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2018-06-03powerpc/time: account broadcast timer event interrupts separatelyNicholas Piggin3-4/+8
These are not local timer interrupts but IPIs. It's good to be able to see how timer offloading is behaving, so split these out into their own category. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc: move a stray NMI IPI case under NMI_IPI ifdefNicholas Piggin1-0/+2
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc: move timer broadcast code under GENERIC_CLOCKEVENTS_BROADCAST ifdefNicholas Piggin2-0/+10
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc: allow soft-NMI watchdog to cover timer interrupts with large decrementersNicholas Piggin1-6/+13
Large decrementers (e.g., POWER9) can take a very long time to wrap, so when the timer iterrupt handler sets the decrementer to max so as to avoid taking another decrementer interrupt when hard enabling interrupts before running timers, it effectively disables the soft NMI coverage for timer interrupts. Fix this by using the traditional 31-bit value instead, which wraps after a few seconds. masked interrupt code does the same thing, and in normal operation neither of these paths would ever wrap even the 31 bit value. Note: the SMP watchdog should catch timer interrupt lockups, but it is preferable for the local soft-NMI to catch them, mainly to avoid the IPI. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc: generic clockevents broadcast receiver call tick_receive_broadcastNicholas Piggin4-48/+42
The broadcast tick recipient can call tick_receive_broadcast rather than re-running the full timer interrupt. It does not have to check for the next event time, because the sender already determined the timer has expired. It does not have to test irq_work_pending, because that's a direct decrementer interrupt and does not go through the clock events subsystem. And it does not have to read PURR because that was removed with the previous patch. This results in no code size change, but both the decrementer and broadcast path lengths are reduced. Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/pseries: lparcfg calculate PURR on demandNicholas Piggin4-38/+10
For SPLPAR, lparcfg provides a sum of PURR registers for all CPUs. Currently this is done by reading PURR in context switch and timer interrupt, and storing that into a per-CPU variable. These are summed to provide the value. This does not work with all timer schemes (e.g., NO_HZ_FULL), and it is sub-optimal for performance because it reads the PURR register on every context switch, although that's been difficult to distinguish from noise in the contxt_switch microbenchmark. This patch implements the sum by calling a function on each CPU, to read and add PURR values of each CPU. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64: remove start_tb and accum_tb from thread_structNicholas Piggin2-9/+1
These fields are only written to. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64s: micro-optimise __hard_irq_enable() for mtmsrd L=1 supportNicholas Piggin1-2/+2
Book3S minimum supported ISA version now requires mtmsrd L=1. This instruction does not require bits other than RI and EE to be supplied, so __hard_irq_enable() and __hard_irq_disable() does not have to read the kernel_msr from paca. Interrupt entry code already relies on L=1 support. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/pseries: put cede MSR[EE] check under IRQ_SOFT_MASK_DEBUGNicholas Piggin1-4/+4
This check does not catch IRQ soft mask bugs, but this option is slightly more suitable than TRACE_IRQFLAGS. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64: irq_work avoid interrupt when called with hardware irqs enabledNicholas Piggin1-2/+31
irq_work_raise should not cause a decrementer exception unless it is called from NMI context. Doing so often just results in an immediate masked decrementer interrupt: <...>-550 90d... 4us : update_curr_rt <-dequeue_task_rt <...>-550 90d... 5us : dbs_update_util_handler <-update_curr_rt <...>-550 90d... 6us : arch_irq_work_raise <-irq_work_queue <...>-550 90d... 7us : soft_nmi_interrupt <-soft_nmi_common <...>-550 90d... 7us : printk_nmi_enter <-soft_nmi_interrupt <...>-550 90d.Z. 8us : rcu_nmi_enter <-soft_nmi_interrupt <...>-550 90d.Z. 9us : rcu_nmi_exit <-soft_nmi_interrupt <...>-550 90d... 9us : printk_nmi_exit <-soft_nmi_interrupt <...>-550 90d... 10us : cpuacct_charge <-update_curr_rt The soft_nmi_interrupt here is the call into the watchdog, due to the decrementer interrupt firing with irqs soft-disabled. This is harmless, but sub-optimal. When it's not called from NMI context or with interrupts enabled, mark the decrementer pending in the irq_happened mask directly, rather than having the masked decrementer interupt handler do it. This will be replayed at the next local_irq_enable. See the comment for details. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/powernv/ioda2: Remove redundant free of TCE pagesAlexey Kardashevskiy1-1/+0
When IODA2 creates a PE, it creates an IOMMU table with it_ops::free set to pnv_ioda2_table_free() which calls pnv_pci_ioda2_table_free_pages(). Since iommu_tce_table_put() calls it_ops::free when the last reference to the table is released, explicit call to pnv_pci_ioda2_table_free_pages() is not needed so let's remove it. This should fix double free in the case of PCI hotuplug as pnv_pci_ioda2_table_free_pages() does not reset neither iommu_table::it_base nor ::it_size. This was not exposed by SRIOV as it uses different code path via pnv_pcibios_sriov_disable(). IODA1 does not inialize it_ops::free so it does not have this issue. Fixes: c5f7700bbd2e ("powerpc/powernv: Dynamically release PE") Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/xmon: use match_string() helperYisheng Xie1-12/+11
match_string() returns the index of an array for a matching string, which can be used instead of open coded variant. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc: Fix build by disabling attribute-alias warning for SYSCALL_DEFINExChristophe Leroy6-0/+28
GCC 8.1 emits warnings such as the following. As arch/powerpc code is built with -Werror, this breaks the build with GCC 8.1. In file included from arch/powerpc/kernel/pci_64.c:23: ./include/linux/syscalls.h:233:18: error: 'sys_pciconfig_iobase' alias between functions of incompatible types 'long int(long int, long unsigned int, long unsigned int)' and 'long int(long int, long int, long int)' [-Werror=attribute-alias] asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \ ^~~ ./include/linux/syscalls.h:222:2: note: in expansion of macro '__SYSCALL_DEFINEx' __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) This patch inhibits those warnings. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Trim change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64: Fix strncpy() related build failures with GCC 8.1Christophe Leroy2-4/+4
GCC 8.1 warns about possible string truncation: arch/powerpc/kernel/nvram_64.c:1042:2: error: 'strncpy' specified bound 12 equals destination size [-Werror=stringop-truncation] strncpy(new_part->header.name, name, 12); arch/powerpc/platforms/ps3/repository.c:106:2: error: 'strncpy' output truncated before terminating nul copying 8 bytes from a string of the same length [-Werror=stringop-truncation] strncpy((char *)&n, text, 8); Fix it by using memcpy(). To make that safe we need to ensure the destination is pre-zeroed. Use kzalloc() in the nvram code and initialise the u64 to zero in the ps3 code. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Use kzalloc() in the nvram code, flesh out change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03Merge branch 'topic/pkey' into nextMichael Ellerman2-18/+0
This is a branch with a mixture of mm, x86 and powerpc commits all relating to some minor cross-arch pkeys consolidation. The x86/mm changes have been reviewed by Ingo & Dave Hansen and the tree has been in linux-next for some weeks without issue.
2018-06-03Merge branch 'fixes' into nextMichael Ellerman6-20/+48
We ended up with an ugly conflict between fixes and next in ftrace.h involving multiple nested ifdefs, and the automatic resolution is wrong. So merge fixes into next so we can fix it up.
2018-06-03Merge branch 'topic/kbuild' into nextMichael Ellerman4-27/+47
Merge in some commits we're sharing with the kbuild tree.
2018-06-03Merge branch 'topic/ppc-kvm' into nextMichael Ellerman10-12/+260
Merge in some commits we're sharing with the kvm-ppc tree.
2018-06-01kvm: no need to check return value of debugfs_create functionsGreg Kroah-Hartman1-2/+1
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. This cleans up the error handling a lot, as this code will never get hit. Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Christoffer Dall <christoffer.dall@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim KrÄmář" <rkrcmar@redhat.com> Cc: Arvind Yadav <arvind.yadav.cs@gmail.com> Cc: Eric Auger <eric.auger@redhat.com> Cc: Andre Przywara <andre.przywara@arm.com> Cc: kvm-ppc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01kvm: Change return type to vm_fault_tSouptick Joarder1-1/+1
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. commit 1c8f422059ae ("mm: change return type to vm_fault_t") Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-02powerpc/mm: Fix kernel crash on page table freeAneesh Kumar K.V3-1/+3
Fix the below crash on Book3E 64. pgtable_page_dtor expects struct page *arg. Also call the destructor on non book3s platforms correctly. This frees up the split PTL locks correctly if we had allocated them before. Call Trace: .kmem_cache_free+0x9c/0x44c (unreliable) .ptlock_free+0x1c/0x30 .tlb_remove_table+0xdc/0x224 .free_pgd_range+0x298/0x500 .shift_arg_pages+0x10c/0x1e0 .setup_arg_pages+0x200/0x25c .load_elf_binary+0x450/0x16c8 .search_binary_handler.part.11+0x9c/0x248 .do_execveat_common.isra.13+0x868/0xc18 .run_init_process+0x34/0x4c .try_to_run_init_process+0x1c/0x68 .kernel_init+0xdc/0x130 .ret_from_kernel_thread+0x58/0x7c Fixes: 702346768 ("powerpc/mm/nohash: Remove pte fragment dependency from nohash") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-02powerpc/prom: Fix %u/%llx usage since prom_printf() changeMathieu Malaterre1-24/+49
In commit eae5f709a4d7 ("powerpc: Add __printf verification to prom_printf") __printf attribute was added to prom_printf(), which means GCC started warning about type/format mismatches. As part of that commit we changed some "%lx" formats to "%llx" where the type is actually unsigned long long. Unfortunately prom_printf() doesn't know how to print "%llx", it just prints a literal "lx", eg: reserved memory map: lx - lx lx - lx prom_printf() also doesn't know how to print "%u" (only "%lu"), it just prints a literal "u", eg: Max number of cores passed to firmware: u (NR_CPUS = 2048) Instead of: Max number of cores passed to firmware: 2048 (NR_CPUS = 2048) This commit adds support for the missing formatters. Fixes: eae5f709a4d7 ("powerpc: Add __printf verification to prom_printf") Reported-by: Michael Ellerman <mpe@ellerman.id.au> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Mathieu Malaterre <malat@debian.org> Tested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-01powerpc/kbuild: Use flags variables rather than overriding LD/CC/ASNicholas Piggin2-11/+17
The powerpc toolchain can compile combinations of 32/64 bit and big/little endian, so it's convenient to consider, e.g., `CC -m64 -mbig-endian` To be the C compiler for the purpose of invoking it to build target artifacts. So overriding the CC variable to include these flags works for this purpose. Unfortunately that is not compatible with the way the proposed new Kconfig macro language will work. After previous patches in this series, these flags can be carefully passed in using flags instead. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-01powerpc/kbuild: Remove CROSS32 defines from top level powerpc MakefileNicholas Piggin3-16/+22
Switch VDSO32 build over to use CROSS32_COMPILE directly, and have it pass in -m32 after the standard c_flags. This allows endianness overrides to be removed and the endian and bitness flags moved into standard flags variables. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-01powerpc/kbuild: Set default generic machine type for 32-bit compileNicholas Piggin1-0/+8
Some 64-bit toolchains uses the wrong ISA variant for compiling 32-bit kernels, even with -m32. Debian's powerpc64le is one such case, and that is because it is built with --with-cpu=power8. So when cross compiling a 32-bit kernel with a 64-bit toolchain, set -mcpu=powerpc initially, which is the generic 32-bit powerpc machine type and scheduling model. CPU and platform code can override this with subsequent -mcpu flags if necessary. This is not done for 32-bit toolchains otherwise it would override their defaults, which are presumably set appropriately for the environment (moreso than a 64-bit cross compiler). This fixes a lot of build failures due to incompatible assembly when compiling 32-bit kernel with the Debian powerpc64le 64-bit toolchain. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-01KVM: PPC: Book3S PR: Enable kvmppc_get/set_one_reg_pr() for HTM registersSimon Guo1-0/+133
We need to migrate PR KVM during transaction and userspace will use kvmppc_get_one_reg_pr()/kvmppc_set_one_reg_pr() APIs to get/set transaction checkpoint state. This patch adds support for that. So far, QEMU on PR KVM doesn't fully function for migration but the savevm/loadvm can be done against a RHEL72 guest. During savevm/ loadvm procedure, the kvm ioctls will be invoked as well. Test has been performed to savevm/loadvm for a guest running a HTM test program: https://github.com/justdoitqd/publicFiles/blob/master/test-tm-mig.c Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S: Remove load/put vcpu for KVM_GET_REGS/KVM_SET_REGSSimon Guo1-6/+0
In both HV and PR KVM, the KVM_SET_REGS/KVM_GET_REGS ioctl should be able to perform without the vcpu loaded. Since the vcpu mutex locking/unlock has been moved out of vcpu_load() /vcpu_put(), KVM_SET_REGS/KVM_GET_REGS don't need to do ioctl with the vcpu loaded anymore. This patch removes vcpu_load()/vcpu_put() from KVM_SET_REGS/KVM_GET_REGS ioctl. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Remove load/put vcpu for KVM_GET/SET_ONE_REG ioctlSimon Guo1-2/+0
Since the vcpu mutex locking/unlock has been moved out of vcpu_load() /vcpu_put(), KVM_GET_ONE_REG and KVM_SET_ONE_REG doesn't need to do ioctl with loading vcpu anymore. This patch removes vcpu_load()/vcpu_put() from KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctl. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctlSimon Guo1-3/+6
Although we already have kvm_arch_vcpu_async_ioctl() which doesn't require ioctl to load vcpu, the sync ioctl code need to be cleaned up when CONFIG_HAVE_KVM_VCPU_ASYNC_IOCTL is not configured. This patch moves vcpu_load/vcpu_put down to each ioctl switch case so that each ioctl can decide to do vcpu_load/vcpu_put or not independently. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Enable HTM for PR KVM for KVM_CHECK_EXTENSION ioctlSimon Guo1-3/+2
With current patch set, PR KVM now supports HTM. So this patch turns it on for PR KVM. Tested with: https://github.com/justdoitqd/publicFiles/blob/master/test_kvm_htm_cap.c Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Support TAR handling for PR KVM HTMSimon Guo4-7/+38
Currently guest kernel doesn't handle TAR facility unavailable and it always runs with TAR bit on. PR KVM will lazily enable TAR. TAR is not a frequent-use register and it is not included in SVCPU struct. Due to the above, the checkpointed TAR val might be a bogus TAR val. To solve this issue, we will make vcpu->arch.fscr tar bit consistent with shadow_fscr when TM is enabled. At the end of emulating treclaim., the correct TAR val need to be loaded into the register if FSCR_TAR bit is on. At the beginning of emulating trechkpt., TAR needs to be flushed so that the right tar val can be copied into tar_tm. Tested with: tools/testing/selftests/powerpc/tm/tm-tar tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar (remove DSCR/PPR related testing). Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add guard code to prevent returning to guest with PR=0 and Transactional stateSimon Guo3-2/+19
Currently PR KVM doesn't support transaction memory in guest privileged state. This patch adds a check at setting guest msr, so that we can never return to guest with PR=0 and TS=0b10. A tabort will be emulated to indicate this and fail transaction immediately. [paulus@ozlabs.org - don't change the TM_CAUSE_MISC definition, instead use TM_CAUSE_KVM_FAC_UNAV.] Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add emulation for tabort. in privileged stateSimon Guo1-0/+68
Currently privileged-state guest will be run with TM disabled. Although the privileged-state guest cannot initiate a new transaction, it can use tabort to terminate its problem state's transaction. So it is still necessary to emulate tabort. for privileged-state guest. Tested with: https://github.com/justdoitqd/publicFiles/blob/master/test_tabort.c Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add emulation for trechkpt.Simon Guo3-1/+64
This patch adds host emulation when guest PR KVM executes "trechkpt.", which is a privileged instruction and will trap into host. We firstly copy vcpu ongoing content into vcpu tm checkpoint content, then perform kvmppc_restore_tm_pr() to do trechkpt. with updated vcpu tm checkpoint values. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add emulation for treclaim.Simon Guo1-0/+76
This patch adds support for "treclaim." emulation when PR KVM guest executes treclaim. and traps to host. We will firstly do treclaim. and save TM checkpoint. Then it is necessary to update vcpu current reg content with checkpointed vals. When rfid into guest again, those vcpu current reg content (now the checkpoint vals) will be loaded into regs. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Restore NV regs after emulating mfspr from TM SPRsSimon Guo1-2/+13
Currently kvmppc_handle_fac() will not update NV GPRs and thus it can return with GUEST_RESUME. However PR KVM guest always disables MSR_TM bit in privileged state. If PR privileged-state guest is trying to read TM SPRs, it will trigger TM facility unavailable exception and fall into kvmppc_handle_fac(). Then the emulation will be done by kvmppc_core_emulate_mfspr_pr(). The mfspr instruction can include a RT with NV reg. So it is necessary to restore NV GPRs at this case, to reflect the update to NV RT. This patch make kvmppc_handle_fac() return GUEST_RESUME_NV for TM facility unavailable exceptions in guest privileged state. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Reviewed-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Always fail transactions in guest privileged stateSimon Guo3-1/+52
Currently the kernel doesn't use transaction memory. And there is an issue for privileged state in the guest that: tbegin/tsuspend/tresume/tabort TM instructions can impact MSR TM bits without trapping into the PR host. So following code will lead to a false mfmsr result: tbegin <- MSR bits update to Transaction active. beq <- failover handler branch mfmsr <- still read MSR bits from magic page with transaction inactive. It is not an issue for non-privileged guest state since its mfmsr is not patched with magic page and will always trap into the PR host. This patch will always fail tbegin attempt for privileged state in the guest, so that the above issue is prevented. It is benign since currently (guest) kernel doesn't initiate a transaction. Test case: https://github.com/justdoitqd/publicFiles/blob/master/test_tbegin_pr.c Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Emulate mtspr/mfspr using active TM SPRsSimon Guo3-11/+50
The mfspr/mtspr on TM SPRs(TEXASR/TFIAR/TFHAR) are non-privileged instructions and can be executed by PR KVM guest in problem state without trapping into the host. We only emulate mtspr/mfspr texasr/tfiar/tfhar in guest PR=0 state. When we are emulating mtspr tm sprs in guest PR=0 state, the emulation result needs to be visible to guest PR=1 state. That is, the actual TM SPR val should be loaded into actual registers. We already flush TM SPRs into vcpu when switching out of CPU, and load TM SPRs when switching back. This patch corrects mfspr()/mtspr() emulation for TM SPRs to make the actual source/dest be the actual TM SPRs. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add math support for PR KVM HTMSimon Guo1-0/+35
The math registers will be saved into vcpu->arch.fp/vr and corresponding vcpu->arch.fp_tm/vr_tm area. We flush or giveup the math regs into vcpu->arch.fp/vr before saving transaction. After transaction is restored, the math regs will be loaded back into regs. If there is a FP/VEC/VSX unavailable exception during transaction active state, the math checkpoint content might be incorrect and we need to do treclaim./load the correct checkpoint val/trechkpt. sequence to retry the transaction. That will make our solution complicated. To solve this issue, we always make the hardware guest MSR math bits (shadow_msr) consistent with the MSR val which guest sees (kvmppc_get_msr()) when guest msr is with tm enabled. Then all FP/VEC/VSX unavailable exception can be delivered to guest and guest handles the exception by itself. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add transaction memory save/restore skeletonSimon Guo3-1/+36
The transaction memory checkpoint area save/restore behavior is triggered when VCPU qemu process is switching out/into CPU, i.e. at kvmppc_core_vcpu_put_pr() and kvmppc_core_vcpu_load_pr(). MSR TM active state is determined by TS bits: active: 10(transactional) or 01 (suspended) inactive: 00 (non-transactional) We don't "fake" TM functionality for guest. We "sync" guest virtual MSR TM active state(10 or 01) with shadow MSR. That is to say, we don't emulate a transactional guest with a TM inactive MSR. TM SPR support(TFIAR/TFAR/TEXASR) has already been supported by commit 9916d57e64a4 ("KVM: PPC: Book3S PR: Expose TM registers"). Math register support (FPR/VMX/VSX) will be done at subsequent patch. Whether TM context need to be saved/restored can be determined by kvmppc_get_msr() TM active state: * TM active - save/restore TM context * TM inactive - no need to do so and only save/restore TM SPRs. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Suggested-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add kvmppc_save/restore_tm_sprs() APIsSimon Guo1-0/+22
This patch adds 2 new APIs, kvmppc_save_tm_sprs() and kvmppc_restore_tm_sprs(), for the purpose of TEXASR/TFIAR/TFHAR save/restore. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add new kvmppc_copyto/from_vcpu_tm APIsSimon Guo1-0/+41
This patch adds 2 new APIs: kvmppc_copyto_vcpu_tm() and kvmppc_copyfrom_vcpu_tm(). These 2 APIs will be used to copy from/to TM data between VCPU_TM/VCPU area. PR KVM will use these APIs for treclaim. or trechkpt. emulation. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Avoid changing TS bits when exiting guestSimon Guo1-0/+13
PR KVM host usually runs with TM enabled in its host MSR value, and with non-transactional TS value. When a guest with TM active traps into PR KVM host, the rfid at the tail of kvmppc_interrupt_pr() will try to switch TS bits from S0 (Suspended & TM disabled) to N1 (Non-transactional & TM enabled). That will leads to TM Bad Thing interrupt. This patch manually sets target TS bits unchanged to avoid this exception. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Implement RFID TM behavior to suppress change from S0 to N0Simon Guo1-2/+19
According to ISA specification for RFID, in MSR TM disabled and TS suspended state (S0), if the target MSR is TM disabled and TS state is inactive (N0), rfid should suppress this update. This patch makes the RFID emulation of PR KVM consistent with this. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Sync TM bits to shadow msr for problem state guestSimon Guo1-23/+50
MSR TS bits can be modified with non-privileged instruction such as tbegin./tend. That means guest can change MSR value "silently" without notifying host. It is necessary to sync the TM bits to host so that host can calculate shadow msr correctly. Note, privileged mode in the guest will always fail transactions so we only take care of problem state mode in the guest. The logic is put into kvmppc_copy_from_svcpu() so that kvmppc_handle_exit_pr() can use correct MSR TM bits even when preemption occurs. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Pass through MSR TM and TS bits to shadow_msrSimon Guo1-0/+5
PowerPC TM functionality needs MSR TM/TS bits support in hardware level. Guest TM functionality can not be emulated with "fake" MSR (msr in magic page) TS bits. This patch syncs TM/TS bits in shadow_msr with the MSR value in magic page, so that the MSR TS value which guest sees is consistent with actual MSR bits running in guest. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Transition to Suspended state when injecting interruptSimon Guo1-1/+10
This patch simulates interrupt behavior per Power ISA while injecting interrupt in PR KVM: - When interrupt happens, transactional state should be suspended. kvmppc_mmu_book3s_64_reset_msr() will be invoked when injecting an interrupt. This patch performs this ISA logic in kvmppc_mmu_book3s_64_reset_msr(). Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add C function wrapper for _kvmppc_save/restore_tm()Simon Guo3-5/+101
Currently __kvmppc_save/restore_tm() APIs can only be invoked from assembly function. This patch adds C function wrappers for them so that they can be safely called from C function. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Turn on FP/VSX/VMX MSR bits in kvmppc_save_tm()Simon Guo1-0/+2
kvmppc_save_tm() invokes store_fp_state/store_vr_state(). So it is mandatory to turn on FP/VSX/VMX MSR bits for its execution, just like what kvmppc_restore_tm() did. Previously HV KVM has turned the bits on outside of function kvmppc_save_tm(). Now we include this bit change in kvmppc_save_tm() so that the logic is cleaner. And PR KVM can reuse it later. Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Reviewed-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01KVM: PPC: Book3S PR: Add guest MSR parameter for kvmppc_save_tm()/kvmppc_restore_tm()Simon Guo2-47/+57
HV KVM and PR KVM need different MSR source to indicate whether treclaim. or trecheckpoint. is necessary. This patch add new parameter (guest MSR) for these kvmppc_save_tm/ kvmppc_restore_tm() APIs: - For HV KVM, it is VCPU_MSR - For PR KVM, it is current host MSR or VCPU_SHADOW_SRR1 This enhancement enables these 2 APIs to be reused by PR KVM later. And the patch keeps HV KVM logic unchanged. This patch also reworks kvmppc_save_tm()/kvmppc_restore_tm() to have a clean ABI: r3 for vcpu and r4 for guest_msr. During kvmppc_save_tm/kvmppc_restore_tm(), the R1 need to be saved or restored. Currently the R1 is saved into HSTATE_HOST_R1. In PR KVM, we are going to add a C function wrapper for kvmppc_save_tm/kvmppc_restore_tm() where the R1 will be incremented with added stackframe and save into HSTATE_HOST_R1. There are several places in HV KVM to load HSTATE_HOST_R1 as R1, and we don't want to bring risk or confusion by TM code. This patch will use HSTATE_SCRATCH2 to save/restore R1 in kvmppc_save_tm/kvmppc_restore_tm() to avoid future confusion, since the r1 is actually a temporary/scratch value to be saved/stored. [paulus@ozlabs.org - rebased on top of 7b0e827c6970 ("KVM: PPC: Book3S HV: Factor fake-suspend handling out of kvmppc_save/restore_tm", 2018-05-30)] Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>