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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>
2020-05-27KVM: PPC: Clean up redundant 'kvm_run' parametersTianjia Zhang
In the current kvm version, 'kvm_run' has been included in the 'kvm_vcpu' structure. For historical reasons, many kvm-related function parameters retain the 'kvm_run' and 'kvm_vcpu' parameters at the same time. This patch does a unified cleanup of these remaining redundant parameters. Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-05-13kvm: Replace vcpu->swait with rcuwaitDavidlohr Bueso
The use of any sort of waitqueue (simple or regular) for wait/waking vcpus has always been an overkill and semantically wrong. Because this is per-vcpu (which is blocked) there is only ever a single waiting vcpu, thus no need for any sort of queue. As such, make use of the rcuwait primitive, with the following considerations: - rcuwait already provides the proper barriers that serialize concurrent waiter and waker. - Task wakeup is done in rcu read critical region, with a stable task pointer. - Because there is no concurrency among waiters, we need not worry about rcuwait_wait_event() calls corrupting the wait->task. As a consequence, this saves the locking done in swait when modifying the queue. This also applies to per-vcore wait for powerpc kvm-hv. The x86 tscdeadline_latency test mentioned in 8577370fb0cb ("KVM: Use simple waitqueue for vcpu->wq") shows that, on avg, latency is reduced by around 15-20% with this change. Cc: Paul Mackerras <paulus@ozlabs.org> Cc: kvmarm@lists.cs.columbia.edu Cc: linux-mips@vger.kernel.org Reviewed-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Message-Id: <20200424054837.5138-6-dave@stgolabs.net> [Avoid extra logic changes. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-13Merge branch 'kvm-amd-fixes' into HEADPaolo Bonzini
2020-05-07KVM: X86: Declare KVM_CAP_SET_GUEST_DEBUG properlyPeter Xu
KVM_CAP_SET_GUEST_DEBUG should be supported for x86 however it's not declared as supported. My wild guess is that userspaces like QEMU are using "#ifdef KVM_CAP_SET_GUEST_DEBUG" to check for the capability instead, but that could be wrong because the compilation host may not be the runtime host. The userspace might still want to keep the old "#ifdef" though to not break the guest debug on old kernels. Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20200505154750.126300-1-peterx@redhat.com> [Do the same for PPC and s390. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-21KVM: Remove redundant argument to kvm_arch_vcpu_ioctl_runTianjia Zhang
In earlier versions of kvm, 'kvm_run' was an independent structure and was not included in the vcpu structure. At present, 'kvm_run' is already included in the vcpu structure, so the parameter 'kvm_run' is redundant. This patch simplifies the function definition, removes the extra 'kvm_run' parameter, and extracts it from the 'kvm_vcpu' structure if necessary. Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Message-Id: <20200416051057.26526-1-tianjia.zhang@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-31KVM: Pass kvm_init()'s opaque param to additional arch funcsSean Christopherson
Pass @opaque to kvm_arch_hardware_setup() and kvm_arch_check_processor_compat() to allow architecture specific code to reference @opaque without having to stash it away in a temporary global variable. This will enable x86 to separate its vendor specific callback ops, which are passed via @opaque, into "init" and "runtime" ops without having to stash away the "init" ops. No functional change intended. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Tested-by: Cornelia Huck <cohuck@redhat.com> #s390 Acked-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200321202603.19355-2-sean.j.christopherson@intel.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-26KVM: PPC: Book3S HV: Add a capability for enabling secure guestsPaul Mackerras
At present, on Power systems with Protected Execution Facility hardware and an ultravisor, a KVM guest can transition to being a secure guest at will. Userspace (QEMU) has no way of knowing whether a host system is capable of running secure guests. This will present a problem in future when the ultravisor is capable of migrating secure guests from one host to another, because virtualization management software will have no way to ensure that secure guests only run in domains where all of the hosts can support secure guests. This adds a VM capability which has two functions: (a) userspace can query it to find out whether the host can support secure guests, and (b) userspace can enable it for a guest, which allows that guest to become a secure guest. If userspace does not enable it, KVM will return an error when the ultravisor does the hypercall that indicates that the guest is starting to transition to a secure guest. The ultravisor will then abort the transition and the guest will terminate. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Ram Pai <linuxram@us.ibm.com>
2020-03-19KVM: PPC: Book3S PR: Fix kernel crash with PR KVMGreg Kurz
With PR KVM, shutting down a VM causes the host kernel to crash: [ 314.219284] BUG: Unable to handle kernel data access on read at 0xc00800000176c638 [ 314.219299] Faulting instruction address: 0xc008000000d4ddb0 cpu 0x0: Vector: 300 (Data Access) at [c00000036da077a0] pc: c008000000d4ddb0: kvmppc_mmu_pte_flush_all+0x68/0xd0 [kvm_pr] lr: c008000000d4dd94: kvmppc_mmu_pte_flush_all+0x4c/0xd0 [kvm_pr] sp: c00000036da07a30 msr: 900000010280b033 dar: c00800000176c638 dsisr: 40000000 current = 0xc00000036d4c0000 paca = 0xc000000001a00000 irqmask: 0x03 irq_happened: 0x01 pid = 1992, comm = qemu-system-ppc Linux version 5.6.0-master-gku+ (greg@palmb) (gcc version 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)) #17 SMP Wed Mar 18 13:49:29 CET 2020 enter ? for help [c00000036da07ab0] c008000000d4fbe0 kvmppc_mmu_destroy_pr+0x28/0x60 [kvm_pr] [c00000036da07ae0] c0080000009eab8c kvmppc_mmu_destroy+0x34/0x50 [kvm] [c00000036da07b00] c0080000009e50c0 kvm_arch_vcpu_destroy+0x108/0x140 [kvm] [c00000036da07b30] c0080000009d1b50 kvm_vcpu_destroy+0x28/0x80 [kvm] [c00000036da07b60] c0080000009e4434 kvm_arch_destroy_vm+0xbc/0x190 [kvm] [c00000036da07ba0] c0080000009d9c2c kvm_put_kvm+0x1d4/0x3f0 [kvm] [c00000036da07c00] c0080000009da760 kvm_vm_release+0x38/0x60 [kvm] [c00000036da07c30] c000000000420be0 __fput+0xe0/0x310 [c00000036da07c90] c0000000001747a0 task_work_run+0x150/0x1c0 [c00000036da07cf0] c00000000014896c do_exit+0x44c/0xd00 [c00000036da07dc0] c0000000001492f4 do_group_exit+0x64/0xd0 [c00000036da07e00] c000000000149384 sys_exit_group+0x24/0x30 [c00000036da07e20] c00000000000b9d0 system_call+0x5c/0x68 This is caused by a use-after-free in kvmppc_mmu_pte_flush_all() which dereferences vcpu->arch.book3s which was previously freed by kvmppc_core_vcpu_free_pr(). This happens because kvmppc_mmu_destroy() is called after kvmppc_core_vcpu_free() since commit ff030fdf5573 ("KVM: PPC: Move kvm_vcpu_init() invocation to common code"). The kvmppc_mmu_destroy() helper calls one of the following depending on the KVM backend: - kvmppc_mmu_destroy_hv() which does nothing (Book3s HV) - kvmppc_mmu_destroy_pr() which undoes the effects of kvmppc_mmu_init() (Book3s PR 32-bit) - kvmppc_mmu_destroy_pr() which undoes the effects of kvmppc_mmu_init() (Book3s PR 64-bit) - kvmppc_mmu_destroy_e500() which does nothing (BookE e500/e500mc) It turns out that this is only relevant to PR KVM actually. And both 32 and 64 backends need vcpu->arch.book3s to be valid when calling kvmppc_mmu_destroy_pr(). So instead of calling kvmppc_mmu_destroy() from kvm_arch_vcpu_destroy(), call kvmppc_mmu_destroy_pr() at the beginning of kvmppc_core_vcpu_free_pr(). This is consistent with kvmppc_mmu_init() being the last call in kvmppc_core_vcpu_create_pr(). For the same reason, if kvmppc_core_vcpu_create_pr() returns an error then this means that kvmppc_mmu_init() was either not called or failed, in which case kvmppc_mmu_destroy() should not be called. Drop the line in the error path of kvm_arch_vcpu_create(). Fixes: ff030fdf5573 ("KVM: PPC: Move kvm_vcpu_init() invocation to common code") Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-03-19KVM: PPC: Use fallthrough;Joe Perches
Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe.com/ Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-03-16KVM: Remove unnecessary asm/kvm_host.h includesPeter Xu
Remove includes of asm/kvm_host.h from files that already include linux/kvm_host.h to make it more obvious that there is no ordering issue between the two headers. linux/kvm_host.h includes asm/kvm_host.h to pick up architecture specific settings, and this will never change, i.e. including asm/kvm_host.h after linux/kvm_host.h may seem problematic, but in practice is simply redundant. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16KVM: Simplify kvm_free_memslot() and all its descendentsSean Christopherson
Now that all callers of kvm_free_memslot() pass NULL for @dont, remove the param from the top-level routine and all arch's implementations. No functional change intended. Tested-by: Christoffer Dall <christoffer.dall@arm.com> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16KVM: Drop "const" attribute from old memslot in commit_memory_region()Sean Christopherson
Drop the "const" attribute from @old in kvm_arch_commit_memory_region() to allow arch specific code to free arch specific resources in the old memslot without having to cast away the attribute. Freeing resources in kvm_arch_commit_memory_region() paves the way for simplifying kvm_free_memslot() by eliminating the last usage of its @dont param. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16KVM: Drop kvm_arch_create_memslot()Sean Christopherson
Remove kvm_arch_create_memslot() now that all arch implementations are effectively nops. Removing kvm_arch_create_memslot() eliminates the possibility for arch specific code to allocate memory prior to setting a memslot, which sets the stage for simplifying kvm_free_memslot(). Cc: Janosch Frank <frankja@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16KVM: PPC: Move memslot memory allocation into prepare_memory_region()Sean Christopherson
Allocate the rmap array during kvm_arch_prepare_memory_region() to pave the way for removing kvm_arch_create_memslot() altogether. Moving PPC's memory allocation only changes the order of kernel memory allocations between PPC and common KVM code. No functional change intended. Acked-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27KVM: Drop kvm_arch_vcpu_init() and kvm_arch_vcpu_uninit()Sean Christopherson
Remove kvm_arch_vcpu_init() and kvm_arch_vcpu_uninit() now that all arch specific implementations are nops. Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27KVM: PPC: Move all vcpu init code into kvm_arch_vcpu_create()Sean Christopherson
Fold init() into create() now that the two are called back-to-back by common KVM code (kvm_vcpu_init() calls kvm_arch_vcpu_init() as its last action, and kvm_vm_ioctl_create_vcpu() calls kvm_arch_vcpu_create() immediately thereafter). Rinse and repeat for kvm_arch_vcpu_uninit() and kvm_arch_vcpu_destroy(). This paves the way for removing kvm_arch_vcpu_{un}init() entirely. Note, calling kvmppc_mmu_destroy() if kvmppc_core_vcpu_create() fails may or may not be necessary. Move it along with the more obvious call to kvmppc_subarch_vcpu_uninit() so as not to inadvertantly introduce a functional change and/or bug. No functional change intended. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27KVM: Move vcpu alloc and init invocation to common codeSean Christopherson
Now that all architectures tightly couple vcpu allocation/free with the mandatory calls to kvm_{un}init_vcpu(), move the sequences verbatim to common KVM code. Move both allocation and initialization in a single patch to eliminate thrash in arch specific code. The bisection benefits of moving the two pieces in separate patches is marginal at best, whereas the odds of introducing a transient arch specific bug are non-zero. Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24KVM: Introduce kvm_vcpu_destroy()Sean Christopherson
Add kvm_vcpu_destroy() and wire up all architectures to call the common function instead of their arch specific implementation. The common destruction function will be used by future patches to move allocation and initialization of vCPUs to common KVM code, i.e. to free resources that are allocated by arch agnostic code. No functional change intended. Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24KVM: Add kvm_arch_vcpu_precreate() to handle pre-allocation issuesSean Christopherson
Add a pre-allocation arch hook to handle checks that are currently done by arch specific code prior to allocating the vCPU object. This paves the way for moving the allocation to common KVM code. Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24KVM: PPC: Drop kvm_arch_vcpu_free()Sean Christopherson
Remove the superfluous kvm_arch_vcpu_free() as it is no longer called from commmon KVM code. Note, kvm_arch_vcpu_destroy() *is* called from common code, i.e. choosing which function to whack is not completely arbitrary. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24KVM: PPC: Move kvm_vcpu_init() invocation to common codeSean Christopherson
Move the kvm_cpu_{un}init() calls to common PPC code as an intermediate step towards removing kvm_cpu_{un}init() altogether. No functional change intended. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24KVM: PPC: Allocate vcpu struct in common PPC codeSean Christopherson
Move allocation of all flavors of PPC vCPUs to common PPC code. All variants either allocate 'struct kvm_vcpu' directly, or require that the embedded 'struct kvm_vcpu' member be located at offset 0, i.e. guarantee that the allocation can be directly interpreted as a 'struct kvm_vcpu' object. Remove the message from the build-time assertion regarding placement of the struct, as compatibility with the arch usercopy region is no longer the sole dependent on 'struct kvm_vcpu' being at offset zero. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-28KVM: PPC: Book3S HV: Support reset of secure guestBharata B Rao
Add support for reset of secure guest via a new ioctl KVM_PPC_SVM_OFF. This ioctl will be issued by QEMU during reset and includes the the following steps: - Release all device pages of the secure guest. - Ask UV to terminate the guest via UV_SVM_TERMINATE ucall - Unpin the VPA pages so that they can be migrated back to secure side when guest becomes secure again. This is required because pinned pages can't be migrated. - Reinit the partition scoped page tables After these steps, guest is ready to issue UV_ESM call once again to switch to secure mode. Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> [Implementation of uv_svm_terminate() and its call from guest shutdown path] Signed-off-by: Ram Pai <linuxram@us.ibm.com> [Unpinning of VPA pages] Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-10-21KVM: PPC: Report single stepping capabilityFabiano Rosas
When calling the KVM_SET_GUEST_DEBUG ioctl, userspace might request the next instruction to be single stepped via the KVM_GUESTDBG_SINGLESTEP control bit of the kvm_guest_debug structure. This patch adds the KVM_CAP_PPC_GUEST_DEBUG_SSTEP capability in order to inform userspace about the state of single stepping support. We currently don't have support for guest single stepping implemented in Book3S HV so the capability is only present for Book3S PR and BookE. Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-09-10Merge tag 'kvm-ppc-next-5.4-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD PPC KVM update for 5.4 - Some prep for extending the uses of the rmap array - Various minor fixes - Commits from the powerpc topic/ppc-kvm branch, which fix a problem with interrupts arriving after free_irq, causing host hangs and crashes.
2019-08-27KVM: PPC: Book3S: Enable XIVE native capability only if OPAL has required ↵Paul Mackerras
functions There are some POWER9 machines where the OPAL firmware does not support the OPAL_XIVE_GET_QUEUE_STATE and OPAL_XIVE_SET_QUEUE_STATE calls. The impact of this is that a guest using XIVE natively will not be able to be migrated successfully. On the source side, the get_attr operation on the KVM native device for the KVM_DEV_XIVE_GRP_EQ_CONFIG attribute will fail; on the destination side, the set_attr operation for the same attribute will fail. This adds tests for the existence of the OPAL get/set queue state functions, and if they are not supported, the XIVE-native KVM device is not created and the KVM_CAP_PPC_IRQ_XIVE capability returns false. Userspace can then either provide a software emulation of XIVE, or else tell the guest that it does not have a XIVE controller available to it. Cc: stable@vger.kernel.org # v5.2+ Fixes: 3fab2d10588e ("KVM: PPC: Book3S HV: XIVE: Activate XIVE exploitation mode") Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-08-05KVM: remove kvm_arch_has_vcpu_debugfs()Paolo Bonzini
There is no need for this function as all arches have to implement kvm_arch_create_vcpu_debugfs() no matter what. A #define symbol let us actually simplify the code. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-05KVM: Fix leak vCPU's VMCS value into other pCPUWanpeng Li
After commit d73eb57b80b (KVM: Boost vCPUs that are delivering interrupts), a five years old bug is exposed. Running ebizzy benchmark in three 80 vCPUs VMs on one 80 pCPUs Skylake server, a lot of rcu_sched stall warning splatting in the VMs after stress testing: INFO: rcu_sched detected stalls on CPUs/tasks: { 4 41 57 62 77} (detected by 15, t=60004 jiffies, g=899, c=898, q=15073) Call Trace: flush_tlb_mm_range+0x68/0x140 tlb_flush_mmu.part.75+0x37/0xe0 tlb_finish_mmu+0x55/0x60 zap_page_range+0x142/0x190 SyS_madvise+0x3cd/0x9c0 system_call_fastpath+0x1c/0x21 swait_active() sustains to be true before finish_swait() is called in kvm_vcpu_block(), voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin() loop greatly increases the probability condition kvm_arch_vcpu_runnable(vcpu) is checked and can be true, when APICv is enabled the yield-candidate vCPU's VMCS RVI field leaks(by vmx_sync_pir_to_irr()) into spinning-on-a-taken-lock vCPU's current VMCS. This patch fixes it by checking conservatively a subset of events. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Marc Zyngier <Marc.Zyngier@arm.com> Cc: stable@vger.kernel.org Fixes: 98f4a1467 (KVM: add kvm_arch_vcpu_runnable() test to kvm_vcpu_on_spin() loop) Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-11Merge tag 'kvm-arm-for-5.3' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for 5.3 - Add support for chained PMU counters in guests - Improve SError handling - Handle Neoverse N1 erratum #1349291 - Allow side-channel mitigation status to be migrated - Standardise most AArch64 system register accesses to msr_s/mrs_s - Fix host MPIDR corruption on 32bit
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 67 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141333.953658117@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>