/* * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.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 */ #include <linux/ptrace.h> #include <linux/module.h> #include <linux/mm.h> #include <linux/fs.h> #include <linux/kdev_t.h> #include <linux/fs_struct.h> #include <linux/proc_fs.h> #include <linux/file.h> #include <asm/arcregs.h> /* * Common routine to print scratch regs (r0-r12) or callee regs (r13-r25) * -Prints 3 regs per line and a CR. * -To continue, callee regs right after scratch, special handling of CR */ static noinline void print_reg_file(long *reg_rev, int start_num) { unsigned int i; char buf[512]; int n = 0, len = sizeof(buf); for (i = start_num; i < start_num + 13; i++) { n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t", i, (unsigned long)*reg_rev); if (((i + 1) % 3) == 0) n += scnprintf(buf + n, len - n, "\n"); /* because pt_regs has regs reversed: r12..r0, r25..r13 */ reg_rev--; } if (start_num != 0) n += scnprintf(buf + n, len - n, "\n\n"); /* To continue printing callee regs on same line as scratch regs */ if (start_num == 0) pr_info("%s", buf); else pr_cont("%s\n", buf); } static void show_callee_regs(struct callee_regs *cregs) { print_reg_file(&(cregs->r13), 13); } void print_task_path_n_nm(struct task_struct *tsk, char *buf) { struct path path; char *path_nm = NULL; struct mm_struct *mm; struct file *exe_file; mm = get_task_mm(tsk); if (!mm) goto done; exe_file = get_mm_exe_file(mm); mmput(mm); if (exe_file) { path = exe_file->f_path; path_get(&exe_file->f_path); fput(exe_file); path_nm = d_path(&path, buf, 255); path_put(&path); } done: pr_info("Path: %s\n", path_nm); } EXPORT_SYMBOL(print_task_path_n_nm); static void show_faulting_vma(unsigned long address, char *buf) { struct vm_area_struct *vma; struct inode *inode; unsigned long ino = 0; dev_t dev = 0; char *nm = buf; struct mm_struct *active_mm = current->active_mm; /* can't use print_vma_addr() yet as it doesn't check for * non-inclusive vma */ down_read(&active_mm->mmap_sem); vma = find_vma(active_mm, address); /* check against the find_vma( ) behaviour which returns the next VMA * if the container VMA is not found */ if (vma && (vma->vm_start <= address)) { struct file *file = vma->vm_file; if (file) { struct path *path = &file->f_path; nm = d_path(path, buf, PAGE_SIZE - 1); inode = file_inode(vma->vm_file); dev = inode->i_sb->s_dev; ino = inode->i_ino; } pr_info(" @off 0x%lx in [%s]\n" " VMA: 0x%08lx to 0x%08lx\n", vma->vm_start < TASK_UNMAPPED_BASE ? address : address - vma->vm_start, nm, vma->vm_start, vma->vm_end); } else pr_info(" @No matching VMA found\n"); up_read(&active_mm->mmap_sem); } static void show_ecr_verbose(struct pt_regs *regs) { unsigned int vec, cause_code; unsigned long address; pr_info("\n[ECR ]: 0x%08lx => ", regs->event); /* For Data fault, this is data address not instruction addr */ address = current->thread.fault_address; vec = regs->ecr_vec; cause_code = regs->ecr_cause; /* For DTLB Miss or ProtV, display the memory involved too */ if (vec == ECR_V_DTLB_MISS) { pr_cont("Invalid %s @ 0x%08lx by insn @ 0x%08lx\n", (cause_code == 0x01) ? "Read" : ((cause_code == 0x02) ? "Write" : "EX"), address, regs->ret); } else if (vec == ECR_V_ITLB_MISS) { pr_cont("Insn could not be fetched\n"); } else if (vec == ECR_V_MACH_CHK) { pr_cont("%s\n", (cause_code == 0x0) ? "Double Fault" : "Other Fatal Err"); } else if (vec == ECR_V_PROTV) { if (cause_code == ECR_C_PROTV_INST_FETCH) pr_cont("Execute from Non-exec Page\n"); else if (cause_code == ECR_C_PROTV_MISALIG_DATA) pr_cont("Misaligned r/w from 0x%08lx\n", address); else pr_cont("%s access not allowed on page\n", (cause_code == 0x01) ? "Read" : ((cause_code == 0x02) ? "Write" : "EX")); } else if (vec == ECR_V_INSN_ERR) { pr_cont("Illegal Insn\n"); } else { pr_cont("Check Programmer's Manual\n"); } } /************************************************************************ * API called by rest of kernel ***********************************************************************/ void show_regs(struct pt_regs *regs) { struct task_struct *tsk = current; struct callee_regs *cregs; char *buf; buf = (char *)__get_free_page(GFP_TEMPORARY); if (!buf) return; print_task_path_n_nm(tsk, buf); show_regs_print_info(KERN_INFO); show_ecr_verbose(regs); pr_info("[EFA ]: 0x%08lx\n[BLINK ]: %pS\n[ERET ]: %pS\n", current->thread.fault_address, (void *)regs->blink, (void *)regs->ret); if (user_mode(regs)) show_faulting_vma(regs->ret, buf); /* faulting code, not data */ pr_info("[STAT32]: 0x%08lx", regs->status32); #define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit : "" if (!user_mode(regs)) pr_cont(" : %2s %2s %2s %2s %2s\n", STS_BIT(regs, AE), STS_BIT(regs, A2), STS_BIT(regs, A1), STS_BIT(regs, E2), STS_BIT(regs, E1)); pr_info("BTA: 0x%08lx\t SP: 0x%08lx\t FP: 0x%08lx\n", regs->bta, regs->sp, regs->fp); pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n", regs->lp_start, regs->lp_end, regs->lp_count); /* print regs->r0 thru regs->r12 * Sequential printing was generating horrible code */ print_reg_file(&(regs->r0), 0); /* If Callee regs were saved, display them too */ cregs = (struct callee_regs *)current->thread.callee_reg; if (cregs) show_callee_regs(cregs); free_page((unsigned long)buf); } void show_kernel_fault_diag(const char *str, struct pt_regs *regs, unsigned long address) { current->thread.fault_address = address; /* Caller and Callee regs */ show_regs(regs); /* Show stack trace if this Fatality happened in kernel mode */ if (!user_mode(regs)) show_stacktrace(current, regs); } #ifdef CONFIG_DEBUG_FS #include <linux/module.h> #include <linux/fs.h> #include <linux/mount.h> #include <linux/pagemap.h> #include <linux/init.h> #include <linux/namei.h> #include <linux/debugfs.h> static struct dentry *test_dentry; static struct dentry *test_dir; static struct dentry *test_u32_dentry; static u32 clr_on_read = 1; #ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT u32 numitlb, numdtlb, num_pte_not_present; static int fill_display_data(char *kbuf) { size_t num = 0; num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb); num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb); num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present); if (clr_on_read) numitlb = numdtlb = num_pte_not_present = 0; return num; } static int tlb_stats_open(struct inode *inode, struct file *file) { file->private_data = (void *)__get_free_page(GFP_KERNEL); return 0; } /* called on user read(): display the couters */ static ssize_t tlb_stats_output(struct file *file, /* file descriptor */ char __user *user_buf, /* user buffer */ size_t len, /* length of buffer */ loff_t *offset) /* offset in the file */ { size_t num; char *kbuf = (char *)file->private_data; /* All of the data can he shoved in one iteration */ if (*offset != 0) return 0; num = fill_display_data(kbuf); /* simple_read_from_buffer() is helper for copy to user space It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset @3 (offset) into the user space address starting at @1 (user_buf). @5 (len) is max size of user buffer */ return simple_read_from_buffer(user_buf, num, offset, kbuf, len); } /* called on user write : clears the counters */ static ssize_t tlb_stats_clear(struct file *file, const char __user *user_buf, size_t length, loff_t *offset) { numitlb = numdtlb = num_pte_not_present = 0; return length; } static int tlb_stats_close(struct inode *inode, struct file *file) { free_page((unsigned long)(file->private_data)); return 0; } static const struct file_operations tlb_stats_file_ops = { .read = tlb_stats_output, .write = tlb_stats_clear, .open = tlb_stats_open, .release = tlb_stats_close }; #endif static int __init arc_debugfs_init(void) { test_dir = debugfs_create_dir("arc", NULL); #ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL, &tlb_stats_file_ops); #endif test_u32_dentry = debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read); return 0; } module_init(arc_debugfs_init); static void __exit arc_debugfs_exit(void) { debugfs_remove(test_u32_dentry); debugfs_remove(test_dentry); debugfs_remove(test_dir); } module_exit(arc_debugfs_exit); #endif