Quentin Perret 2e40316753 KVM: arm64: Don't hypercall before EL2 init ... Will reported the following splat when running with Protected KVM enabled: [ 2.427181] ------------[ cut here ]------------ [ 2.427668] WARNING: CPU: 3 PID: 1 at arch/arm64/kvm/mmu.c:489 __create_hyp_private_mapping+0x118/0x1ac [ 2.428424] Modules linked in: [ 2.429040] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.18.0-rc2-00084-g8635adc4efc7 #1 [ 2.429589] Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 [ 2.430286] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.430734] pc : __create_hyp_private_mapping+0x118/0x1ac [ 2.431091] lr : create_hyp_exec_mappings+0x40/0x80 [ 2.431377] sp : ffff80000803baf0 [ 2.431597] x29: ffff80000803bb00 x28: 0000000000000000 x27: 0000000000000000 [ 2.432156] x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 [ 2.432561] x23: ffffcd96c343b000 x22: 0000000000000000 x21: ffff80000803bb40 [ 2.433004] x20: 0000000000000004 x19: 0000000000001800 x18: 0000000000000000 [ 2.433343] x17: 0003e68cf7efdd70 x16: 0000000000000004 x15: fffffc81f602a2c8 [ 2.434053] x14: ffffdf8380000000 x13: ffffcd9573200000 x12: ffffcd96c343b000 [ 2.434401] x11: 0000000000000004 x10: ffffcd96c1738000 x9 : 0000000000000004 [ 2.434812] x8 : ffff80000803bb40 x7 : 7f7f7f7f7f7f7f7f x6 : 544f422effff306b [ 2.435136] x5 : 000000008020001e x4 : ffff207d80a88c00 x3 : 0000000000000005 [ 2.435480] x2 : 0000000000001800 x1 : 000000014f4ab800 x0 : 000000000badca11 [ 2.436149] Call trace: [ 2.436600] __create_hyp_private_mapping+0x118/0x1ac [ 2.437576] create_hyp_exec_mappings+0x40/0x80 [ 2.438180] kvm_init_vector_slots+0x180/0x194 [ 2.458941] kvm_arch_init+0x80/0x274 [ 2.459220] kvm_init+0x48/0x354 [ 2.459416] arm_init+0x20/0x2c [ 2.459601] do_one_initcall+0xbc/0x238 [ 2.459809] do_initcall_level+0x94/0xb4 [ 2.460043] do_initcalls+0x54/0x94 [ 2.460228] do_basic_setup+0x1c/0x28 [ 2.460407] kernel_init_freeable+0x110/0x178 [ 2.460610] kernel_init+0x20/0x1a0 [ 2.460817] ret_from_fork+0x10/0x20 [ 2.461274] ---[ end trace 0000000000000000 ]--- Indeed, the Protected KVM mode promotes __create_hyp_private_mapping() to a hypercall as EL1 no longer has access to the hypervisor's stage-1 page-table. However, the call from kvm_init_vector_slots() happens after pKVM has been initialized on the primary CPU, but before it has been initialized on secondaries. As such, if the KVM initcall procedure is migrated from one CPU to another in this window, the hypercall may end up running on a CPU for which EL2 has not been initialized. Fortunately, the pKVM hypervisor doesn't rely on the host to re-map the vectors in the private range, so the hypercall in question is in fact superfluous. Skip it when pKVM is enabled. Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> [maz: simplified the checks slightly] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220513092607.35233-1-qperret@google.com		2022-05-15 12:14:14 +01:00
..
hyp	KVM: arm64: Handle host stage-2 faults from 32-bit EL0	2022-04-27 21:54:30 +01:00
vgic	KVM: arm64: vgic: Remove unnecessary type castings	2022-04-06 10:42:55 +01:00
.gitignore	KVM: arm64: Generate hyp_constants.h for the host	2021-12-06 08:37:03 +00:00
arch_timer.c	KVM: Add helpers to wake/query blocking vCPU	2021-12-08 04:24:54 -05:00
arm.c	KVM: arm64: Don't hypercall before EL2 init	2022-05-15 12:14:14 +01:00
debug.c	KVM: arm64: Emulate the OS Lock	2022-02-08 14:23:41 +00:00
fpsimd.c	KVM: arm64: Add comments for context flush and sync callbacks	2022-02-08 14:42:59 +00:00
guest.c	KVM: arm64: fix typos in comments	2022-03-18 14:04:15 +00:00
handle_exit.c	KVM: arm64: fix typos in comments	2022-03-18 14:04:15 +00:00
hypercalls.c	KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated	2022-02-24 13:58:52 +00:00
inject_fault.c	KVM: arm64: Inject exception on out-of-IPA-range translation fault	2022-04-27 23:02:23 +01:00
irq.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 422	2019-06-05 17:37:15 +02:00
Kconfig	RISCV:	2022-01-16 16:15:14 +02:00
Makefile	KVM: arm64: Align the VMID allocation with the arm64 ASID	2022-02-08 14:57:03 +00:00
mmio.c	KVM: arm64: Generalise VM features into a set of flags	2022-03-18 14:02:33 +00:00
mmu.c	KVM: arm64: Inject exception on out-of-IPA-range translation fault	2022-04-27 23:02:23 +01:00
pkvm.c	KVM: arm64: Move host EL1 code out of hyp/ directory	2021-12-06 08:37:03 +00:00
pmu-emul.c	KVM/arm64: Don't emulate a PMU for 32-bit guests if feature not set	2022-04-27 22:10:29 +01:00
pmu.c	KVM: arm64: Disable PMU support in protected mode	2021-03-19 12:02:19 +00:00
psci.c	KVM: arm64: Drop unneeded minor version check from PSCI v1.x handler	2022-04-06 10:39:39 +01:00
pvtime.c	KVM: arm64: Use kvm_write_guest_lock when init stolen time	2020-12-03 19:02:18 +00:00
reset.c	KVM: arm64: mixed-width check should be skipped for uninitialized vCPUs	2022-04-06 12:29:45 +01:00
sys_regs.c	KVM: arm64: vgic-v3: Consistently populate ID_AA64PFR0_EL1.GIC	2022-05-15 12:12:14 +01:00
sys_regs.h	KVM: arm64: Refactor sys_regs.h,c for nVHE reuse	2021-08-20 11:12:17 +01:00
trace_arm.h	KVM: Move arm64's MMU notifier trace events to generic code	2021-04-17 08:30:56 -04:00
trace_handle_exit.h	KVM: arm64: Upgrade trace_kvm_arm_set_dreg32() to 64bit	2021-08-20 11:12:18 +01:00
trace.h	KVM: arm64: Move virt/kvm/arm to arch/arm64	2020-05-16 15:03:59 +01:00
trng.c	KVM: arm64: Implement the TRNG hypervisor call	2021-01-25 22:19:31 +00:00
va_layout.c	KVM: arm64: Generate final CTR_EL0 value when running in Protected mode	2021-03-25 11:00:33 +00:00
vgic-sys-reg-v3.c	KVM: arm64: Drop is_aarch32 trap attribute	2020-11-10 11:22:52 +00:00
vmid.c	KVM: arm64: Make active_vmids invalid on vCPU schedule out	2022-02-08 14:57:04 +00:00