diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index a7f8e7f4b88f..55a609e9f797 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1704,6 +1704,7 @@ config ARCH_WANT_GENERAL_HUGETLB config ARM_MODULE_PLTS bool "Use PLTs to allow module memory to spill over into vmalloc area" depends on MODULES + default y help Allocate PLTs when loading modules so that jumps and calls whose targets are too far away for their relative offsets to be encoded @@ -1714,7 +1715,8 @@ config ARM_MODULE_PLTS rounding up to page size, the actual memory footprint is usually the same. - Say y if you are getting out of memory errors while loading modules + Disabling this is usually safe for small single-platform + configurations. If unsure, say y. source "mm/Kconfig" diff --git a/arch/arm/Makefile b/arch/arm/Makefile index e4e537f27339..0c2c00a41814 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -106,7 +106,7 @@ tune-$(CONFIG_CPU_V6K) =$(call cc-option,-mtune=arm1136j-s,-mtune=strongarm) tune-y := $(tune-y) ifeq ($(CONFIG_AEABI),y) -CFLAGS_ABI :=-mabi=aapcs-linux -mno-thumb-interwork -mfpu=vfp +CFLAGS_ABI :=-mabi=aapcs-linux -mfpu=vfp else CFLAGS_ABI :=$(call cc-option,-mapcs-32,-mabi=apcs-gnu) $(call cc-option,-mno-thumb-interwork,) endif diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 6a4e7341ecd3..a3c5fbcad4ab 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -113,7 +113,7 @@ CFLAGS_fdt_ro.o := $(nossp_flags) CFLAGS_fdt_rw.o := $(nossp_flags) CFLAGS_fdt_wip.o := $(nossp_flags) -ccflags-y := -fpic -mno-single-pic-base -fno-builtin -I$(obj) +ccflags-y := -fpic $(call cc-option,-mno-single-pic-base,) -fno-builtin -I$(obj) asflags-y := -DZIMAGE # Supply kernel BSS size to the decompressor via a linker symbol. diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 9342904cccca..0cd4dccbae78 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -447,6 +447,14 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) .size \name , . - \name .endm + .macro csdb +#ifdef CONFIG_THUMB2_KERNEL + .inst.w 0xf3af8014 +#else + .inst 0xe320f014 +#endif + .endm + .macro check_uaccess, addr:req, size:req, limit:req, tmp:req, bad:req #ifndef CONFIG_CPU_USE_DOMAINS adds \tmp, \addr, #\size - 1 diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h index 40f5c410fd8c..69772e742a0a 100644 --- a/arch/arm/include/asm/barrier.h +++ b/arch/arm/include/asm/barrier.h @@ -17,6 +17,12 @@ #define isb(option) __asm__ __volatile__ ("isb " #option : : : "memory") #define dsb(option) __asm__ __volatile__ ("dsb " #option : : : "memory") #define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory") +#ifdef CONFIG_THUMB2_KERNEL +#define CSDB ".inst.w 0xf3af8014" +#else +#define CSDB ".inst 0xe320f014" +#endif +#define csdb() __asm__ __volatile__(CSDB : : : "memory") #elif defined(CONFIG_CPU_XSC3) || __LINUX_ARM_ARCH__ == 6 #define isb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \ : : "r" (0) : "memory") @@ -37,6 +43,13 @@ #define dmb(x) __asm__ __volatile__ ("" : : : "memory") #endif +#ifndef CSDB +#define CSDB +#endif +#ifndef csdb +#define csdb() +#endif + #ifdef CONFIG_ARM_HEAVY_MB extern void (*soc_mb)(void); extern void arm_heavy_mb(void); @@ -63,6 +76,25 @@ extern void arm_heavy_mb(void); #define __smp_rmb() __smp_mb() #define __smp_wmb() dmb(ishst) +#ifdef CONFIG_CPU_SPECTRE +static inline unsigned long array_index_mask_nospec(unsigned long idx, + unsigned long sz) +{ + unsigned long mask; + + asm volatile( + "cmp %1, %2\n" + " sbc %0, %1, %1\n" + CSDB + : "=r" (mask) + : "r" (idx), "Ir" (sz) + : "cc"); + + return mask; +} +#define array_index_mask_nospec array_index_mask_nospec +#endif + #include #endif /* !__ASSEMBLY__ */ diff --git a/arch/arm/include/asm/bugs.h b/arch/arm/include/asm/bugs.h index a97f1ea708d1..73a99c72a930 100644 --- a/arch/arm/include/asm/bugs.h +++ b/arch/arm/include/asm/bugs.h @@ -10,12 +10,14 @@ #ifndef __ASM_BUGS_H #define __ASM_BUGS_H -#ifdef CONFIG_MMU extern void check_writebuffer_bugs(void); -#define check_bugs() check_writebuffer_bugs() +#ifdef CONFIG_MMU +extern void check_bugs(void); +extern void check_other_bugs(void); #else #define check_bugs() do { } while (0) +#define check_other_bugs() do { } while (0) #endif #endif diff --git a/arch/arm/include/asm/cp15.h b/arch/arm/include/asm/cp15.h index 4c9fa72b59f5..07e27f212dc7 100644 --- a/arch/arm/include/asm/cp15.h +++ b/arch/arm/include/asm/cp15.h @@ -65,6 +65,9 @@ #define __write_sysreg(v, r, w, c, t) asm volatile(w " " c : : "r" ((t)(v))) #define write_sysreg(v, ...) __write_sysreg(v, __VA_ARGS__) +#define BPIALL __ACCESS_CP15(c7, 0, c5, 6) +#define ICIALLU __ACCESS_CP15(c7, 0, c5, 0) + extern unsigned long cr_alignment; /* defined in entry-armv.S */ static inline unsigned long get_cr(void) diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index cb546425da8a..26021980504d 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h @@ -77,8 +77,16 @@ #define ARM_CPU_PART_CORTEX_A12 0x4100c0d0 #define ARM_CPU_PART_CORTEX_A17 0x4100c0e0 #define ARM_CPU_PART_CORTEX_A15 0x4100c0f0 +#define ARM_CPU_PART_CORTEX_A53 0x4100d030 +#define ARM_CPU_PART_CORTEX_A57 0x4100d070 +#define ARM_CPU_PART_CORTEX_A72 0x4100d080 +#define ARM_CPU_PART_CORTEX_A73 0x4100d090 +#define ARM_CPU_PART_CORTEX_A75 0x4100d0a0 #define ARM_CPU_PART_MASK 0xff00fff0 +/* Broadcom cores */ +#define ARM_CPU_PART_BRAHMA_B15 0x420000f0 + /* DEC implemented cores */ #define ARM_CPU_PART_SA1100 0x4400a110 diff --git a/arch/arm/include/asm/kgdb.h b/arch/arm/include/asm/kgdb.h index 3b73fdcf3627..8de1100d1067 100644 --- a/arch/arm/include/asm/kgdb.h +++ b/arch/arm/include/asm/kgdb.h @@ -77,7 +77,7 @@ extern int kgdb_fault_expected; #define KGDB_MAX_NO_CPUS 1 #define BUFMAX 400 -#define NUMREGBYTES (DBG_MAX_REG_NUM << 2) +#define NUMREGBYTES (GDB_MAX_REGS << 2) #define NUMCRITREGBYTES (32 << 2) #define _R0 0 diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h index 5a953ecb0d78..231e87ad45d5 100644 --- a/arch/arm/include/asm/kvm_asm.h +++ b/arch/arm/include/asm/kvm_asm.h @@ -61,8 +61,6 @@ struct kvm_vcpu; extern char __kvm_hyp_init[]; extern char __kvm_hyp_init_end[]; -extern char __kvm_hyp_vector[]; - extern void __kvm_flush_vm_context(void); extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa); extern void __kvm_tlb_flush_vmid(struct kvm *kvm); diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index c6a749568dd6..8467e05360d7 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -21,6 +21,7 @@ #include #include +#include #include #include #include @@ -308,8 +309,17 @@ static inline void kvm_arm_vhe_guest_exit(void) {} static inline bool kvm_arm_harden_branch_predictor(void) { - /* No way to detect it yet, pretend it is not there. */ - return false; + switch(read_cpuid_part()) { +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + case ARM_CPU_PART_BRAHMA_B15: + case ARM_CPU_PART_CORTEX_A12: + case ARM_CPU_PART_CORTEX_A15: + case ARM_CPU_PART_CORTEX_A17: + return true; +#endif + default: + return false; + } } static inline void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu) {} diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 707a1f06dc5d..cf2eae51f9a0 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -311,7 +311,28 @@ static inline unsigned int kvm_get_vmid_bits(void) static inline void *kvm_get_hyp_vector(void) { - return kvm_ksym_ref(__kvm_hyp_vector); + switch(read_cpuid_part()) { +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + case ARM_CPU_PART_CORTEX_A12: + case ARM_CPU_PART_CORTEX_A17: + { + extern char __kvm_hyp_vector_bp_inv[]; + return kvm_ksym_ref(__kvm_hyp_vector_bp_inv); + } + + case ARM_CPU_PART_BRAHMA_B15: + case ARM_CPU_PART_CORTEX_A15: + { + extern char __kvm_hyp_vector_ic_inv[]; + return kvm_ksym_ref(__kvm_hyp_vector_ic_inv); + } +#endif + default: + { + extern char __kvm_hyp_vector[]; + return kvm_ksym_ref(__kvm_hyp_vector); + } + } } static inline int kvm_map_vectors(void) diff --git a/arch/arm/include/asm/mpu.h b/arch/arm/include/asm/mpu.h index 6d1491c8ee22..5e088c83d3d8 100644 --- a/arch/arm/include/asm/mpu.h +++ b/arch/arm/include/asm/mpu.h @@ -12,60 +12,101 @@ /* ID_MMFR0 data relevant to MPU */ #define MMFR0_PMSA (0xF << 4) #define MMFR0_PMSAv7 (3 << 4) +#define MMFR0_PMSAv8 (4 << 4) /* MPU D/I Size Register fields */ -#define MPU_RSR_SZ 1 -#define MPU_RSR_EN 0 -#define MPU_RSR_SD 8 +#define PMSAv7_RSR_SZ 1 +#define PMSAv7_RSR_EN 0 +#define PMSAv7_RSR_SD 8 /* Number of subregions (SD) */ -#define MPU_NR_SUBREGS 8 -#define MPU_MIN_SUBREG_SIZE 256 +#define PMSAv7_NR_SUBREGS 8 +#define PMSAv7_MIN_SUBREG_SIZE 256 /* The D/I RSR value for an enabled region spanning the whole of memory */ -#define MPU_RSR_ALL_MEM 63 +#define PMSAv7_RSR_ALL_MEM 63 /* Individual bits in the DR/IR ACR */ -#define MPU_ACR_XN (1 << 12) -#define MPU_ACR_SHARED (1 << 2) +#define PMSAv7_ACR_XN (1 << 12) +#define PMSAv7_ACR_SHARED (1 << 2) /* C, B and TEX[2:0] bits only have semantic meanings when grouped */ -#define MPU_RGN_CACHEABLE 0xB -#define MPU_RGN_SHARED_CACHEABLE (MPU_RGN_CACHEABLE | MPU_ACR_SHARED) -#define MPU_RGN_STRONGLY_ORDERED 0 +#define PMSAv7_RGN_CACHEABLE 0xB +#define PMSAv7_RGN_SHARED_CACHEABLE (PMSAv7_RGN_CACHEABLE | PMSAv7_ACR_SHARED) +#define PMSAv7_RGN_STRONGLY_ORDERED 0 /* Main region should only be shared for SMP */ #ifdef CONFIG_SMP -#define MPU_RGN_NORMAL (MPU_RGN_CACHEABLE | MPU_ACR_SHARED) +#define PMSAv7_RGN_NORMAL (PMSAv7_RGN_CACHEABLE | PMSAv7_ACR_SHARED) #else -#define MPU_RGN_NORMAL MPU_RGN_CACHEABLE +#define PMSAv7_RGN_NORMAL PMSAv7_RGN_CACHEABLE #endif /* Access permission bits of ACR (only define those that we use)*/ -#define MPU_AP_PL1RO_PL0NA (0x5 << 8) -#define MPU_AP_PL1RW_PL0RW (0x3 << 8) -#define MPU_AP_PL1RW_PL0R0 (0x2 << 8) -#define MPU_AP_PL1RW_PL0NA (0x1 << 8) +#define PMSAv7_AP_PL1RO_PL0NA (0x5 << 8) +#define PMSAv7_AP_PL1RW_PL0RW (0x3 << 8) +#define PMSAv7_AP_PL1RW_PL0R0 (0x2 << 8) +#define PMSAv7_AP_PL1RW_PL0NA (0x1 << 8) + +#define PMSAv8_BAR_XN 1 + +#define PMSAv8_LAR_EN 1 +#define PMSAv8_LAR_IDX(n) (((n) & 0x7) << 1) + + +#define PMSAv8_AP_PL1RW_PL0NA (0 << 1) +#define PMSAv8_AP_PL1RW_PL0RW (1 << 1) +#define PMSAv8_AP_PL1RO_PL0RO (3 << 1) + +#ifdef CONFIG_SMP +#define PMSAv8_RGN_SHARED (3 << 3) // inner sharable +#else +#define PMSAv8_RGN_SHARED (0 << 3) +#endif + +#define PMSAv8_RGN_DEVICE_nGnRnE 0 +#define PMSAv8_RGN_NORMAL 1 + +#define PMSAv8_MAIR(attr, mt) ((attr) << ((mt) * 8)) + +#ifdef CONFIG_CPU_V7M +#define PMSAv8_MINALIGN 32 +#else +#define PMSAv8_MINALIGN 64 +#endif /* For minimal static MPU region configurations */ -#define MPU_PROBE_REGION 0 -#define MPU_BG_REGION 1 -#define MPU_RAM_REGION 2 -#define MPU_ROM_REGION 3 +#define PMSAv7_PROBE_REGION 0 +#define PMSAv7_BG_REGION 1 +#define PMSAv7_RAM_REGION 2 +#define PMSAv7_ROM_REGION 3 + +/* Fixed for PMSAv8 only */ +#define PMSAv8_XIP_REGION 0 +#define PMSAv8_KERNEL_REGION 1 /* Maximum number of regions Linux is interested in */ -#define MPU_MAX_REGIONS 16 +#define MPU_MAX_REGIONS 16 -#define MPU_DATA_SIDE 0 -#define MPU_INSTR_SIDE 1 +#define PMSAv7_DATA_SIDE 0 +#define PMSAv7_INSTR_SIDE 1 #ifndef __ASSEMBLY__ struct mpu_rgn { /* Assume same attributes for d/i-side */ - u32 drbar; - u32 drsr; - u32 dracr; + union { + u32 drbar; /* PMSAv7 */ + u32 prbar; /* PMSAv8 */ + }; + union { + u32 drsr; /* PMSAv7 */ + u32 prlar; /* PMSAv8 */ + }; + union { + u32 dracr; /* PMSAv7 */ + u32 unused; /* not used in PMSAv8 */ + }; }; struct mpu_rgn_info { @@ -75,16 +116,17 @@ struct mpu_rgn_info { extern struct mpu_rgn_info mpu_rgn_info; #ifdef CONFIG_ARM_MPU +extern void __init pmsav7_adjust_lowmem_bounds(void); +extern void __init pmsav8_adjust_lowmem_bounds(void); -extern void __init adjust_lowmem_bounds_mpu(void); -extern void __init mpu_setup(void); - +extern void __init pmsav7_setup(void); +extern void __init pmsav8_setup(void); #else - -static inline void adjust_lowmem_bounds_mpu(void) {} -static inline void mpu_setup(void) {} - -#endif /* !CONFIG_ARM_MPU */ +static inline void pmsav7_adjust_lowmem_bounds(void) {}; +static inline void pmsav8_adjust_lowmem_bounds(void) {}; +static inline void pmsav7_setup(void) {}; +static inline void pmsav8_setup(void) {}; +#endif #endif /* __ASSEMBLY__ */ diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h index f2e1af45bd6f..e25f4392e1b2 100644 --- a/arch/arm/include/asm/proc-fns.h +++ b/arch/arm/include/asm/proc-fns.h @@ -36,6 +36,10 @@ extern struct processor { * Set up any processor specifics */ void (*_proc_init)(void); + /* + * Check for processor bugs + */ + void (*check_bugs)(void); /* * Disable any processor specifics */ diff --git a/arch/arm/include/asm/system_misc.h b/arch/arm/include/asm/system_misc.h index 78f6db114faf..8e76db83c498 100644 --- a/arch/arm/include/asm/system_misc.h +++ b/arch/arm/include/asm/system_misc.h @@ -8,6 +8,7 @@ #include #include #include +#include extern void cpu_init(void); @@ -15,6 +16,20 @@ void soft_restart(unsigned long); extern void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd); extern void (*arm_pm_idle)(void); +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR +typedef void (*harden_branch_predictor_fn_t)(void); +DECLARE_PER_CPU(harden_branch_predictor_fn_t, harden_branch_predictor_fn); +static inline void harden_branch_predictor(void) +{ + harden_branch_predictor_fn_t fn = per_cpu(harden_branch_predictor_fn, + smp_processor_id()); + if (fn) + fn(); +} +#else +#define harden_branch_predictor() do { } while (0) +#endif + #define UDBG_UNDEFINED (1 << 0) #define UDBG_SYSCALL (1 << 1) #define UDBG_BADABORT (1 << 2) diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 0bf2347495f1..3d614e90c19f 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -152,7 +152,7 @@ extern int __get_user_64t_4(void *); #define __get_user_check(x, p) \ ({ \ unsigned long __limit = current_thread_info()->addr_limit - 1; \ - register const typeof(*(p)) __user *__p asm("r0") = (p);\ + register typeof(*(p)) __user *__p asm("r0") = (p); \ register typeof(x) __r2 asm("r2"); \ register unsigned long __l asm("r1") = __limit; \ register int __e asm("r0"); \ diff --git a/arch/arm/include/asm/v7m.h b/arch/arm/include/asm/v7m.h index 634e77107425..187ccf6496ad 100644 --- a/arch/arm/include/asm/v7m.h +++ b/arch/arm/include/asm/v7m.h @@ -64,9 +64,17 @@ #define MPU_CTRL_ENABLE 1 #define MPU_CTRL_PRIVDEFENA (1 << 2) -#define MPU_RNR 0x98 -#define MPU_RBAR 0x9c -#define MPU_RASR 0xa0 +#define PMSAv7_RNR 0x98 +#define PMSAv7_RBAR 0x9c +#define PMSAv7_RASR 0xa0 + +#define PMSAv8_RNR 0x98 +#define PMSAv8_RBAR 0x9c +#define PMSAv8_RLAR 0xa0 +#define PMSAv8_RBAR_A(n) (PMSAv8_RBAR + 8*(n)) +#define PMSAv8_RLAR_A(n) (PMSAv8_RLAR + 8*(n)) +#define PMSAv8_MAIR0 0xc0 +#define PMSAv8_MAIR1 0xc4 /* Cache opeartions */ #define V7M_SCB_ICIALLU 0x250 /* I-cache invalidate all to PoU */ diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index b59ac4bf82b8..8cad59465af3 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -31,6 +31,7 @@ else obj-y += entry-armv.o endif +obj-$(CONFIG_MMU) += bugs.o obj-$(CONFIG_CPU_IDLE) += cpuidle.o obj-$(CONFIG_ISA_DMA_API) += dma.o obj-$(CONFIG_FIQ) += fiq.o fiqasm.o diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index f369ece99958..27c5381518d8 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -194,9 +194,11 @@ int main(void) 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_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 return 0; } diff --git a/arch/arm/kernel/bugs.c b/arch/arm/kernel/bugs.c new file mode 100644 index 000000000000..7be511310191 --- /dev/null +++ b/arch/arm/kernel/bugs.c @@ -0,0 +1,18 @@ +// SPDX-Identifier: GPL-2.0 +#include +#include +#include + +void check_other_bugs(void) +{ +#ifdef MULTI_CPU + if (processor.check_bugs) + processor.check_bugs(); +#endif +} + +void __init check_bugs(void) +{ + check_writebuffer_bugs(); + check_other_bugs(); +} diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 3c4f88701f22..20df608bf343 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -242,9 +242,7 @@ local_restart: tst r10, #_TIF_SYSCALL_WORK @ are we tracing syscalls? bne __sys_trace - cmp scno, #NR_syscalls @ check upper syscall limit - badr lr, ret_fast_syscall @ return address - ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine + invoke_syscall tbl, scno, r10, ret_fast_syscall add r1, sp, #S_OFF 2: cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE) @@ -278,14 +276,8 @@ __sys_trace: mov r1, scno add r0, sp, #S_OFF bl syscall_trace_enter - - badr lr, __sys_trace_return @ return address - mov scno, r0 @ syscall number (possibly new) - add r1, sp, #S_R0 + S_OFF @ pointer to regs - cmp scno, #NR_syscalls @ check upper syscall limit - ldmccia r1, {r0 - r6} @ have to reload r0 - r6 - stmccia sp, {r4, r5} @ and update the stack args - ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine + mov scno, r0 + invoke_syscall tbl, scno, r10, __sys_trace_return, reload=1 cmp scno, #-1 @ skip the syscall? bne 2b add sp, sp, #S_OFF @ restore stack @@ -363,6 +355,10 @@ sys_syscall: bic scno, r0, #__NR_OABI_SYSCALL_BASE cmp scno, #__NR_syscall - __NR_SYSCALL_BASE cmpne scno, #NR_syscalls @ check range +#ifdef CONFIG_CPU_SPECTRE + movhs scno, #0 + csdb +#endif stmloia sp, {r5, r6} @ shuffle args movlo r0, r1 movlo r1, r2 diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S index 0f07579af472..773424843d6e 100644 --- a/arch/arm/kernel/entry-header.S +++ b/arch/arm/kernel/entry-header.S @@ -378,6 +378,31 @@ #endif .endm + .macro invoke_syscall, table, nr, tmp, ret, reload=0 +#ifdef CONFIG_CPU_SPECTRE + mov \tmp, \nr + cmp \tmp, #NR_syscalls @ check upper syscall limit + movcs \tmp, #0 + csdb + badr lr, \ret @ return address + .if \reload + add r1, sp, #S_R0 + S_OFF @ pointer to regs + ldmccia r1, {r0 - r6} @ reload r0-r6 + stmccia sp, {r4, r5} @ update stack arguments + .endif + ldrcc pc, [\table, \tmp, lsl #2] @ call sys_* routine +#else + cmp \nr, #NR_syscalls @ check upper syscall limit + badr lr, \ret @ return address + .if \reload + add r1, sp, #S_R0 + S_OFF @ pointer to regs + ldmccia r1, {r0 - r6} @ reload r0-r6 + stmccia sp, {r4, r5} @ update stack arguments + .endif + ldrcc pc, [\table, \nr, lsl #2] @ call sys_* routine +#endif + .endm + /* * These are the registers used in the syscall handler, and allow us to * have in theory up to 7 arguments to a function - r0 to r6. diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index 2e38f85b757a..dd546d65a383 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -68,14 +68,6 @@ ENTRY(stext) beq __error_p @ yes, error 'p' #ifdef CONFIG_ARM_MPU - /* Calculate the size of a region covering just the kernel */ - ldr r5, =PLAT_PHYS_OFFSET @ Region start: PHYS_OFFSET - ldr r6, =(_end) @ Cover whole kernel - sub r6, r6, r5 @ Minimum size of region to map - clz r6, r6 @ Region size must be 2^N... - rsb r6, r6, #31 @ ...so round up region size - lsl r6, r6, #MPU_RSR_SZ @ Put size in right field - orr r6, r6, #(1 << MPU_RSR_EN) @ Set region enabled bit bl __setup_mpu #endif @@ -83,8 +75,8 @@ ENTRY(stext) ldr r12, [r10, #PROCINFO_INITFUNC] add r12, r12, r10 ret r12 -1: bl __after_proc_init - b __mmap_switched +1: ldr lr, =__mmap_switched + b __after_proc_init ENDPROC(stext) #ifdef CONFIG_SMP @@ -110,8 +102,6 @@ ENTRY(secondary_startup) ldr r7, __secondary_data #ifdef CONFIG_ARM_MPU - /* Use MPU region info supplied by __cpu_up */ - ldr r6, [r7] @ get secondary_data.mpu_rgn_info bl __secondary_setup_mpu @ Initialize the MPU #endif @@ -133,12 +123,45 @@ __secondary_data: /* * Set the Control Register and Read the process ID. */ + .text __after_proc_init: +#ifdef CONFIG_ARM_MPU +M_CLASS(movw r12, #:lower16:BASEADDR_V7M_SCB) +M_CLASS(movt r12, #:upper16:BASEADDR_V7M_SCB) +M_CLASS(ldr r3, [r12, 0x50]) +AR_CLASS(mrc p15, 0, r3, c0, c1, 4) @ Read ID_MMFR0 + and r3, r3, #(MMFR0_PMSA) @ PMSA field + teq r3, #(MMFR0_PMSAv7) @ PMSA v7 + beq 1f + teq r3, #(MMFR0_PMSAv8) @ PMSA v8 + /* + * Memory region attributes for PMSAv8: + * + * n = AttrIndx[2:0] + * n MAIR + * DEVICE_nGnRnE 000 00000000 + * NORMAL 001 11111111 + */ + ldreq r3, =PMSAv8_MAIR(0x00, PMSAv8_RGN_DEVICE_nGnRnE) | \ + PMSAv8_MAIR(0xff, PMSAv8_RGN_NORMAL) +AR_CLASS(mcreq p15, 0, r3, c10, c2, 0) @ MAIR 0 +M_CLASS(streq r3, [r12, #PMSAv8_MAIR0]) + moveq r3, #0 +AR_CLASS(mcreq p15, 0, r3, c10, c2, 1) @ MAIR 1 +M_CLASS(streq r3, [r12, #PMSAv8_MAIR1]) + +1: +#endif #ifdef CONFIG_CPU_CP15 /* * CP15 system control register value returned in r0 from * the CPU init function. */ + +#ifdef CONFIG_ARM_MPU + biceq r0, r0, #CR_BR @ Disable the 'default mem-map' + orreq r0, r0, #CR_M @ Set SCTRL.M (MPU on) +#endif #if defined(CONFIG_ALIGNMENT_TRAP) && __LINUX_ARM_ARCH__ < 6 orr r0, r0, #CR_A #else @@ -154,7 +177,15 @@ __after_proc_init: bic r0, r0, #CR_I #endif mcr p15, 0, r0, c1, c0, 0 @ write control reg + isb #elif defined (CONFIG_CPU_V7M) +#ifdef CONFIG_ARM_MPU + ldreq r3, [r12, MPU_CTRL] + biceq r3, #MPU_CTRL_PRIVDEFENA + orreq r3, #MPU_CTRL_ENABLE + streq r3, [r12, MPU_CTRL] + isb +#endif /* For V7M systems we want to modify the CCR similarly to the SCTLR */ #ifdef CONFIG_CPU_DCACHE_DISABLE bic r0, r0, #V7M_SCB_CCR_DC @@ -165,9 +196,7 @@ __after_proc_init: #ifdef CONFIG_CPU_ICACHE_DISABLE bic r0, r0, #V7M_SCB_CCR_IC #endif - movw r3, #:lower16:(BASEADDR_V7M_SCB + V7M_SCB_CCR) - movt r3, #:upper16:(BASEADDR_V7M_SCB + V7M_SCB_CCR) - str r0, [r3] + str r0, [r12, V7M_SCB_CCR] #endif /* CONFIG_CPU_CP15 elif CONFIG_CPU_V7M */ ret lr ENDPROC(__after_proc_init) @@ -184,7 +213,7 @@ ENDPROC(__after_proc_init) .endm /* Setup a single MPU region, either D or I side (D-side for unified) */ -.macro setup_region bar, acr, sr, side = MPU_DATA_SIDE, unused +.macro setup_region bar, acr, sr, side = PMSAv7_DATA_SIDE, unused mcr p15, 0, \bar, c6, c1, (0 + \side) @ I/DRBAR mcr p15, 0, \acr, c6, c1, (4 + \side) @ I/DRACR mcr p15, 0, \sr, c6, c1, (2 + \side) @ I/DRSR @@ -192,14 +221,14 @@ ENDPROC(__after_proc_init) #else .macro set_region_nr tmp, rgnr, base mov \tmp, \rgnr - str \tmp, [\base, #MPU_RNR] + str \tmp, [\base, #PMSAv7_RNR] .endm .macro setup_region bar, acr, sr, unused, base lsl \acr, \acr, #16 orr \acr, \acr, \sr - str \bar, [\base, #MPU_RBAR] - str \acr, [\base, #MPU_RASR] + str \bar, [\base, #PMSAv7_RBAR] + str \acr, [\base, #PMSAv7_RASR] .endm #endif @@ -210,8 +239,9 @@ ENDPROC(__after_proc_init) * Region 2: Normal, Shared, cacheable for RAM. From PHYS_OFFSET, size from r6 * Region 3: Normal, shared, inaccessible from PL0 to protect the vectors page * - * r6: Value to be written to DRSR (and IRSR if required) for MPU_RAM_REGION + * r6: Value to be written to DRSR (and IRSR if required) for PMSAv7_RAM_REGION */ + __HEAD ENTRY(__setup_mpu) @@ -223,7 +253,22 @@ AR_CLASS(mrc p15, 0, r0, c0, c1, 4) @ Read ID_MMFR0 M_CLASS(ldr r0, [r12, 0x50]) and r0, r0, #(MMFR0_PMSA) @ PMSA field teq r0, #(MMFR0_PMSAv7) @ PMSA v7 - bxne lr + beq __setup_pmsa_v7 + teq r0, #(MMFR0_PMSAv8) @ PMSA v8 + beq __setup_pmsa_v8 + + ret lr +ENDPROC(__setup_mpu) + +ENTRY(__setup_pmsa_v7) + /* Calculate the size of a region covering just the kernel */ + ldr r5, =PLAT_PHYS_OFFSET @ Region start: PHYS_OFFSET + ldr r6, =(_end) @ Cover whole kernel + sub r6, r6, r5 @ Minimum size of region to map + clz r6, r6 @ Region size must be 2^N... + rsb r6, r6, #31 @ ...so round up region size + lsl r6, r6, #PMSAv7_RSR_SZ @ Put size in right field + orr r6, r6, #(1 << PMSAv7_RSR_EN) @ Set region enabled bit /* Determine whether the D/I-side memory map is unified. We set the * flags here and continue to use them for the rest of this function */ @@ -234,77 +279,189 @@ M_CLASS(ldr r0, [r12, #MPU_TYPE]) tst r0, #MPUIR_nU @ MPUIR_nU = 0 for unified /* Setup second region first to free up r6 */ - set_region_nr r0, #MPU_RAM_REGION, r12 + set_region_nr r0, #PMSAv7_RAM_REGION, r12 isb /* Full access from PL0, PL1, shared for CONFIG_SMP, cacheable */ ldr r0, =PLAT_PHYS_OFFSET @ RAM starts at PHYS_OFFSET - ldr r5,=(MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL) + ldr r5,=(PMSAv7_AP_PL1RW_PL0RW | PMSAv7_RGN_NORMAL) - setup_region r0, r5, r6, MPU_DATA_SIDE, r12 @ PHYS_OFFSET, shared, enabled + setup_region r0, r5, r6, PMSAv7_DATA_SIDE, r12 @ PHYS_OFFSET, shared, enabled beq 1f @ Memory-map not unified - setup_region r0, r5, r6, MPU_INSTR_SIDE, r12 @ PHYS_OFFSET, shared, enabled + setup_region r0, r5, r6, PMSAv7_INSTR_SIDE, r12 @ PHYS_OFFSET, shared, enabled 1: isb /* First/background region */ - set_region_nr r0, #MPU_BG_REGION, r12 + set_region_nr r0, #PMSAv7_BG_REGION, r12 isb /* Execute Never, strongly ordered, inaccessible to PL0, rw PL1 */ mov r0, #0 @ BG region starts at 0x0 - ldr r5,=(MPU_ACR_XN | MPU_RGN_STRONGLY_ORDERED | MPU_AP_PL1RW_PL0NA) - mov r6, #MPU_RSR_ALL_MEM @ 4GB region, enabled + ldr r5,=(PMSAv7_ACR_XN | PMSAv7_RGN_STRONGLY_ORDERED | PMSAv7_AP_PL1RW_PL0NA) + mov r6, #PMSAv7_RSR_ALL_MEM @ 4GB region, enabled - setup_region r0, r5, r6, MPU_DATA_SIDE, r12 @ 0x0, BG region, enabled + setup_region r0, r5, r6, PMSAv7_DATA_SIDE, r12 @ 0x0, BG region, enabled beq 2f @ Memory-map not unified - setup_region r0, r5, r6, MPU_INSTR_SIDE r12 @ 0x0, BG region, enabled + setup_region r0, r5, r6, PMSAv7_INSTR_SIDE r12 @ 0x0, BG region, enabled 2: isb #ifdef CONFIG_XIP_KERNEL - set_region_nr r0, #MPU_ROM_REGION, r12 + set_region_nr r0, #PMSAv7_ROM_REGION, r12 isb - ldr r5,=(MPU_AP_PL1RO_PL0NA | MPU_RGN_NORMAL) + ldr r5,=(PMSAv7_AP_PL1RO_PL0NA | PMSAv7_RGN_NORMAL) ldr r0, =CONFIG_XIP_PHYS_ADDR @ ROM start ldr r6, =(_exiprom) @ ROM end sub r6, r6, r0 @ Minimum size of region to map clz r6, r6 @ Region size must be 2^N... rsb r6, r6, #31 @ ...so round up region size - lsl r6, r6, #MPU_RSR_SZ @ Put size in right field - orr r6, r6, #(1 << MPU_RSR_EN) @ Set region enabled bit + lsl r6, r6, #PMSAv7_RSR_SZ @ Put size in right field + orr r6, r6, #(1 << PMSAv7_RSR_EN) @ Set region enabled bit - setup_region r0, r5, r6, MPU_DATA_SIDE, r12 @ XIP_PHYS_ADDR, shared, enabled + setup_region r0, r5, r6, PMSAv7_DATA_SIDE, r12 @ XIP_PHYS_ADDR, shared, enabled beq 3f @ Memory-map not unified - setup_region r0, r5, r6, MPU_INSTR_SIDE, r12 @ XIP_PHYS_ADDR, shared, enabled + setup_region r0, r5, r6, PMSAv7_INSTR_SIDE, r12 @ XIP_PHYS_ADDR, shared, enabled 3: isb #endif + ret lr +ENDPROC(__setup_pmsa_v7) - /* Enable the MPU */ -AR_CLASS(mrc p15, 0, r0, c1, c0, 0) @ Read SCTLR -AR_CLASS(bic r0, r0, #CR_BR) @ Disable the 'default mem-map' -AR_CLASS(orr r0, r0, #CR_M) @ Set SCTRL.M (MPU on) -AR_CLASS(mcr p15, 0, r0, c1, c0, 0) @ Enable MPU - -M_CLASS(ldr r0, [r12, #MPU_CTRL]) -M_CLASS(bic r0, #MPU_CTRL_PRIVDEFENA) -M_CLASS(orr r0, #MPU_CTRL_ENABLE) -M_CLASS(str r0, [r12, #MPU_CTRL]) +ENTRY(__setup_pmsa_v8) + mov r0, #0 +AR_CLASS(mcr p15, 0, r0, c6, c2, 1) @ PRSEL +M_CLASS(str r0, [r12, #PMSAv8_RNR]) isb +#ifdef CONFIG_XIP_KERNEL + ldr r5, =CONFIG_XIP_PHYS_ADDR @ ROM start + ldr r6, =(_exiprom) @ ROM end + sub r6, r6, #1 + bic r6, r6, #(PMSAv8_MINALIGN - 1) + + orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED) + orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN) + +AR_CLASS(mcr p15, 0, r5, c6, c8, 0) @ PRBAR0 +AR_CLASS(mcr p15, 0, r6, c6, c8, 1) @ PRLAR0 +M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(0)]) +M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(0)]) +#endif + + ldr r5, =KERNEL_START + ldr r6, =KERNEL_END + sub r6, r6, #1 + bic r6, r6, #(PMSAv8_MINALIGN - 1) + + orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED) + orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN) + +AR_CLASS(mcr p15, 0, r5, c6, c8, 4) @ PRBAR1 +AR_CLASS(mcr p15, 0, r6, c6, c8, 5) @ PRLAR1 +M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(1)]) +M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(1)]) + + /* Setup Background: 0x0 - min(KERNEL_START, XIP_PHYS_ADDR) */ +#ifdef CONFIG_XIP_KERNEL + ldr r6, =KERNEL_START + ldr r5, =CONFIG_XIP_PHYS_ADDR + cmp r6, r5 + movcs r6, r5 +#else + ldr r6, =KERNEL_START +#endif + cmp r6, #0 + beq 1f + + mov r5, #0 + sub r6, r6, #1 + bic r6, r6, #(PMSAv8_MINALIGN - 1) + + orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN) + orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN) + +AR_CLASS(mcr p15, 0, r5, c6, c9, 0) @ PRBAR2 +AR_CLASS(mcr p15, 0, r6, c6, c9, 1) @ PRLAR2 +M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(2)]) +M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(2)]) + +1: + /* Setup Background: max(KERNEL_END, _exiprom) - 0xffffffff */ +#ifdef CONFIG_XIP_KERNEL + ldr r5, =KERNEL_END + ldr r6, =(_exiprom) + cmp r5, r6 + movcc r5, r6 +#else + ldr r5, =KERNEL_END +#endif + mov r6, #0xffffffff + bic r6, r6, #(PMSAv8_MINALIGN - 1) + + orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN) + orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN) + +AR_CLASS(mcr p15, 0, r5, c6, c9, 4) @ PRBAR3 +AR_CLASS(mcr p15, 0, r6, c6, c9, 5) @ PRLAR3 +M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(3)]) +M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(3)]) + +#ifdef CONFIG_XIP_KERNEL + /* Setup Background: min(_exiprom, KERNEL_END) - max(KERNEL_START, XIP_PHYS_ADDR) */ + ldr r5, =(_exiprom) + ldr r6, =KERNEL_END + cmp r5, r6 + movcs r5, r6 + + ldr r6, =KERNEL_START + ldr r0, =CONFIG_XIP_PHYS_ADDR + cmp r6, r0 + movcc r6, r0 + + sub r6, r6, #1 + bic r6, r6, #(PMSAv8_MINALIGN - 1) + + orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN) + orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN) + +#ifdef CONFIG_CPU_V7M + /* There is no alias for n == 4 */ + mov r0, #4 + str r0, [r12, #PMSAv8_RNR] @ PRSEL + isb + + str r5, [r12, #PMSAv8_RBAR_A(0)] + str r6, [r12, #PMSAv8_RLAR_A(0)] +#else + mcr p15, 0, r5, c6, c10, 1 @ PRBAR4 + mcr p15, 0, r6, c6, c10, 2 @ PRLAR4 +#endif +#endif ret lr -ENDPROC(__setup_mpu) +ENDPROC(__setup_pmsa_v8) #ifdef CONFIG_SMP /* * r6: pointer at mpu_rgn_info */ + .text ENTRY(__secondary_setup_mpu) + /* Use MPU region info supplied by __cpu_up */ + ldr r6, [r7] @ get secondary_data.mpu_rgn_info + /* Probe for v7 PMSA compliance */ mrc p15, 0, r0, c0, c1, 4 @ Read ID_MMFR0 and r0, r0, #(MMFR0_PMSA) @ PMSA field teq r0, #(MMFR0_PMSAv7) @ PMSA v7 - bne __error_p + beq __secondary_setup_pmsa_v7 + teq r0, #(MMFR0_PMSAv8) @ PMSA v8 + beq __secondary_setup_pmsa_v8 + b __error_p +ENDPROC(__secondary_setup_mpu) +/* + * r6: pointer at mpu_rgn_info + */ +ENTRY(__secondary_setup_pmsa_v7) /* Determine whether the D/I-side memory map is unified. We set the * flags here and continue to use them for the rest of this function */ mrc p15, 0, r0, c0, c0, 4 @ MPUIR @@ -328,25 +485,45 @@ ENTRY(__secondary_setup_mpu) ldr r6, [r3, #MPU_RGN_DRSR] ldr r5, [r3, #MPU_RGN_DRACR] - setup_region r0, r5, r6, MPU_DATA_SIDE + setup_region r0, r5, r6, PMSAv7_DATA_SIDE beq 2f - setup_region r0, r5, r6, MPU_INSTR_SIDE + setup_region r0, r5, r6, PMSAv7_INSTR_SIDE 2: isb mrc p15, 0, r0, c0, c0, 4 @ Reevaluate the MPUIR cmp r4, #0 bgt 1b - /* Enable the MPU */ - mrc p15, 0, r0, c1, c0, 0 @ Read SCTLR - bic r0, r0, #CR_BR @ Disable the 'default mem-map' - orr r0, r0, #CR_M @ Set SCTRL.M (MPU on) - mcr p15, 0, r0, c1, c0, 0 @ Enable MPU + ret lr +ENDPROC(__secondary_setup_pmsa_v7) + +ENTRY(__secondary_setup_pmsa_v8) + ldr r4, [r6, #MPU_RNG_INFO_USED] +#ifndef CONFIG_XIP_KERNEL + add r4, r4, #1 +#endif + mov r5, #MPU_RNG_SIZE + add r3, r6, #MPU_RNG_INFO_RNGS + mla r3, r4, r5, r3 + +1: + sub r3, r3, #MPU_RNG_SIZE + sub r4, r4, #1 + + mcr p15, 0, r4, c6, c2, 1 @ PRSEL isb - ret lr -ENDPROC(__secondary_setup_mpu) + ldr r5, [r3, #MPU_RGN_PRBAR] + ldr r6, [r3, #MPU_RGN_PRLAR] + mcr p15, 0, r5, c6, c3, 0 @ PRBAR + mcr p15, 0, r6, c6, c3, 1 @ PRLAR + + cmp r4, #0 + bgt 1b + + ret lr +ENDPROC(__secondary_setup_pmsa_v8) #endif /* CONFIG_SMP */ #endif /* CONFIG_ARM_MPU */ #include "head-common.S" diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 2da087926ebe..0978282d5fc2 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -31,6 +31,7 @@ #include #include +#include #include #include #include @@ -236,8 +237,6 @@ int __cpu_disable(void) flush_cache_louis(); local_flush_tlb_all(); - clear_tasks_mm_cpumask(cpu); - return 0; } @@ -255,6 +254,7 @@ void __cpu_die(unsigned int cpu) } pr_debug("CPU%u: shutdown\n", cpu); + clear_tasks_mm_cpumask(cpu); /* * platform_cpu_kill() is generally expected to do the powering off * and/or cutting of clocks to the dying CPU. Optionally, this may @@ -405,6 +405,9 @@ asmlinkage void secondary_start_kernel(void) * before we continue - which happens after __cpu_up returns. */ set_cpu_online(cpu, true); + + check_other_bugs(); + complete(&cpu_running); local_irq_enable(); diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c index a40ebb7c0896..d08099269e35 100644 --- a/arch/arm/kernel/suspend.c +++ b/arch/arm/kernel/suspend.c @@ -3,6 +3,7 @@ #include #include +#include #include #include #include @@ -36,6 +37,7 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) cpu_switch_mm(mm->pgd, mm); local_flush_bp_all(); local_flush_tlb_all(); + check_other_bugs(); } return ret; diff --git a/arch/arm/kernel/vmlinux-xip.lds.S b/arch/arm/kernel/vmlinux-xip.lds.S index d32f5d35f602..3593d5c1acd2 100644 --- a/arch/arm/kernel/vmlinux-xip.lds.S +++ b/arch/arm/kernel/vmlinux-xip.lds.S @@ -13,6 +13,7 @@ #include #include #include +#include #include #include "vmlinux.lds.h" @@ -148,6 +149,9 @@ SECTIONS __init_end = .; BSS_SECTION(0, 0, 8) +#ifdef CONFIG_ARM_MPU + . = ALIGN(PMSAv8_MINALIGN); +#endif _end = .; STABS_DEBUG diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index b77dc675ae55..23150c0f0f4d 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -12,6 +12,7 @@ #include #include #include +#include #include #include @@ -54,6 +55,9 @@ SECTIONS . = ALIGN(1< #include #include #include @@ -71,6 +72,90 @@ __kvm_hyp_vector: W(b) hyp_irq W(b) hyp_fiq +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + .align 5 +__kvm_hyp_vector_ic_inv: + .global __kvm_hyp_vector_ic_inv + + /* + * We encode the exception entry in the bottom 3 bits of + * SP, and we have to guarantee to be 8 bytes aligned. + */ + W(add) sp, sp, #1 /* Reset 7 */ + W(add) sp, sp, #1 /* Undef 6 */ + W(add) sp, sp, #1 /* Syscall 5 */ + W(add) sp, sp, #1 /* Prefetch abort 4 */ + W(add) sp, sp, #1 /* Data abort 3 */ + W(add) sp, sp, #1 /* HVC 2 */ + W(add) sp, sp, #1 /* IRQ 1 */ + W(nop) /* FIQ 0 */ + + mcr p15, 0, r0, c7, c5, 0 /* ICIALLU */ + isb + + b decode_vectors + + .align 5 +__kvm_hyp_vector_bp_inv: + .global __kvm_hyp_vector_bp_inv + + /* + * We encode the exception entry in the bottom 3 bits of + * SP, and we have to guarantee to be 8 bytes aligned. + */ + W(add) sp, sp, #1 /* Reset 7 */ + W(add) sp, sp, #1 /* Undef 6 */ + W(add) sp, sp, #1 /* Syscall 5 */ + W(add) sp, sp, #1 /* Prefetch abort 4 */ + W(add) sp, sp, #1 /* Data abort 3 */ + W(add) sp, sp, #1 /* HVC 2 */ + W(add) sp, sp, #1 /* IRQ 1 */ + W(nop) /* FIQ 0 */ + + mcr p15, 0, r0, c7, c5, 6 /* BPIALL */ + isb + +decode_vectors: + +#ifdef CONFIG_THUMB2_KERNEL + /* + * Yet another silly hack: Use VPIDR as a temp register. + * Thumb2 is really a pain, as SP cannot be used with most + * of the bitwise instructions. The vect_br macro ensures + * things gets cleaned-up. + */ + mcr p15, 4, r0, c0, c0, 0 /* VPIDR */ + mov r0, sp + and r0, r0, #7 + sub sp, sp, r0 + push {r1, r2} + mov r1, r0 + mrc p15, 4, r0, c0, c0, 0 /* VPIDR */ + mrc p15, 0, r2, c0, c0, 0 /* MIDR */ + mcr p15, 4, r2, c0, c0, 0 /* VPIDR */ +#endif + +.macro vect_br val, targ +ARM( eor sp, sp, #\val ) +ARM( tst sp, #7 ) +ARM( eorne sp, sp, #\val ) + +THUMB( cmp r1, #\val ) +THUMB( popeq {r1, r2} ) + + beq \targ +.endm + + vect_br 0, hyp_fiq + vect_br 1, hyp_irq + vect_br 2, hyp_hvc + vect_br 3, hyp_dabt + vect_br 4, hyp_pabt + vect_br 5, hyp_svc + vect_br 6, hyp_undef + vect_br 7, hyp_reset +#endif + .macro invalid_vector label, cause .align \label: mov r0, #\cause @@ -118,7 +203,7 @@ hyp_hvc: lsr r2, r2, #16 and r2, r2, #0xff cmp r2, #0 - bne guest_trap @ Guest called HVC + bne guest_hvc_trap @ Guest called HVC /* * Getting here means host called HVC, we shift parameters and branch @@ -149,7 +234,14 @@ hyp_hvc: bx ip 1: - push {lr} + /* + * Pushing r2 here is just a way of keeping the stack aligned to + * 8 bytes on any path that can trigger a HYP exception. Here, + * we may well be about to jump into the guest, and the guest + * exit would otherwise be badly decoded by our fancy + * "decode-exception-without-a-branch" code... + */ + push {r2, lr} mov lr, r0 mov r0, r1 @@ -159,7 +251,21 @@ hyp_hvc: THUMB( orr lr, #1) blx lr @ Call the HYP function - pop {lr} + pop {r2, lr} + eret + +guest_hvc_trap: + movw r2, #:lower16:ARM_SMCCC_ARCH_WORKAROUND_1 + movt r2, #:upper16:ARM_SMCCC_ARCH_WORKAROUND_1 + ldr r0, [sp] @ Guest's r0 + teq r0, r2 + bne guest_trap + add sp, sp, #12 + @ Returns: + @ r0 = 0 + @ r1 = HSR value (perfectly predictable) + @ r2 = ARM_SMCCC_ARCH_WORKAROUND_1 + mov r0, #0 eret guest_trap: diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index 7f14acf67caf..9357ff52c221 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -415,6 +415,7 @@ config CPU_V7 select CPU_CP15_MPU if !MMU select CPU_HAS_ASID if MMU select CPU_PABRT_V7 + select CPU_SPECTRE if MMU select CPU_THUMB_CAPABLE select CPU_TLB_V7 if MMU @@ -826,6 +827,28 @@ config CPU_BPREDICT_DISABLE help Say Y here to disable branch prediction. If unsure, say N. +config CPU_SPECTRE + bool + +config HARDEN_BRANCH_PREDICTOR + bool "Harden the branch predictor against aliasing attacks" if EXPERT + depends on CPU_SPECTRE + default y + help + Speculation attacks against some high-performance processors rely + on being able to manipulate the branch predictor for a victim + context by executing aliasing branches in the attacker context. + Such attacks can be partially mitigated against by clearing + internal branch predictor state and limiting the prediction + logic in some situations. + + This config option will take CPU-specific actions to harden + the branch predictor against aliasing attacks and may rely on + specific instruction sequences or control bits being set by + the system firmware. + + If unsure, say Y. + config TLS_REG_EMUL bool select NEED_KUSER_HELPERS diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 9dbb84923e12..7cb1699fbfc4 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -10,7 +10,7 @@ obj-$(CONFIG_MMU) += fault-armv.o flush.o idmap.o ioremap.o \ ifneq ($(CONFIG_MMU),y) obj-y += nommu.o -obj-$(CONFIG_ARM_MPU) += pmsa-v7.o +obj-$(CONFIG_ARM_MPU) += pmsa-v7.o pmsa-v8.o endif obj-$(CONFIG_ARM_PTDUMP_CORE) += dump.o @@ -97,7 +97,7 @@ obj-$(CONFIG_CPU_MOHAWK) += proc-mohawk.o obj-$(CONFIG_CPU_FEROCEON) += proc-feroceon.o obj-$(CONFIG_CPU_V6) += proc-v6.o obj-$(CONFIG_CPU_V6K) += proc-v6.o -obj-$(CONFIG_CPU_V7) += proc-v7.o +obj-$(CONFIG_CPU_V7) += proc-v7.o proc-v7-bugs.o obj-$(CONFIG_CPU_V7M) += proc-v7m.o AFLAGS_proc-v6.o :=-Wa,-march=armv6 diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 8c398fedbbb6..c25cca69ab46 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -845,7 +845,7 @@ static int __arm_dma_mmap(struct device *dev, struct vm_area_struct *vma, unsigned long attrs) { int ret; - unsigned long nr_vma_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; + unsigned long nr_vma_pages = vma_pages(vma); unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; unsigned long pfn = dma_to_pfn(dev, dma_addr); unsigned long off = vma->vm_pgoff; diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index b75eada23d0a..3b1ba003c4f9 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -163,6 +163,9 @@ __do_user_fault(struct task_struct *tsk, unsigned long addr, { struct siginfo si; + if (addr > TASK_SIZE) + harden_branch_predictor(); + #ifdef CONFIG_DEBUG_USER if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) || ((user_debug & UDBG_BUS) && (sig == SIGBUS))) { diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c index 7c087961b7ce..5dd6c58d653b 100644 --- a/arch/arm/mm/nommu.c +++ b/arch/arm/mm/nommu.c @@ -99,6 +99,38 @@ void __init arm_mm_memblock_reserve(void) memblock_reserve(0, 1); } +static void __init adjust_lowmem_bounds_mpu(void) +{ + unsigned long pmsa = read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA; + + switch (pmsa) { + case MMFR0_PMSAv7: + pmsav7_adjust_lowmem_bounds(); + break; + case MMFR0_PMSAv8: + pmsav8_adjust_lowmem_bounds(); + break; + default: + break; + } +} + +static void __init mpu_setup(void) +{ + unsigned long pmsa = read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA; + + switch (pmsa) { + case MMFR0_PMSAv7: + pmsav7_setup(); + break; + case MMFR0_PMSAv8: + pmsav8_setup(); + break; + default: + break; + } +} + void __init adjust_lowmem_bounds(void) { phys_addr_t end; diff --git a/arch/arm/mm/pmsa-v7.c b/arch/arm/mm/pmsa-v7.c index e2853bfff74e..699fa2e88725 100644 --- a/arch/arm/mm/pmsa-v7.c +++ b/arch/arm/mm/pmsa-v7.c @@ -102,7 +102,7 @@ static inline u32 irbar_read(void) static inline void rgnr_write(u32 v) { - writel_relaxed(v, BASEADDR_V7M_SCB + MPU_RNR); + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv7_RNR); } /* Data-side / unified region attributes */ @@ -110,28 +110,28 @@ static inline void rgnr_write(u32 v) /* Region access control register */ static inline void dracr_write(u32 v) { - u32 rsr = readl_relaxed(BASEADDR_V7M_SCB + MPU_RASR) & GENMASK(15, 0); + u32 rsr = readl_relaxed(BASEADDR_V7M_SCB + PMSAv7_RASR) & GENMASK(15, 0); - writel_relaxed((v << 16) | rsr, BASEADDR_V7M_SCB + MPU_RASR); + writel_relaxed((v << 16) | rsr, BASEADDR_V7M_SCB + PMSAv7_RASR); } /* Region size register */ static inline void drsr_write(u32 v) { - u32 racr = readl_relaxed(BASEADDR_V7M_SCB + MPU_RASR) & GENMASK(31, 16); + u32 racr = readl_relaxed(BASEADDR_V7M_SCB + PMSAv7_RASR) & GENMASK(31, 16); - writel_relaxed(v | racr, BASEADDR_V7M_SCB + MPU_RASR); + writel_relaxed(v | racr, BASEADDR_V7M_SCB + PMSAv7_RASR); } /* Region base address register */ static inline void drbar_write(u32 v) { - writel_relaxed(v, BASEADDR_V7M_SCB + MPU_RBAR); + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv7_RBAR); } static inline u32 drbar_read(void) { - return readl_relaxed(BASEADDR_V7M_SCB + MPU_RBAR); + return readl_relaxed(BASEADDR_V7M_SCB + PMSAv7_RBAR); } /* ARMv7-M only supports a unified MPU, so I-side operations are nop */ @@ -143,11 +143,6 @@ static inline unsigned long irbar_read(void) {return 0;} #endif -static int __init mpu_present(void) -{ - return ((read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA) == MMFR0_PMSAv7); -} - static bool __init try_split_region(phys_addr_t base, phys_addr_t size, struct region *region) { unsigned long subreg, bslots, sslots; @@ -161,7 +156,7 @@ static bool __init try_split_region(phys_addr_t base, phys_addr_t size, struct r bdiff = base - abase; sdiff = p2size - asize; - subreg = p2size / MPU_NR_SUBREGS; + subreg = p2size / PMSAv7_NR_SUBREGS; if ((bdiff % subreg) || (sdiff % subreg)) return false; @@ -172,17 +167,17 @@ static bool __init try_split_region(phys_addr_t base, phys_addr_t size, struct r if (bslots || sslots) { int i; - if (subreg < MPU_MIN_SUBREG_SIZE) + if (subreg < PMSAv7_MIN_SUBREG_SIZE) return false; - if (bslots + sslots > MPU_NR_SUBREGS) + if (bslots + sslots > PMSAv7_NR_SUBREGS) return false; for (i = 0; i < bslots; i++) _set_bit(i, ®ion->subreg); for (i = 1; i <= sslots; i++) - _set_bit(MPU_NR_SUBREGS - i, ®ion->subreg); + _set_bit(PMSAv7_NR_SUBREGS - i, ®ion->subreg); } region->base = abase; @@ -233,7 +228,7 @@ static int __init allocate_region(phys_addr_t base, phys_addr_t size, } /* MPU initialisation functions */ -void __init adjust_lowmem_bounds_mpu(void) +void __init pmsav7_adjust_lowmem_bounds(void) { phys_addr_t specified_mem_size = 0, total_mem_size = 0; struct memblock_region *reg; @@ -243,10 +238,7 @@ void __init adjust_lowmem_bounds_mpu(void) unsigned int mem_max_regions; int num, i; - if (!mpu_present()) - return; - - /* Free-up MPU_PROBE_REGION */ + /* Free-up PMSAv7_PROBE_REGION */ mpu_min_region_order = __mpu_min_region_order(); /* How many regions are supported */ @@ -301,12 +293,12 @@ void __init adjust_lowmem_bounds_mpu(void) num = allocate_region(mem_start, specified_mem_size, mem_max_regions, mem); for (i = 0; i < num; i++) { - unsigned long subreg = mem[i].size / MPU_NR_SUBREGS; + unsigned long subreg = mem[i].size / PMSAv7_NR_SUBREGS; total_mem_size += mem[i].size - subreg * hweight_long(mem[i].subreg); pr_debug("MPU: base %pa size %pa disable subregions: %*pbl\n", - &mem[i].base, &mem[i].size, MPU_NR_SUBREGS, &mem[i].subreg); + &mem[i].base, &mem[i].size, PMSAv7_NR_SUBREGS, &mem[i].subreg); } if (total_mem_size != specified_mem_size) { @@ -349,7 +341,7 @@ static int __init __mpu_min_region_order(void) u32 drbar_result, irbar_result; /* We've kept a region free for this probing */ - rgnr_write(MPU_PROBE_REGION); + rgnr_write(PMSAv7_PROBE_REGION); isb(); /* * As per ARM ARM, write 0xFFFFFFFC to DRBAR to find the minimum @@ -388,8 +380,8 @@ static int __init mpu_setup_region(unsigned int number, phys_addr_t start, return -ENOMEM; /* Writing N to bits 5:1 (RSR_SZ) specifies region size 2^N+1 */ - size_data = ((size_order - 1) << MPU_RSR_SZ) | 1 << MPU_RSR_EN; - size_data |= subregions << MPU_RSR_SD; + size_data = ((size_order - 1) << PMSAv7_RSR_SZ) | 1 << PMSAv7_RSR_EN; + size_data |= subregions << PMSAv7_RSR_SD; if (need_flush) flush_cache_all(); @@ -424,18 +416,15 @@ static int __init mpu_setup_region(unsigned int number, phys_addr_t start, /* * Set up default MPU regions, doing nothing if there is no MPU */ -void __init mpu_setup(void) +void __init pmsav7_setup(void) { int i, region = 0, err = 0; - if (!mpu_present()) - return; - /* Setup MPU (order is important) */ /* Background */ err |= mpu_setup_region(region++, 0, 32, - MPU_ACR_XN | MPU_RGN_STRONGLY_ORDERED | MPU_AP_PL1RW_PL0RW, + PMSAv7_ACR_XN | PMSAv7_RGN_STRONGLY_ORDERED | PMSAv7_AP_PL1RW_PL0RW, 0, false); #ifdef CONFIG_XIP_KERNEL @@ -448,13 +437,13 @@ void __init mpu_setup(void) * with BG region (which is uncachable), thus we need * to clean and invalidate cache. */ - bool need_flush = region == MPU_RAM_REGION; + bool need_flush = region == PMSAv7_RAM_REGION; if (!xip[i].size) continue; err |= mpu_setup_region(region++, xip[i].base, ilog2(xip[i].size), - MPU_AP_PL1RO_PL0NA | MPU_RGN_NORMAL, + PMSAv7_AP_PL1RO_PL0NA | PMSAv7_RGN_NORMAL, xip[i].subreg, need_flush); } #endif @@ -465,14 +454,14 @@ void __init mpu_setup(void) continue; err |= mpu_setup_region(region++, mem[i].base, ilog2(mem[i].size), - MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL, + PMSAv7_AP_PL1RW_PL0RW | PMSAv7_RGN_NORMAL, mem[i].subreg, false); } /* Vectors */ #ifndef CONFIG_CPU_V7M err |= mpu_setup_region(region++, vectors_base, ilog2(2 * PAGE_SIZE), - MPU_AP_PL1RW_PL0NA | MPU_RGN_NORMAL, + PMSAv7_AP_PL1RW_PL0NA | PMSAv7_RGN_NORMAL, 0, false); #endif if (err) { diff --git a/arch/arm/mm/pmsa-v8.c b/arch/arm/mm/pmsa-v8.c new file mode 100644 index 000000000000..617a83def88a --- /dev/null +++ b/arch/arm/mm/pmsa-v8.c @@ -0,0 +1,307 @@ +/* + * Based on linux/arch/arm/pmsa-v7.c + * + * ARM PMSAv8 supporting functions. + */ + +#include +#include + +#include +#include +#include + +#include +#include + +#include "mm.h" + +#ifndef CONFIG_CPU_V7M + +#define PRSEL __ACCESS_CP15(c6, 0, c2, 1) +#define PRBAR __ACCESS_CP15(c6, 0, c3, 0) +#define PRLAR __ACCESS_CP15(c6, 0, c3, 1) + +static inline u32 prlar_read(void) +{ + return read_sysreg(PRLAR); +} + +static inline u32 prbar_read(void) +{ + return read_sysreg(PRBAR); +} + +static inline void prsel_write(u32 v) +{ + write_sysreg(v, PRSEL); +} + +static inline void prbar_write(u32 v) +{ + write_sysreg(v, PRBAR); +} + +static inline void prlar_write(u32 v) +{ + write_sysreg(v, PRLAR); +} +#else + +static inline u32 prlar_read(void) +{ + return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RLAR); +} + +static inline u32 prbar_read(void) +{ + return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RBAR); +} + +static inline void prsel_write(u32 v) +{ + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RNR); +} + +static inline void prbar_write(u32 v) +{ + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RBAR); +} + +static inline void prlar_write(u32 v) +{ + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RLAR); +} + +#endif + +static struct range __initdata io[MPU_MAX_REGIONS]; +static struct range __initdata mem[MPU_MAX_REGIONS]; + +static unsigned int __initdata mpu_max_regions; + +static __init bool is_region_fixed(int number) +{ + switch (number) { + case PMSAv8_XIP_REGION: + case PMSAv8_KERNEL_REGION: + return true; + default: + return false; + } +} + +void __init pmsav8_adjust_lowmem_bounds(void) +{ + phys_addr_t mem_end; + struct memblock_region *reg; + bool first = true; + + for_each_memblock(memory, reg) { + if (first) { + phys_addr_t phys_offset = PHYS_OFFSET; + + /* + * Initially only use memory continuous from + * PHYS_OFFSET */ + if (reg->base != phys_offset) + panic("First memory bank must be contiguous from PHYS_OFFSET"); + mem_end = reg->base + reg->size; + first = false; + } else { + /* + * memblock auto merges contiguous blocks, remove + * all blocks afterwards in one go (we can't remove + * blocks separately while iterating) + */ + pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n", + &mem_end, ®->base); + memblock_remove(reg->base, 0 - reg->base); + break; + } + } +} + +static int __init __mpu_max_regions(void) +{ + static int max_regions; + u32 mpuir; + + if (max_regions) + return max_regions; + + mpuir = read_cpuid_mputype(); + + max_regions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION; + + return max_regions; +} + +static int __init __pmsav8_setup_region(unsigned int number, u32 bar, u32 lar) +{ + if (number > mpu_max_regions + || number >= MPU_MAX_REGIONS) + return -ENOENT; + + dsb(); + prsel_write(number); + isb(); + prbar_write(bar); + prlar_write(lar); + + mpu_rgn_info.rgns[number].prbar = bar; + mpu_rgn_info.rgns[number].prlar = lar; + + mpu_rgn_info.used++; + + return 0; +} + +static int __init pmsav8_setup_ram(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (is_region_fixed(number)) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);; + + bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN; + + return __pmsav8_setup_region(number, bar, lar); +} + +static int __init pmsav8_setup_io(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (is_region_fixed(number)) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);; + + bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN; + + return __pmsav8_setup_region(number, bar, lar); +} + +static int __init pmsav8_setup_fixed(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (!is_region_fixed(number)) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1); + + bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN; + + prsel_write(number); + isb(); + + if (prbar_read() != bar || prlar_read() != lar) + return -EINVAL; + + /* Reserved region was set up early, we just need a record for secondaries */ + mpu_rgn_info.rgns[number].prbar = bar; + mpu_rgn_info.rgns[number].prlar = lar; + + mpu_rgn_info.used++; + + return 0; +} + +#ifndef CONFIG_CPU_V7M +static int __init pmsav8_setup_vector(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (number == PMSAv8_KERNEL_REGION) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1); + + bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN; + + return __pmsav8_setup_region(number, bar, lar); +} +#endif + +void __init pmsav8_setup(void) +{ + int i, err = 0; + int region = PMSAv8_KERNEL_REGION; + + /* How many regions are supported ? */ + mpu_max_regions = __mpu_max_regions(); + + /* RAM: single chunk of memory */ + add_range(mem, ARRAY_SIZE(mem), 0, memblock.memory.regions[0].base, + memblock.memory.regions[0].base + memblock.memory.regions[0].size); + + /* IO: cover full 4G range */ + add_range(io, ARRAY_SIZE(io), 0, 0, 0xffffffff); + + /* RAM and IO: exclude kernel */ + subtract_range(mem, ARRAY_SIZE(mem), __pa(KERNEL_START), __pa(KERNEL_END)); + subtract_range(io, ARRAY_SIZE(io), __pa(KERNEL_START), __pa(KERNEL_END)); + +#ifdef CONFIG_XIP_KERNEL + /* RAM and IO: exclude xip */ + subtract_range(mem, ARRAY_SIZE(mem), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom)); + subtract_range(io, ARRAY_SIZE(io), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom)); +#endif + +#ifndef CONFIG_CPU_V7M + /* RAM and IO: exclude vectors */ + subtract_range(mem, ARRAY_SIZE(mem), vectors_base, vectors_base + 2 * PAGE_SIZE); + subtract_range(io, ARRAY_SIZE(io), vectors_base, vectors_base + 2 * PAGE_SIZE); +#endif + /* IO: exclude RAM */ + for (i = 0; i < ARRAY_SIZE(mem); i++) + subtract_range(io, ARRAY_SIZE(io), mem[i].start, mem[i].end); + + /* Now program MPU */ + +#ifdef CONFIG_XIP_KERNEL + /* ROM */ + err |= pmsav8_setup_fixed(PMSAv8_XIP_REGION, CONFIG_XIP_PHYS_ADDR, __pa(_exiprom)); +#endif + /* Kernel */ + err |= pmsav8_setup_fixed(region++, __pa(KERNEL_START), __pa(KERNEL_END)); + + + /* IO */ + for (i = 0; i < ARRAY_SIZE(io); i++) { + if (!io[i].end) + continue; + + err |= pmsav8_setup_io(region++, io[i].start, io[i].end); + } + + /* RAM */ + for (i = 0; i < ARRAY_SIZE(mem); i++) { + if (!mem[i].end) + continue; + + err |= pmsav8_setup_ram(region++, mem[i].start, mem[i].end); + } + + /* Vectors */ +#ifndef CONFIG_CPU_V7M + err |= pmsav8_setup_vector(region++, vectors_base, vectors_base + 2 * PAGE_SIZE); +#endif + if (err) + pr_warn("MPU region initialization failure! %d", err); + else + pr_info("Using ARM PMSAv8 Compliant MPU. Used %d of %d regions\n", + mpu_rgn_info.used, mpu_max_regions); +} diff --git a/arch/arm/mm/proc-macros.S b/arch/arm/mm/proc-macros.S index f10e31d0730a..81d0efb055c6 100644 --- a/arch/arm/mm/proc-macros.S +++ b/arch/arm/mm/proc-macros.S @@ -273,13 +273,14 @@ mcr p15, 0, ip, c7, c10, 4 @ data write barrier .endm -.macro define_processor_functions name:req, dabort:req, pabort:req, nommu=0, suspend=0 +.macro define_processor_functions name:req, dabort:req, pabort:req, nommu=0, suspend=0, bugs=0 .type \name\()_processor_functions, #object .align 2 ENTRY(\name\()_processor_functions) .word \dabort .word \pabort .word cpu_\name\()_proc_init + .word \bugs .word cpu_\name\()_proc_fin .word cpu_\name\()_reset .word cpu_\name\()_do_idle diff --git a/arch/arm/mm/proc-v7-2level.S b/arch/arm/mm/proc-v7-2level.S index c6141a5435c3..f8d45ad2a515 100644 --- a/arch/arm/mm/proc-v7-2level.S +++ b/arch/arm/mm/proc-v7-2level.S @@ -41,11 +41,6 @@ * even on Cortex-A8 revisions not affected by 430973. * If IBE is not set, the flush BTAC/BTB won't do anything. */ -ENTRY(cpu_ca8_switch_mm) -#ifdef CONFIG_MMU - mov r2, #0 - mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB -#endif ENTRY(cpu_v7_switch_mm) #ifdef CONFIG_MMU mmid r1, r1 @ get mm->context.id @@ -66,7 +61,6 @@ ENTRY(cpu_v7_switch_mm) #endif bx lr ENDPROC(cpu_v7_switch_mm) -ENDPROC(cpu_ca8_switch_mm) /* * cpu_v7_set_pte_ext(ptep, pte) diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c new file mode 100644 index 000000000000..5544b82a2e7a --- /dev/null +++ b/arch/arm/mm/proc-v7-bugs.c @@ -0,0 +1,174 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include + +#include +#include +#include +#include + +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR +DEFINE_PER_CPU(harden_branch_predictor_fn_t, harden_branch_predictor_fn); + +extern void cpu_v7_iciallu_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm); +extern void cpu_v7_bpiall_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm); +extern void cpu_v7_smc_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm); +extern void cpu_v7_hvc_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm); + +static void harden_branch_predictor_bpiall(void) +{ + write_sysreg(0, BPIALL); +} + +static void harden_branch_predictor_iciallu(void) +{ + write_sysreg(0, ICIALLU); +} + +static void __maybe_unused call_smc_arch_workaround_1(void) +{ + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); +} + +static void __maybe_unused call_hvc_arch_workaround_1(void) +{ + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); +} + +static void cpu_v7_spectre_init(void) +{ + const char *spectre_v2_method = NULL; + int cpu = smp_processor_id(); + + if (per_cpu(harden_branch_predictor_fn, cpu)) + return; + + switch (read_cpuid_part()) { + case ARM_CPU_PART_CORTEX_A8: + case ARM_CPU_PART_CORTEX_A9: + case ARM_CPU_PART_CORTEX_A12: + case ARM_CPU_PART_CORTEX_A17: + case ARM_CPU_PART_CORTEX_A73: + case ARM_CPU_PART_CORTEX_A75: + if (processor.switch_mm != cpu_v7_bpiall_switch_mm) + goto bl_error; + per_cpu(harden_branch_predictor_fn, cpu) = + harden_branch_predictor_bpiall; + spectre_v2_method = "BPIALL"; + break; + + case ARM_CPU_PART_CORTEX_A15: + case ARM_CPU_PART_BRAHMA_B15: + if (processor.switch_mm != cpu_v7_iciallu_switch_mm) + goto bl_error; + per_cpu(harden_branch_predictor_fn, cpu) = + harden_branch_predictor_iciallu; + spectre_v2_method = "ICIALLU"; + break; + +#ifdef CONFIG_ARM_PSCI + default: + /* Other ARM CPUs require no workaround */ + if (read_cpuid_implementor() == ARM_CPU_IMP_ARM) + break; + /* fallthrough */ + /* Cortex A57/A72 require firmware workaround */ + case ARM_CPU_PART_CORTEX_A57: + case ARM_CPU_PART_CORTEX_A72: { + struct arm_smccc_res res; + + if (psci_ops.smccc_version == SMCCC_VERSION_1_0) + break; + + switch (psci_ops.conduit) { + case PSCI_CONDUIT_HVC: + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_1, &res); + if ((int)res.a0 != 0) + break; + if (processor.switch_mm != cpu_v7_hvc_switch_mm && cpu) + goto bl_error; + per_cpu(harden_branch_predictor_fn, cpu) = + call_hvc_arch_workaround_1; + processor.switch_mm = cpu_v7_hvc_switch_mm; + spectre_v2_method = "hypervisor"; + break; + + case PSCI_CONDUIT_SMC: + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_1, &res); + if ((int)res.a0 != 0) + break; + if (processor.switch_mm != cpu_v7_smc_switch_mm && cpu) + goto bl_error; + per_cpu(harden_branch_predictor_fn, cpu) = + call_smc_arch_workaround_1; + processor.switch_mm = cpu_v7_smc_switch_mm; + spectre_v2_method = "firmware"; + break; + + default: + break; + } + } +#endif + } + + if (spectre_v2_method) + pr_info("CPU%u: Spectre v2: using %s workaround\n", + smp_processor_id(), spectre_v2_method); + return; + +bl_error: + pr_err("CPU%u: Spectre v2: incorrect context switching function, system vulnerable\n", + cpu); +} +#else +static void cpu_v7_spectre_init(void) +{ +} +#endif + +static __maybe_unused bool cpu_v7_check_auxcr_set(bool *warned, + u32 mask, const char *msg) +{ + u32 aux_cr; + + asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (aux_cr)); + + if ((aux_cr & mask) != mask) { + if (!*warned) + pr_err("CPU%u: %s", smp_processor_id(), msg); + *warned = true; + return false; + } + return true; +} + +static DEFINE_PER_CPU(bool, spectre_warned); + +static bool check_spectre_auxcr(bool *warned, u32 bit) +{ + return IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR) && + cpu_v7_check_auxcr_set(warned, bit, + "Spectre v2: firmware did not set auxiliary control register IBE bit, system vulnerable\n"); +} + +void cpu_v7_ca8_ibe(void) +{ + if (check_spectre_auxcr(this_cpu_ptr(&spectre_warned), BIT(6))) + cpu_v7_spectre_init(); +} + +void cpu_v7_ca15_ibe(void) +{ + if (check_spectre_auxcr(this_cpu_ptr(&spectre_warned), BIT(0))) + cpu_v7_spectre_init(); +} + +void cpu_v7_bugs_init(void) +{ + cpu_v7_spectre_init(); +} diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index b528a15f460d..6fe52819e014 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -9,6 +9,7 @@ * * This is the "shell" of the ARMv7 processor support. */ +#include #include #include #include @@ -93,6 +94,37 @@ ENTRY(cpu_v7_dcache_clean_area) ret lr ENDPROC(cpu_v7_dcache_clean_area) +#ifdef CONFIG_ARM_PSCI + .arch_extension sec +ENTRY(cpu_v7_smc_switch_mm) + stmfd sp!, {r0 - r3} + movw r0, #:lower16:ARM_SMCCC_ARCH_WORKAROUND_1 + movt r0, #:upper16:ARM_SMCCC_ARCH_WORKAROUND_1 + smc #0 + ldmfd sp!, {r0 - r3} + b cpu_v7_switch_mm +ENDPROC(cpu_v7_smc_switch_mm) + .arch_extension virt +ENTRY(cpu_v7_hvc_switch_mm) + stmfd sp!, {r0 - r3} + movw r0, #:lower16:ARM_SMCCC_ARCH_WORKAROUND_1 + movt r0, #:upper16:ARM_SMCCC_ARCH_WORKAROUND_1 + hvc #0 + ldmfd sp!, {r0 - r3} + b cpu_v7_switch_mm +ENDPROC(cpu_v7_smc_switch_mm) +#endif +ENTRY(cpu_v7_iciallu_switch_mm) + mov r3, #0 + mcr p15, 0, r3, c7, c5, 0 @ ICIALLU + b cpu_v7_switch_mm +ENDPROC(cpu_v7_iciallu_switch_mm) +ENTRY(cpu_v7_bpiall_switch_mm) + mov r3, #0 + mcr p15, 0, r3, c7, c5, 6 @ flush BTAC/BTB + b cpu_v7_switch_mm +ENDPROC(cpu_v7_bpiall_switch_mm) + string cpu_v7_name, "ARMv7 Processor" .align @@ -158,31 +190,6 @@ ENTRY(cpu_v7_do_resume) ENDPROC(cpu_v7_do_resume) #endif -/* - * Cortex-A8 - */ - globl_equ cpu_ca8_proc_init, cpu_v7_proc_init - globl_equ cpu_ca8_proc_fin, cpu_v7_proc_fin - globl_equ cpu_ca8_reset, cpu_v7_reset - globl_equ cpu_ca8_do_idle, cpu_v7_do_idle - globl_equ cpu_ca8_dcache_clean_area, cpu_v7_dcache_clean_area - globl_equ cpu_ca8_set_pte_ext, cpu_v7_set_pte_ext - globl_equ cpu_ca8_suspend_size, cpu_v7_suspend_size -#ifdef CONFIG_ARM_CPU_SUSPEND - globl_equ cpu_ca8_do_suspend, cpu_v7_do_suspend - globl_equ cpu_ca8_do_resume, cpu_v7_do_resume -#endif - -/* - * Cortex-A9 processor functions - */ - globl_equ cpu_ca9mp_proc_init, cpu_v7_proc_init - globl_equ cpu_ca9mp_proc_fin, cpu_v7_proc_fin - globl_equ cpu_ca9mp_reset, cpu_v7_reset - globl_equ cpu_ca9mp_do_idle, cpu_v7_do_idle - globl_equ cpu_ca9mp_dcache_clean_area, cpu_v7_dcache_clean_area - globl_equ cpu_ca9mp_switch_mm, cpu_v7_switch_mm - globl_equ cpu_ca9mp_set_pte_ext, cpu_v7_set_pte_ext .globl cpu_ca9mp_suspend_size .equ cpu_ca9mp_suspend_size, cpu_v7_suspend_size + 4 * 2 #ifdef CONFIG_ARM_CPU_SUSPEND @@ -547,12 +554,79 @@ __v7_setup_stack: __INITDATA + .weak cpu_v7_bugs_init + @ define struct processor (see and proc-macros.S) - define_processor_functions v7, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 -#ifndef CONFIG_ARM_LPAE - define_processor_functions ca8, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 - define_processor_functions ca9mp, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 + define_processor_functions v7, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_bugs_init + +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + @ generic v7 bpiall on context switch + globl_equ cpu_v7_bpiall_proc_init, cpu_v7_proc_init + globl_equ cpu_v7_bpiall_proc_fin, cpu_v7_proc_fin + globl_equ cpu_v7_bpiall_reset, cpu_v7_reset + globl_equ cpu_v7_bpiall_do_idle, cpu_v7_do_idle + globl_equ cpu_v7_bpiall_dcache_clean_area, cpu_v7_dcache_clean_area + globl_equ cpu_v7_bpiall_set_pte_ext, cpu_v7_set_pte_ext + globl_equ cpu_v7_bpiall_suspend_size, cpu_v7_suspend_size +#ifdef CONFIG_ARM_CPU_SUSPEND + globl_equ cpu_v7_bpiall_do_suspend, cpu_v7_do_suspend + globl_equ cpu_v7_bpiall_do_resume, cpu_v7_do_resume #endif + define_processor_functions v7_bpiall, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_bugs_init + +#define HARDENED_BPIALL_PROCESSOR_FUNCTIONS v7_bpiall_processor_functions +#else +#define HARDENED_BPIALL_PROCESSOR_FUNCTIONS v7_processor_functions +#endif + +#ifndef CONFIG_ARM_LPAE + @ Cortex-A8 - always needs bpiall switch_mm implementation + globl_equ cpu_ca8_proc_init, cpu_v7_proc_init + globl_equ cpu_ca8_proc_fin, cpu_v7_proc_fin + globl_equ cpu_ca8_reset, cpu_v7_reset + globl_equ cpu_ca8_do_idle, cpu_v7_do_idle + globl_equ cpu_ca8_dcache_clean_area, cpu_v7_dcache_clean_area + globl_equ cpu_ca8_set_pte_ext, cpu_v7_set_pte_ext + globl_equ cpu_ca8_switch_mm, cpu_v7_bpiall_switch_mm + globl_equ cpu_ca8_suspend_size, cpu_v7_suspend_size +#ifdef CONFIG_ARM_CPU_SUSPEND + globl_equ cpu_ca8_do_suspend, cpu_v7_do_suspend + globl_equ cpu_ca8_do_resume, cpu_v7_do_resume +#endif + define_processor_functions ca8, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_ca8_ibe + + @ Cortex-A9 - needs more registers preserved across suspend/resume + @ and bpiall switch_mm for hardening + globl_equ cpu_ca9mp_proc_init, cpu_v7_proc_init + globl_equ cpu_ca9mp_proc_fin, cpu_v7_proc_fin + globl_equ cpu_ca9mp_reset, cpu_v7_reset + globl_equ cpu_ca9mp_do_idle, cpu_v7_do_idle + globl_equ cpu_ca9mp_dcache_clean_area, cpu_v7_dcache_clean_area +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + globl_equ cpu_ca9mp_switch_mm, cpu_v7_bpiall_switch_mm +#else + globl_equ cpu_ca9mp_switch_mm, cpu_v7_switch_mm +#endif + globl_equ cpu_ca9mp_set_pte_ext, cpu_v7_set_pte_ext + define_processor_functions ca9mp, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_bugs_init +#endif + + @ Cortex-A15 - needs iciallu switch_mm for hardening + globl_equ cpu_ca15_proc_init, cpu_v7_proc_init + globl_equ cpu_ca15_proc_fin, cpu_v7_proc_fin + globl_equ cpu_ca15_reset, cpu_v7_reset + globl_equ cpu_ca15_do_idle, cpu_v7_do_idle + globl_equ cpu_ca15_dcache_clean_area, cpu_v7_dcache_clean_area +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + globl_equ cpu_ca15_switch_mm, cpu_v7_iciallu_switch_mm +#else + globl_equ cpu_ca15_switch_mm, cpu_v7_switch_mm +#endif + globl_equ cpu_ca15_set_pte_ext, cpu_v7_set_pte_ext + globl_equ cpu_ca15_suspend_size, cpu_v7_suspend_size + globl_equ cpu_ca15_do_suspend, cpu_v7_do_suspend + globl_equ cpu_ca15_do_resume, cpu_v7_do_resume + define_processor_functions ca15, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_ca15_ibe #ifdef CONFIG_CPU_PJ4B define_processor_functions pj4b, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 #endif @@ -669,7 +743,7 @@ __v7_ca7mp_proc_info: __v7_ca12mp_proc_info: .long 0x410fc0d0 .long 0xff0ffff0 - __v7_proc __v7_ca12mp_proc_info, __v7_ca12mp_setup + __v7_proc __v7_ca12mp_proc_info, __v7_ca12mp_setup, proc_fns = HARDENED_BPIALL_PROCESSOR_FUNCTIONS .size __v7_ca12mp_proc_info, . - __v7_ca12mp_proc_info /* @@ -679,7 +753,7 @@ __v7_ca12mp_proc_info: __v7_ca15mp_proc_info: .long 0x410fc0f0 .long 0xff0ffff0 - __v7_proc __v7_ca15mp_proc_info, __v7_ca15mp_setup + __v7_proc __v7_ca15mp_proc_info, __v7_ca15mp_setup, proc_fns = ca15_processor_functions .size __v7_ca15mp_proc_info, . - __v7_ca15mp_proc_info /* @@ -689,7 +763,7 @@ __v7_ca15mp_proc_info: __v7_b15mp_proc_info: .long 0x420f00f0 .long 0xff0ffff0 - __v7_proc __v7_b15mp_proc_info, __v7_b15mp_setup, cache_fns = b15_cache_fns + __v7_proc __v7_b15mp_proc_info, __v7_b15mp_setup, proc_fns = ca15_processor_functions, cache_fns = b15_cache_fns .size __v7_b15mp_proc_info, . - __v7_b15mp_proc_info /* @@ -699,9 +773,25 @@ __v7_b15mp_proc_info: __v7_ca17mp_proc_info: .long 0x410fc0e0 .long 0xff0ffff0 - __v7_proc __v7_ca17mp_proc_info, __v7_ca17mp_setup + __v7_proc __v7_ca17mp_proc_info, __v7_ca17mp_setup, proc_fns = HARDENED_BPIALL_PROCESSOR_FUNCTIONS .size __v7_ca17mp_proc_info, . - __v7_ca17mp_proc_info + /* ARM Ltd. Cortex A73 processor */ + .type __v7_ca73_proc_info, #object +__v7_ca73_proc_info: + .long 0x410fd090 + .long 0xff0ffff0 + __v7_proc __v7_ca73_proc_info, __v7_setup, proc_fns = HARDENED_BPIALL_PROCESSOR_FUNCTIONS + .size __v7_ca73_proc_info, . - __v7_ca73_proc_info + + /* ARM Ltd. Cortex A75 processor */ + .type __v7_ca75_proc_info, #object +__v7_ca75_proc_info: + .long 0x410fd0a0 + .long 0xff0ffff0 + __v7_proc __v7_ca75_proc_info, __v7_setup, proc_fns = HARDENED_BPIALL_PROCESSOR_FUNCTIONS + .size __v7_ca75_proc_info, . - __v7_ca75_proc_info + /* * Qualcomm Inc. Krait processors. */ diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 594c228d2f02..12283bd06733 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -197,6 +197,7 @@ struct bus_type amba_bustype = { .pm = &amba_pm, .force_dma = true, }; +EXPORT_SYMBOL_GPL(amba_bustype); static int __init amba_init(void) {