^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 2009 Matt Fleming <matt@console-pimps.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * This is an implementation of a DWARF unwinder. Its main purpose is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * for generating stacktrace information. Based on the DWARF 3
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * specification from http://www.dwarfstd.org.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * TODO:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * - DWARF64 doesn't work.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * - Registers with DWARF_VAL_OFFSET rules aren't handled properly.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) /* #define DEBUG */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/list.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/mempool.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/mm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/elf.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/ftrace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <asm/dwarf.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <asm/unwinder.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <asm/sections.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <asm/unaligned.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) #include <asm/stacktrace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) /* Reserve enough memory for two stack frames */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #define DWARF_FRAME_MIN_REQ 2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) /* ... with 4 registers per frame. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #define DWARF_REG_MIN_REQ (DWARF_FRAME_MIN_REQ * 4)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) static struct kmem_cache *dwarf_frame_cachep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) static mempool_t *dwarf_frame_pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) static struct kmem_cache *dwarf_reg_cachep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) static mempool_t *dwarf_reg_pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) static struct rb_root cie_root;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) static DEFINE_SPINLOCK(dwarf_cie_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) static struct rb_root fde_root;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) static DEFINE_SPINLOCK(dwarf_fde_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) static struct dwarf_cie *cached_cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) static unsigned int dwarf_unwinder_ready;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * dwarf_frame_alloc_reg - allocate memory for a DWARF register
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) * @frame: the DWARF frame whose list of registers we insert on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) * @reg_num: the register number
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) * Allocate space for, and initialise, a dwarf reg from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * dwarf_reg_pool and insert it onto the (unsorted) linked-list of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) * dwarf registers for @frame.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) * Return the initialised DWARF reg.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) static struct dwarf_reg *dwarf_frame_alloc_reg(struct dwarf_frame *frame,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) unsigned int reg_num)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) struct dwarf_reg *reg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) reg = mempool_alloc(dwarf_reg_pool, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) if (!reg) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) printk(KERN_WARNING "Unable to allocate a DWARF register\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) * Let's just bomb hard here, we have no way to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) * gracefully recover.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) reg->number = reg_num;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) reg->addr = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) reg->flags = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) list_add(®->link, &frame->reg_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) return reg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) static void dwarf_frame_free_regs(struct dwarf_frame *frame)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) struct dwarf_reg *reg, *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) list_for_each_entry_safe(reg, n, &frame->reg_list, link) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) list_del(®->link);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) mempool_free(reg, dwarf_reg_pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) * dwarf_frame_reg - return a DWARF register
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) * @frame: the DWARF frame to search in for @reg_num
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) * @reg_num: the register number to search for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) * Lookup and return the dwarf reg @reg_num for this frame. Return
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) * NULL if @reg_num is an register invalid number.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static struct dwarf_reg *dwarf_frame_reg(struct dwarf_frame *frame,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) unsigned int reg_num)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) struct dwarf_reg *reg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) list_for_each_entry(reg, &frame->reg_list, link) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) if (reg->number == reg_num)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) return reg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) * dwarf_read_addr - read dwarf data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) * @src: source address of data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) * @dst: destination address to store the data to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * Read 'n' bytes from @src, where 'n' is the size of an address on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) * the native machine. We return the number of bytes read, which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) * should always be 'n'. We also have to be careful when reading
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) * from @src and writing to @dst, because they can be arbitrarily
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) * aligned. Return 'n' - the number of bytes read.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) static inline int dwarf_read_addr(unsigned long *src, unsigned long *dst)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) u32 val = get_unaligned(src);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) put_unaligned(val, dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) return sizeof(unsigned long *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) * dwarf_read_uleb128 - read unsigned LEB128 data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) * @addr: the address where the ULEB128 data is stored
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) * @ret: address to store the result
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) * Decode an unsigned LEB128 encoded datum. The algorithm is taken
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) * from Appendix C of the DWARF 3 spec. For information on the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) * encodings refer to section "7.6 - Variable Length Data". Return
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) * the number of bytes read.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) static inline unsigned long dwarf_read_uleb128(char *addr, unsigned int *ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) unsigned int result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) unsigned char byte;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) int shift, count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) result = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) shift = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) count = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) byte = __raw_readb(addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) addr++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) count++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) result |= (byte & 0x7f) << shift;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) shift += 7;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) if (!(byte & 0x80))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) *ret = result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) * dwarf_read_leb128 - read signed LEB128 data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) * @addr: the address of the LEB128 encoded data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) * @ret: address to store the result
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) * Decode signed LEB128 data. The algorithm is taken from Appendix
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) * C of the DWARF 3 spec. Return the number of bytes read.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) static inline unsigned long dwarf_read_leb128(char *addr, int *ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) unsigned char byte;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) int result, shift;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) int num_bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) int count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) result = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) shift = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) count = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) byte = __raw_readb(addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) addr++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) result |= (byte & 0x7f) << shift;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) shift += 7;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) count++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) if (!(byte & 0x80))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) /* The number of bits in a signed integer. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) num_bits = 8 * sizeof(result);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) if ((shift < num_bits) && (byte & 0x40))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) result |= (-1 << shift);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) *ret = result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) * dwarf_read_encoded_value - return the decoded value at @addr
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) * @addr: the address of the encoded value
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) * @val: where to write the decoded value
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) * @encoding: the encoding with which we can decode @addr
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) * GCC emits encoded address in the .eh_frame FDE entries. Decode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) * the value at @addr using @encoding. The decoded value is written
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) * to @val and the number of bytes read is returned.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) static int dwarf_read_encoded_value(char *addr, unsigned long *val,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) char encoding)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) unsigned long decoded_addr = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) int count = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) switch (encoding & 0x70) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) case DW_EH_PE_absptr:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) case DW_EH_PE_pcrel:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) decoded_addr = (unsigned long)addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) pr_debug("encoding=0x%x\n", (encoding & 0x70));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) if ((encoding & 0x07) == 0x00)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) encoding |= DW_EH_PE_udata4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) switch (encoding & 0x0f) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) case DW_EH_PE_sdata4:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) case DW_EH_PE_udata4:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) count += 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) decoded_addr += get_unaligned((u32 *)addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) __raw_writel(decoded_addr, val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) pr_debug("encoding=0x%x\n", encoding);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) * dwarf_entry_len - return the length of an FDE or CIE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) * @addr: the address of the entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) * @len: the length of the entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) * Read the initial_length field of the entry and store the size of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) * the entry in @len. We return the number of bytes read. Return a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) * count of 0 on error.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) static inline int dwarf_entry_len(char *addr, unsigned long *len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) u32 initial_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) int count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) initial_len = get_unaligned((u32 *)addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) count = 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) * An initial length field value in the range DW_LEN_EXT_LO -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) * DW_LEN_EXT_HI indicates an extension, and should not be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) * interpreted as a length. The only extension that we currently
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) * understand is the use of DWARF64 addresses.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) if (initial_len >= DW_EXT_LO && initial_len <= DW_EXT_HI) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) * The 64-bit length field immediately follows the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) * compulsory 32-bit length field.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) if (initial_len == DW_EXT_DWARF64) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) *len = get_unaligned((u64 *)addr + 4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) count = 12;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) printk(KERN_WARNING "Unknown DWARF extension\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) count = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) *len = initial_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) * dwarf_lookup_cie - locate the cie
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) * @cie_ptr: pointer to help with lookup
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) static struct dwarf_cie *dwarf_lookup_cie(unsigned long cie_ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) struct rb_node **rb_node = &cie_root.rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) struct dwarf_cie *cie = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) spin_lock_irqsave(&dwarf_cie_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) * We've cached the last CIE we looked up because chances are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) * that the FDE wants this CIE.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) if (cached_cie && cached_cie->cie_pointer == cie_ptr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) cie = cached_cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) while (*rb_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) struct dwarf_cie *cie_tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) cie_tmp = rb_entry(*rb_node, struct dwarf_cie, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) BUG_ON(!cie_tmp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) if (cie_ptr == cie_tmp->cie_pointer) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) cie = cie_tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) cached_cie = cie_tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) if (cie_ptr < cie_tmp->cie_pointer)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) rb_node = &(*rb_node)->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) rb_node = &(*rb_node)->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) spin_unlock_irqrestore(&dwarf_cie_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) return cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) * dwarf_lookup_fde - locate the FDE that covers pc
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) * @pc: the program counter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) struct dwarf_fde *dwarf_lookup_fde(unsigned long pc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) struct rb_node **rb_node = &fde_root.rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) struct dwarf_fde *fde = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) spin_lock_irqsave(&dwarf_fde_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) while (*rb_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) struct dwarf_fde *fde_tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) unsigned long tmp_start, tmp_end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) fde_tmp = rb_entry(*rb_node, struct dwarf_fde, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) BUG_ON(!fde_tmp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) tmp_start = fde_tmp->initial_location;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) tmp_end = fde_tmp->initial_location + fde_tmp->address_range;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) if (pc < tmp_start) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) rb_node = &(*rb_node)->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) if (pc < tmp_end) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) fde = fde_tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) rb_node = &(*rb_node)->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) spin_unlock_irqrestore(&dwarf_fde_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) return fde;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) * dwarf_cfa_execute_insns - execute instructions to calculate a CFA
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) * @insn_start: address of the first instruction
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) * @insn_end: address of the last instruction
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) * @cie: the CIE for this function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) * @fde: the FDE for this function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) * @frame: the instructions calculate the CFA for this frame
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) * @pc: the program counter of the address we're interested in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) * Execute the Call Frame instruction sequence starting at
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) * @insn_start and ending at @insn_end. The instructions describe
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) * how to calculate the Canonical Frame Address of a stackframe.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) * Store the results in @frame.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) static int dwarf_cfa_execute_insns(unsigned char *insn_start,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) unsigned char *insn_end,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) struct dwarf_cie *cie,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) struct dwarf_fde *fde,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) struct dwarf_frame *frame,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) unsigned long pc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) unsigned char insn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) unsigned char *current_insn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) unsigned int count, delta, reg, expr_len, offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) struct dwarf_reg *regp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) current_insn = insn_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) while (current_insn < insn_end && frame->pc <= pc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) insn = __raw_readb(current_insn++);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) * Firstly, handle the opcodes that embed their operands
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) * in the instructions.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) switch (DW_CFA_opcode(insn)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) case DW_CFA_advance_loc:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) delta = DW_CFA_operand(insn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) delta *= cie->code_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) frame->pc += delta;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) /* NOTREACHED */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) case DW_CFA_offset:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) reg = DW_CFA_operand(insn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) count = dwarf_read_uleb128(current_insn, &offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) offset *= cie->data_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) regp = dwarf_frame_alloc_reg(frame, reg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) regp->addr = offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) regp->flags |= DWARF_REG_OFFSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) /* NOTREACHED */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) case DW_CFA_restore:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) reg = DW_CFA_operand(insn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) /* NOTREACHED */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) * Secondly, handle the opcodes that don't embed their
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) * operands in the instruction.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) switch (insn) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) case DW_CFA_nop:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) case DW_CFA_advance_loc1:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) delta = *current_insn++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) frame->pc += delta * cie->code_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) case DW_CFA_advance_loc2:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) delta = get_unaligned((u16 *)current_insn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) current_insn += 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) frame->pc += delta * cie->code_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) case DW_CFA_advance_loc4:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) delta = get_unaligned((u32 *)current_insn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) current_insn += 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) frame->pc += delta * cie->code_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) case DW_CFA_offset_extended:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) count = dwarf_read_uleb128(current_insn, ®);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) count = dwarf_read_uleb128(current_insn, &offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) offset *= cie->data_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) case DW_CFA_restore_extended:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) count = dwarf_read_uleb128(current_insn, ®);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) case DW_CFA_undefined:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) count = dwarf_read_uleb128(current_insn, ®);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) regp = dwarf_frame_alloc_reg(frame, reg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) regp->flags |= DWARF_UNDEFINED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) case DW_CFA_def_cfa:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) count = dwarf_read_uleb128(current_insn,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) &frame->cfa_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) count = dwarf_read_uleb128(current_insn,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) &frame->cfa_offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) frame->flags |= DWARF_FRAME_CFA_REG_OFFSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) case DW_CFA_def_cfa_register:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) count = dwarf_read_uleb128(current_insn,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) &frame->cfa_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) frame->flags |= DWARF_FRAME_CFA_REG_OFFSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) case DW_CFA_def_cfa_offset:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) count = dwarf_read_uleb128(current_insn, &offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) frame->cfa_offset = offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) case DW_CFA_def_cfa_expression:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) count = dwarf_read_uleb128(current_insn, &expr_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) frame->cfa_expr = current_insn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) frame->cfa_expr_len = expr_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) current_insn += expr_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) frame->flags |= DWARF_FRAME_CFA_REG_EXP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) case DW_CFA_offset_extended_sf:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) count = dwarf_read_uleb128(current_insn, ®);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) count = dwarf_read_leb128(current_insn, &offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) offset *= cie->data_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) regp = dwarf_frame_alloc_reg(frame, reg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) regp->flags |= DWARF_REG_OFFSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) regp->addr = offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) case DW_CFA_val_offset:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) count = dwarf_read_uleb128(current_insn, ®);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) count = dwarf_read_leb128(current_insn, &offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) offset *= cie->data_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) regp = dwarf_frame_alloc_reg(frame, reg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) regp->flags |= DWARF_VAL_OFFSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) regp->addr = offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) case DW_CFA_GNU_args_size:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) count = dwarf_read_uleb128(current_insn, &offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) case DW_CFA_GNU_negative_offset_extended:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) count = dwarf_read_uleb128(current_insn, ®);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) current_insn += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) count = dwarf_read_uleb128(current_insn, &offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) offset *= cie->data_alignment_factor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) regp = dwarf_frame_alloc_reg(frame, reg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) regp->flags |= DWARF_REG_OFFSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) regp->addr = -offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) pr_debug("unhandled DWARF instruction 0x%x\n", insn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) * dwarf_free_frame - free the memory allocated for @frame
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) * @frame: the frame to free
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) void dwarf_free_frame(struct dwarf_frame *frame)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) dwarf_frame_free_regs(frame);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) mempool_free(frame, dwarf_frame_pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) extern void ret_from_irq(void);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) * dwarf_unwind_stack - unwind the stack
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) * @pc: address of the function to unwind
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) * @prev: struct dwarf_frame of the previous stackframe on the callstack
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) * Return a struct dwarf_frame representing the most recent frame
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) * on the callstack. Each of the lower (older) stack frames are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) * linked via the "prev" member.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) struct dwarf_frame *dwarf_unwind_stack(unsigned long pc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) struct dwarf_frame *prev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) struct dwarf_frame *frame;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) struct dwarf_cie *cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) struct dwarf_fde *fde;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) struct dwarf_reg *reg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) unsigned long addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) * If we've been called in to before initialization has
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) * completed, bail out immediately.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) if (!dwarf_unwinder_ready)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) * If we're starting at the top of the stack we need get the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) * contents of a physical register to get the CFA in order to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) * begin the virtual unwinding of the stack.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) * NOTE: the return address is guaranteed to be setup by the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) * time this function makes its first function call.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) if (!pc || !prev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) pc = _THIS_IP_;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) #ifdef CONFIG_FUNCTION_GRAPH_TRACER
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) * If our stack has been patched by the function graph tracer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) * then we might see the address of return_to_handler() where we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) * expected to find the real return address.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) if (pc == (unsigned long)&return_to_handler) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) struct ftrace_ret_stack *ret_stack;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) ret_stack = ftrace_graph_get_ret_stack(current, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) if (ret_stack)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) pc = ret_stack->ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) * We currently have no way of tracking how many
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) * return_to_handler()'s we've seen. If there is more
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) * than one patched return address on our stack,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) * complain loudly.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) WARN_ON(ftrace_graph_get_ret_stack(current, 1));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) frame = mempool_alloc(dwarf_frame_pool, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) if (!frame) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) printk(KERN_ERR "Unable to allocate a dwarf frame\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) INIT_LIST_HEAD(&frame->reg_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) frame->flags = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631) frame->prev = prev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) frame->return_addr = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) fde = dwarf_lookup_fde(pc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) if (!fde) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) * This is our normal exit path. There are two reasons
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) * why we might exit here,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640) * a) pc has no asscociated DWARF frame info and so
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) * we don't know how to unwind this frame. This is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) * usually the case when we're trying to unwind a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) * frame that was called from some assembly code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) * that has no DWARF info, e.g. syscalls.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646) * b) the DEBUG info for pc is bogus. There's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) * really no way to distinguish this case from the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) * case above, which sucks because we could print a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) * warning here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) goto bail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) cie = dwarf_lookup_cie(fde->cie_pointer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) frame->pc = fde->initial_location;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) /* CIE initial instructions */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) dwarf_cfa_execute_insns(cie->initial_instructions,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) cie->instructions_end, cie, fde,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) frame, pc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) /* FDE instructions */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) dwarf_cfa_execute_insns(fde->instructions, fde->end, cie,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) fde, frame, pc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) /* Calculate the CFA */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) switch (frame->flags) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) case DWARF_FRAME_CFA_REG_OFFSET:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) if (prev) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) reg = dwarf_frame_reg(prev, frame->cfa_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) UNWINDER_BUG_ON(!reg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) UNWINDER_BUG_ON(reg->flags != DWARF_REG_OFFSET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) addr = prev->cfa + reg->addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) frame->cfa = __raw_readl(addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) * Again, we're starting from the top of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) * stack. We need to physically read
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) * the contents of a register in order to get
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) * the Canonical Frame Address for this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) * function.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) frame->cfa = dwarf_read_arch_reg(frame->cfa_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) frame->cfa += frame->cfa_offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) reg = dwarf_frame_reg(frame, DWARF_ARCH_RA_REG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) * If we haven't seen the return address register or the return
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) * address column is undefined then we must assume that this is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) * the end of the callstack.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) if (!reg || reg->flags == DWARF_UNDEFINED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703) goto bail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) UNWINDER_BUG_ON(reg->flags != DWARF_REG_OFFSET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) addr = frame->cfa + reg->addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708) frame->return_addr = __raw_readl(addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) * Ah, the joys of unwinding through interrupts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) * Interrupts are tricky - the DWARF info needs to be _really_
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) * accurate and unfortunately I'm seeing a lot of bogus DWARF
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) * info. For example, I've seen interrupts occur in epilogues
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) * just after the frame pointer (r14) had been restored. The
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) * problem was that the DWARF info claimed that the CFA could be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) * reached by using the value of the frame pointer before it was
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) * restored.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) * So until the compiler can be trusted to produce reliable
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) * DWARF info when it really matters, let's stop unwinding once
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) * we've calculated the function that was interrupted.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) if (prev && prev->pc == (unsigned long)ret_from_irq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) frame->return_addr = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) return frame;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) bail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) dwarf_free_frame(frame);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) static int dwarf_parse_cie(void *entry, void *p, unsigned long len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) unsigned char *end, struct module *mod)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) struct rb_node **rb_node = &cie_root.rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) struct rb_node *parent = *rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) struct dwarf_cie *cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) int count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) cie = kzalloc(sizeof(*cie), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) if (!cie)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) cie->length = len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) * Record the offset into the .eh_frame section
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) * for this CIE. It allows this CIE to be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) * quickly and easily looked up from the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) * corresponding FDE.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) cie->cie_pointer = (unsigned long)entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758) cie->version = *(char *)p++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) UNWINDER_BUG_ON(cie->version != 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) cie->augmentation = p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) p += strlen(cie->augmentation) + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) count = dwarf_read_uleb128(p, &cie->code_alignment_factor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) p += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) count = dwarf_read_leb128(p, &cie->data_alignment_factor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) p += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) * Which column in the rule table contains the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) * return address?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) if (cie->version == 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) cie->return_address_reg = __raw_readb(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) p++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) count = dwarf_read_uleb128(p, &cie->return_address_reg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) p += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782) if (cie->augmentation[0] == 'z') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) unsigned int length, count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) cie->flags |= DWARF_CIE_Z_AUGMENTATION;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) count = dwarf_read_uleb128(p, &length);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) p += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) UNWINDER_BUG_ON((unsigned char *)p > end);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) cie->initial_instructions = p + length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) cie->augmentation++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) while (*cie->augmentation) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) * "L" indicates a byte showing how the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) * LSDA pointer is encoded. Skip it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) if (*cie->augmentation == 'L') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) p++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) cie->augmentation++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803) } else if (*cie->augmentation == 'R') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) * "R" indicates a byte showing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) * how FDE addresses are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) * encoded.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) cie->encoding = *(char *)p++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) cie->augmentation++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) } else if (*cie->augmentation == 'P') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) * "R" indicates a personality
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) * routine in the CIE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815) * augmentation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) } else if (*cie->augmentation == 'S') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) UNWINDER_BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822) * Unknown augmentation. Assume
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) * 'z' augmentation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) p = cie->initial_instructions;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) UNWINDER_BUG_ON(!p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) cie->initial_instructions = p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) cie->instructions_end = end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) /* Add to list */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) spin_lock_irqsave(&dwarf_cie_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) while (*rb_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838) struct dwarf_cie *cie_tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) cie_tmp = rb_entry(*rb_node, struct dwarf_cie, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842) parent = *rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844) if (cie->cie_pointer < cie_tmp->cie_pointer)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) rb_node = &parent->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846) else if (cie->cie_pointer >= cie_tmp->cie_pointer)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) rb_node = &parent->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849) WARN_ON(1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852) rb_link_node(&cie->node, parent, rb_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) rb_insert_color(&cie->node, &cie_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855) #ifdef CONFIG_MODULES
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856) if (mod != NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) list_add_tail(&cie->link, &mod->arch.cie_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) spin_unlock_irqrestore(&dwarf_cie_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 862) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 863) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 864)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) static int dwarf_parse_fde(void *entry, u32 entry_type,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866) void *start, unsigned long len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) unsigned char *end, struct module *mod)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) struct rb_node **rb_node = &fde_root.rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870) struct rb_node *parent = *rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) struct dwarf_fde *fde;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872) struct dwarf_cie *cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) int count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) void *p = start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877) fde = kzalloc(sizeof(*fde), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) if (!fde)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) fde->length = len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884) * In a .eh_frame section the CIE pointer is the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885) * delta between the address within the FDE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887) fde->cie_pointer = (unsigned long)(p - entry_type - 4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889) cie = dwarf_lookup_cie(fde->cie_pointer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890) fde->cie = cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892) if (cie->encoding)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) count = dwarf_read_encoded_value(p, &fde->initial_location,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894) cie->encoding);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896) count = dwarf_read_addr(p, &fde->initial_location);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898) p += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 900) if (cie->encoding)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 901) count = dwarf_read_encoded_value(p, &fde->address_range,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 902) cie->encoding & 0x0f);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904) count = dwarf_read_addr(p, &fde->address_range);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906) p += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) if (fde->cie->flags & DWARF_CIE_Z_AUGMENTATION) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909) unsigned int length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910) count = dwarf_read_uleb128(p, &length);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) p += count + length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914) /* Call frame instructions. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915) fde->instructions = p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916) fde->end = end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) /* Add to list. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919) spin_lock_irqsave(&dwarf_fde_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) while (*rb_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) struct dwarf_fde *fde_tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) unsigned long tmp_start, tmp_end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) unsigned long start, end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) fde_tmp = rb_entry(*rb_node, struct dwarf_fde, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) start = fde->initial_location;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929) end = fde->initial_location + fde->address_range;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) tmp_start = fde_tmp->initial_location;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932) tmp_end = fde_tmp->initial_location + fde_tmp->address_range;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) parent = *rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936) if (start < tmp_start)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937) rb_node = &parent->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) else if (start >= tmp_end)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) rb_node = &parent->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941) WARN_ON(1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944) rb_link_node(&fde->node, parent, rb_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945) rb_insert_color(&fde->node, &fde_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947) #ifdef CONFIG_MODULES
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948) if (mod != NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) list_add_tail(&fde->link, &mod->arch.fde_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952) spin_unlock_irqrestore(&dwarf_fde_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) static void dwarf_unwinder_dump(struct task_struct *task,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958) struct pt_regs *regs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) unsigned long *sp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960) const struct stacktrace_ops *ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961) void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963) struct dwarf_frame *frame, *_frame;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) unsigned long return_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) _frame = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967) return_addr = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970) frame = dwarf_unwind_stack(return_addr, _frame);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972) if (_frame)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) dwarf_free_frame(_frame);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 975) _frame = frame;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 976)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 977) if (!frame || !frame->return_addr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 978) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 979)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 980) return_addr = frame->return_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 981) ops->address(data, return_addr, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 982) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 983)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 984) if (frame)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 985) dwarf_free_frame(frame);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 986) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 987)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 988) static struct unwinder dwarf_unwinder = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 989) .name = "dwarf-unwinder",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 990) .dump = dwarf_unwinder_dump,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 991) .rating = 150,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 992) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 993)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 994) static void __init dwarf_unwinder_cleanup(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 995) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 996) struct dwarf_fde *fde, *next_fde;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 997) struct dwarf_cie *cie, *next_cie;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 998)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 999) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1000) * Deallocate all the memory allocated for the DWARF unwinder.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1001) * Traverse all the FDE/CIE lists and remove and free all the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1002) * memory associated with those data structures.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1003) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1004) rbtree_postorder_for_each_entry_safe(fde, next_fde, &fde_root, node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1005) kfree(fde);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1006)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1007) rbtree_postorder_for_each_entry_safe(cie, next_cie, &cie_root, node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1008) kfree(cie);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1009)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1010) mempool_destroy(dwarf_reg_pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1011) mempool_destroy(dwarf_frame_pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1012) kmem_cache_destroy(dwarf_reg_cachep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1013) kmem_cache_destroy(dwarf_frame_cachep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1014) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1015)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1016) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1017) * dwarf_parse_section - parse DWARF section
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1018) * @eh_frame_start: start address of the .eh_frame section
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1019) * @eh_frame_end: end address of the .eh_frame section
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1020) * @mod: the kernel module containing the .eh_frame section
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1021) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1022) * Parse the information in a .eh_frame section.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1023) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1024) static int dwarf_parse_section(char *eh_frame_start, char *eh_frame_end,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1025) struct module *mod)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1026) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1027) u32 entry_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1028) void *p, *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1029) int count, err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1030) unsigned long len = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1031) unsigned int c_entries, f_entries;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1032) unsigned char *end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1033)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1034) c_entries = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1035) f_entries = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1036) entry = eh_frame_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1037)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1038) while ((char *)entry < eh_frame_end) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1039) p = entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1040)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1041) count = dwarf_entry_len(p, &len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1042) if (count == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1043) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1044) * We read a bogus length field value. There is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1045) * nothing we can do here apart from disabling
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1046) * the DWARF unwinder. We can't even skip this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1047) * entry and move to the next one because 'len'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1048) * tells us where our next entry is.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1049) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1050) err = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1051) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1052) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1053) p += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1054)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1055) /* initial length does not include itself */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1056) end = p + len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1057)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1058) entry_type = get_unaligned((u32 *)p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1059) p += 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1060)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1061) if (entry_type == DW_EH_FRAME_CIE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1062) err = dwarf_parse_cie(entry, p, len, end, mod);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1063) if (err < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1064) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1065) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1066) c_entries++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1067) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1068) err = dwarf_parse_fde(entry, entry_type, p, len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1069) end, mod);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1070) if (err < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1071) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1072) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1073) f_entries++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1074) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1075)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1076) entry = (char *)entry + len + 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1077) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1078)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1079) printk(KERN_INFO "DWARF unwinder initialised: read %u CIEs, %u FDEs\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1080) c_entries, f_entries);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1081)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1082) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1083)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1084) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1085) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1086) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1087)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1088) #ifdef CONFIG_MODULES
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1089) int module_dwarf_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1090) struct module *me)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1091) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1092) unsigned int i, err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1093) unsigned long start, end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1094) char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1095)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1096) start = end = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1097)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1098) for (i = 1; i < hdr->e_shnum; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1099) /* Alloc bit cleared means "ignore it." */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1100) if ((sechdrs[i].sh_flags & SHF_ALLOC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1101) && !strcmp(secstrings+sechdrs[i].sh_name, ".eh_frame")) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1102) start = sechdrs[i].sh_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1103) end = start + sechdrs[i].sh_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1104) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1105) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1106) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1108) /* Did we find the .eh_frame section? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1109) if (i != hdr->e_shnum) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1110) INIT_LIST_HEAD(&me->arch.cie_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1111) INIT_LIST_HEAD(&me->arch.fde_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1112) err = dwarf_parse_section((char *)start, (char *)end, me);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1113) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1114) printk(KERN_WARNING "%s: failed to parse DWARF info\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1115) me->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1116) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1117) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1118) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1120) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1121) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1122)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1123) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1124) * module_dwarf_cleanup - remove FDE/CIEs associated with @mod
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1125) * @mod: the module that is being unloaded
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1126) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1127) * Remove any FDEs and CIEs from the global lists that came from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1128) * @mod's .eh_frame section because @mod is being unloaded.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1129) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1130) void module_dwarf_cleanup(struct module *mod)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1131) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1132) struct dwarf_fde *fde, *ftmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1133) struct dwarf_cie *cie, *ctmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1134) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1136) spin_lock_irqsave(&dwarf_cie_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1138) list_for_each_entry_safe(cie, ctmp, &mod->arch.cie_list, link) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1139) list_del(&cie->link);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1140) rb_erase(&cie->node, &cie_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1141) kfree(cie);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1142) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1144) spin_unlock_irqrestore(&dwarf_cie_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1145)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1146) spin_lock_irqsave(&dwarf_fde_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1148) list_for_each_entry_safe(fde, ftmp, &mod->arch.fde_list, link) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1149) list_del(&fde->link);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1150) rb_erase(&fde->node, &fde_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1151) kfree(fde);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1152) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1154) spin_unlock_irqrestore(&dwarf_fde_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1155) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1156) #endif /* CONFIG_MODULES */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1158) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1159) * dwarf_unwinder_init - initialise the dwarf unwinder
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1160) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1161) * Build the data structures describing the .dwarf_frame section to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1162) * make it easier to lookup CIE and FDE entries. Because the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1163) * .eh_frame section is packed as tightly as possible it is not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1164) * easy to lookup the FDE for a given PC, so we build a list of FDE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1165) * and CIE entries that make it easier.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1166) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1167) static int __init dwarf_unwinder_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1168) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1169) int err = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1171) dwarf_frame_cachep = kmem_cache_create("dwarf_frames",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1172) sizeof(struct dwarf_frame), 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1173) SLAB_PANIC | SLAB_HWCACHE_ALIGN, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1174)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1175) dwarf_reg_cachep = kmem_cache_create("dwarf_regs",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1176) sizeof(struct dwarf_reg), 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1177) SLAB_PANIC | SLAB_HWCACHE_ALIGN, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1178)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1179) dwarf_frame_pool = mempool_create_slab_pool(DWARF_FRAME_MIN_REQ,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1180) dwarf_frame_cachep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1181) if (!dwarf_frame_pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1182) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1183)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1184) dwarf_reg_pool = mempool_create_slab_pool(DWARF_REG_MIN_REQ,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1185) dwarf_reg_cachep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1186) if (!dwarf_reg_pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1187) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1189) err = dwarf_parse_section(__start_eh_frame, __stop_eh_frame, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1190) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1191) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1192)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1193) err = unwinder_register(&dwarf_unwinder);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1194) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1195) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1196)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1197) dwarf_unwinder_ready = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1198)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1199) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1200)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1201) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1202) printk(KERN_ERR "Failed to initialise DWARF unwinder: %d\n", err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1203) dwarf_unwinder_cleanup();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1204) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1205) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1206) early_initcall(dwarf_unwinder_init);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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