pm24.git/arch/arm64, branch cpufreq-rust

Merge tag 'kvmarm-fixes-6.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2025-02-04T16:14:53Z

KVM/arm64 fixes for 6.14, take #1 - Correctly clean the BSS to the PoC before allowing EL2 to access it on nVHE/hVHE/protected configurations - Propagate ownership of debug registers in protected mode after the rework that landed in 6.14-rc1 - Stop pretending that we can run the protected mode without a GICv3 being present on the host - Fix a use-after-free situation that can occur if a vcpu fails to initialise the NV shadow S2 MMU contexts - Always evaluate the need to arm a background timer for fully emulated guest timers - Fix the emulation of EL1 timers in the absence of FEAT_ECV - Correctly handle the EL2 virtual timer, specially when HCR_EL2.E2H==0

KVM: arm64: timer: Don't adjust the EL2 virtual timer offset

2025-02-04T15:10:38Z

The way we deal with the EL2 virtual timer is a bit odd. We try to cope with E2H being flipped, and adjust which offset applies to that timer depending on the current E2H value. But that's a complexity we shouldn't have to worry about. What we have to deal with is either E2H being RES1, in which case there is no offset, or E2H being RES0, and the virtual timer simply does not exist. Drop the adjusting of the timer offset, which makes things a bit simpler. At the same time, make sure that accessing the HV timer when E2H is RES0 results in an UNDEF in the guest. Suggested-by: Oliver Upton Reviewed-by: Oliver Upton Link: https://lore.kernel.org/r/20250204110050.150560-4-maz@kernel.org Signed-off-by: Marc Zyngier

KVM: arm64: timer: Correctly handle EL1 timer emulation when !FEAT_ECV

2025-02-04T15:10:38Z

Both Wei-Lin Chang and Volodymyr Babchuk report that the way we handle the emulation of EL1 timers with NV is completely wrong, specially in the case of HCR_EL2.E2H==0. There are three problems in about as many lines of code: - With E2H==0, the EL1 timers are overwritten with the EL1 state, while they should actually contain the EL2 state (as per the timer map) - With E2H==1, we run the full EL1 timer emulation even when ECV is present, hiding a bug in timer_emulate() (see previous patch) - The comments are actively misleading, and say all the wrong things. This is only attributable to the code having been initially written for FEAT_NV, hacked up to handle FEAT_NV2 *in parallel*, and vaguely hacked again to be FEAT_NV2 only. Oh, and yours truly being a gold plated idiot. The fix is obvious: just delete most of the E2H==0 code, have a unified handling of the timers (because they really are E2H agnostic), and make sure we don't execute any of that when FEAT_ECV is present. Fixes: 4bad3068cfa9f ("KVM: arm64: nv: Sync nested timer state with FEAT_NV2") Reported-by: Wei-Lin Chang Reported-by: Volodymyr Babchuk Link: https://lore.kernel.org/r/fqiqfjzwpgbzdtouu2pwqlu7llhnf5lmy4hzv5vo6ph4v3vyls@jdcfy3fjjc5k Link: https://lore.kernel.org/r/87frl51tse.fsf@epam.com Tested-by: Dmytro Terletskyi Reviewed-by: Oliver Upton Link: https://lore.kernel.org/r/20250204110050.150560-3-maz@kernel.org Signed-off-by: Marc Zyngier

KVM: arm64: timer: Always evaluate the need for a soft timer

2025-02-04T15:10:38Z

When updating the interrupt state for an emulated timer, we return early and skip the setup of a soft timer that runs in parallel with the guest. While this is OK if we have set the interrupt pending, it is pretty wrong if the guest moved CVAL into the future. In that case, no timer is armed and the guest can wait for a very long time (it will take a full put/load cycle for the situation to resolve). This is specially visible with EDK2 running at EL2, but still using the EL1 virtual timer, which in that case is fully emulated. Any key-press takes ages to be captured, as there is no UART interrupt and EDK2 relies on polling from a timer... The fix is simply to drop the early return. If the timer interrupt is pending, we will still return early, and otherwise arm the soft timer. Fixes: 4d74ecfa6458b ("KVM: arm64: Don't arm a hrtimer for an already pending timer") Cc: stable@vger.kernel.org Tested-by: Dmytro Terletskyi Reviewed-by: Oliver Upton Link: https://lore.kernel.org/r/20250204110050.150560-2-maz@kernel.org Signed-off-by: Marc Zyngier

KVM: arm64: Fix nested S2 MMU structures reallocation

2025-02-04T15:02:16Z

For each vcpu that userspace creates, we allocate a number of s2_mmu structures that will eventually contain our shadow S2 page tables. Since this is a dynamically allocated array, we reallocate the array and initialise the newly allocated elements. Once everything is correctly initialised, we adjust pointer and size in the kvm structure, and move on. But should that initialisation fail *and* the reallocation triggered a copy to another location, we end-up returning early, with the kvm structure still containing the (now stale) old pointer. Weeee! Cure it by assigning the pointer early, and use this to perform the initialisation. If everything succeeds, we adjust the size. Otherwise, we just leave the size as it was, no harm done, and the new memory is as good as the ol' one (we hope...). Fixes: 4f128f8e1aaac ("KVM: arm64: nv: Support multiple nested Stage-2 mmu structures") Reported-by: Alexander Potapenko Tested-by: Alexander Potapenko Link: https://lore.kernel.org/r/20250204145554.774427-1-maz@kernel.org Signed-off-by: Marc Zyngier

KVM: arm64: Fail protected mode init if no vgic hardware is present

2025-02-04T10:49:23Z

Protected mode assumes that at minimum vgic-v3 is present, however KVM fails to actually enforce this at the time of initialization. As such, when running protected mode in a half-baked state on GICv2 hardware we see the hyp go belly up at vcpu_load() when it tries to restore the vgic-v3 cpuif: $ ./arch_timer_edge_cases [ 130.599140] kvm [4518]: nVHE hyp panic at: [] __kvm_nvhe___vgic_v3_restore_vmcr_aprs+0x8/0x84! [ 130.603685] kvm [4518]: Cannot dump pKVM nVHE stacktrace: !CONFIG_PROTECTED_NVHE_STACKTRACE [ 130.611962] kvm [4518]: Hyp Offset: 0xfffeca95ed000000 [ 130.617053] Kernel panic - not syncing: HYP panic: [ 130.617053] PS:800003c9 PC:0000b56a94102b58 ESR:0000000002000000 [ 130.617053] FAR:ffff00007b98d4d0 HPFAR:00000000007b98d0 PAR:0000000000000000 [ 130.617053] VCPU:0000000000000000 [ 130.638013] CPU: 0 UID: 0 PID: 4518 Comm: arch_timer_edge Tainted: G C 6.13.0-rc3-00009-gf7d03fcbf1f4 #1 [ 130.648790] Tainted: [C]=CRAP [ 130.651721] Hardware name: Libre Computer AML-S905X-CC (DT) [ 130.657242] Call trace: [ 130.659656] show_stack+0x18/0x24 (C) [ 130.663279] dump_stack_lvl+0x38/0x90 [ 130.666900] dump_stack+0x18/0x24 [ 130.670178] panic+0x388/0x3e8 [ 130.673196] nvhe_hyp_panic_handler+0x104/0x208 [ 130.677681] kvm_arch_vcpu_load+0x290/0x548 [ 130.681821] vcpu_load+0x50/0x80 [ 130.685013] kvm_arch_vcpu_ioctl_run+0x30/0x868 [ 130.689498] kvm_vcpu_ioctl+0x2e0/0x974 [ 130.693293] __arm64_sys_ioctl+0xb4/0xec [ 130.697174] invoke_syscall+0x48/0x110 [ 130.700883] el0_svc_common.constprop.0+0x40/0xe0 [ 130.705540] do_el0_svc+0x1c/0x28 [ 130.708818] el0_svc+0x30/0xd0 [ 130.711837] el0t_64_sync_handler+0x10c/0x138 [ 130.716149] el0t_64_sync+0x198/0x19c [ 130.719774] SMP: stopping secondary CPUs [ 130.723660] Kernel Offset: disabled [ 130.727103] CPU features: 0x000,00000800,02800000,0200421b [ 130.732537] Memory Limit: none [ 130.735561] ---[ end Kernel panic - not syncing: HYP panic: [ 130.735561] PS:800003c9 PC:0000b56a94102b58 ESR:0000000002000000 [ 130.735561] FAR:ffff00007b98d4d0 HPFAR:00000000007b98d0 PAR:0000000000000000 [ 130.735561] VCPU:0000000000000000 ]--- Fix it by failing KVM initialization if the system doesn't implement vgic-v3, as protected mode will never do anything useful on such hardware. Reported-by: Mark Brown Closes: https://lore.kernel.org/kvmarm/5ca7588c-7bf2-4352-8661-e4a56a9cd9aa@sirena.org.uk/ Signed-off-by: Oliver Upton Link: https://lore.kernel.org/r/20250203231543.233511-1-oliver.upton@linux.dev Signed-off-by: Marc Zyngier

KVM: arm64: Flush/sync debug state in protected mode

2025-02-01T09:31:11Z

The recent changes to debug state management broke self-hosted debug for guests when running in protected mode, since both the debug owner and the debug state itself aren't shared with the hyp's view of the vcpu. Fix it by flushing/syncing the relevant bits with the hyp vcpu. Fixes: beb470d96cec ("KVM: arm64: Use debug_owner to track if debug regs need save/restore") Reported-by: Mark Brown Closes: https://lore.kernel.org/kvmarm/5f62740f-a065-42d9-9f56-8fb648b9c63f@sirena.org.uk/ Signed-off-by: Oliver Upton Link: https://lore.kernel.org/r/20250131222922.1548780-3-oliver.upton@linux.dev Signed-off-by: Marc Zyngier

Merge tag 'constfy-sysctl-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl

2025-01-29T18:35:40Z

Pull sysctl table constification from Joel Granados: "All ctl_table declared outside of functions and that remain unmodified after initialization are const qualified. This prevents unintended modifications to proc_handler function pointers by placing them in the .rodata section. This is a continuation of the tree-wide effort started a few releases ago with the constification of the ctl_table struct arguments in the sysctl API done in 78eb4ea25cd5 ("sysctl: treewide: constify the ctl_table argument of proc_handlers")" * tag 'constfy-sysctl-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl: treewide: const qualify ctl_tables where applicable

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2025-01-28T17:01:36Z

Pull KVM/arm64 updates from Will Deacon: "New features: - Support for non-protected guest in protected mode, achieving near feature parity with the non-protected mode - Support for the EL2 timers as part of the ongoing NV support - Allow control of hardware tracing for nVHE/hVHE Improvements, fixes and cleanups: - Massive cleanup of the debug infrastructure, making it a bit less awkward and definitely easier to maintain. This should pave the way for further optimisations - Complete rewrite of pKVM's fixed-feature infrastructure, aligning it with the rest of KVM and making the code easier to follow - Large simplification of pKVM's memory protection infrastructure - Better handling of RES0/RES1 fields for memory-backed system registers - Add a workaround for Qualcomm's Snapdragon X CPUs, which suffer from a pretty nasty timer bug - Small collection of cleanups and low-impact fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (87 commits) arm64/sysreg: Get rid of TRFCR_ELx SysregFields KVM: arm64: nv: Fix doc header layout for timers KVM: arm64: nv: Apply RESx settings to sysreg reset values KVM: arm64: nv: Always evaluate HCR_EL2 using sanitising accessors KVM: arm64: Fix selftests after sysreg field name update coresight: Pass guest TRFCR value to KVM KVM: arm64: Support trace filtering for guests KVM: arm64: coresight: Give TRBE enabled state to KVM coresight: trbe: Remove redundant disable call arm64/sysreg/tools: Move TRFCR definitions to sysreg tools: arm64: Update sysreg.h header files KVM: arm64: Drop pkvm_mem_transition for host/hyp donations KVM: arm64: Drop pkvm_mem_transition for host/hyp sharing KVM: arm64: Drop pkvm_mem_transition for FF-A KVM: arm64: Explicitly handle BRBE traps as UNDEFINED KVM: arm64: vgic: Use str_enabled_disabled() in vgic_v3_probe() arm64: kvm: Introduce nvhe stack size constants KVM: arm64: Fix nVHE stacktrace VA bits mask KVM: arm64: Fix FEAT_MTE in pKVM Documentation: Update the behaviour of "kvm-arm.mode" ...

treewide: const qualify ctl_tables where applicable

2025-01-28T12:48:37Z

Add the const qualifier to all the ctl_tables in the tree except for watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls, loadpin_sysctl_table and the ones calling register_net_sysctl (./net, drivers/inifiniband dirs). These are special cases as they use a registration function with a non-const qualified ctl_table argument or modify the arrays before passing them on to the registration function. Constifying ctl_table structs will prevent the modification of proc_handler function pointers as the arrays would reside in .rodata. This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide: constify the ctl_table argument of proc_handlers") constified all the proc_handlers. Created this by running an spatch followed by a sed command: Spatch: virtual patch @ depends on !(file in "net") disable optional_qualifier @ identifier table_name != { watchdog_hardlockup_sysctl, iwcm_ctl_table, ucma_ctl_table, memory_allocation_profiling_sysctls, loadpin_sysctl_table }; @@ + const struct ctl_table table_name [] = { ... }; sed: sed --in-place \ -e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \ kernel/utsname_sysctl.c Reviewed-by: Song Liu Acked-by: Steven Rostedt (Google) # for kernel/trace/ Reviewed-by: Martin K. Petersen # SCSI Reviewed-by: Darrick J. Wong # xfs Acked-by: Jani Nikula Acked-by: Corey Minyard Acked-by: Wei Liu Acked-by: Thomas Gleixner Reviewed-by: Bill O'Donnell Acked-by: Baoquan He Acked-by: Ashutosh Dixit Acked-by: Anna Schumaker Signed-off-by: Joel Granados