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2023-05-01Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "s390: - More phys_to_virt conversions - Improvement of AP management for VSIE (nested virtualization) ARM64: - Numerous fixes for the pathological lock inversion issue that plagued KVM/arm64 since... forever. - New framework allowing SMCCC-compliant hypercalls to be forwarded to userspace, hopefully paving the way for some more features being moved to VMMs rather than be implemented in the kernel. - Large rework of the timer code to allow a VM-wide offset to be applied to both virtual and physical counters as well as a per-timer, per-vcpu offset that complements the global one. This last part allows the NV timer code to be implemented on top. - A small set of fixes to make sure that we don't change anything affecting the EL1&0 translation regime just after having having taken an exception to EL2 until we have executed a DSB. This ensures that speculative walks started in EL1&0 have completed. - The usual selftest fixes and improvements. x86: - Optimize CR0.WP toggling by avoiding an MMU reload when TDP is enabled, and by giving the guest control of CR0.WP when EPT is enabled on VMX (VMX-only because SVM doesn't support per-bit controls) - Add CR0/CR4 helpers to query single bits, and clean up related code where KVM was interpreting kvm_read_cr4_bits()'s "unsigned long" return as a bool - Move AMD_PSFD to cpufeatures.h and purge KVM's definition - Avoid unnecessary writes+flushes when the guest is only adding new PTEs - Overhaul .sync_page() and .invlpg() to utilize .sync_page()'s optimizations when emulating invalidations - Clean up the range-based flushing APIs - Revamp the TDP MMU's reaping of Accessed/Dirty bits to clear a single A/D bit using a LOCK AND instead of XCHG, and skip all of the "handle changed SPTE" overhead associated with writing the entire entry - Track the number of "tail" entries in a pte_list_desc to avoid having to walk (potentially) all descriptors during insertion and deletion, which gets quite expensive if the guest is spamming fork() - Disallow virtualizing legacy LBRs if architectural LBRs are available, the two are mutually exclusive in hardware - Disallow writes to immutable feature MSRs (notably PERF_CAPABILITIES) after KVM_RUN, similar to CPUID features - Overhaul the vmx_pmu_caps selftest to better validate PERF_CAPABILITIES - Apply PMU filters to emulated events and add test coverage to the pmu_event_filter selftest - AMD SVM: - Add support for virtual NMIs - Fixes for edge cases related to virtual interrupts - Intel AMX: - Don't advertise XTILE_CFG in KVM_GET_SUPPORTED_CPUID if XTILE_DATA is not being reported due to userspace not opting in via prctl() - Fix a bug in emulation of ENCLS in compatibility mode - Allow emulation of NOP and PAUSE for L2 - AMX selftests improvements - Misc cleanups MIPS: - Constify MIPS's internal callbacks (a leftover from the hardware enabling rework that landed in 6.3) Generic: - Drop unnecessary casts from "void *" throughout kvm_main.c - Tweak the layout of "struct kvm_mmu_memory_cache" to shrink the struct size by 8 bytes on 64-bit kernels by utilizing a padding hole Documentation: - Fix goof introduced by the conversion to rST" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (211 commits) KVM: s390: pci: fix virtual-physical confusion on module unload/load KVM: s390: vsie: clarifications on setting the APCB KVM: s390: interrupt: fix virtual-physical confusion for next alert GISA KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() KVM: selftests: Test the PMU event "Instructions retired" KVM: selftests: Copy full counter values from guest in PMU event filter test KVM: selftests: Use error codes to signal errors in PMU event filter test KVM: selftests: Print detailed info in PMU event filter asserts KVM: selftests: Add helpers for PMC asserts in PMU event filter test KVM: selftests: Add a common helper for the PMU event filter guest code KVM: selftests: Fix spelling mistake "perrmited" -> "permitted" KVM: arm64: vhe: Drop extra isb() on guest exit KVM: arm64: vhe: Synchronise with page table walker on MMU update KVM: arm64: pkvm: Document the side effects of kvm_flush_dcache_to_poc() KVM: arm64: nvhe: Synchronise with page table walker on TLBI KVM: arm64: Handle 32bit CNTPCTSS traps KVM: arm64: nvhe: Synchronise with page table walker on vcpu run KVM: arm64: vgic: Don't acquire its_lock before config_lock KVM: selftests: Add test to verify KVM's supported XCR0 ...
2023-04-28Merge tag 'powerpc-6.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add support for building the kernel using PC-relative addressing on Power10. - Allow HV KVM guests on Power10 to use prefixed instructions. - Unify support for the P2020 CPU (85xx) into a single machine description. - Always build the 64-bit kernel with 128-bit long double. - Drop support for several obsolete 2000's era development boards as identified by Paul Gortmaker. - A series fixing VFIO on Power since some generic changes. - Various other small features and fixes. Thanks to Alexey Kardashevskiy, Andrew Donnellan, Benjamin Gray, Bo Liu, Christophe Leroy, Dan Carpenter, David Binderman, Ira Weiny, Joel Stanley, Kajol Jain, Kautuk Consul, Liang He, Luis Chamberlain, Masahiro Yamada, Michael Neuling, Nathan Chancellor, Nathan Lynch, Nicholas Miehlbradt, Nicholas Piggin, Nick Desaulniers, Nysal Jan K.A, Pali Rohár, Paul Gortmaker, Paul Mackerras, Petr Vaněk, Randy Dunlap, Rob Herring, Sachin Sant, Sean Christopherson, Segher Boessenkool, and Timothy Pearson. * tag 'powerpc-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (156 commits) powerpc/64s: Disable pcrel code model on Clang powerpc: Fix merge conflict between pcrel and copy_thread changes powerpc/configs/powernv: Add IGB=y powerpc/configs/64s: Drop JFS Filesystem powerpc/configs/64s: Use EXT4 to mount EXT2 filesystems powerpc/configs: Make pseries_defconfig an alias for ppc64le_guest powerpc/configs: Make pseries_le an alias for ppc64le_guest powerpc/configs: Incorporate generic kvm_guest.config into guest configs powerpc/configs: Add IBMVETH=y and IBMVNIC=y to guest configs powerpc/configs/64s: Enable Device Mapper options powerpc/configs/64s: Enable PSTORE powerpc/configs/64s: Enable VLAN support powerpc/configs/64s: Enable BLK_DEV_NVME powerpc/configs/64s: Drop REISERFS powerpc/configs/64s: Use SHA512 for module signatures powerpc/configs/64s: Enable IO_STRICT_DEVMEM powerpc/configs/64s: Enable SCHEDSTATS powerpc/configs/64s: Enable DEBUG_VM & other options powerpc/configs/64s: Enable EMULATED_STATS powerpc/configs/64s: Enable KUNIT and most tests ...
2023-04-03KVM: PPC: Make kvmppc_get_last_inst() produce a ppc_inst_tPaul Mackerras
This changes kvmppc_get_last_inst() so that the instruction it fetches is returned in a ppc_inst_t variable rather than a u32. This will allow us to return a 64-bit prefixed instruction on those 64-bit machines that implement Power ISA v3.1 or later, such as POWER10. On 32-bit platforms, ppc_inst_t is 32 bits wide, and is turned back into a u32 by ppc_inst_val, which is an identity operation on those platforms. Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Tested-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/ZAgsiPlL9O7KnlZZ@cleo
2023-04-03KVM: PPC: Book3S HV: Set SRR1[PREFIX] bit on injected interruptsNicholas Piggin
Pass the hypervisor (H)SRR1[PREFIX] indication through to synchronous interrupts injected into the guest. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230330103224.3589928-3-npiggin@gmail.com
2023-04-03KVM: PPC: Permit SRR1 flags in more injected interrupt typesNicholas Piggin
The prefix architecture in ISA v3.1 introduces a prefixed bit in SRR1 for many types of synchronous interrupts which is set when the interrupt is caused by a prefixed instruction. This requires KVM to be able to set this bit when injecting interrupts into a guest. Plumb through the SRR1 "flags" argument to the core_queue APIs where it's missing for this. For now they are set to 0, which is no change. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Fixup kvmppc_core_queue_alignment() in booke.c] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230330103224.3589928-2-npiggin@gmail.com
2023-03-31KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependentAlexey Kardashevskiy
When introduced, IRQFD resampling worked on POWER8 with XICS. However KVM on POWER9 has never implemented it - the compatibility mode code ("XICS-on-XIVE") misses the kvm_notify_acked_irq() call and the native XIVE mode does not handle INTx in KVM at all. This moved the capability support advertising to platforms and stops advertising it on XIVE, i.e. POWER9 and later. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Acked-by: Anup Patel <anup@brainfault.org> Acked-by: Nicholas Piggin <npiggin@gmail.com> Message-Id: <20220504074807.3616813-1-aik@ozlabs.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-03-16KVM: Change return type of kvm_arch_vm_ioctl() to "int"Thomas Huth
All kvm_arch_vm_ioctl() implementations now only deal with "int" types as return values, so we can change the return type of these functions to use "int" instead of "long". Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Anup Patel <anup@brainfault.org> Message-Id: <20230208140105.655814-7-thuth@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29KVM: Opt out of generic hardware enabling on s390 and PPCSean Christopherson
Allow architectures to opt out of the generic hardware enabling logic, and opt out on both s390 and PPC, which don't need to manually enable virtualization as it's always on (when available). In addition to letting s390 and PPC drop a bit of dead code, this will hopefully also allow ARM to clean up its related code, e.g. ARM has its own per-CPU flag to track which CPUs have enable hardware due to the need to keep hardware enabled indefinitely when pKVM is enabled. Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Anup Patel <anup@brainfault.org> Message-Id: <20221130230934.1014142-50-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29KVM: Drop kvm_arch_check_processor_compat() hookSean Christopherson
Drop kvm_arch_check_processor_compat() and its support code now that all architecture implementations are nops. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Eric Farman <farman@linux.ibm.com> # s390 Acked-by: Anup Patel <anup@brainfault.org> Reviewed-by: Kai Huang <kai.huang@intel.com> Message-Id: <20221130230934.1014142-33-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29KVM: Drop kvm_arch_{init,exit}() hooksSean Christopherson
Drop kvm_arch_init() and kvm_arch_exit() now that all implementations are nops. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> # s390 Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Acked-by: Anup Patel <anup@brainfault.org> Message-Id: <20221130230934.1014142-30-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29KVM: PPC: Move processor compatibility check to module initSean Christopherson
Move KVM PPC's compatibility checks to their respective module_init() hooks, there's no need to wait until KVM's common compat check, nor is there a need to perform the check on every CPU (provided by common KVM's hook), as the compatibility checks operate on global data. arch/powerpc/include/asm/cputable.h: extern struct cpu_spec *cur_cpu_spec; arch/powerpc/kvm/book3s.c: return 0 arch/powerpc/kvm/e500.c: strcmp(cur_cpu_spec->cpu_name, "e500v2") arch/powerpc/kvm/e500mc.c: strcmp(cur_cpu_spec->cpu_name, "e500mc") strcmp(cur_cpu_spec->cpu_name, "e5500") strcmp(cur_cpu_spec->cpu_name, "e6500") Cc: Fabiano Rosas <farosas@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Message-Id: <20221130230934.1014142-27-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29KVM: Drop arch hardware (un)setup hooksSean Christopherson
Drop kvm_arch_hardware_setup() and kvm_arch_hardware_unsetup() now that all implementations are nops. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> # s390 Acked-by: Anup Patel <anup@brainfault.org> Message-Id: <20221130230934.1014142-10-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-09KVM: replace direct irq.h inclusionPaolo Bonzini
virt/kvm/irqchip.c is including "irq.h" from the arch-specific KVM source directory (i.e. not from arch/*/include) for the sole purpose of retrieving irqchip_in_kernel. Making the function inline in a header that is already included, such as asm/kvm_host.h, is not possible because it needs to look at struct kvm which is defined after asm/kvm_host.h is included. So add a kvm_arch_irqchip_in_kernel non-inline function; irqchip_in_kernel() is only performance critical on arm64 and x86, and the non-inline function is enough on all other architectures. irq.h can then be deleted from all architectures except x86. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-10-09Merge tag 'powerpc-6.1-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Remove our now never-true definitions for pgd_huge() and p4d_leaf(). - Add pte_needs_flush() and huge_pmd_needs_flush() for 64-bit. - Add support for syscall wrappers. - Add support for KFENCE on 64-bit. - Update 64-bit HV KVM to use the new guest state entry/exit accounting API. - Support execute-only memory when using the Radix MMU (P9 or later). - Implement CONFIG_PARAVIRT_TIME_ACCOUNTING for pseries guests. - Updates to our linker script to move more data into read-only sections. - Allow the VDSO to be randomised on 32-bit. - Many other small features and fixes. Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev, Christophe Leroy, David Hildenbrand, Disha Goel, Fabiano Rosas, Gaosheng Cui, Gustavo A. R. Silva, Haren Myneni, Hari Bathini, Jilin Yuan, Joel Stanley, Kajol Jain, Kees Cook, Krzysztof Kozlowski, Laurent Dufour, Liang He, Li Huafei, Lukas Bulwahn, Madhavan Srinivasan, Nathan Chancellor, Nathan Lynch, Nicholas Miehlbradt, Nicholas Piggin, Pali Rohár, Rohan McLure, Russell Currey, Sachin Sant, Segher Boessenkool, Shrikanth Hegde, Tyrel Datwyler, Wolfram Sang, ye xingchen, and Zheng Yongjun. * tag 'powerpc-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) KVM: PPC: Book3S HV: Fix stack frame regs marker powerpc: Don't add __powerpc_ prefix to syscall entry points powerpc/64s/interrupt: Fix stack frame regs marker powerpc/64: Fix msr_check_and_set/clear MSR[EE] race powerpc/64s/interrupt: Change must-hard-mask interrupt check from BUG to WARN powerpc/pseries: Add firmware details to the hardware description powerpc/powernv: Add opal details to the hardware description powerpc: Add device-tree model to the hardware description powerpc/64: Add logical PVR to the hardware description powerpc: Add PVR & CPU name to hardware description powerpc: Add hardware description string powerpc/configs: Enable PPC_UV in powernv_defconfig powerpc/configs: Update config files for removed/renamed symbols powerpc/mm: Fix UBSAN warning reported on hugetlb powerpc/mm: Always update max/min_low_pfn in mem_topology_setup() powerpc/mm/book3s/hash: Rename flush_tlb_pmd_range powerpc: Drops STABS_DEBUG from linker scripts powerpc/64s: Remove lost/old comment powerpc/64s: Remove old STAB comment powerpc: remove orphan systbl_chk.sh ...
2022-09-28KVM: PPC: Book3S HV: Fix decrementer migrationFabiano Rosas
We used to have a workaround[1] for a hang during migration that was made ineffective when we converted the decrementer expiry to be relative to guest timebase. The point of the workaround was that in the absence of an explicit decrementer expiry value provided by userspace during migration, KVM needs to initialize dec_expires to a value that will result in an expired decrementer after subtracting the current guest timebase. That stops the vcpu from hanging after migration due to a decrementer that's too large. If the dec_expires is now relative to guest timebase, its initialization needs to be guest timebase-relative as well, otherwise we end up with a decrementer expiry that is still larger than the guest timebase. 1- https://git.kernel.org/torvalds/c/5855564c8ab2 Fixes: 3c1a4322bba7 ("KVM: PPC: Book3S HV: Change dec_expires to be relative to guest timebase") Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220816222517.1916391-1-farosas@linux.ibm.com
2022-09-26KVM: remove KVM_REQ_UNHALTPaolo Bonzini
KVM_REQ_UNHALT is now unnecessary because it is replaced by the return value of kvm_vcpu_block/kvm_vcpu_halt. Remove it. No functional change intended. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Marc Zyngier <maz@kernel.org> Message-Id: <20220921003201.1441511-13-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-20powerpc: Don't include asm/setup.h in asm/machdep.hChristophe Leroy
asm/machdep.h doesn't need asm/setup.h Remove it. Add it directly in files that needs it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/3b1dfb19a2c3265fb4abc2bfc7b6eae9261a998b.1654966508.git.christophe.leroy@csgroup.eu
2022-05-19Merge branch 'topic/ppc-kvm' into nextMichael Ellerman
Merge our KVM topic branch.
2022-05-13KVM: PPC: Book3S HV: Use IDA allocator for LPID allocatorNicholas Piggin
This removes the fixed-size lpid_inuse array. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220123120043.3586018-4-npiggin@gmail.com
2022-05-13KVM: PPC: Remove kvmppc_claim_lpidNicholas Piggin
Removing kvmppc_claim_lpid makes the lpid allocator API a bit simpler to change the underlying implementation in a future patch. The host LPID is always 0, so that can be a detail of the allocator. If the allocator range is restricted, that can reserve LPIDs at the top of the range. This allows kvmppc_claim_lpid to be removed. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220123120043.3586018-2-npiggin@gmail.com
2022-05-08powerpc: Add missing headersChristophe Leroy
Don't inherit headers "by chances" from asm/prom.h, asm/mpc52xx.h, asm/pci.h etc... Include the needed headers, and remove asm/prom.h when it was needed exclusively for pulling necessary headers. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/be8bdc934d152a7d8ee8d1a840d5596e2f7d85e0.1646767214.git.christophe.leroy@csgroup.eu
2022-04-21KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abusedSean Christopherson
Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com> Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-08KVM: PPC: Use KVM_CAP_PPC_AIL_MODE_3Nicholas Piggin
Use KVM_CAP_PPC_AIL_MODE_3 to advertise the capability to set the AIL resource mode to 3 with the H_SET_MODE hypercall. This capability differs between processor types and KVM types (PR, HV, Nested HV), and affects guest-visible behaviour. QEMU will implement a cap-ail-mode-3 to control this behaviour[1], and use the KVM CAP if available to determine KVM support[2]. [1] https://lists.nongnu.org/archive/html/qemu-ppc/2022-02/msg00437.html [2] https://lists.nongnu.org/archive/html/qemu-ppc/2022-02/msg00439.html Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> [mpe: Rebase onto 93b71801a827 from kvm-ppc-cap-210 branch, add EXPORT_SYMBOL] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220222064727.2314380-4-npiggin@gmail.com
2022-02-03KVM: PPC: Decrement module refcount if init_vm failsFabiano Rosas
We increment the reference count for KVM-HV/PR before the call to kvmppc_core_init_vm. If that function fails we need to decrement the refcount. Also remove the check on kvm_ops->owner because try_module_get can handle a NULL module. Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220125155735.1018683-5-farosas@linux.ibm.com
2022-02-02KVM: PPC: Merge powerpc's debugfs entry content into generic entryAlexey Kardashevskiy
At the moment KVM on PPC creates 4 types of entries under the kvm debugfs: 1) "%pid-%fd" per a KVM instance (for all platforms); 2) "vm%pid" (for PPC Book3s HV KVM); 3) "vm%u_vcpu%u_timing" (for PPC Book3e KVM); 4) "kvm-xive-%p" (for XIVE PPC Book3s KVM, the same for XICS); The problem with this is that multiple VMs per process is not allowed for 2) and 3) which makes it possible for userspace to trigger errors when creating duplicated debugfs entries. This merges all these into 1). This defines kvm_arch_create_kvm_debugfs() similar to kvm_arch_create_vcpu_debugfs(). This defines 2 hooks in kvmppc_ops that allow specific KVM implementations add necessary entries, this adds the _e500 suffix to kvmppc_create_vcpu_debugfs_e500() to make it clear what platform it is for. This makes use of already existing kvm_arch_create_vcpu_debugfs() on PPC. This removes no more used debugfs_dir pointers from PPC kvm_arch structs. This stops removing vcpu entries as once created vcpus stay around for the entire life of a VM and removed when the KVM instance is closed, see commit d56f5136b010 ("KVM: let kvm_destroy_vm_debugfs clean up vCPU debugfs directories"). Suggested-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220111005404.162219-1-aik@ozlabs.ru
2022-01-31KVM: PPC: Book3s: mmio: Deliver DSI after emulation failureFabiano Rosas
MMIO emulation can fail if the guest uses an instruction that we are not prepared to emulate. Since these instructions can be and most likely are valid ones, this is (slightly) closer to an access fault than to an illegal instruction, so deliver a Data Storage interrupt instead of a Program interrupt. BookE ignores bad faults, so it will keep using a Program interrupt because a DSI would cause a fault loop in the guest. Suggested-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220125215655.1026224-6-farosas@linux.ibm.com
2022-01-31KVM: PPC: mmio: Return to guest after emulation failureFabiano Rosas
If MMIO emulation fails we don't want to crash the whole guest by returning to userspace. The original commit bbf45ba57eae ("KVM: ppc: PowerPC 440 KVM implementation") added a todo: /* XXX Deliver Program interrupt to guest. */ and later the commit d69614a295ae ("KVM: PPC: Separate loadstore emulation from priv emulation") added the Program interrupt injection but in another file, so I'm assuming it was missed that this block needed to be altered. Also change the message to a ratelimited one since we're letting the guest run and it could flood the host logs. Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220125215655.1026224-5-farosas@linux.ibm.com
2022-01-31KVM: PPC: mmio: Reject instructions that access more than mmio.data sizeFabiano Rosas
The MMIO interface between the kernel and userspace uses a structure that supports a maximum of 8-bytes of data. Instructions that access more than that need to be emulated in parts. We currently don't have generic support for splitting the emulation in parts and each set of instructions needs to be explicitly included. There's already an error message being printed when a load or store exceeds the mmio.data buffer but we don't fail the emulation until later at kvmppc_complete_mmio_load and even then we allow userspace to make a partial copy of the data, which ends up overwriting some fields of the mmio structure. This patch makes the emulation fail earlier at kvmppc_handle_load|store, which will send a Program interrupt to the guest. This is better than allowing the guest to proceed with partial data. Note that this was caught in a somewhat artificial scenario using quadword instructions (lq/stq), there's no account of an actual guest in the wild running instructions that are not properly emulated. (While here, remove the "bad MMIO" messages. The caller already has an error message.) Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220125215655.1026224-4-farosas@linux.ibm.com
2022-01-31KVM: PPC: Fix vmx/vsx mixup in mmio emulationFabiano Rosas
The MMIO emulation code for vector instructions is duplicated between VSX and VMX. When emulating VMX we should check the VMX copy size instead of the VSX one. Fixes: acc9eb9305fe ("KVM: PPC: Reimplement LOAD_VMX/STORE_VMX instruction ...") Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220125215655.1026224-3-farosas@linux.ibm.com
2022-01-31KVM: PPC: Book3S HV: Stop returning internal values to userspaceFabiano Rosas
Our kvm_arch_vcpu_ioctl_run currently returns the RESUME_HOST values to userspace, against the API of the KVM_RUN ioctl which returns 0 on success. Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220125215655.1026224-2-farosas@linux.ibm.com
2021-12-08KVM: Rename kvm_vcpu_block() => kvm_vcpu_halt()Sean Christopherson
Rename kvm_vcpu_block() to kvm_vcpu_halt() in preparation for splitting the actual "block" sequences into a separate helper (to be named kvm_vcpu_block()). x86 will use the standalone block-only path to handle non-halt cases where the vCPU is not runnable. Rename block_ns to halt_ns to match the new function name. No functional change intended. Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009021236.4122790-14-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08KVM: Force PPC to define its own rcuwait objectSean Christopherson
Do not define/reference kvm_vcpu.wait if __KVM_HAVE_ARCH_WQP is true, and instead force the architecture (PPC) to define its own rcuwait object. Allowing common KVM to directly access vcpu->wait without a guard makes it all too easy to introduce potential bugs, e.g. kvm_vcpu_block(), kvm_vcpu_on_spin(), and async_pf_execute() all operate on vcpu->wait, not the result of kvm_arch_vcpu_get_wait(), and so may do the wrong thing for PPC. Due to PPC's shenanigans with respect to callbacks and waits (it switches to the virtual core's wait object at KVM_RUN!?!?), it's not clear whether or not this fixes any bugs. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009021236.4122790-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08KVM: Stop passing kvm_userspace_memory_region to arch memslot hooksSean Christopherson
Drop the @mem param from kvm_arch_{prepare,commit}_memory_region() now that its use has been removed in all architectures. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <aa5ed3e62c27e881d0d8bc0acbc1572bc336dc19.1638817640.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: PPC: Avoid referencing userspace memory region in memslot updatesSean Christopherson
For PPC HV, get the number of pages directly from the new memslot instead of computing the same from the userspace memory region, and explicitly check for !DELETE instead of inferring the same when toggling mmio_update. The motivation for these changes is to avoid referencing the @mem param so that it can be dropped in a future commit. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <1e97fb5198be25f98ef82e63a8d770c682264cc9.1638817639.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: Let/force architectures to deal with arch specific memslot dataSean Christopherson
Pass the "old" slot to kvm_arch_prepare_memory_region() and force arch code to handle propagating arch specific data from "new" to "old" when necessary. This is a baby step towards dynamically allocating "new" from the get go, and is a (very) minor performance boost on x86 due to not unnecessarily copying arch data. For PPC HV, copy the rmap in the !CREATE and !DELETE paths, i.e. for MOVE and FLAGS_ONLY. This is functionally a nop as the previous behavior would overwrite the pointer for CREATE, and eventually discard/ignore it for DELETE. For x86, copy the arch data only for FLAGS_ONLY changes. Unlike PPC HV, x86 needs to reallocate arch data in the MOVE case as the size of x86's allocations depend on the alignment of the memslot's gfn. Opportunistically tweak kvm_arch_prepare_memory_region()'s param order to match the "commit" prototype. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> [mss: add missing RISCV kvm_arch_prepare_memory_region() change] Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <67dea5f11bbcfd71e3da5986f11e87f5dd4013f9.1638817639.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: Move wiping of the kvm->vcpus array to common codeMarc Zyngier
All architectures have similar loops iterating over the vcpus, freeing one vcpu at a time, and eventually wiping the reference off the vcpus array. They are also inconsistently taking the kvm->lock mutex when wiping the references from the array. Make this code common, which will simplify further changes. The locking is dropped altogether, as this should only be called when there is no further references on the kvm structure. Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Message-Id: <20211116160403.4074052-2-maz@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-18KVM: PPC: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUSVitaly Kuznetsov
It doesn't make sense to return the recommended maximum number of vCPUs which exceeds the maximum possible number of vCPUs. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20211116163443.88707-4-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-05Merge tag 'powerpc-5.16-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Enable STRICT_KERNEL_RWX for Freescale 85xx platforms. - Activate CONFIG_STRICT_KERNEL_RWX by default, while still allowing it to be disabled. - Add support for out-of-line static calls on 32-bit. - Fix oopses doing bpf-to-bpf calls when STRICT_KERNEL_RWX is enabled. - Fix boot hangs on e5500 due to stale value in ESR passed to do_page_fault(). - Fix several bugs on pseries in handling of device tree cache information for hotplugged CPUs, and/or during partition migration. - Various other small features and fixes. Thanks to Alexey Kardashevskiy, Alistair Popple, Anatolij Gustschin, Andrew Donnellan, Athira Rajeev, Bixuan Cui, Bjorn Helgaas, Cédric Le Goater, Christophe Leroy, Daniel Axtens, Daniel Henrique Barboza, Denis Kirjanov, Fabiano Rosas, Frederic Barrat, Gustavo A. R. Silva, Hari Bathini, Jacques de Laval, Joel Stanley, Kai Song, Kajol Jain, Laurent Vivier, Leonardo Bras, Madhavan Srinivasan, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Niklas Schnelle, Oliver O'Halloran, Rob Herring, Russell Currey, Srikar Dronamraju, Stan Johnson, Tyrel Datwyler, Uwe Kleine-König, Vasant Hegde, Wan Jiabing, and Xiaoming Ni, * tag 'powerpc-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (73 commits) powerpc/8xx: Fix Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST powerpc/32e: Ignore ESR in instruction storage interrupt handler powerpc/powernv/prd: Unregister OPAL_MSG_PRD2 notifier during module unload powerpc: Don't provide __kernel_map_pages() without ARCH_SUPPORTS_DEBUG_PAGEALLOC MAINTAINERS: Update powerpc KVM entry powerpc/xmon: fix task state output powerpc/44x/fsp2: add missing of_node_put powerpc/dcr: Use cmplwi instead of 3-argument cmpli KVM: PPC: Tick accounting should defer vtime accounting 'til after IRQ handling powerpc/security: Use a mutex for interrupt exit code patching powerpc/83xx/mpc8349emitx: Make mcu_gpiochip_remove() return void powerpc/fsl_booke: Fix setting of exec flag when setting TLBCAMs powerpc/book3e: Fix set_memory_x() and set_memory_nx() powerpc/nohash: Fix __ptep_set_access_flags() and ptep_set_wrprotect() powerpc/bpf: Fix write protecting JIT code selftests/powerpc: Use date instead of EPOCHSECONDS in mitigation-patching.sh powerpc/64s/interrupt: Fix check_return_regs_valid() false positive powerpc/boot: Set LC_ALL=C in wrapper script powerpc/64s: Default to 64K pages for 64 bit book3s Revert "powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC" ...
2021-10-09powerpc/asm: Remove UPD_CONSTR after GCC 4.9 removalNick Desaulniers
UPD_CONSTR was previously a preprocessor define for an old GCC 4.9 inline asm bug with m<> constraints. Fixes: 6563139d90ad ("powerpc: remove GCC version check for UPD_CONSTR") Suggested-by: Nathan Chancellor <nathan@kernel.org> Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210914161712.2463458-1-ndesaulniers@google.com
2021-09-30kvm: rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDSJuergen Gross
KVM_MAX_VCPU_ID is not specifying the highest allowed vcpu-id, but the number of allowed vcpu-ids. This has already led to confusion, so rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS to make its semantics more clear Suggested-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20210913135745.13944-3-jgross@suse.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-07-17KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leakNicholas Piggin
vcpu_put is not called if the user copy fails. This can result in preempt notifier corruption and crashes, among other issues. Fixes: b3cebfe8c1ca ("KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctl") Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210716024310.164448-2-npiggin@gmail.com
2021-06-22KVM: PPC: Book3S HV: Add KVM_CAP_PPC_RPT_INVALIDATE capabilityBharata B Rao
Now that we have H_RPT_INVALIDATE fully implemented, enable support for the same via KVM_CAP_PPC_RPT_INVALIDATE KVM capability Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210621085003.904767-6-bharata@linux.ibm.com
2021-02-22Merge tag 'powerpc-5.12-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A large series adding wrappers for our interrupt handlers, so that irq/nmi/user tracking can be isolated in the wrappers rather than spread in each handler. - Conversion of the 32-bit syscall handling into C. - A series from Nick to streamline our TLB flushing when using the Radix MMU. - Switch to using queued spinlocks by default for 64-bit server CPUs. - A rework of our PCI probing so that it happens later in boot, when more generic infrastructure is available. - Two small fixes to allow 32-bit little-endian processes to run on 64-bit kernels. - Other smaller features, fixes & cleanups. Thanks to: Alexey Kardashevskiy, Ananth N Mavinakayanahalli, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Cédric Le Goater, Chengyang Fan, Christophe Leroy, Christopher M. Riedl, Fabiano Rosas, Florian Fainelli, Frederic Barrat, Ganesh Goudar, Hari Bathini, Jiapeng Chong, Joseph J Allen, Kajol Jain, Markus Elfring, Michal Suchanek, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pingfan Liu, Po-Hsu Lin, Qian Cai, Ram Pai, Randy Dunlap, Sandipan Das, Stephen Rothwell, Tyrel Datwyler, Will Springer, Yury Norov, and Zheng Yongjun. * tag 'powerpc-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (188 commits) powerpc/perf: Adds support for programming of Thresholding in P10 powerpc/pci: Remove unimplemented prototypes powerpc/uaccess: Merge raw_copy_to_user_allowed() into raw_copy_to_user() powerpc/uaccess: Merge __put_user_size_allowed() into __put_user_size() powerpc/uaccess: get rid of small constant size cases in raw_copy_{to,from}_user() powerpc/64: Fix stack trace not displaying final frame powerpc/time: Remove get_tbl() powerpc/time: Avoid using get_tbl() spi: mpc52xx: Avoid using get_tbl() powerpc/syscall: Avoid storing 'current' in another pointer powerpc/32: Handle bookE debugging in C in syscall entry/exit powerpc/syscall: Do not check unsupported scv vector on PPC32 powerpc/32: Remove the counter in global_dbcr0 powerpc/32: Remove verification of MSR_PR on syscall in the ASM entry powerpc/syscall: implement system call entry/exit logic in C for PPC32 powerpc/32: Always save non volatile GPRs at syscall entry powerpc/syscall: Change condition to check MSR_RI powerpc/syscall: Save r3 in regs->orig_r3 powerpc/syscall: Use is_compat_task() powerpc/syscall: Make interrupt.c buildable on PPC32 ...
2021-02-10KVM: PPC: Don't always report hash MMU capability for P9 < DD2.2Fabiano Rosas
These machines don't support running both MMU types at the same time, so remove the KVM_CAP_PPC_MMU_HASH_V3 capability when the host is using Radix MMU. [paulus@ozlabs.org - added defensive check on kvmppc_hv_ops->hash_v3_possible] Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10KVM: PPC: Book3S HV: Introduce new capability for 2nd DAWRRavi Bangoria
Introduce KVM_CAP_PPC_DAWR1 which can be used by QEMU to query whether KVM supports 2nd DAWR or not. The capability is by default disabled even when the underlying CPU supports 2nd DAWR. QEMU needs to check and enable it manually to use the feature. Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-01-30KVM: PPC: Make the VMX instruction emulation routines staticCédric Le Goater
These are only used locally. It fixes these W=1 compile errors : ../arch/powerpc/kvm/powerpc.c:1521:5: error: no previous prototype for ‘kvmppc_get_vmx_dword’ [-Werror=missing-prototypes] 1521 | int kvmppc_get_vmx_dword(struct kvm_vcpu *vcpu, int index, u64 *val) | ^~~~~~~~~~~~~~~~~~~~ ../arch/powerpc/kvm/powerpc.c:1539:5: error: no previous prototype for ‘kvmppc_get_vmx_word’ [-Werror=missing-prototypes] 1539 | int kvmppc_get_vmx_word(struct kvm_vcpu *vcpu, int index, u64 *val) | ^~~~~~~~~~~~~~~~~~~ ../arch/powerpc/kvm/powerpc.c:1557:5: error: no previous prototype for ‘kvmppc_get_vmx_hword’ [-Werror=missing-prototypes] 1557 | int kvmppc_get_vmx_hword(struct kvm_vcpu *vcpu, int index, u64 *val) | ^~~~~~~~~~~~~~~~~~~~ ../arch/powerpc/kvm/powerpc.c:1575:5: error: no previous prototype for ‘kvmppc_get_vmx_byte’ [-Werror=missing-prototypes] 1575 | int kvmppc_get_vmx_byte(struct kvm_vcpu *vcpu, int index, u64 *val) | ^~~~~~~~~~~~~~~~~~~ Fixes: acc9eb9305fe ("KVM: PPC: Reimplement LOAD_VMX/STORE_VMX instruction mmio emulation with analyse_instr() input") Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210104143206.695198-19-clg@kaod.org
2020-12-04powerpc: Fix update form addressing in inline assemblyChristophe Leroy
In several places, inline assembly uses the "%Un" modifier to enable the use of instruction with update form addressing, but the associated "<>" constraint is missing. As mentioned in previous patch, this fails with gcc 4.9, so "<>" can't be used directly. Use UPD_CONSTR macro everywhere %Un modifier is used. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/62eab5ca595485c192de1765bdac099f633a21d0.1603358942.git.christophe.leroy@csgroup.eu
2020-08-09Merge tag 'kvm-ppc-next-5.9-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-next-5.6 PPC KVM update for 5.9 - Improvements and bug-fixes for secure VM support, giving reduced startup time and memory hotplug support. - Locking fixes in nested KVM code - Increase number of guests supported by HV KVM to 4094 - Preliminary POWER10 support
2020-07-21KVM: PPC: Protect kvm_vcpu_read_guest with srcu locksAlexey Kardashevskiy
The kvm_vcpu_read_guest/kvm_vcpu_write_guest used for nested guests eventually call srcu_dereference_check to dereference a memslot and lockdep produces a warning as neither kvm->slots_lock nor kvm->srcu lock is held and kvm->users_count is above zero (>100 in fact). This wraps mentioned VCPU read/write helpers in srcu read lock/unlock as it is done in other places. This uses vcpu->srcu_idx when possible. These helpers are only used for nested KVM so this may explain why we did not see these before. Here is an example of a warning: ============================= WARNING: suspicious RCU usage 5.7.0-rc3-le_dma-bypass.3.2_a+fstn1 #897 Not tainted ----------------------------- include/linux/kvm_host.h:633 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by qemu-system-ppc/2752: #0: c000200359016be0 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0x144/0xd80 [kvm] stack backtrace: CPU: 80 PID: 2752 Comm: qemu-system-ppc Not tainted 5.7.0-rc3-le_dma-bypass.3.2_a+fstn1 #897 Call Trace: [c0002003591ab240] [c000000000b23ab4] dump_stack+0x190/0x25c (unreliable) [c0002003591ab2b0] [c00000000023f954] lockdep_rcu_suspicious+0x140/0x164 [c0002003591ab330] [c008000004a445f8] kvm_vcpu_gfn_to_memslot+0x4c0/0x510 [kvm] [c0002003591ab3a0] [c008000004a44c18] kvm_vcpu_read_guest+0xa0/0x180 [kvm] [c0002003591ab410] [c008000004ff9bd8] kvmhv_enter_nested_guest+0x90/0xb80 [kvm_hv] [c0002003591ab980] [c008000004fe07bc] kvmppc_pseries_do_hcall+0x7b4/0x1c30 [kvm_hv] [c0002003591aba10] [c008000004fe5d30] kvmppc_vcpu_run_hv+0x10a8/0x1a30 [kvm_hv] [c0002003591abae0] [c008000004a5d954] kvmppc_vcpu_run+0x4c/0x70 [kvm] [c0002003591abb10] [c008000004a56e54] kvm_arch_vcpu_ioctl_run+0x56c/0x7c0 [kvm] [c0002003591abba0] [c008000004a3ddc4] kvm_vcpu_ioctl+0x4ac/0xd80 [kvm] [c0002003591abd20] [c0000000006ebb58] ksys_ioctl+0x188/0x210 [c0002003591abd70] [c0000000006ebc28] sys_ioctl+0x48/0xb0 [c0002003591abdb0] [c000000000042764] system_call_exception+0x1d4/0x2e0 [c0002003591abe20] [c00000000000cce8] system_call_common+0xe8/0x214 Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-07-16treewide: Remove uninitialized_var() usageKees Cook
Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs Signed-off-by: Kees Cook <keescook@chromium.org>