linux-next/arch/arm/kernel/asm-offsets.c
Linus Walleij 7af5b901e8 ARM: 9358/2: Implement PAN for LPAE by TTBR0 page table walks disablement
With LPAE enabled, privileged no-access cannot be enforced using CPU
domains as such feature is not available. This patch implements PAN
by disabling TTBR0 page table walks while in kernel mode.

The ARM architecture allows page table walks to be split between TTBR0
and TTBR1. With LPAE enabled, the split is defined by a combination of
TTBCR T0SZ and T1SZ bits. Currently, an LPAE-enabled kernel uses TTBR0
for user addresses and TTBR1 for kernel addresses with the VMSPLIT_2G
and VMSPLIT_3G configurations. The main advantage for the 3:1 split is
that TTBR1 is reduced to 2 levels, so potentially faster TLB refill
(though usually the first level entries are already cached in the TLB).

The PAN support on LPAE-enabled kernels uses TTBR0 when running in user
space or in kernel space during user access routines (TTBCR T0SZ and
T1SZ are both 0). When running user accesses are disabled in kernel
mode, TTBR0 page table walks are disabled by setting TTBCR.EPD0. TTBR1
is used for kernel accesses (including loadable modules; anything
covered by swapper_pg_dir) by reducing the TTBCR.T0SZ to the minimum
(2^(32-7) = 32MB). To avoid user accesses potentially hitting stale TLB
entries, the ASID is switched to 0 (reserved) by setting TTBCR.A1 and
using the ASID value in TTBR1. The difference from a non-PAN kernel is
that with the 3:1 memory split, TTBR1 always uses 3 levels of page
tables.

As part of the change we are using preprocessor elif definied() clauses
so balance these clauses by converting relevant precedingt ifdef
clauses to if defined() clauses.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2024-04-18 12:10:46 +01:00

177 lines
7.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 1995-2003 Russell King
* 2001-2002 Keith Owens
*
* Generate definitions needed by assembly language modules.
* This code generates raw asm output which is post-processed to extract
* and format the required data.
*/
#include <linux/compiler.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <asm/cacheflush.h>
#include <asm/kexec-internal.h>
#include <asm/glue-df.h>
#include <asm/glue-pf.h>
#include <asm/mach/arch.h>
#include <asm/thread_info.h>
#include <asm/page.h>
#include <asm/mpu.h>
#include <asm/procinfo.h>
#include <asm/suspend.h>
#include <asm/hardware/cache-l2x0.h>
#include <linux/kbuild.h>
#include <linux/arm-smccc.h>
#include <vdso/datapage.h>
#include "signal.h"
/*
* Make sure that the compiler and target are compatible.
*/
#if defined(__APCS_26__)
#error Sorry, your compiler targets APCS-26 but this kernel requires APCS-32
#endif
int main(void)
{
DEFINE(TSK_ACTIVE_MM, offsetof(struct task_struct, active_mm));
#ifdef CONFIG_STACKPROTECTOR
DEFINE(TSK_STACK_CANARY, offsetof(struct task_struct, stack_canary));
#endif
BLANK();
DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
DEFINE(TI_CPU_DOMAIN, offsetof(struct thread_info, cpu_domain));
DEFINE(TI_CPU_SAVE, offsetof(struct thread_info, cpu_context));
DEFINE(TI_ABI_SYSCALL, offsetof(struct thread_info, abi_syscall));
DEFINE(TI_TP_VALUE, offsetof(struct thread_info, tp_value));
DEFINE(TI_FPSTATE, offsetof(struct thread_info, fpstate));
#ifdef CONFIG_VFP
DEFINE(TI_VFPSTATE, offsetof(struct thread_info, vfpstate));
#ifdef CONFIG_SMP
DEFINE(VFP_CPU, offsetof(union vfp_state, hard.cpu));
#endif
#endif
DEFINE(SOFTIRQ_DISABLE_OFFSET,SOFTIRQ_DISABLE_OFFSET);
#ifdef CONFIG_ARM_THUMBEE
DEFINE(TI_THUMBEE_STATE, offsetof(struct thread_info, thumbee_state));
#endif
#ifdef CONFIG_IWMMXT
DEFINE(TI_IWMMXT_STATE, offsetof(struct thread_info, fpstate.iwmmxt));
#endif
BLANK();
DEFINE(S_R0, offsetof(struct pt_regs, ARM_r0));
DEFINE(S_R1, offsetof(struct pt_regs, ARM_r1));
DEFINE(S_R2, offsetof(struct pt_regs, ARM_r2));
DEFINE(S_R3, offsetof(struct pt_regs, ARM_r3));
DEFINE(S_R4, offsetof(struct pt_regs, ARM_r4));
DEFINE(S_R5, offsetof(struct pt_regs, ARM_r5));
DEFINE(S_R6, offsetof(struct pt_regs, ARM_r6));
DEFINE(S_R7, offsetof(struct pt_regs, ARM_r7));
DEFINE(S_R8, offsetof(struct pt_regs, ARM_r8));
DEFINE(S_R9, offsetof(struct pt_regs, ARM_r9));
DEFINE(S_R10, offsetof(struct pt_regs, ARM_r10));
DEFINE(S_FP, offsetof(struct pt_regs, ARM_fp));
DEFINE(S_IP, offsetof(struct pt_regs, ARM_ip));
DEFINE(S_SP, offsetof(struct pt_regs, ARM_sp));
DEFINE(S_LR, offsetof(struct pt_regs, ARM_lr));
DEFINE(S_PC, offsetof(struct pt_regs, ARM_pc));
DEFINE(S_PSR, offsetof(struct pt_regs, ARM_cpsr));
DEFINE(S_OLD_R0, offsetof(struct pt_regs, ARM_ORIG_r0));
DEFINE(PT_REGS_SIZE, sizeof(struct pt_regs));
DEFINE(SVC_DACR, offsetof(struct svc_pt_regs, dacr));
DEFINE(SVC_TTBCR, offsetof(struct svc_pt_regs, ttbcr));
DEFINE(SVC_REGS_SIZE, sizeof(struct svc_pt_regs));
BLANK();
DEFINE(SIGFRAME_RC3_OFFSET, offsetof(struct sigframe, retcode[3]));
DEFINE(RT_SIGFRAME_RC3_OFFSET, offsetof(struct rt_sigframe, sig.retcode[3]));
BLANK();
#ifdef CONFIG_CACHE_L2X0
DEFINE(L2X0_R_PHY_BASE, offsetof(struct l2x0_regs, phy_base));
DEFINE(L2X0_R_AUX_CTRL, offsetof(struct l2x0_regs, aux_ctrl));
DEFINE(L2X0_R_TAG_LATENCY, offsetof(struct l2x0_regs, tag_latency));
DEFINE(L2X0_R_DATA_LATENCY, offsetof(struct l2x0_regs, data_latency));
DEFINE(L2X0_R_FILTER_START, offsetof(struct l2x0_regs, filter_start));
DEFINE(L2X0_R_FILTER_END, offsetof(struct l2x0_regs, filter_end));
DEFINE(L2X0_R_PREFETCH_CTRL, offsetof(struct l2x0_regs, prefetch_ctrl));
DEFINE(L2X0_R_PWR_CTRL, offsetof(struct l2x0_regs, pwr_ctrl));
BLANK();
#endif
#ifdef CONFIG_CPU_HAS_ASID
DEFINE(MM_CONTEXT_ID, offsetof(struct mm_struct, context.id.counter));
BLANK();
#endif
DEFINE(VMA_VM_MM, offsetof(struct vm_area_struct, vm_mm));
DEFINE(VMA_VM_FLAGS, offsetof(struct vm_area_struct, vm_flags));
BLANK();
DEFINE(VM_EXEC, VM_EXEC);
BLANK();
DEFINE(PAGE_SZ, PAGE_SIZE);
BLANK();
DEFINE(SYS_ERROR0, 0x9f0000);
BLANK();
DEFINE(SIZEOF_MACHINE_DESC, sizeof(struct machine_desc));
DEFINE(MACHINFO_TYPE, offsetof(struct machine_desc, nr));
DEFINE(MACHINFO_NAME, offsetof(struct machine_desc, name));
BLANK();
DEFINE(PROC_INFO_SZ, sizeof(struct proc_info_list));
DEFINE(PROCINFO_INITFUNC, offsetof(struct proc_info_list, __cpu_flush));
DEFINE(PROCINFO_MM_MMUFLAGS, offsetof(struct proc_info_list, __cpu_mm_mmu_flags));
DEFINE(PROCINFO_IO_MMUFLAGS, offsetof(struct proc_info_list, __cpu_io_mmu_flags));
BLANK();
#ifdef MULTI_DABORT
DEFINE(PROCESSOR_DABT_FUNC, offsetof(struct processor, _data_abort));
#endif
#ifdef MULTI_PABORT
DEFINE(PROCESSOR_PABT_FUNC, offsetof(struct processor, _prefetch_abort));
#endif
#ifdef MULTI_CPU
DEFINE(CPU_SLEEP_SIZE, offsetof(struct processor, suspend_size));
DEFINE(CPU_DO_SUSPEND, offsetof(struct processor, do_suspend));
DEFINE(CPU_DO_RESUME, offsetof(struct processor, do_resume));
#endif
#ifdef MULTI_CACHE
DEFINE(CACHE_FLUSH_KERN_ALL, offsetof(struct cpu_cache_fns, flush_kern_all));
#endif
#ifdef CONFIG_ARM_CPU_SUSPEND
DEFINE(SLEEP_SAVE_SP_SZ, sizeof(struct sleep_save_sp));
DEFINE(SLEEP_SAVE_SP_PHYS, offsetof(struct sleep_save_sp, save_ptr_stash_phys));
DEFINE(SLEEP_SAVE_SP_VIRT, offsetof(struct sleep_save_sp, save_ptr_stash));
#endif
DEFINE(ARM_SMCCC_QUIRK_ID_OFFS, offsetof(struct arm_smccc_quirk, id));
DEFINE(ARM_SMCCC_QUIRK_STATE_OFFS, offsetof(struct arm_smccc_quirk, state));
BLANK();
DEFINE(DMA_BIDIRECTIONAL, DMA_BIDIRECTIONAL);
DEFINE(DMA_TO_DEVICE, DMA_TO_DEVICE);
DEFINE(DMA_FROM_DEVICE, DMA_FROM_DEVICE);
BLANK();
DEFINE(CACHE_WRITEBACK_ORDER, __CACHE_WRITEBACK_ORDER);
DEFINE(CACHE_WRITEBACK_GRANULE, __CACHE_WRITEBACK_GRANULE);
BLANK();
#ifdef CONFIG_VDSO
DEFINE(VDSO_DATA_SIZE, sizeof(union vdso_data_store));
#endif
BLANK();
#ifdef CONFIG_ARM_MPU
DEFINE(MPU_RNG_INFO_RNGS, offsetof(struct mpu_rgn_info, rgns));
DEFINE(MPU_RNG_INFO_USED, offsetof(struct mpu_rgn_info, used));
DEFINE(MPU_RNG_SIZE, sizeof(struct mpu_rgn));
DEFINE(MPU_RGN_DRBAR, offsetof(struct mpu_rgn, drbar));
DEFINE(MPU_RGN_DRSR, offsetof(struct mpu_rgn, drsr));
DEFINE(MPU_RGN_DRACR, offsetof(struct mpu_rgn, dracr));
DEFINE(MPU_RGN_PRBAR, offsetof(struct mpu_rgn, prbar));
DEFINE(MPU_RGN_PRLAR, offsetof(struct mpu_rgn, prlar));
#endif
DEFINE(KEXEC_START_ADDR, offsetof(struct kexec_relocate_data, kexec_start_address));
DEFINE(KEXEC_INDIR_PAGE, offsetof(struct kexec_relocate_data, kexec_indirection_page));
DEFINE(KEXEC_MACH_TYPE, offsetof(struct kexec_relocate_data, kexec_mach_type));
DEFINE(KEXEC_R2, offsetof(struct kexec_relocate_data, kexec_r2));
return 0;
}