE instructions trap with a Coprocessor Unusable exception, which doesn't update the host BadVAddr as a TLB exception would. This doesn't tend to get hit when dynamic translation of emulated instructions is enabled, since only the first execution of each CACHE instruction actually goes through this code path, with subsequent executions hitting the SYNCI instruction that it gets replaced with. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14MIPS: KVM: Don't unwind PC when emulating CACHEJames Hogan
When a CACHE instruction is emulated by kvm_mips_emulate_cache(), the PC is first updated to point to the next instruction, and afterwards it falls through the "dont_update_pc" label, which rewinds the PC back to its original address. This works when dynamic translation of emulated instructions is enabled, since the CACHE instruction is replaced with a SYNCI which works without trapping, however when dynamic translation is disabled the guest hangs on CACHE instructions as they always trap and are never stepped over. Roughly swap the meanings of the "done" and "dont_update_pc" to match kvm_mips_emulate_CP0(), so that "done" will roll back the PC on failure, and "dont_update_pc" won't change PC at all (for the sake of exceptions that have already modified the PC). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14MIPS: KVM: Include bit 31 in segment matchesJames Hogan
When faulting guest addresses are matched against guest segments with the KVM_GUEST_KSEGX() macro, change the mask to 0xe0000000 so as to include bit 31. This is mainly for safety's sake, as it prevents a rogue BadVAddr in the host kseg2/kseg3 segments (e.g. 0xC*******) after a TLB exception from matching the guest kseg0 segment (e.g. 0x4*******), triggering an internal KVM error instead of allowing the corresponding guest kseg0 page to be mapped into the host vmalloc space. Such a rogue BadVAddr was observed to happen with the host MIPS kernel running under QEMU with KVM built as a module, due to a not entirely transparent optimisation in the QEMU TLB handling. This has already been worked around properly in a previous commit. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14MIPS: KVM: Fix modular KVM under QEMUJames Hogan
Copy __kvm_mips_vcpu_run() into unmapped memory, so that we can never get a TLB refill exception in it when KVM is built as a module. This was observed to happen with the host MIPS kernel running under QEMU, due to a not entirely transparent optimisation in the QEMU TLB handling where TLB entries replaced with TLBWR are copied to a separate part of the TLB array. Code in those pages continue to be executable, but those mappings persist only until the next ASID switch, even if they are marked global. An ASID switch happens in __kvm_mips_vcpu_run() at exception level after switching to the guest exception base. Subsequent TLB mapped kernel instructions just prior to switching to the guest trigger a TLB refill exception, which enters the guest exception handlers without updating EPC. This appears as a guest triggered TLB refill on a host kernel mapped (host KSeg2) address, which is not handled correctly as user (guest) mode accesses to kernel (host) segments always generate address error exceptions. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 3.10.x- Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-10KVM: s390: handle missing storage-key facilityDavid Hildenbrand
Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: trace and count all skey interceptsDavid Hildenbrand
Let's trace and count all skey handling operations, even if lazy skey handling was already activated. Also, don't enable lazy skey handling if anything went wrong while enabling skey handling for the SIE. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect storage-key facilityDavid Hildenbrand
Let's correctly detect that facility. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: pfmf: handle address overflowsDavid Hildenbrand
In theory, end could always end up being < start, if overflowing to 0. Although very unlikely for now, let's just fix it. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: pfmf: support conditional-sske facilityDavid Hildenbrand
We already indicate that facility but don't implement it in our pfmf interception handler. Let's add a new storage key handling function for conditionally setting the guest storage key. As we will reuse this function later on, let's directly implement returning the old key via parameter and indicating if any change happened via rc. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: pfmf: take care of amode when setting reg2David Hildenbrand
Depending on the addressing mode, we must not overwrite bit 0-31 of the register. In addition, 24 bit and 31 bit have to set certain bits to 0, which is guaranteed by converting the end address to an effective address. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: pfmf: MR and MC are ignored without CSSKEDavid Hildenbrand
These two bits are simply ignored when the conditional-SSKE facility is not installed. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: pfmf: fix end address calculationDavid Hildenbrand
The current calculation is wrong if absolute != real address. Let's just calculate the start address for 4k frames upfront. Otherwise, the calculated end address will be wrong, resulting in wrong memory location/storage keys getting touched. To keep low-address protection working (using the effective address), we have to move the check. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: storage keys fit into a charDavid Hildenbrand
No need to convert the storage key into an unsigned long, the target function expects a char as argument. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/mm: return key via pointer in get_guest_storage_keyDavid Hildenbrand
Let's just split returning the key and reporting errors. This makes calling code easier and avoids bugs as happened already. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/mm: simplify get_guest_storage_keyDavid Hildenbrand
We can safe a few LOC and make that function easier to understand by rewriting existing code. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/mm: set and get guest storage key mmap lockingMartin Schwidefsky
Move the mmap semaphore locking out of set_guest_storage_key and get_guest_storage_key. This makes the two functions more like the other ptep_xxx operations and allows to avoid repeated semaphore operations if multiple keys are read or written. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/mm: don't drop errors in get_guest_storage_keyDavid Hildenbrand
Commit 1e133ab296f3 ("s390/mm: split arch/s390/mm/pgtable.c") changed the return value of get_guest_storage_key to an unsigned char, resulting in -EFAULT getting interpreted as a valid storage key. Cc: stable@vger.kernel.org # 4.6+ Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: fixup I/O interrupt tracesChristian Borntraeger
We currently have two issues with the I/O interrupt injection logging: 1. All QEMU versions up to 2.6 have a wrong encoding of device numbers etc for the I/O interrupt type, so the inject VM_EVENT will have wrong data. Let's fix this by using the interrupt parameters and not the interrupt type number. 2. We only log in kvm_s390_inject_vm, but not when coming from kvm_s390_reinject_io_int or from flic. Let's move the logging to the common __inject_io function. We also enhance the logging for delivery to match the data. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-06-10KVM: s390: provide logging for diagnose 0x500Christian Borntraeger
We might need to debug some virtio things, so better have diagnose 500 logged. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-06-10KVM: s390: turn on tx even without ctxDavid Hildenbrand
Constrained transactional execution is an addon of transactional execution. Let's enable the assist also if only TX is enabled for the guest. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: enable host-protection-interruption only with ESOPDavid Hildenbrand
host-protection-interruption control was introduced with ESOP. So let's enable it only if we have ESOP and add an explanatory comment why we can live without it. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: enable ibs only if availableDavid Hildenbrand
Let's enable interlock-and-broadcast suppression only if the facility is actually available. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect interlock-and-broadcast-suppression facilityDavid Hildenbrand
Let's detect that facility. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: enable PFMFI only if availableDavid Hildenbrand
Let's enable interpretation of PFMFI only if the facility is actually available. Emulation code still works in case the guest is offered EDAT-1. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect PFMF interpretation facilityDavid Hildenbrand
Let's detect that facility. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: enable cei only if availableDavid Hildenbrand
Let's only enable conditional-external-interruption if the facility is actually available. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect conditional-external-interception facilityDavid Hildenbrand
Let's detect if we have that facility. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: enable ib only if availableDavid Hildenbrand
Let's enable intervention bypass only if the facility is acutally available. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect intervention bypass facilityDavid Hildenbrand
Let's detect if we have the intervention bypass facility installed. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: handle missing guest-storage-limit-suppressionDavid Hildenbrand
If guest-storage-limit-suppression is not available, we would for now have a valid guest address space with size 0. So let's simply set the origin to 0 and the limit to hamax. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect guest-storage-limit-suppressionDavid Hildenbrand
Let's detect that facility. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: provide CMMA attributes only if availableDavid Hildenbrand
Let's not provide the device attribute for cmma enabling and clearing if the hardware doesn't support it. This also helps getting rid of the undocumented return value "-EINVAL" in case CMMA is not available when trying to enable it. Also properly document the meaning of -EINVAL for CMMA clearing. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: enable CMMA if the interpration is availableDavid Hildenbrand
Now that we can detect if collaborative-memory-management interpretation is available, replace the heuristic by a real hardware detection. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect cmmaDavid Hildenbrand
Let's detect the Collaborative-memory-management-interpretation facility, aka CMM assist, so we can correctly enable cmma later. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: guestdbg: signal missing hardware supportDavid Hildenbrand
Without guest-PER enhancement, we can't provide any debugging support. Therefore act like kernel support is missing. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect guest-PER enhancementDavid Hildenbrand
Let's detect that facility, so we can correctly handle its abscence. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: handle missing 64-bit-SCAO facilityDavid Hildenbrand
Without that facility, we may only use scaol. So fallback to DMA allocation in that case, so we won't overwrite random memory via the SIE. Also disallow ESCA, so we don't have to handle that allocation case. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/sclp: detect 64-bit-SCAO facilityDavid Hildenbrand
Let's correctly detect that facility, so we can correctly handle its abscence later on. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: interface to query and configure cpu subfunctionsDavid Hildenbrand
We have certain instructions that indicate available subfunctions via a query subfunction (crypto functions and ptff), or via a test bit function (plo). By exposing these "subfunction blocks" to user space, we allow user space to 1) query available subfunctions and make sure subfunctions won't get lost during migration - e.g. properly indicate them via a CPU model 2) change the subfunctions to be reported to the guest (even adding unavailable ones) This mechanism works just like the way we indicate the stfl(e) list to user space. This way, user space could even emulate some subfunctions in QEMU in the future. If this is ever applicable, we have to make sure later on, that unsupported subfunctions result in an intercept to QEMU. Please note that support to indicate them to the guest is still missing and requires hardware support. Usually, the IBC takes already care of these subfunctions for migration safety. QEMU should make sure to always set these bits properly according to the machine generation to be emulated. Available subfunctions are only valid in combination with STFLE bits retrieved via KVM_S390_VM_CPU_MACHINE and enabled via KVM_S390_VM_CPU_PROCESSOR. If the applicable bits are available, the indicated subfunctions are guaranteed to be correct. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10s390/crypto: allow to query all known cpacf functionsDavid Hildenbrand
KVM will have to query these functions, let's add at least the query capabilities. PCKMO has RRE format, as bit 16-31 are ignored, we can still use the existing function. As PCKMO won't touch the cc, let's force it to 0 upfront. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Acked-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: gaccess: convert get_vcpu_asce()David Hildenbrand
Let's use our new function for preparing translation exceptions. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: gaccess: convert guest_page_range()David Hildenbrand
Let's use our new function for preparing translation exceptions. As we will need the correct ar, let's pass that to guest_page_range(). This will also make sure that the guest address is stored in the tec for applicable excptions. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: gaccess: convert guest_translate_address()David Hildenbrand
Let's use our new function for preparing translation exceptions. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: gaccess: convert kvm_s390_check_low_addr_prot_real()David Hildenbrand
Let's use our new function for preparing translation exceptions. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: gaccess: function for preparing translation exceptionsDavid Hildenbrand
Let's provide a function trans_exc() that can be used for handling preparation of translation exceptions on a central basis. We will use that function to replace existing code in gaccess. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: gaccess: store guest address on ALC prot exceptionsDavid Hildenbrand
Let's pass the effective guest address to get_vcpu_asce(), so we can properly set the guest address in case we inject an ALC protection exception. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: forward ESOP if availableDavid Hildenbrand
ESOP guarantees that during a protection exception, bit 61 of real location 168-175 will only be set to 1 if it was because of ALCP or DATP. If the exception is due to LAP or KCP, the bit will always be set to 0. The old SOP definition allowed bit 61 to be unpredictable in case of LAP or KCP in some conditions. So ESOP replaces this unpredictability by a guarantee. Therefore, we can directly forward ESOP if it is available on our machine. We don't have to do anything when ESOP is disabled - the guest will simply expect unpredictable values. Our guest access functions are already handling ESOP properly. Please note that future functionality in KVM will require knowledge about ESOP being enabled for a guest or not. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10KVM: s390: interface to query and configure cpu featuresDavid Hildenbrand
For now, we only have an interface to query and configure facilities indicated via STFL(E). However, we also have features indicated via SCLP, that have to be indicated to the guest by user space and usually require KVM support. This patch allows user space to query and configure available cpu features for the guest. Please note that disabling a feature doesn't necessarily mean that it is completely disabled (e.g. ESOP is mostly handled by the SIE). We will try our best to disable it. Most features (e.g. SCLP) can't directly be forwarded, as most of them need in addition to hardware support, support in KVM. As we later on want to turn these features in KVM explicitly on/off (to simulate different behavior), we have to filter all features provided by the hardware and make them configurable. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>