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2012-07-10powerpc: Move and fix MTMSR_EERI definitionBenjamin Herrenschmidt
Move this duplicated definition to ppc_asm.h and remove the braces which prevent the use of %rN register names Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-05-24Merge branch 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM changes from Avi Kivity: "Changes include additional instruction emulation, page-crossing MMIO, faster dirty logging, preventing the watchdog from killing a stopped guest, module autoload, a new MSI ABI, and some minor optimizations and fixes. Outside x86 we have a small s390 and a very large ppc update. Regarding the new (for kvm) rebaseless workflow, some of the patches that were merged before we switch trees had to be rebased, while others are true pulls. In either case the signoffs should be correct now." Fix up trivial conflicts in Documentation/feature-removal-schedule.txt arch/powerpc/kvm/book3s_segment.S and arch/x86/include/asm/kvm_para.h. I suspect the kvm_para.h resolution ends up doing the "do I have cpuid" check effectively twice (it was done differently in two different commits), but better safe than sorry ;) * 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (125 commits) KVM: make asm-generic/kvm_para.h have an ifdef __KERNEL__ block KVM: s390: onereg for timer related registers KVM: s390: epoch difference and TOD programmable field KVM: s390: KVM_GET/SET_ONEREG for s390 KVM: s390: add capability indicating COW support KVM: Fix mmu_reload() clash with nested vmx event injection KVM: MMU: Don't use RCU for lockless shadow walking KVM: VMX: Optimize %ds, %es reload KVM: VMX: Fix %ds/%es clobber KVM: x86 emulator: convert bsf/bsr instructions to emulate_2op_SrcV_nobyte() KVM: VMX: unlike vmcs on fail path KVM: PPC: Emulator: clean up SPR reads and writes KVM: PPC: Emulator: clean up instruction parsing kvm/powerpc: Add new ioctl to retreive server MMU infos kvm/book3s: Make kernel emulated H_PUT_TCE available for "PR" KVM KVM: PPC: bookehv: Fix r8/r13 storing in level exception handler KVM: PPC: Book3S: Enable IRQs during exit handling KVM: PPC: Fix PR KVM on POWER7 bare metal KVM: PPC: Fix stbux emulation KVM: PPC: bookehv: Use lwz/stw instead of PPC_LL/PPC_STL for 32-bit fields ...
2012-05-16KVM: PPC: Book3S: PR: Fix hsrr codeAlexander Graf
When jumping back into the kernel to code that knows that it would be using HSRR registers instead of SRR registers, we need to make sure we pass it all information on where to jump to in HSRR registers. Unfortunately, we used r10 to store the information to distinguish between the HSRR and SRR case. That register got clobbered in between though, rendering the later comparison invalid. Instead, let's use cr1 to store this information. That way we don't need yet another register and everyone's happy. This fixes PR KVM on POWER7 bare metal for me. Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-16KVM: PPC: Fix PR KVM on POWER7 bare metalAlexander Graf
When running on a system that is HV capable, some interrupts use HSRR SPRs instead of the normal SRR SPRs. These are also used in the Linux handlers to jump back to code after an interrupt got processed. Unfortunately, in our "jump back to the real host handler after we've done the context switch" code, we were only setting the SRR SPRs, rendering Linux to jump back to some invalid IP after it's processed the interrupt. This fixes random crashes on p7 opal mode with PR KVM for me. Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-16KVM: PPC: Book3S: PR: Handle EMUL_ASSISTAlexander Graf
In addition to normal "priviledged instruction" traps, we can also receive "emulation assist" traps on newer hardware that has the HV bit set. Handle that one the same way as a privileged instruction, including the instruction fetching. That way we don't execute old instructions that we happen to still leave in that field when an emul assist trap comes. This fixes -M mac99 / -M g3beige on p7 bare metal for me. Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-06KVM: PPC: Fix PR KVM on POWER7 bare metalAlexander Graf
When running on a system that is HV capable, some interrupts use HSRR SPRs instead of the normal SRR SPRs. These are also used in the Linux handlers to jump back to code after an interrupt got processed. Unfortunately, in our "jump back to the real host handler after we've done the context switch" code, we were only setting the SRR SPRs, rendering Linux to jump back to some invalid IP after it's processed the interrupt. This fixes random crashes on p7 opal mode with PR KVM for me. Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-06KVM: PPC: Book3S: PR: Optimize entry pathAlexander Graf
By shuffling a few instructions around we can execute more memory loads in parallel, giving us a small performance boost. With this patch and a simple priviledged SPR access loop guest, I get a speed bump from 2013052 to 2035607 exits per second. Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25KVM: PPC: book3s_pr: Simplify transitions between virtual and real modePaul Mackerras
This simplifies the way that the book3s_pr makes the transition to real mode when entering the guest. We now call kvmppc_entry_trampoline (renamed from kvmppc_rmcall) in the base kernel using a normal function call instead of doing an indirect call through a pointer in the vcpu. If kvm is a module, the module loader takes care of generating a trampoline as it does for other calls to functions outside the module. kvmppc_entry_trampoline then disables interrupts and jumps to kvmppc_handler_trampoline_enter in real mode using an rfi[d]. That then uses the link register as the address to return to (potentially in module space) when the guest exits. This also simplifies the way that we call the Linux interrupt handler when we exit the guest due to an external, decrementer or performance monitor interrupt. Instead of turning on the MMU, then deciding that we need to call the Linux handler and turning the MMU back off again, we now go straight to the handler at the point where we would turn the MMU on. The handler will then return to the virtual-mode code (potentially in the module). Along the way, this moves the setting and clearing of the HID5 DCBZ32 bit into real-mode interrupts-off code, and also makes sure that we clear the MSR[RI] bit before loading values into SRR0/1. The net result is that we no longer need any code addresses to be stored in vcpu->arch. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25KVM: PPC: Read out syscall instruction on trapAlexander Graf
We have a few traps where we cache the instruction that cause the trap for analysis later on. Since we now need to be able to distinguish between SC 0 and SC 1 system calls and the only way to find out which is which is by looking at the instruction, we also read out the instruction causing the system call. Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12powerpc, KVM: Split HVMODE_206 cpu feature bit into separate HV and ↵Paul Mackerras
architecture bits This replaces the single CPU_FTR_HVMODE_206 bit with two bits, one to indicate that we have a usable hypervisor mode, and another to indicate that the processor conforms to PowerISA version 2.06. We also add another bit to indicate that the processor conforms to ISA version 2.01 and set that for PPC970 and derivatives. Some PPC970 chips (specifically those in Apple machines) have a hypervisor mode in that MSR[HV] is always 1, but the hypervisor mode is not useful in the sense that there is no way to run any code in supervisor mode (HV=0 PR=0). On these processors, the LPES0 and LPES1 bits in HID4 are always 0, and we use that as a way of detecting that hypervisor mode is not useful. Where we have a feature section in assembly code around code that only applies on POWER7 in hypervisor mode, we use a construct like END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206) The definition of END_FTR_SECTION_IFSET is such that the code will be enabled (not overwritten with nops) only if all bits in the provided mask are set. Note that the CPU feature check in __tlbie() only needs to check the ARCH_206 bit, not the HVMODE bit, because __tlbie() can only get called if we are running bare-metal, i.e. in hypervisor mode. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12KVM: PPC: Add support for Book3S processors in hypervisor modePaul Mackerras
This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12KVM: PPC: Split host-state fields out of kvmppc_book3s_shadow_vcpuPaul Mackerras
There are several fields in struct kvmppc_book3s_shadow_vcpu that temporarily store bits of host state while a guest is running, rather than anything relating to the particular guest or vcpu. This splits them out into a new kvmppc_host_state structure and modifies the definitions in asm-offsets.c to suit. On 32-bit, we have a kvmppc_host_state structure inside the kvmppc_book3s_shadow_vcpu since the assembly code needs to be able to get to them both with one pointer. On 64-bit they are separate fields in the PACA. This means that on 64-bit we don't need to copy the kvmppc_host_state in and out on vcpu load/unload, and in future will mean that the book3s_hv code doesn't need a shadow_vcpu struct in the PACA at all. That does mean that we have to be careful not to rely on any values persisting in the hstate field of the paca across any point where we could block or get preempted. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12powerpc, KVM: Rework KVM checks in first-level interrupt handlersPaul Mackerras
Instead of branching out-of-line with the DO_KVM macro to check if we are in a KVM guest at the time of an interrupt, this moves the KVM check inline in the first-level interrupt handlers. This speeds up the non-KVM case and makes sure that none of the interrupt handlers are missing the check. Because the first-level interrupt handlers are now larger, some things had to be move out of line in exceptions-64s.S. This all necessitated some minor changes to the interrupt entry code in KVM. This also streamlines the book3s_32 KVM test. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-04-20powerpc: Always use SPRN_SPRG_HSCRATCH0 when running in HV modePaul Mackerras
This uses feature sections to arrange that we always use HSPRG1 as the scratch register in the interrupt entry code rather than SPRG2 when we're running in hypervisor mode on POWER7. This will ensure that we don't trash the guest's SPRG2 when we are running KVM guests. To simplify the code, we define GET_SCRATCH0() and SET_SCRATCH0() macros like the GET_PACA/SET_PACA macros. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-20powerpc: Base support for exceptions using HSRR0/1Benjamin Herrenschmidt
Pass the register type to the prolog, also provides alternate "HV" version of hardware interrupt (0x500) and adjust LPES accordingly We tag those interrupts by setting bit 0x2 in the trap number Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-17KVM: PPC: Make Alignment interrupts work againAlexander Graf
In the process of merging Book3S_32 and 64 I somehow ended up having the alignment interrupt handler take last_inst, but the fetching code not fetching it. So we ended up with stale last_inst values. Let's just enable last_inst fetching for alignment interrupts too. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17KVM: PPC: Add generic segment switching codeAlexander Graf
This is the code that will later be used instead of book3s_64_slb.S. It does the last step of guest entry and the first generic steps of guest exiting, once we have determined the interrupt is a KVM interrupt. It also reads the last used instruction from the guest virtual address space if necessary, to speed up that path. The new thing about this file is that it makes use of generic long load and store functions and calls a macro to fill in the actual segment switching code. That still needs to be done differently for book3s_32 and book3s_64. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>