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2023-07-01Merge tag 'kvmarm-6.5' of ↵Paolo Bonzini1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 6.5 - Eager page splitting optimization for dirty logging, optionally allowing for a VM to avoid the cost of block splitting in the stage-2 fault path. - Arm FF-A proxy for pKVM, allowing a pKVM host to safely interact with services that live in the Secure world. pKVM intervenes on FF-A calls to guarantee the host doesn't misuse memory donated to the hyp or a pKVM guest. - Support for running the split hypervisor with VHE enabled, known as 'hVHE' mode. This is extremely useful for testing the split hypervisor on VHE-only systems, and paves the way for new use cases that depend on having two TTBRs available at EL2. - Generalized framework for configurable ID registers from userspace. KVM/arm64 currently prevents arbitrary CPU feature set configuration from userspace, but the intent is to relax this limitation and allow userspace to select a feature set consistent with the CPU. - Enable the use of Branch Target Identification (FEAT_BTI) in the hypervisor. - Use a separate set of pointer authentication keys for the hypervisor when running in protected mode, as the host is untrusted at runtime. - Ensure timer IRQs are consistently released in the init failure paths. - Avoid trapping CTR_EL0 on systems with Enhanced Virtualization Traps (FEAT_EVT), as it is a register commonly read from userspace. - Erratum workaround for the upcoming AmpereOne part, which has broken hardware A/D state management. As a consequence of the hVHE series reworking the arm64 software features framework, the for-next/module-alloc branch from the arm64 tree comes along for the ride.
2023-06-13KVM: arm64: Rework CPTR_EL2 programming for HVHE configurationMarc Zyngier1-1/+1
Just like we repainted the early arm64 code, we need to update the CPTR_EL2 accesses that are taking place in the nVHE code when hVHE is used, making them look as if they were CPACR_EL1 accesses. Just like the VHE code. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230609162200.2024064-14-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-04KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loadedReiji Watanabe1-0/+14
Currently, with VHE, KVM sets ER, CR, SW and EN bits of PMUSERENR_EL0 to 1 on vcpu_load(), and saves and restores the register value for the host on vcpu_load() and vcpu_put(). If the value of those bits are cleared on a pCPU with a vCPU loaded (armv8pmu_start() would do that when PMU counters are programmed for the guest), PMU access from the guest EL0 might be trapped to the guest EL1 directly regardless of the current PMUSERENR_EL0 value of the vCPU. Fix this by not letting armv8pmu_start() overwrite PMUSERENR_EL0 on the pCPU where PMUSERENR_EL0 for the guest is loaded, and instead updating the saved shadow register value for the host so that the value can be restored on vcpu_put() later. While vcpu_{put,load}() are manipulating PMUSERENR_EL0, disable IRQs to prevent a race condition between these processes and IPIs that attempt to update PMUSERENR_EL0 for the host EL0. Suggested-by: Mark Rutland <mark.rutland@arm.com> Suggested-by: Marc Zyngier <maz@kernel.org> Fixes: 83a7a4d643d3 ("arm64: perf: Enable PMU counter userspace access for perf event") Signed-off-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230603025035.3781797-3-reijiw@google.com
2023-05-30KVM: arm64: Populate fault info for watchpointAkihiko Odaki1-0/+1
When handling ESR_ELx_EC_WATCHPT_LOW, far_el2 member of struct kvm_vcpu_fault_info will be copied to far member of struct kvm_debug_exit_arch and exposed to the userspace. The userspace will see stale values from older faults if the fault info does not get populated. Fixes: 8fb2046180a0 ("KVM: arm64: Move early handlers to per-EC handlers") Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230530024651.10014-1-akihiko.odaki@daynix.com Cc: stable@vger.kernel.org
2023-04-14KVM: arm64: vhe: Drop extra isb() on guest exitMarc Zyngier1-4/+3
__kvm_vcpu_run_vhe() end on VHE with an isb(). However, this function is only reachable via kvm_call_hyp_ret(), which already contains an isb() in order to mimick the behaviour of nVHE and provide a context synchronisation event. We thus have two isb()s back to back, which is one too many. Drop the first one and solely rely on the one in the helper. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-14Merge branch kvm-arm64/nv-prefix into kvmarm/nextOliver Upton1-0/+24
* kvm-arm64/nv-prefix: : Preamble to NV support, courtesy of Marc Zyngier. : : This brings in a set of prerequisite patches for supporting nested : virtualization in KVM/arm64. Of course, there is a long way to go until : NV is actually enabled in KVM. : : - Introduce cpucap / vCPU feature flag to pivot the NV code on : : - Add support for EL2 vCPU register state : : - Basic nested exception handling : : - Hide unsupported features from the ID registers for NV-capable VMs KVM: arm64: nv: Use reg_to_encoding() to get sysreg ID KVM: arm64: nv: Only toggle cache for virtual EL2 when SCTLR_EL2 changes KVM: arm64: nv: Filter out unsupported features from ID regs KVM: arm64: nv: Emulate EL12 register accesses from the virtual EL2 KVM: arm64: nv: Allow a sysreg to be hidden from userspace only KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisor KVM: arm64: nv: Add accessors for SPSR_EL1, ELR_EL1 and VBAR_EL1 from virtual EL2 KVM: arm64: nv: Handle SMCs taken from virtual EL2 KVM: arm64: nv: Handle trapped ERET from virtual EL2 KVM: arm64: nv: Inject HVC exceptions to the virtual EL2 KVM: arm64: nv: Support virtual EL2 exceptions KVM: arm64: nv: Handle HCR_EL2.NV system register traps KVM: arm64: nv: Add nested virt VCPU primitives for vEL2 VCPU state KVM: arm64: nv: Add EL2 system registers to vcpu context KVM: arm64: nv: Allow userspace to set PSR_MODE_EL2x KVM: arm64: nv: Reset VCPU to EL2 registers if VCPU nested virt is set KVM: arm64: nv: Introduce nested virtualization VCPU feature KVM: arm64: Use the S2 MMU context to iterate over S2 table arm64: Add ARM64_HAS_NESTED_VIRT cpufeature Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-11KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisorMarc Zyngier1-0/+24
We can no longer blindly copy the VCPU's PSTATE into SPSR_EL2 and return to the guest and vice versa when taking an exception to the hypervisor, because we emulate virtual EL2 in EL1 and therefore have to translate the mode field from EL2 to EL1 and vice versa. This requires keeping track of the state we enter the guest, for which we transiently use a dedicated flag. Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230209175820.1939006-15-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-01-13KVM: arm64: Kill CPACR_EL1_TTA definitionMarc Zyngier1-1/+1
Since the One True Way is to use the new generated definition, kill the KVM-specific definition of CPACR_EL1_TTA, and move over to CPACR_ELx_TTA, hopefully for the same result. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230112154803.1808559-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2022-11-01KVM: arm64: Fix SMPRI_EL1/TPIDR2_EL0 trapping on VHEMarc Zyngier1-8/+0
The trapping of SMPRI_EL1 and TPIDR2_EL0 currently only really work on nVHE, as only this mode uses the fine-grained trapping that controls these two registers. Move the trapping enable/disable code into __{de,}activate_traps_common(), allowing it to be called when it actually matters on VHE, and remove the flipping of EL2 control for TPIDR2_EL0, which only affects the host access of this register. Fixes: 861262ab8627 ("KVM: arm64: Handle SME host state when running guests") Reported-by: Mark Brown <broonie@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/86bkpqer4z.wl-maz@kernel.org
2022-07-17Merge branch kvm-arm64/misc-5.20 into kvmarm-master/nextMarc Zyngier1-1/+1
* kvm-arm64/misc-5.20: : . : Misc fixes for 5.20: : : - Tidy up the hyp/nvhe Makefile : : - Fix functions pointlessly returning a void value : : - Fix vgic_init selftest to handle the GICv3-on-v3 case : : - Fix hypervisor symbolisation when CONFIG_RANDOMIZE_BASE=y : . KVM: arm64: Fix hypervisor address symbolization KVM: arm64: selftests: Add support for GICv2 on v3 KVM: arm64: Don't return from void function KVM: arm64: nvhe: Add intermediates to 'targets' instead of extra-y KVM: arm64: nvhe: Rename confusing obj-y Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-07-06KVM: arm64: Don't return from void functionQuentin Perret1-1/+1
Although harmless, the return statement in kvm_unexpected_el2_exception is rather confusing as the function itself has a void return type. The C standard is also pretty clear that "A return statement with an expression shall not appear in a function whose return type is void". Given that this return statement does not seem to add any actual value, let's not pointlessly violate the standard. Build-tested with GCC 10 and CLANG 13 for good measure, the disassembled code is identical with or without the return statement. Fixes: e9ee186bb735 ("KVM: arm64: Add kvm_extable for vaxorcism code") Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220705142310.3847918-1-qperret@google.com
2022-06-09KVM: arm64: Move FP state ownership from flag to a tristateMarc Zyngier1-1/+1
The KVM FP code uses a pair of flags to denote three states: - FP_ENABLED set: the guest owns the FP state - FP_HOST set: the host owns the FP state - FP_ENABLED and FP_HOST clear: nobody owns the FP state at all and both flags set is an illegal state, which nothing ever checks for... As it turns out, this isn't really a good match for flags, and we'd be better off if this was a simpler tristate, each state having a name that actually reflect the state: - FP_STATE_FREE - FP_STATE_HOST_OWNED - FP_STATE_GUEST_OWNED Kill the two flags, and move over to an enum encoding these three states. This results in less confusing code, and less risk of ending up in the uncharted territory of a 4th state if we forget to clear one of the two flags. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Reiji Watanabe <reijiw@google.com>
2022-06-09KVM: arm64: Drop FP_FOREIGN_STATE from the hypervisor codeMarc Zyngier1-1/+1
The vcpu KVM_ARM64_FP_FOREIGN_FPSTATE flag tracks the thread's own TIF_FOREIGN_FPSTATE so that we can evaluate just before running the vcpu whether it the FP regs contain something that is owned by the vcpu or not by updating the rest of the FP flags. We do this in the hypervisor code in order to make sure we're in a context where we are not interruptible. But we already have a hook in the run loop to generate this flag. We may as well update the FP flags directly and save the pointless flag tracking. Whilst we're at it, rename update_fp_enabled() to guest_owns_fp_regs() to indicate what the leftover of this helper actually do. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Reiji Watanabe <reijiw@google.com> Reviewed-by: Mark Brown <broonie@kernel.org>
2022-04-22KVM: arm64: Trap SME usage in guestMark Brown1-1/+10
SME defines two new traps which need to be enabled for guests to ensure that they can't use SME, one for the main SME operations which mirrors the traps for SVE and another for access to TPIDR2 in SCTLR_EL2. For VHE manage SMEN along with ZEN in activate_traps() and the FP state management callbacks, along with SCTLR_EL2.EnTPIDR2. There is no existing dynamic management of SCTLR_EL2. For nVHE manage TSM in activate_traps() along with the fine grained traps for TPIDR2 and SMPRI. There is no existing dynamic management of fine grained traps. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220419112247.711548-26-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-03-14Merge branch 'for-next/spectre-bhb' into for-next/coreWill Deacon1-2/+8
Merge in the latest Spectre mess to fix up conflicts with what was already queued for 5.18 when the embargo finally lifted. * for-next/spectre-bhb: (21 commits) arm64: Do not include __READ_ONCE() block in assembly files arm64: proton-pack: Include unprivileged eBPF status in Spectre v2 mitigation reporting arm64: Use the clearbhb instruction in mitigations KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated arm64: Mitigate spectre style branch history side channels arm64: proton-pack: Report Spectre-BHB vulnerabilities as part of Spectre-v2 arm64: Add percpu vectors for EL1 arm64: entry: Add macro for reading symbol addresses from the trampoline arm64: entry: Add vectors that have the bhb mitigation sequences arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations arm64: entry: Allow the trampoline text to occupy multiple pages arm64: entry: Make the kpti trampoline's kpti sequence optional arm64: entry: Move trampoline macros out of ifdef'd section arm64: entry: Don't assume tramp_vectors is the start of the vectors arm64: entry: Allow tramp_alias to access symbols after the 4K boundary arm64: entry: Move the trampoline data page before the text page arm64: entry: Free up another register on kpti's tramp_exit path arm64: entry: Make the trampoline cleanup optional KVM: arm64: Allow indirect vectors to be used without SPECTRE_V3A arm64: spectre: Rename spectre_v4_patch_fw_mitigation_conduit ...
2022-02-25arm64: Always use individual bits in CPACR floating point enablesMark Brown1-3/+3
CPACR_EL1 has several bitfields for controlling traps for floating point features to EL1, each of which has a separate bits for EL0 and EL1. Marc Zyngier noted that we are not consistent in our use of defines to manipulate these, sometimes using a define covering the whole field and sometimes using defines for the individual bits. Make this consistent by expanding the whole field defines where they are used (currently only in the KVM code) and deleting them so that no further uses can be introduced. Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20220207152109.197566-3-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2022-02-16arm64: Add percpu vectors for EL1James Morse1-2/+8
The Spectre-BHB workaround adds a firmware call to the vectors. This is needed on some CPUs, but not others. To avoid the unaffected CPU in a big/little pair from making the firmware call, create per cpu vectors. The per-cpu vectors only apply when returning from EL0. Systems using KPTI can use the canonical 'full-fat' vectors directly at EL1, the trampoline exit code will switch to this_cpu_vector on exit to EL0. Systems not using KPTI should always use this_cpu_vector. this_cpu_vector will point at a vector in tramp_vecs or __bp_harden_el1_vectors, depending on whether KPTI is in use. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: James Morse <james.morse@arm.com>
2022-01-07Merge tag 'kvmarm-5.17' of ↵Paolo Bonzini1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 5.16 - 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
2021-11-24KVM: arm64: Move pkvm's special 32bit handling into a generic infrastructureMarc Zyngier1-0/+4
Protected KVM is trying to turn AArch32 exceptions into an illegal exception entry. Unfortunately, it does that in a way that is a bit abrupt, and too early for PSTATE to be available. Instead, move it to the fixup code, which is a more reasonable place for it. This will also be useful for the NV code. Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-11-22KVM: arm64: Stop mapping current thread_info at EL2Marc Zyngier1-1/+0
Now that we can track an equivalent of TIF_FOREIGN_FPSTATE, drop the mapping of current's thread_info at EL2. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-10-18KVM: arm64: pkvm: Pass vpcu instead of kvm to kvm_get_exit_handler_array()Marc Zyngier1-1/+1
Passing a VM pointer around is odd, and results in extra work on VHE. Follow the rest of the design that uses the vcpu instead, and let the nVHE code look into the struct kvm as required. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20211013120346.2926621-11-maz@kernel.org
2021-10-11KVM: arm64: Pass struct kvm to per-EC handlersFuad Tabba1-1/+1
We need struct kvm to check for protected VMs to be able to pick the right handlers for them in subsequent patches. Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211010145636.1950948-5-tabba@google.com
2021-10-11KVM: arm64: Move early handlers to per-EC handlersMarc Zyngier1-0/+16
Simplify the early exception handling by slicing the gigantic decoding tree into a more manageable set of functions, similar to what we have in handle_exit.c. This will also make the structure reusable for pKVM's own early exit handling. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20211010145636.1950948-4-tabba@google.com
2021-08-20Merge branch kvm-arm64/pkvm-fixed-features-prologue into kvmarm-master/nextMarc Zyngier1-10/+2
* kvm-arm64/pkvm-fixed-features-prologue: : Rework a bunch of common infrastructure as a prologue : to Fuad Tabba's protected VM fixed feature series. KVM: arm64: Upgrade trace_kvm_arm_set_dreg32() to 64bit KVM: arm64: Add config register bit definitions KVM: arm64: Add feature register flag definitions KVM: arm64: Track value of cptr_el2 in struct kvm_vcpu_arch KVM: arm64: Keep mdcr_el2's value as set by __init_el2_debug KVM: arm64: Restore mdcr_el2 from vcpu KVM: arm64: Refactor sys_regs.h,c for nVHE reuse KVM: arm64: Fix names of config register fields KVM: arm64: MDCR_EL2 is a 64-bit register KVM: arm64: Remove trailing whitespace in comment KVM: arm64: placeholder to check if VM is protected Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-08-20KVM: arm64: Keep mdcr_el2's value as set by __init_el2_debugFuad Tabba1-4/+0
__init_el2_debug configures mdcr_el2 at initialization based on, among other things, available hardware support. Trap deactivation doesn't check that, so keep the initial value. No functional change intended. Signed-off-by: Fuad Tabba <tabba@google.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210817081134.2918285-8-tabba@google.com
2021-08-20KVM: arm64: Restore mdcr_el2 from vcpuFuad Tabba1-9/+5
On deactivating traps, restore the value of mdcr_el2 from the newly created and preserved host value vcpu context, rather than directly reading the hardware register. Up until and including this patch the two values are the same, i.e., the hardware register and the vcpu one. A future patch will be changing the value of mdcr_el2 on activating traps, and this ensures that its value will be restored. No functional change intended. Signed-off-by: Fuad Tabba <tabba@google.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210817081134.2918285-7-tabba@google.com
2021-08-20KVM: arm64: Unify stage-2 programming behind __load_stage2()Marc Zyngier1-3/+3
The protected mode relies on a separate helper to load the S2 context. Move over to the __load_guest_stage2() helper instead, and rename it to __load_stage2() to present a unified interface. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Jade Alglave <jade.alglave@arm.com> Cc: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210806113109.2475-5-will@kernel.org
2021-08-20KVM: arm64: Move kern_hyp_va() usage in __load_guest_stage2() into the callersMarc Zyngier1-1/+1
It is a bit awkward to use kern_hyp_va() in __load_guest_stage2(), specially as the helper is shared between VHE and nVHE. Instead, move the use of kern_hyp_va() in the nVHE code, and pass a pointer to the kvm->arch structure instead. Although this may look a bit awkward, it allows for some further simplification. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Jade Alglave <jade.alglave@arm.com> Cc: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210806113109.2475-4-will@kernel.org
2021-05-15KVM: arm64: Move __adjust_pc out of lineMarc Zyngier1-2/+1
In order to make it easy to call __adjust_pc() from the EL1 code (in the case of nVHE), rename it to __kvm_adjust_pc() and move it out of line. No expected functional change. Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Tested-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org # 5.11
2021-04-01KVM: arm64: Log source when panicking from nVHE hypAndrew Scull1-3/+1
To aid with debugging, add details of the source of a panic from nVHE hyp. This is done by having nVHE hyp exit to nvhe_hyp_panic_handler() rather than directly to panic(). The handler will then add the extra details for debugging before panicking the kernel. If the panic was due to a BUG(), look up the metadata to log the file and line, if available, otherwise log an address that can be looked up in vmlinux. The hyp offset is also logged to allow other hyp VAs to be converted, similar to how the kernel offset is logged during a panic. __hyp_panic_string is now inlined since it no longer needs to be referenced as a symbol and the message is free to diverge between VHE and nVHE. The following is an example of the logs generated by a BUG in nVHE hyp. [ 46.754840] kvm [307]: nVHE hyp BUG at: arch/arm64/kvm/hyp/nvhe/switch.c:242! [ 46.755357] kvm [307]: Hyp Offset: 0xfffea6c58e1e0000 [ 46.755824] Kernel panic - not syncing: HYP panic: [ 46.755824] PS:400003c9 PC:0000d93a82c705ac ESR:f2000800 [ 46.755824] FAR:0000000080080000 HPFAR:0000000000800800 PAR:0000000000000000 [ 46.755824] VCPU:0000d93a880d0000 [ 46.756960] CPU: 3 PID: 307 Comm: kvm-vcpu-0 Not tainted 5.12.0-rc3-00005-gc572b99cf65b-dirty #133 [ 46.757459] Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 [ 46.758366] Call trace: [ 46.758601] dump_backtrace+0x0/0x1b0 [ 46.758856] show_stack+0x18/0x70 [ 46.759057] dump_stack+0xd0/0x12c [ 46.759236] panic+0x16c/0x334 [ 46.759426] arm64_kernel_unmapped_at_el0+0x0/0x30 [ 46.759661] kvm_arch_vcpu_ioctl_run+0x134/0x750 [ 46.759936] kvm_vcpu_ioctl+0x2f0/0x970 [ 46.760156] __arm64_sys_ioctl+0xa8/0xec [ 46.760379] el0_svc_common.constprop.0+0x60/0x120 [ 46.760627] do_el0_svc+0x24/0x90 [ 46.760766] el0_svc+0x2c/0x54 [ 46.760915] el0_sync_handler+0x1a4/0x1b0 [ 46.761146] el0_sync+0x170/0x180 [ 46.761889] SMP: stopping secondary CPUs [ 46.762786] Kernel Offset: 0x3e1cd2820000 from 0xffff800010000000 [ 46.763142] PHYS_OFFSET: 0xffffa9f680000000 [ 46.763359] CPU features: 0x00240022,61806008 [ 46.763651] Memory Limit: none [ 46.813867] ---[ end Kernel panic - not syncing: HYP panic: [ 46.813867] PS:400003c9 PC:0000d93a82c705ac ESR:f2000800 [ 46.813867] FAR:0000000080080000 HPFAR:0000000000800800 PAR:0000000000000000 [ 46.813867] VCPU:0000d93a880d0000 ]--- Signed-off-by: Andrew Scull <ascull@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210318143311.839894-6-ascull@google.com
2020-11-10KVM: arm64: Make kvm_skip_instr() and co private to HYPMarc Zyngier1-0/+3
In an effort to remove the vcpu PC manipulations from EL1 on nVHE systems, move kvm_skip_instr() to be HYP-specific. EL1's intent to increment PC post emulation is now signalled via a flag in the vcpu structure. Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-10-29arm64: Add workaround for Arm Cortex-A77 erratum 1508412Rob Herring1-1/+1
On Cortex-A77 r0p0 and r1p0, a sequence of a non-cacheable or device load and a store exclusive or PAR_EL1 read can cause a deadlock. The workaround requires a DMB SY before and after a PAR_EL1 register read. In addition, it's possible an interrupt (doing a device read) or KVM guest exit could be taken between the DMB and PAR read, so we also need a DMB before returning from interrupt and before returning to a guest. A deadlock is still possible with the workaround as KVM guests must also have the workaround. IOW, a malicious guest can deadlock an affected systems. This workaround also depends on a firmware counterpart to enable the h/w to insert DMB SY after load and store exclusive instructions. See the errata document SDEN-1152370 v10 [1] for more information. [1] https://static.docs.arm.com/101992/0010/Arm_Cortex_A77_MP074_Software_Developer_Errata_Notice_v10.pdf Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Julien Thierry <julien.thierry.kdev@gmail.com> Cc: kvmarm@lists.cs.columbia.edu Link: https://lore.kernel.org/r/20201028182839.166037-2-robh@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2020-09-30Merge branch 'kvm-arm64/hyp-pcpu' into kvmarm-master/nextMarc Zyngier1-6/+7
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-09-30Merge remote-tracking branch 'arm64/for-next/ghostbusters' into ↵Marc Zyngier1-4/+0
kvm-arm64/hyp-pcpu Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-09-30kvm: arm64: Create separate instances of kvm_host_data for VHE/nVHEDavid Brazdil1-0/+3
Host CPU context is stored in a global per-cpu variable `kvm_host_data`. In preparation for introducing independent per-CPU region for nVHE hyp, create two separate instances of `kvm_host_data`, one for VHE and one for nVHE. Signed-off-by: David Brazdil <dbrazdil@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20200922204910.7265-9-dbrazdil@google.com
2020-09-30kvm: arm64: Remove __hyp_this_cpu_readDavid Brazdil1-1/+1
this_cpu_ptr is meant for use in kernel proper because it selects between TPIDR_EL1/2 based on nVHE/VHE. __hyp_this_cpu_ptr was used in hyp to always select TPIDR_EL2. Unify all users behind this_cpu_ptr and friends by selecting _EL2 register under __KVM_NVHE_HYPERVISOR__. VHE continues selecting the register using alternatives. Under CONFIG_DEBUG_PREEMPT, the kernel helpers perform a preemption check which is omitted by the hyp helpers. Preserve the behavior for nVHE by overriding the corresponding macros under __KVM_NVHE_HYPERVISOR__. Extend the checks into VHE hyp code. Signed-off-by: David Brazdil <dbrazdil@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Andrew Scull <ascull@google.com> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20200922204910.7265-5-dbrazdil@google.com
2020-09-29KVM: arm64: Simplify handling of ARCH_WORKAROUND_2Marc Zyngier1-4/+0
Owing to the fact that the host kernel is always mitigated, we can drastically simplify the WA2 handling by keeping the mitigation state ON when entering the guest. This means the guest is either unaffected or not mitigated. This results in a nice simplification of the mitigation space, and the removal of a lot of code that was never really used anyway. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2020-09-15KVM: arm64: Introduce hyp contextAndrew Scull1-1/+1
During __guest_enter, save and restore from a new hyp context rather than the host context. This is preparation for separation of the hyp and host context in nVHE. Signed-off-by: Andrew Scull <ascull@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200915104643.2543892-9-ascull@google.com
2020-09-15KVM: arm64: Save chosen hyp vector to a percpu variableAndrew Scull1-1/+1
Introduce a percpu variable to hold the address of the selected hyp vector that will be used with guests. This avoids the selection process each time a guest is being entered and can be used by nVHE when a separate vector is introduced for the host. Signed-off-by: Andrew Scull <ascull@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200915104643.2543892-6-ascull@google.com
2020-09-15KVM: arm64: Remove hyp_panic argumentsAndrew Scull1-4/+6
hyp_panic is able to find all the context it needs from within itself so remove the argument. The __hyp_panic wrapper becomes redundant so is also removed. Signed-off-by: Andrew Scull <ascull@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200915104643.2543892-3-ascull@google.com
2020-09-15KVM: arm64: Remove __activate_vm wrapperAndrew Scull1-5/+5
The __activate_vm wrapper serves no useful function and has a misleading name as it simply calls __load_guest_stage2 and does not touch HCR_EL2.VM so remove it. Also rename __deactivate_vm to __load_host_stage2 to match naming pattern. Signed-off-by: Andrew Scull <ascull@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200915104643.2543892-2-ascull@google.com
2020-08-28KVM: arm64: Add kvm_extable for vaxorcism codeJames Morse1-0/+5
KVM has a one instruction window where it will allow an SError exception to be consumed by the hypervisor without treating it as a hypervisor bug. This is used to consume asynchronous external abort that were caused by the guest. As we are about to add another location that survives unexpected exceptions, generalise this code to make it behave like the host's extable. KVM's version has to be mapped to EL2 to be accessible on nVHE systems. The SError vaxorcism code is a one instruction window, so has two entries in the extable. Because the KVM code is copied for VHE and nVHE, we end up with four entries, half of which correspond with code that isn't mapped. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-07KVM: arm64: Factor out stage 2 page table data from struct kvmChristoffer Dall1-1/+1
As we are about to reuse our stage 2 page table manipulation code for shadow stage 2 page tables in the context of nested virtualization, we are going to manage multiple stage 2 page tables for a single VM. This requires some pretty invasive changes to our data structures, which moves the vmid and pgd pointers into a separate structure and change pretty much all of our mmu code to operate on this structure instead. The new structure is called struct kvm_s2_mmu. There is no intended functional change by this patch alone. Reviewed-by: James Morse <james.morse@arm.com> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> [Designed data structure layout in collaboration] Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Co-developed-by: Marc Zyngier <maz@kernel.org> [maz: Moved the last_vcpu_ran down to the S2 MMU structure as well] Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-05KVM: arm64: Split hyp/sysreg-sr.c to VHE/nVHEDavid Brazdil1-1/+1
sysreg-sr.c contains KVM's code for saving/restoring system registers, with some code shared between VHE/nVHE. These common routines are moved to a header file, VHE-specific code is moved to vhe/sysreg-sr.c and nVHE-specific code to nvhe/sysreg-sr.c. Signed-off-by: David Brazdil <dbrazdil@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200625131420.71444-12-dbrazdil@google.com
2020-07-05KVM: arm64: Split hyp/switch.c to VHE/nVHEDavid Brazdil1-0/+219
switch.c implements context-switching for KVM, with large parts shared between VHE/nVHE. These common routines are moved to a header file, VHE-specific code is moved to vhe/switch.c and nVHE-specific code is moved to nvhe/switch.c. Previously __kvm_vcpu_run needed a different symbol name for VHE/nVHE. This is cleaned up and the caller in arm.c simplified. Signed-off-by: David Brazdil <dbrazdil@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200625131420.71444-10-dbrazdil@google.com