linux-dev/arch/powerpc/kvm/Kconfig, branch linus/master

KVM: PPC: Book3S PR: Disable SCV when AIL could be disabled

2022-03-08T02:13:58Z

PR KVM does not support running with AIL enabled, and SCV does is not supported with AIL disabled. Fix this by ensuring the SCV facility is disabled with FSCR while a CPU could be running with AIL=0. The PowerNV host supports disabling AIL on a per-CPU basis, so SCV just needs to be disabled when a vCPU is being run. The pSeries machine can only switch AIL on a system-wide basis, so it must disable SCV support at boot if the configuration can potentially run a PR KVM guest. Also ensure a the FSCR[SCV] bit can not be enabled when emulating mtFSCR for the guest. SCV is not emulated for the PR guest at the moment, this just fixes the host crashes. Alternatives considered and rejected: - SCV support can not be disabled by PR KVM after boot, because it is advertised to userspace with HWCAP. - AIL can not be disabled on a per-CPU basis. At least when running on pseries it is a per-LPAR setting. - Support for real-mode SCV vectors will not be added because they are at 0x17000 so making such a large fixed head space causes immediate value limits to be exceeded, requiring a lot rework and more code. - Disabling SCV for any PR KVM possible kernel will cause a slowdown when not using PR KVM. - A boot time option to disable SCV to use PR KVM is user-hostile. - System call instruction emulation for SCV facility unavailable instructions is too complex and old emulation code was subtly broken and removed. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Reviewed-by: Fabiano Rosas Link: https://lore.kernel.org/r/20220222064727.2314380-2-npiggin@gmail.com

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2022-01-16T14:15:14Z

Pull kvm updates from Paolo Bonzini: "RISCV: - Use common KVM implementation of MMU memory caches - SBI v0.2 support for Guest - Initial KVM selftests support - Fix to avoid spurious virtual interrupts after clearing hideleg CSR - Update email address for Anup and Atish ARM: - Simplification of the 'vcpu first run' by integrating it into KVM's 'pid change' flow - Refactoring of the FP and SVE state tracking, also leading to a simpler state and less shared data between EL1 and EL2 in the nVHE case - Tidy up the header file usage for the nvhe hyp object - New HYP unsharing mechanism, finally allowing pages to be unmapped from the Stage-1 EL2 page-tables - Various pKVM cleanups around refcounting and sharing - A couple of vgic fixes for bugs that would trigger once the vcpu xarray rework is merged, but not sooner - Add minimal support for ARMv8.7's PMU extension - Rework kvm_pgtable initialisation ahead of the NV work - New selftest for IRQ injection - Teach selftests about the lack of default IPA space and page sizes - Expand sysreg selftest to deal with Pointer Authentication - The usual bunch of cleanups and doc update s390: - fix sigp sense/start/stop/inconsistency - cleanups x86: - Clean up some function prototypes more - improved gfn_to_pfn_cache with proper invalidation, used by Xen emulation - add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery - completely remove potential TOC/TOU races in nested SVM consistency checks - update some PMCs on emulated instructions - Intel AMX support (joint work between Thomas and Intel) - large MMU cleanups - module parameter to disable PMU virtualization - cleanup register cache - first part of halt handling cleanups - Hyper-V enlightened MSR bitmap support for nested hypervisors Generic: - clean up Makefiles - introduce CONFIG_HAVE_KVM_DIRTY_RING - optimize memslot lookup using a tree - optimize vCPU array usage by converting to xarray" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (268 commits) x86/fpu: Fix inline prefix warnings selftest: kvm: Add amx selftest selftest: kvm: Move struct kvm_x86_state to header selftest: kvm: Reorder vcpu_load_state steps for AMX kvm: x86: Disable interception for IA32_XFD on demand x86/fpu: Provide fpu_sync_guest_vmexit_xfd_state() kvm: selftests: Add support for KVM_CAP_XSAVE2 kvm: x86: Add support for getting/setting expanded xstate buffer x86/fpu: Add uabi_size to guest_fpu kvm: x86: Add CPUID support for Intel AMX kvm: x86: Add XCR0 support for Intel AMX kvm: x86: Disable RDMSR interception of IA32_XFD_ERR kvm: x86: Emulate IA32_XFD_ERR for guest kvm: x86: Intercept #NM for saving IA32_XFD_ERR x86/fpu: Prepare xfd_err in struct fpu_guest kvm: x86: Add emulation for IA32_XFD x86/fpu: Provide fpu_update_guest_xfd() for IA32_XFD emulation kvm: x86: Enable dynamic xfeatures at KVM_SET_CPUID2 x86/fpu: Provide fpu_enable_guest_xfd_features() for KVM x86/fpu: Add guest support to xfd_enable_feature() ...

Merge branch 'topic/ppc-kvm' of https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux into HEAD

2021-12-19T14:27:21Z

Fix conflicts between memslot overhaul and commit 511d25d6b789f ("KVM: PPC: Book3S: Suppress warnings when allocating too big memory slots") from the powerpc tree.

powerpc/64s: Make hash MMU support configurable

2021-12-09T11:40:24Z

This adds Kconfig selection which allows 64s hash MMU support to be disabled. It can be disabled if radix support is enabled, the minimum supported CPU type is POWER9 (or higher), and KVM is not selected. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211201144153.2456614-17-npiggin@gmail.com

KVM: Use interval tree to do fast hva lookup in memslots

2021-12-08T09:24:32Z

The current memslots implementation only allows quick binary search by gfn, quick lookup by hva is not possible - the implementation has to do a linear scan of the whole memslots array, even though the operation being performed might apply just to a single memslot. This significantly hurts performance of per-hva operations with higher memslot counts. Since hva ranges can overlap between memslots an interval tree is needed for tracking them. [sean: handle interval tree updates in kvm_replace_memslot()] Signed-off-by: Maciej S. Szmigiero Message-Id:

KVM: PPC: Book3S HV: Don't always save PMU for guest capable of nesting

2021-11-24T10:08:57Z

Provide a config option that controls the workaround added by commit 63279eeb7f93 ("KVM: PPC: Book3S HV: Always save guest pmu for guest capable of nesting"). The option defaults to y for now, but is expected to go away within a few releases. Nested capable guests running with the earlier commit 178266389794 ("KVM: PPC: Book3S HV Nested: Reflect guest PMU in-use to L0 when guest SPRs are live") will now indicate the PMU in-use status of their guests, which means the parent does not need to unconditionally save the PMU for nested capable guests. After this latest round of performance optimisations, this option costs about 540 cycles or 10% entry/exit performance on a POWER9 nested-capable guest. Signed-off-by: Nicholas Piggin Reviewed-by: Fabiano Rosas References: 178266389794 ("KVM: PPC: Book3S HV Nested: Reflect guest PMU in-use to L0 when guest SPRs are live") Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211123095231.1036501-11-npiggin@gmail.com

powerpc/kvm: Remove obsolete and unneeded select

2021-08-20T02:37:18Z

Commit a278e7ea608b ("powerpc: Fix compile issue with force DAWR") selects the non-existing config PPC_DAWR_FORCE_ENABLE for config KVM_BOOK3S_64_HANDLER. As this commit also introduces a config PPC_DAWR and this config PPC_DAWR is selected with PPC if PPC64, there is no need for any further select in the KVM_BOOK3S_64_HANDLER. Remove an obsolete and unneeded select in config KVM_BOOK3S_64_HANDLER. The issue was identified with ./scripts/checkkconfigsymbols.py. Fixes: a278e7ea608b ("powerpc: Fix compile issue with force DAWR") Signed-off-by: Lukas Bulwahn Reviewed-by: Daniel Axtens Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210819113954.17515-2-lukas.bulwahn@gmail.com

powerpc/kvm: Force selection of CONFIG_PPC_FPU

2021-01-30T00:39:32Z

book3s/32 kvm is designed with the assumption that an FPU is always present. Force selection of FPU support in the kernel when build KVM. Fixes: 7d68c8916950 ("powerpc/32s: Allow deselecting CONFIG_PPC_FPU on mpc832x") Reported-by: kernel test robot Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/74461a99fa1466f361532ca794ca0753be3d9f86.1611038044.git.christophe.leroy@csgroup.eu

treewide: replace '---help---' in Kconfig files with 'help'

2020-06-13T16:57:21Z

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada

vhost: refine vhost and vringh kconfig

2020-04-01T16:06:26Z

Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin