summaryrefslogtreecommitdiff
path: root/arch/arm64/kvm/hyp/nvhe/tlb.c
AgeCommit message (Collapse)Author
2024-08-15KVM: arm64: Ensure TLBI uses correct VMID after changing contextWill Deacon
When the target context passed to enter_vmid_context() matches the current running context, the function returns early without manipulating the registers of the stage-2 MMU. This can result in a stale VMID due to the lack of an ISB instruction in exit_vmid_context() after writing the VTTBR when ARM64_WORKAROUND_SPECULATIVE_AT is not enabled. For example, with pKVM enabled: // Initially running in host context enter_vmid_context(guest); -> __load_stage2(guest); isb // Writes VTCR & VTTBR exit_vmid_context(guest); -> __load_stage2(host); // Restores VTCR & VTTBR enter_vmid_context(host); -> Returns early as we're already in host context tlbi vmalls12e1is // !!! Can use the stale VMID as we // haven't performed context // synchronisation since restoring // VTTBR.VMID Add an unconditional ISB instruction to exit_vmid_context() after restoring the VTTBR. This already existed for the ARM64_WORKAROUND_SPECULATIVE_AT path, so we can simply hoist that onto the common path. Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Fuad Tabba <tabba@google.com> Fixes: 58f3b0fc3b87 ("KVM: arm64: Support TLB invalidation in guest context") Signed-off-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20240814123429.20457-3-will@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-03Merge branch kvm-arm64/pkvm-6.10 into kvmarm-master/nextMarc Zyngier
* kvm-arm64/pkvm-6.10: (25 commits) : . : At last, a bunch of pKVM patches, courtesy of Fuad Tabba. : From the cover letter: : : "This series is a bit of a bombay-mix of patches we've been : carrying. There's no one overarching theme, but they do improve : the code by fixing existing bugs in pKVM, refactoring code to : make it more readable and easier to re-use for pKVM, or adding : functionality to the existing pKVM code upstream." : . KVM: arm64: Force injection of a data abort on NISV MMIO exit KVM: arm64: Restrict supported capabilities for protected VMs KVM: arm64: Refactor setting the return value in kvm_vm_ioctl_enable_cap() KVM: arm64: Document the KVM/arm64-specific calls in hypercalls.rst KVM: arm64: Rename firmware pseudo-register documentation file KVM: arm64: Reformat/beautify PTP hypercall documentation KVM: arm64: Clarify rationale for ZCR_EL1 value restored on guest exit KVM: arm64: Introduce and use predicates that check for protected VMs KVM: arm64: Add is_pkvm_initialized() helper KVM: arm64: Simplify vgic-v3 hypercalls KVM: arm64: Move setting the page as dirty out of the critical section KVM: arm64: Change kvm_handle_mmio_return() return polarity KVM: arm64: Fix comment for __pkvm_vcpu_init_traps() KVM: arm64: Prevent kmemleak from accessing .hyp.data KVM: arm64: Do not map the host fpsimd state to hyp in pKVM KVM: arm64: Rename __tlb_switch_to_{guest,host}() in VHE KVM: arm64: Support TLB invalidation in guest context KVM: arm64: Avoid BBM when changing only s/w bits in Stage-2 PTE KVM: arm64: Check for PTE validity when checking for executable/cacheable KVM: arm64: Avoid BUG-ing from the host abort path ... Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01KVM: arm64: Support TLB invalidation in guest contextWill Deacon
Typically, TLB invalidation of guest stage-2 mappings using nVHE is performed by a hypercall originating from the host. For the invalidation instruction to be effective, therefore, __tlb_switch_to_{guest,host}() swizzle the active stage-2 context around the TLBI instruction. With guest-to-host memory sharing and unsharing hypercalls originating from the guest under pKVM, there is need to support both guest and host VMID invalidations issued from guest context. Replace the __tlb_switch_to_{guest,host}() functions with a more general {enter,exit}_vmid_context() implementation which supports being invoked from guest context and acts as a no-op if the target context matches the running context. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Fuad Tabba <tabba@google.com> Acked-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240423150538.2103045-10-tabba@google.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-04-01KVM: arm64: Use TLBI_TTL_UNKNOWN in __kvm_tlb_flush_vmid_range()Will Deacon
Commit c910f2b65518 ("arm64/mm: Update tlb invalidation routines for FEAT_LPA2") updated the __tlbi_level() macro to take the target level as an argument, with TLBI_TTL_UNKNOWN (rather than 0) indicating that the caller cannot provide level information. Unfortunately, the two implementations of __kvm_tlb_flush_vmid_range() were not updated and so now ask for an level 0 invalidation if FEAT_LPA2 is implemented. Fix the problem by passing TLBI_TTL_UNKNOWN instead of 0 as the level argument to __flush_s2_tlb_range_op() in __kvm_tlb_flush_vmid_range(). Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Marc Zyngier <maz@kernel.org> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Fixes: c910f2b65518 ("arm64/mm: Update tlb invalidation routines for FEAT_LPA2") Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Shaoqin Huang <shahuang@redhat.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240327124853.11206-4-will@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-12-05KVM: arm64: Remove VPIPT I-cache handlingMarc Zyngier
We have some special handling for VPIPT I-cache in critical parts of the cache and TLB maintenance. Remove it. Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20231204143606.1806432-2-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2023-08-17KVM: arm64: Implement __kvm_tlb_flush_vmid_range()Raghavendra Rao Ananta
Define __kvm_tlb_flush_vmid_range() (for VHE and nVHE) to flush a range of stage-2 page-tables using IPA in one go. If the system supports FEAT_TLBIRANGE, the following patches would conveniently replace global TLBI such as vmalls12e1is in the map, unmap, and dirty-logging paths with ripas2e1is instead. Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shaoqin Huang <shahuang@redhat.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230811045127.3308641-10-rananta@google.com
2023-05-16KVM: arm64: Use local TLBI on permission relaxationMarc Zyngier
Broadcast TLB invalidations (TLBIs) targeting the Inner Shareable Domain are usually less performant than their non-shareable variant. In particular, we observed some implementations that take millliseconds to complete parallel broadcasted TLBIs. It's safe to use non-shareable TLBIs when relaxing permissions on a PTE in the KVM case. According to the ARM ARM (0487I.a) section D8.13.1 "Using break-before-make when updating translation table entries", permission relaxation does not need break-before-make. Specifically, R_WHZWS states that these are the only changes that require a break-before-make sequence: changes of memory type (Shareability or Cacheability), address changes, or changing the block size. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Ricardo Koller <ricarkol@google.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Link: https://lore.kernel.org/r/20230426172330.1439644-13-ricarkol@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-04-14KVM: arm64: nvhe: Synchronise with page table walker on TLBIMarc Zyngier
A TLBI from EL2 impacting EL1 involves messing with the EL1&0 translation regime, and the page table walker may still be performing speculative walks. Piggyback on the existing DSBs to always have a DSB ISH that will synchronise all load/store operations that the PTW may still have. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-08-20KVM: arm64: Unify stage-2 programming behind __load_stage2()Marc Zyngier
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 Zyngier
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
2021-05-25arm64: Rename arm64-internal cache maintenance functionsFuad Tabba
Although naming across the codebase isn't that consistent, it tends to follow certain patterns. Moreover, the term "flush" isn't defined in the Arm Architecture reference manual, and might be interpreted to mean clean, invalidate, or both for a cache. Rename arm64-internal functions to make the naming internally consistent, as well as making it consistent with the Arm ARM, by specifying whether it applies to the instruction, data, or both caches, whether the operation is a clean, invalidate, or both. Also specify which point the operation applies to, i.e., to the point of unification (PoU), coherency (PoC), or persistence (PoP). This commit applies the following sed transformation to all files under arch/arm64: "s/\b__flush_cache_range\b/caches_clean_inval_pou_macro/g;"\ "s/\b__flush_icache_range\b/caches_clean_inval_pou/g;"\ "s/\binvalidate_icache_range\b/icache_inval_pou/g;"\ "s/\b__flush_dcache_area\b/dcache_clean_inval_poc/g;"\ "s/\b__inval_dcache_area\b/dcache_inval_poc/g;"\ "s/__clean_dcache_area_poc\b/dcache_clean_poc/g;"\ "s/\b__clean_dcache_area_pop\b/dcache_clean_pop/g;"\ "s/\b__clean_dcache_area_pou\b/dcache_clean_pou/g;"\ "s/\b__flush_cache_user_range\b/caches_clean_inval_user_pou/g;"\ "s/\b__flush_icache_all\b/icache_inval_all_pou/g;" Note that __clean_dcache_area_poc is deliberately missing a word boundary check at the beginning in order to match the efistub symbols in image-vars.h. Also note that, despite its name, __flush_icache_range operates on both instruction and data caches. The name change here reflects that. No functional change intended. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Fuad Tabba <tabba@google.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20210524083001.2586635-19-tabba@google.com Signed-off-by: Will Deacon <will@kernel.org>
2021-03-19KVM: arm64: Wrap the host with a stage 2Quentin Perret
When KVM runs in protected nVHE mode, make use of a stage 2 page-table to give the hypervisor some control over the host memory accesses. The host stage 2 is created lazily using large block mappings if possible, and will default to page mappings in absence of a better solution. >From this point on, memory accesses from the host to protected memory regions (e.g. not 'owned' by the host) are fatal and lead to hyp_panic(). Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210319100146.1149909-36-qperret@google.com
2021-03-09KVM: arm64: Ensure I-cache isolation between vcpus of a same VMMarc Zyngier
It recently became apparent that the ARMv8 architecture has interesting rules regarding attributes being used when fetching instructions if the MMU is off at Stage-1. In this situation, the CPU is allowed to fetch from the PoC and allocate into the I-cache (unless the memory is mapped with the XN attribute at Stage-2). If we transpose this to vcpus sharing a single physical CPU, it is possible for a vcpu running with its MMU off to influence another vcpu running with its MMU on, as the latter is expected to fetch from the PoU (and self-patching code doesn't flush below that level). In order to solve this, reuse the vcpu-private TLB invalidation code to apply the same policy to the I-cache, nuking it every time the vcpu runs on a physical CPU that ran another vcpu of the same VM in the past. This involve renaming __kvm_tlb_flush_local_vmid() to __kvm_flush_cpu_context(), and inserting a local i-cache invalidation there. Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20210303164505.68492-1-maz@kernel.org
2020-10-30Merge tag 'kvmarm-fixes-5.10-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.10, take #1 - Force PTE mapping on device pages provided via VFIO - Fix detection of cacheable mapping at S2 - Fallback to PMD/PTE mappings for composite huge pages - Fix accounting of Stage-2 PGD allocation - Fix AArch32 handling of some of the debug registers - Simplify host HYP entry - Fix stray pointer conversion on nVHE TLB invalidation - Fix initialization of the nVHE code - Simplify handling of capabilities exposed to HYP - Nuke VCPUs caught using a forbidden AArch32 EL0
2020-10-29KVM: arm64: Remove leftover kern_hyp_va() in nVHE TLB invalidationMarc Zyngier
The new calling convention says that pointers coming from the SMCCC interface are turned into their HYP version in the host HVC handler. However, there is still a stray kern_hyp_va() in the TLB invalidation code, which could result in a corrupted pointer. Drop the spurious conversion. Fixes: a071261d9318 ("KVM: arm64: nVHE: Fix pointers during SMCCC convertion") Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20201026095116.72051-3-maz@kernel.org
2020-10-21Merge branch 'kvm-fixes' into 'next'Paolo Bonzini
Pick up bugfixes from 5.9, otherwise various tests fail.
2020-10-01KVM: arm64: Restore missing ISB on nVHE __tlb_switch_to_guestMarc Zyngier
Commit a0e50aa3f4a8 ("KVM: arm64: Factor out stage 2 page table data from struct kvm") dropped the ISB after __load_guest_stage2(), only leaving the one that is required when the speculative AT workaround is in effect. As Andrew points it: "This alternative is 'backwards' to avoid a double ISB as there is one in __load_guest_stage2 when the workaround is active." Restore the missing ISB, conditionned on the AT workaround not being active. Fixes: a0e50aa3f4a8 ("KVM: arm64: Factor out stage 2 page table data from struct kvm") Reported-by: Andrew Scull <ascull@google.com> Reported-by: Thomas Tai <thomas.tai@oracle.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-09-15KVM: arm64: nVHE: Fix pointers during SMCCC convertionAndrew Scull
The host need not concern itself with the pointer differences for the hyp interfaces that are shared between VHE and nVHE so leave it to the hyp to handle. As the SMCCC function IDs are converted into function calls, it is a suitable place to also convert any pointer arguments into hyp pointers. This, additionally, eases the reuse of the handlers in different contexts. Signed-off-by: Andrew Scull <ascull@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200915104643.2543892-20-ascull@google.com
2020-07-07KVM: arm64: Use TTL hint in when invalidating stage-2 translationsMarc Zyngier
Since we often have a precise idea of the level we're dealing with when invalidating TLBs, we can provide it to as a hint to our invalidation helper. Reviewed-by: James Morse <james.morse@arm.com> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-07KVM: arm64: Factor out stage 2 page table data from struct kvmChristoffer Dall
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: Remove __hyp_text macro, use build rules insteadDavid Brazdil
With nVHE code now fully separated from the rest of the kernel, the effects of the __hyp_text macro (which had to be applied on all nVHE code) can be achieved with build rules instead. The macro used to: (a) move code to .hyp.text ELF section, now done by renaming .text using `objcopy`, and (b) `notrace` and `__noscs` would negate effects of CC_FLAGS_FTRACE and CC_FLAGS_SCS, respectivelly, now those flags are erased from KBUILD_CFLAGS (same way as in EFI stub). Note that by removing __hyp_text from code shared with VHE, all VHE code is now compiled into .text and without `notrace` and `__noscs`. Use of '.pushsection .hyp.text' removed from assembly files as this is now also covered by the build rules. For MAINTAINERS: if needed to re-run, uses of macro were removed with the following command. Formatting was fixed up manually. find arch/arm64/kvm/hyp -type f -name '*.c' -o -name '*.h' \ -exec sed -i 's/ __hyp_text//g' {} + Signed-off-by: David Brazdil <dbrazdil@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200625131420.71444-15-dbrazdil@google.com
2020-07-05KVM: arm64: Duplicate hyp/tlb.c for VHE/nVHEDavid Brazdil
tlb.c contains code for flushing the TLB, with code shared between VHE/nVHE. Because common code is small, duplicate tlb.c and specialize each copy for VHE/nVHE. Signed-off-by: David Brazdil <dbrazdil@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200625131420.71444-9-dbrazdil@google.com