linux/arch/arm64/include/asm/virt.h

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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#ifndef __ASM__VIRT_H
#define __ASM__VIRT_H
/*
* The arm64 hcall implementation uses x0 to specify the hcall
* number. A value less than HVC_STUB_HCALL_NR indicates a special
* hcall, such as set vector. Any other value is handled in a
* hypervisor specific way.
*
* The hypercall is allowed to clobber any of the caller-saved
* registers (x0-x18), so it is advisable to use it through the
* indirection of a function call (as implemented in hyp-stub.S).
*/
/*
* HVC_SET_VECTORS - Set the value of the vbar_el2 register.
*
* @x1: Physical address of the new vector table.
*/
#define HVC_SET_VECTORS 0
/*
* HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine.
*/
#define HVC_SOFT_RESTART 1
/*
* HVC_RESET_VECTORS - Restore the vectors to the original HYP stubs
*/
#define HVC_RESET_VECTORS 2
/*
* HVC_FINALISE_EL2 - Upgrade the CPU from EL1 to EL2, if possible
*/
#define HVC_FINALISE_EL2 3
/* Max number of HYP stub hypercalls */
#define HVC_STUB_HCALL_NR 4
/* Error returned when an invalid stub number is passed into x0 */
#define HVC_STUB_ERR 0xbadca11
#define BOOT_CPU_MODE_EL1 (0xe11)
#define BOOT_CPU_MODE_EL2 (0xe12)
/*
* Flags returned together with the boot mode, but not preserved in
* __boot_cpu_mode. Used by the idreg override code to work out the
* boot state.
*/
#define BOOT_CPU_FLAG_E2H BIT_ULL(32)
#ifndef __ASSEMBLY__
#include <asm/ptrace.h>
#include <asm/sections.h>
#include <asm/sysreg.h>
#include <asm/cpufeature.h>
/*
* __boot_cpu_mode records what mode CPUs were booted in.
* A correctly-implemented bootloader must start all CPUs in the same mode:
* In this case, both 32bit halves of __boot_cpu_mode will contain the
* same value (either BOOT_CPU_MODE_EL1 if booted in EL1, BOOT_CPU_MODE_EL2 if
* booted in EL2).
*
* Should the bootloader fail to do this, the two values will be different.
* This allows the kernel to flag an error when the secondaries have come up.
*/
extern u32 __boot_cpu_mode[2];
#define ARM64_VECTOR_TABLE_LEN SZ_2K
void __hyp_set_vectors(phys_addr_t phys_vector_base);
void __hyp_reset_vectors(void);
KVM: arm64: Handle kvm_arm_init failure correctly in finalize_pkvm Currently there is no synchronisation between finalize_pkvm() and kvm_arm_init() initcalls. The finalize_pkvm() proceeds happily even if kvm_arm_init() fails resulting in the following warning on all the CPUs and eventually a HYP panic: | kvm [1]: IPA Size Limit: 48 bits | kvm [1]: Failed to init hyp memory protection | kvm [1]: error initializing Hyp mode: -22 | | <snip> | | WARNING: CPU: 0 PID: 0 at arch/arm64/kvm/pkvm.c:226 _kvm_host_prot_finalize+0x30/0x50 | Modules linked in: | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0 #237 | Hardware name: FVP Base RevC (DT) | pstate: 634020c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--) | pc : _kvm_host_prot_finalize+0x30/0x50 | lr : __flush_smp_call_function_queue+0xd8/0x230 | | Call trace: | _kvm_host_prot_finalize+0x3c/0x50 | on_each_cpu_cond_mask+0x3c/0x6c | pkvm_drop_host_privileges+0x4c/0x78 | finalize_pkvm+0x3c/0x5c | do_one_initcall+0xcc/0x240 | do_initcall_level+0x8c/0xac | do_initcalls+0x54/0x94 | do_basic_setup+0x1c/0x28 | kernel_init_freeable+0x100/0x16c | kernel_init+0x20/0x1a0 | ret_from_fork+0x10/0x20 | Failed to finalize Hyp protection: -22 | dtb=fvp-base-revc.dtb | kvm [95]: nVHE hyp BUG at: arch/arm64/kvm/hyp/nvhe/mem_protect.c:540! | kvm [95]: nVHE call trace: | kvm [95]: [<ffff800081052984>] __kvm_nvhe_hyp_panic+0xac/0xf8 | kvm [95]: [<ffff800081059644>] __kvm_nvhe_handle_host_mem_abort+0x1a0/0x2ac | kvm [95]: [<ffff80008105511c>] __kvm_nvhe_handle_trap+0x4c/0x160 | kvm [95]: [<ffff8000810540fc>] __kvm_nvhe___skip_pauth_save+0x4/0x4 | kvm [95]: ---[ end nVHE call trace ]--- | kvm [95]: Hyp Offset: 0xfffe8db00ffa0000 | Kernel panic - not syncing: HYP panic: | PS:a34023c9 PC:0000f250710b973c ESR:00000000f2000800 | FAR:ffff000800cb00d0 HPFAR:000000000880cb00 PAR:0000000000000000 | VCPU:0000000000000000 | CPU: 3 PID: 95 Comm: kworker/u16:2 Tainted: G W 6.4.0 #237 | Hardware name: FVP Base RevC (DT) | Workqueue: rpciod rpc_async_schedule | Call trace: | dump_backtrace+0xec/0x108 | show_stack+0x18/0x2c | dump_stack_lvl+0x50/0x68 | dump_stack+0x18/0x24 | panic+0x138/0x33c | nvhe_hyp_panic_handler+0x100/0x184 | new_slab+0x23c/0x54c | ___slab_alloc+0x3e4/0x770 | kmem_cache_alloc_node+0x1f0/0x278 | __alloc_skb+0xdc/0x294 | tcp_stream_alloc_skb+0x2c/0xf0 | tcp_sendmsg_locked+0x3d0/0xda4 | tcp_sendmsg+0x38/0x5c | inet_sendmsg+0x44/0x60 | sock_sendmsg+0x1c/0x34 | xprt_sock_sendmsg+0xdc/0x274 | xs_tcp_send_request+0x1ac/0x28c | xprt_transmit+0xcc/0x300 | call_transmit+0x78/0x90 | __rpc_execute+0x114/0x3d8 | rpc_async_schedule+0x28/0x48 | process_one_work+0x1d8/0x314 | worker_thread+0x248/0x474 | kthread+0xfc/0x184 | ret_from_fork+0x10/0x20 | SMP: stopping secondary CPUs | Kernel Offset: 0x57c5cb460000 from 0xffff800080000000 | PHYS_OFFSET: 0x80000000 | CPU features: 0x00000000,1035b7a3,ccfe773f | Memory Limit: none | ---[ end Kernel panic - not syncing: HYP panic: | PS:a34023c9 PC:0000f250710b973c ESR:00000000f2000800 | FAR:ffff000800cb00d0 HPFAR:000000000880cb00 PAR:0000000000000000 | VCPU:0000000000000000 ]--- Fix it by checking for the successfull initialisation of kvm_arm_init() in finalize_pkvm() before proceeding any futher. Fixes: 87727ba2bb05 ("KVM: arm64: Ensure CPU PMU probes before pKVM host de-privilege") Cc: Will Deacon <will@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: James Morse <james.morse@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230704193243.3300506-1-sudeep.holla@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-07-04 20:32:43 +01:00
bool is_kvm_arm_initialised(void);
DECLARE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
static inline bool is_pkvm_initialized(void)
{
return IS_ENABLED(CONFIG_KVM) &&
static_branch_likely(&kvm_protected_mode_initialized);
}
/* Reports the availability of HYP mode */
static inline bool is_hyp_mode_available(void)
{
/*
* If KVM protected mode is initialized, all CPUs must have been booted
* in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1.
*/
if (is_pkvm_initialized())
return true;
return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 &&
__boot_cpu_mode[1] == BOOT_CPU_MODE_EL2);
}
/* Check if the bootloader has booted CPUs in different modes */
static inline bool is_hyp_mode_mismatched(void)
{
/*
* If KVM protected mode is initialized, all CPUs must have been booted
* in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1.
*/
if (is_pkvm_initialized())
return false;
return __boot_cpu_mode[0] != __boot_cpu_mode[1];
}
static __always_inline bool is_kernel_in_hyp_mode(void)
{
BUILD_BUG_ON(__is_defined(__KVM_NVHE_HYPERVISOR__) ||
__is_defined(__KVM_VHE_HYPERVISOR__));
return read_sysreg(CurrentEL) == CurrentEL_EL2;
}
static __always_inline bool has_vhe(void)
{
/*
* Code only run in VHE/NVHE hyp context can assume VHE is present or
* absent. Otherwise fall back to caps.
* This allows the compiler to discard VHE-specific code from the
* nVHE object, reducing the number of external symbol references
* needed to link.
*/
if (is_vhe_hyp_code())
return true;
else if (is_nvhe_hyp_code())
return false;
else
return cpus_have_final_cap(ARM64_HAS_VIRT_HOST_EXTN);
}
static __always_inline bool is_protected_kvm_enabled(void)
{
if (is_vhe_hyp_code())
return false;
else
return cpus_have_final_cap(ARM64_KVM_PROTECTED_MODE);
}
static __always_inline bool has_hvhe(void)
{
if (is_vhe_hyp_code())
return false;
return cpus_have_final_cap(ARM64_KVM_HVHE);
}
static inline bool is_hyp_nvhe(void)
{
return is_hyp_mode_available() && !is_kernel_in_hyp_mode();
}
#endif /* __ASSEMBLY__ */
#endif /* ! __ASM__VIRT_H */