diff options
Diffstat (limited to 'arch/arm64/kernel/insn.c')
-rw-r--r-- | arch/arm64/kernel/insn.c | 149 |
1 files changed, 3 insertions, 146 deletions
diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index 6c0de2f60ea9..952e7d6fe60e 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -7,21 +7,14 @@ */ #include <linux/bitops.h> #include <linux/bug.h> -#include <linux/compiler.h> -#include <linux/kernel.h> -#include <linux/mm.h> -#include <linux/smp.h> -#include <linux/spinlock.h> -#include <linux/stop_machine.h> +#include <linux/printk.h> +#include <linux/sizes.h> #include <linux/types.h> -#include <linux/uaccess.h> -#include <asm/cacheflush.h> #include <asm/debug-monitors.h> -#include <asm/fixmap.h> +#include <asm/errno.h> #include <asm/insn.h> #include <asm/kprobes.h> -#include <asm/sections.h> #define AARCH64_INSN_SF_BIT BIT(31) #define AARCH64_INSN_N_BIT BIT(22) @@ -83,81 +76,6 @@ bool aarch64_insn_is_branch_imm(u32 insn) aarch64_insn_is_bcond(insn)); } -static DEFINE_RAW_SPINLOCK(patch_lock); - -static bool is_exit_text(unsigned long addr) -{ - /* discarded with init text/data */ - return system_state < SYSTEM_RUNNING && - addr >= (unsigned long)__exittext_begin && - addr < (unsigned long)__exittext_end; -} - -static bool is_image_text(unsigned long addr) -{ - return core_kernel_text(addr) || is_exit_text(addr); -} - -static void __kprobes *patch_map(void *addr, int fixmap) -{ - unsigned long uintaddr = (uintptr_t) addr; - bool image = is_image_text(uintaddr); - struct page *page; - - if (image) - page = phys_to_page(__pa_symbol(addr)); - else if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) - page = vmalloc_to_page(addr); - else - return addr; - - BUG_ON(!page); - return (void *)set_fixmap_offset(fixmap, page_to_phys(page) + - (uintaddr & ~PAGE_MASK)); -} - -static void __kprobes patch_unmap(int fixmap) -{ - clear_fixmap(fixmap); -} -/* - * In ARMv8-A, A64 instructions have a fixed length of 32 bits and are always - * little-endian. - */ -int __kprobes aarch64_insn_read(void *addr, u32 *insnp) -{ - int ret; - __le32 val; - - ret = copy_from_kernel_nofault(&val, addr, AARCH64_INSN_SIZE); - if (!ret) - *insnp = le32_to_cpu(val); - - return ret; -} - -static int __kprobes __aarch64_insn_write(void *addr, __le32 insn) -{ - void *waddr = addr; - unsigned long flags = 0; - int ret; - - raw_spin_lock_irqsave(&patch_lock, flags); - waddr = patch_map(addr, FIX_TEXT_POKE0); - - ret = copy_to_kernel_nofault(waddr, &insn, AARCH64_INSN_SIZE); - - patch_unmap(FIX_TEXT_POKE0); - raw_spin_unlock_irqrestore(&patch_lock, flags); - - return ret; -} - -int __kprobes aarch64_insn_write(void *addr, u32 insn) -{ - return __aarch64_insn_write(addr, cpu_to_le32(insn)); -} - bool __kprobes aarch64_insn_uses_literal(u32 insn) { /* ldr/ldrsw (literal), prfm */ @@ -187,67 +105,6 @@ bool __kprobes aarch64_insn_is_branch(u32 insn) aarch64_insn_is_bcond(insn); } -int __kprobes aarch64_insn_patch_text_nosync(void *addr, u32 insn) -{ - u32 *tp = addr; - int ret; - - /* A64 instructions must be word aligned */ - if ((uintptr_t)tp & 0x3) - return -EINVAL; - - ret = aarch64_insn_write(tp, insn); - if (ret == 0) - __flush_icache_range((uintptr_t)tp, - (uintptr_t)tp + AARCH64_INSN_SIZE); - - return ret; -} - -struct aarch64_insn_patch { - void **text_addrs; - u32 *new_insns; - int insn_cnt; - atomic_t cpu_count; -}; - -static int __kprobes aarch64_insn_patch_text_cb(void *arg) -{ - int i, ret = 0; - struct aarch64_insn_patch *pp = arg; - - /* The first CPU becomes master */ - if (atomic_inc_return(&pp->cpu_count) == 1) { - for (i = 0; ret == 0 && i < pp->insn_cnt; i++) - ret = aarch64_insn_patch_text_nosync(pp->text_addrs[i], - pp->new_insns[i]); - /* Notify other processors with an additional increment. */ - atomic_inc(&pp->cpu_count); - } else { - while (atomic_read(&pp->cpu_count) <= num_online_cpus()) - cpu_relax(); - isb(); - } - - return ret; -} - -int __kprobes aarch64_insn_patch_text(void *addrs[], u32 insns[], int cnt) -{ - struct aarch64_insn_patch patch = { - .text_addrs = addrs, - .new_insns = insns, - .insn_cnt = cnt, - .cpu_count = ATOMIC_INIT(0), - }; - - if (cnt <= 0) - return -EINVAL; - - return stop_machine_cpuslocked(aarch64_insn_patch_text_cb, &patch, - cpu_online_mask); -} - static int __kprobes aarch64_get_imm_shift_mask(enum aarch64_insn_imm_type type, u32 *maskp, int *shiftp) { |