linux_dsm_epyc7002/arch/arm64/include/asm/virt.h
Jintack Lim 488f94d721 KVM: arm64: Access CNTHCTL_EL2 bit fields correctly on VHE systems
Current KVM world switch code is unintentionally setting wrong bits to
CNTHCTL_EL2 when E2H == 1, which may allow guest OS to access physical
timer.  Bit positions of CNTHCTL_EL2 are changing depending on
HCR_EL2.E2H bit.  EL1PCEN and EL1PCTEN are 1st and 0th bits when E2H is
not set, but they are 11th and 10th bits respectively when E2H is set.

In fact, on VHE we only need to set those bits once, not for every world
switch. This is because the host kernel runs in EL2 with HCR_EL2.TGE ==
1, which makes those bits have no effect for the host kernel execution.
So we just set those bits once for guests, and that's it.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-13 11:19:25 +00:00

101 lines
2.7 KiB
C

/*
* Copyright (C) 2012 ARM Ltd.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM__VIRT_H
#define __ASM__VIRT_H
/*
* The arm64 hcall implementation uses x0 to specify the hcall type. A value
* less than 0xfff indicates a special hcall, such as get/set vector.
* Any other value is used as a pointer to the function to call.
*/
/* HVC_GET_VECTORS - Return the value of the vbar_el2 register. */
#define HVC_GET_VECTORS 0
/*
* HVC_SET_VECTORS - Set the value of the vbar_el2 register.
*
* @x1: Physical address of the new vector table.
*/
#define HVC_SET_VECTORS 1
/*
* HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine.
*/
#define HVC_SOFT_RESTART 2
#define BOOT_CPU_MODE_EL1 (0xe11)
#define BOOT_CPU_MODE_EL2 (0xe12)
#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 0 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];
void __hyp_set_vectors(phys_addr_t phys_vector_base);
phys_addr_t __hyp_get_vectors(void);
/* Reports the availability of HYP mode */
static inline bool is_hyp_mode_available(void)
{
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)
{
return __boot_cpu_mode[0] != __boot_cpu_mode[1];
}
static inline bool is_kernel_in_hyp_mode(void)
{
return read_sysreg(CurrentEL) == CurrentEL_EL2;
}
static inline bool has_vhe(void)
{
if (cpus_have_const_cap(ARM64_HAS_VIRT_HOST_EXTN))
return true;
return false;
}
#ifdef CONFIG_ARM64_VHE
extern void verify_cpu_run_el(void);
#else
static inline void verify_cpu_run_el(void) {}
#endif
#endif /* __ASSEMBLY__ */
#endif /* ! __ASM__VIRT_H */