![Suzuki K Poulose](/assets/img/avatar_default.png)
We expect all CPUs to be running at the same EL inside the kernel with or without VHE enabled and we have strict checks to ensure that any mismatch triggers a kernel panic. If VHE is enabled, we use the feature based on the boot CPU and all other CPUs should follow. This makes it a perfect candidate for a capability based on the boot CPU, which should be matched by all the CPUs (both when is ON and OFF). This saves us some not-so-pretty hooks and special code, just for verifying the conflict. The patch also makes the VHE capability entry depend on CONFIG_ARM64_VHE. Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
108 lines
3 KiB
C
108 lines
3 KiB
C
/*
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* Copyright (C) 2012 ARM Ltd.
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* Author: Marc Zyngier <marc.zyngier@arm.com>
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef __ASM__VIRT_H
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#define __ASM__VIRT_H
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/*
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* The arm64 hcall implementation uses x0 to specify the hcall
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* number. A value less than HVC_STUB_HCALL_NR indicates a special
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* hcall, such as set vector. Any other value is handled in a
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* hypervisor specific way.
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*
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* The hypercall is allowed to clobber any of the caller-saved
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* registers (x0-x18), so it is advisable to use it through the
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* indirection of a function call (as implemented in hyp-stub.S).
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*/
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/*
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* HVC_SET_VECTORS - Set the value of the vbar_el2 register.
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*
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* @x1: Physical address of the new vector table.
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*/
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#define HVC_SET_VECTORS 0
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/*
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* HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine.
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*/
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#define HVC_SOFT_RESTART 1
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/*
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* HVC_RESET_VECTORS - Restore the vectors to the original HYP stubs
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*/
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#define HVC_RESET_VECTORS 2
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/* Max number of HYP stub hypercalls */
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#define HVC_STUB_HCALL_NR 3
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/* Error returned when an invalid stub number is passed into x0 */
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#define HVC_STUB_ERR 0xbadca11
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#define BOOT_CPU_MODE_EL1 (0xe11)
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#define BOOT_CPU_MODE_EL2 (0xe12)
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#ifndef __ASSEMBLY__
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#include <asm/ptrace.h>
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#include <asm/sections.h>
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#include <asm/sysreg.h>
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#include <asm/cpufeature.h>
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/*
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* __boot_cpu_mode records what mode CPUs were booted in.
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* A correctly-implemented bootloader must start all CPUs in the same mode:
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* In this case, both 32bit halves of __boot_cpu_mode will contain the
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* same value (either 0 if booted in EL1, BOOT_CPU_MODE_EL2 if booted in EL2).
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*
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* Should the bootloader fail to do this, the two values will be different.
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* This allows the kernel to flag an error when the secondaries have come up.
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*/
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extern u32 __boot_cpu_mode[2];
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void __hyp_set_vectors(phys_addr_t phys_vector_base);
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void __hyp_reset_vectors(void);
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/* Reports the availability of HYP mode */
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static inline bool is_hyp_mode_available(void)
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{
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return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 &&
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__boot_cpu_mode[1] == BOOT_CPU_MODE_EL2);
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}
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/* Check if the bootloader has booted CPUs in different modes */
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static inline bool is_hyp_mode_mismatched(void)
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{
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return __boot_cpu_mode[0] != __boot_cpu_mode[1];
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}
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static inline bool is_kernel_in_hyp_mode(void)
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{
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return read_sysreg(CurrentEL) == CurrentEL_EL2;
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}
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static inline bool has_vhe(void)
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{
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if (cpus_have_const_cap(ARM64_HAS_VIRT_HOST_EXTN))
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return true;
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return false;
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}
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#endif /* __ASSEMBLY__ */
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#endif /* ! __ASM__VIRT_H */
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