tegrakernel/kernel/nvidia/drivers/misc/tegra-profiler/dwarf_unwind.c

2257 lines
46 KiB
C

/*
* drivers/misc/tegra-profiler/dwarf_unwind.c
*
* Copyright (c) 2015-2018, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/err.h>
#include <asm/unaligned.h>
#include <linux/tegra_profiler.h>
#include "hrt.h"
#include "comm.h"
#include "backtrace.h"
#include "eh_unwind.h"
#include "dwarf.h"
#include "dwarf_unwind.h"
enum {
DW_WHERE_UNDEF, /* register isn't saved at all */
DW_WHERE_SAME, /* register has same value as in prev. frame */
DW_WHERE_CFAREL, /* register saved at CFA-relative address */
DW_WHERE_REG, /* register saved in another register */
DW_WHERE_EXPR, /* register saved */
DW_WHERE_VAL_OFFSET, /* value offset */
DW_WHERE_VAL_EXPR, /* register has computed value */
};
#define QUADD_AARCH64_REGISTERS 32
#define QUADD_AARCH32_REGISTERS 16
#define QUADD_NUM_REGS QUADD_AARCH64_REGISTERS
enum regs32 {
ARM32_FP_THUMB = 7,
ARM32_FP = 11,
ARM32_SP = 13,
ARM32_LR = 14,
ARM32_PC = 15
};
enum regs64 {
ARM64_FP = 29,
ARM64_LR = 30,
ARM64_SP = 31,
};
enum {
DW_MODE_ARM32,
DW_MODE_ARM64,
};
union dw_loc {
unsigned long reg;
long offset;
const unsigned char *exp;
};
struct reg_info {
int where;
union dw_loc loc;
};
enum {
DW_CFA_UNSET,
DW_CFA_REG_OFFSET,
DW_CFA_EXP,
};
struct dw_eh_frame_hdr {
unsigned char version;
unsigned char eh_frame_ptr_enc;
unsigned char fde_count_enc;
unsigned char table_enc;
};
struct dw_fde_table {
s32 initial_loc;
s32 fde;
};
struct regs_state {
struct reg_info reg[QUADD_NUM_REGS];
long cfa_offset;
int cfa_register;
unsigned char *cfa_expr;
unsigned int cfa_expr_len;
int cfa_how;
};
#define DW_MAX_RS_STACK_DEPTH 8
struct stackframe {
unsigned long pc;
unsigned long vregs[QUADD_NUM_REGS];
struct regs_state rs;
struct regs_state rs_initial;
unsigned long cfa;
int mode;
int is_sched;
};
struct dwarf_cpu_context {
struct regs_state rs_stack[DW_MAX_RS_STACK_DEPTH];
int depth;
struct stackframe sf;
int dw_ptr_size;
};
struct quadd_dwarf_context {
struct dwarf_cpu_context __percpu *cpu_ctx;
atomic_t started;
};
struct dw_cie {
unsigned long offset;
unsigned long length;
unsigned char *aug_string;
unsigned long aug_size;
unsigned char fde_encoding;
unsigned char lsda_encoding;
unsigned long code_align_factor;
long data_align_factor;
unsigned int initial_insn_len;
unsigned char *initial_insn;
int z_aug;
unsigned int retaddr_reg;
void *personality;
unsigned char *data;
};
struct dw_fde {
unsigned long offset;
unsigned long length;
unsigned long cie_pointer;
struct dw_cie *cie;
unsigned long initial_location;
unsigned long address_range;
unsigned int insn_length;
unsigned char *instructions;
unsigned char *data;
};
struct eh_sec_data {
size_t length;
unsigned char *data;
};
static struct quadd_dwarf_context ctx;
static inline int regnum_sp(int mode)
{
return (mode == DW_MODE_ARM32) ?
ARM32_SP : ARM64_SP;
}
static inline int regnum_fp(int mode)
{
return (mode == DW_MODE_ARM32) ?
ARM32_FP : ARM64_FP;
}
static inline int regnum_lr(int mode)
{
return (mode == DW_MODE_ARM32) ?
ARM32_LR : ARM64_LR;
}
static inline unsigned long
get_user_reg_size(int mode)
{
return (mode == DW_MODE_ARM32) ?
sizeof(u32) : sizeof(u64);
}
static inline int
get_secid_frame(int is_eh)
{
return is_eh ?
QUADD_SEC_TYPE_EH_FRAME :
QUADD_SEC_TYPE_DEBUG_FRAME;
}
static inline int
get_secid_frame_hdr(int is_eh)
{
return is_eh ?
QUADD_SEC_TYPE_EH_FRAME_HDR :
QUADD_SEC_TYPE_DEBUG_FRAME_HDR;
}
static inline int
is_frame_present(struct ex_region_info *ri, int is_eh)
{
struct extab_info *ti, *ti_hdr;
ti = &ri->mmap->fi.ex_sec[get_secid_frame(is_eh)];
ti_hdr = &ri->mmap->fi.ex_sec[get_secid_frame_hdr(is_eh)];
return (ti->length && ti_hdr->length) ? 1 : 0;
}
static inline int
validate_addr(struct ex_region_info *ri,
unsigned long addr,
unsigned long nbytes,
int st)
{
struct extab_info *ti;
struct quadd_mmap_area *mmap;
unsigned long start, end;
mmap = ri->mmap;
if (unlikely(!mmap)) {
pr_warn_once("%s: !mmap\n", __func__);
return 0;
}
if (atomic_read(&mmap->state) != QUADD_MMAP_STATE_ACTIVE)
return 0;
ti = &mmap->fi.ex_sec[st];
start = (unsigned long)mmap->data + ti->mmap_offset;
end = start + ti->length;
if (unlikely(addr < start || addr > end - nbytes)) {
pr_err_once("%s: error: addr: %#lx, len: %ld, data: %#lx-%#lx\n",
__func__, addr, nbytes, start, end);
return 0;
}
return 1;
}
static inline u8
read_mmap_data_u8(struct ex_region_info *ri,
const u8 *addr, int st, long *err)
{
unsigned long a = (unsigned long)addr;
if (unlikely(!validate_addr(ri, a, sizeof(*addr), st))) {
*err = -QUADD_URC_EACCESS;
return 0;
}
*err = 0;
return *addr;
}
static inline u16
read_mmap_data_u16(struct ex_region_info *ri,
const u16 *addr, int st, long *err)
{
unsigned long a = (unsigned long)addr;
if (unlikely(!validate_addr(ri, a, sizeof(*addr), st))) {
*err = -QUADD_URC_EACCESS;
return 0;
}
*err = 0;
return get_unaligned(addr);
}
static inline s16
read_mmap_data_s16(struct ex_region_info *ri,
const s16 *addr, int st, long *err)
{
unsigned long a = (unsigned long)addr;
if (unlikely(!validate_addr(ri, a, sizeof(*addr), st))) {
*err = -QUADD_URC_EACCESS;
return 0;
}
*err = 0;
return get_unaligned(addr);
}
static inline u32
read_mmap_data_u32(struct ex_region_info *ri,
const u32 *addr, int st, long *err)
{
unsigned long a = (unsigned long)addr;
if (unlikely(!validate_addr(ri, a, sizeof(*addr), st))) {
*err = -QUADD_URC_EACCESS;
return 0;
}
*err = 0;
return get_unaligned(addr);
}
static inline s32
read_mmap_data_s32(struct ex_region_info *ri,
const s32 *addr, int st, long *err)
{
unsigned long a = (unsigned long)addr;
if (unlikely(!validate_addr(ri, a, sizeof(*addr), st))) {
*err = -QUADD_URC_EACCESS;
return 0;
}
*err = 0;
return get_unaligned(addr);
}
static inline s64
read_mmap_data_s64(struct ex_region_info *ri,
const s64 *addr, int st, long *err)
{
unsigned long a = (unsigned long)addr;
if (unlikely(!validate_addr(ri, a, sizeof(*addr), st))) {
*err = -QUADD_URC_EACCESS;
return 0;
}
*err = 0;
return get_unaligned(addr);
}
static inline u64
read_mmap_data_u64(struct ex_region_info *ri,
const u64 *addr, int st, long *err)
{
unsigned long a = (unsigned long)addr;
if (unlikely(!validate_addr(ri, a, sizeof(*addr), st))) {
*err = -QUADD_URC_EACCESS;
return 0;
}
*err = 0;
return get_unaligned(addr);
}
static inline unsigned long
ex_addr_to_mmap_addr(unsigned long addr,
struct ex_region_info *ri, int st)
{
unsigned long offset;
struct extab_info *ti;
struct quadd_mmap_area *mmap;
mmap = ri->mmap;
if (unlikely(!mmap)) {
pr_warn_once("%s: !mmap\n", __func__);
return 0;
}
ti = &mmap->fi.ex_sec[st];
offset = addr - get_ex_sec_address(ri, ti, st);
pr_debug("addr: %#lx, data: %p, st: %d, ri vma: %#lx-%#lx\n",
addr, mmap->data, st, ri->vm_start, ri->vm_end);
pr_debug("ti addr/len/mmap_of:%#lx/%#lx/%#lx, offset:%#lx, res:%#lx\n",
ti->addr, ti->length, ti->mmap_offset,
offset, ti->mmap_offset + offset + (unsigned long)mmap->data);
return ti->mmap_offset + offset + (unsigned long)mmap->data;
}
static inline unsigned long
mmap_addr_to_ex_addr(unsigned long addr,
struct ex_region_info *ri, int st)
{
unsigned long offset;
struct extab_info *ti;
struct quadd_mmap_area *mmap;
mmap = ri->mmap;
if (unlikely(!mmap)) {
pr_warn_once("%s: !mmap\n", __func__);
return 0;
}
ti = &mmap->fi.ex_sec[st];
offset = addr - ti->mmap_offset - (unsigned long)mmap->data;
pr_debug("addr: %#lx, data: %p, st: %d, ri vma: %#lx-%#lx\n",
addr, mmap->data, st, ri->vm_start, ri->vm_end);
pr_debug("ti addr/len/mmap_of:%#lx/%#lx/%#lx, offset:%#lx, res:%#lx\n",
ti->addr, ti->length, ti->mmap_offset,
offset, get_ex_sec_address(ri, ti, st) + offset);
return get_ex_sec_address(ri, ti, st) + offset;
}
static int
get_section_index_by_address(struct ex_region_info *ri,
unsigned long addr)
{
int i;
struct extab_info *ti;
unsigned long start, end;
for (i = 0; i < ARRAY_SIZE(ri->mmap->fi.ex_sec); i++) {
ti = &ri->mmap->fi.ex_sec[i];
if (ti->length > 0) {
start = get_ex_sec_address(ri, ti, i);
end = start + ti->length;
if (addr >= start && addr < end)
return i;
}
}
return -QUADD_URC_IDX_NOT_FOUND;
}
static inline int validate_regnum(struct regs_state *rs, int regnum)
{
if (unlikely(regnum >= ARRAY_SIZE(rs->reg))) {
pr_err_once("error: invalid reg: %d\n", regnum);
return 0;
}
return 1;
}
static inline void
set_rule_offset(struct regs_state *rs, int regnum, int where, long offset)
{
struct reg_info *r;
if (!validate_regnum(rs, regnum))
return;
r = &rs->reg[regnum];
r->where = where;
r->loc.offset = offset;
}
static inline void __maybe_unused
set_rule_reg(struct regs_state *rs, int regnum, int where, unsigned long reg)
{
struct reg_info *r;
if (!validate_regnum(rs, regnum))
return;
r = &rs->reg[regnum];
r->where = where;
r->loc.reg = reg;
}
static inline void
set_rule_exp(struct regs_state *rs, int regnum,
int where, const unsigned char *exp)
{
struct reg_info *r;
if (!validate_regnum(rs, regnum))
return;
r = &rs->reg[regnum];
r->where = where;
r->loc.exp = exp;
}
static inline void
set_rule(struct regs_state *rs, int regnum, int where, long value)
{
set_rule_offset(rs, regnum, where, value);
}
static inline unsigned long
dw_bst_get_initial_loc(const struct dw_fde_table *fi,
unsigned long data_base)
{
return data_base + fi->initial_loc;
}
static inline unsigned long
dw_bst_get_fde_addr(const struct dw_fde_table *fi,
unsigned long data_base)
{
return data_base + fi->fde;
}
static inline unsigned long
dwarf_read_uleb128(struct ex_region_info *ri,
unsigned char *addr,
unsigned long *ret,
int st,
long *err)
{
unsigned long result;
unsigned char byte;
int shift, count;
result = 0;
shift = 0;
count = 0;
while (1) {
byte = read_mmap_data_u8(ri, addr, st, err);
if (*err)
return 0;
addr++;
count++;
result |= (byte & 0x7f) << shift;
shift += 7;
if (!(byte & 0x80))
break;
}
*ret = result;
return count;
}
static inline unsigned long
dwarf_read_sleb128(struct ex_region_info *ri,
unsigned char *addr,
long *ret,
int st,
long *err)
{
unsigned char byte;
long result, shift;
int num_bits;
int count;
result = 0;
shift = 0;
count = 0;
while (1) {
byte = read_mmap_data_u8(ri, addr, st, err);
if (*err)
return 0;
addr++;
result |= (byte & 0x7f) << shift;
shift += 7;
count++;
if (!(byte & 0x80))
break;
}
num_bits = 8 * sizeof(result);
if ((shift < num_bits) && (byte & 0x40))
result |= (-1L << shift);
*ret = result;
return count;
}
static inline unsigned int
dw_cfa_opcode(unsigned int insn)
{
return insn & 0xc0;
}
static inline unsigned int
dw_cfa_operand(unsigned int insn)
{
return insn & 0x3f;
}
static void
rules_cleanup(struct regs_state *rs, int mode)
{
int i, num_regs;
num_regs = (mode == DW_MODE_ARM32) ?
QUADD_AARCH32_REGISTERS :
QUADD_AARCH64_REGISTERS;
for (i = 0; i < num_regs; i++)
set_rule(rs, i, DW_WHERE_UNDEF, 0);
}
static int
dwarf_read_encoded_value(struct ex_region_info *ri,
void *addr,
void *pcrel_base,
unsigned long *val,
char encoding,
int st)
{
int dw_ptr_size, count = 0;
long stmp = 0, err = 0;
unsigned long utmp, res = 0;
struct dwarf_cpu_context *cpu_ctx = this_cpu_ptr(ctx.cpu_ctx);
pr_debug("encoding: %#x\n", encoding);
dw_ptr_size = cpu_ctx->dw_ptr_size;
if (encoding == DW_EH_PE_omit) {
pr_debug("DW_EH_PE_omit\n");
*val = 0;
return 0;
} else if (encoding == DW_EH_PE_aligned) {
unsigned long aligned = ALIGN((unsigned long)addr,
dw_ptr_size);
pr_debug("DW_EH_PE_aligned\n");
if (dw_ptr_size == 4) {
*val = read_mmap_data_u32(ri, (u32 *)aligned, st, &err);
} else if (dw_ptr_size == 8) {
*val = read_mmap_data_u64(ri, (u64 *)aligned, st, &err);
} else {
pr_err_once("%s: error: encoding\n", __func__);
return -QUADD_URC_TBL_IS_CORRUPT;
}
if (err)
return err;
return dw_ptr_size;
}
switch (encoding & 0x0f) {
case DW_EH_PE_absptr:
pr_debug("%s: absptr encoding\n", __func__);
if (dw_ptr_size == 4) {
*val = read_mmap_data_u32(ri, (u32 *)addr, st, &err);
} else if (dw_ptr_size == 8) {
*val = read_mmap_data_u64(ri, (u64 *)addr, st, &err);
} else {
pr_err_once("error: wrong dwarf size\n");
return -QUADD_URC_UNHANDLED_INSTRUCTION;
}
if (err)
return err;
return dw_ptr_size;
case DW_EH_PE_sdata2:
case DW_EH_PE_udata2:
pr_debug("encoding: DW_EH_PE_sdata2\n");
stmp = read_mmap_data_s16(ri, (s16 *)addr, st, &err);
if (err)
return err;
count += sizeof(s16);
break;
case DW_EH_PE_sdata4:
case DW_EH_PE_udata4:
pr_debug("encoding: DW_EH_PE_udata4/sdata4\n");
stmp = read_mmap_data_s32(ri, (s32 *)addr, st, &err);
if (err)
return err;
count += sizeof(s32);
break;
case DW_EH_PE_sdata8:
case DW_EH_PE_udata8:
pr_debug("encoding: DW_EH_PE_udata8\n");
stmp = read_mmap_data_s64(ri, (s64 *)addr, st, &err);
if (err)
return err;
count += sizeof(s64);
break;
case DW_EH_PE_uleb128:
pr_debug("encoding: DW_EH_PE_uleb128\n");
count += dwarf_read_uleb128(ri, addr, &utmp, st, &err);
if (err)
return err;
stmp = utmp;
break;
case DW_EH_PE_sleb128:
pr_debug("encoding: DW_EH_PE_sleb128\n");
count += dwarf_read_sleb128(ri, addr, &stmp, st, &err);
if (err)
return err;
break;
default:
pr_warn_once("%s: warning: encoding: %#x\n",
__func__, encoding & 0x0f);
return -QUADD_URC_UNHANDLED_INSTRUCTION;
}
switch (encoding & 0x70) {
case DW_EH_PE_absptr:
pr_debug("DW_EH_PE_absptr\n");
res = stmp;
break;
case DW_EH_PE_pcrel:
pr_debug("DW_EH_PE_pcrel, pcrel_base: %p, stmp: %ld\n",
pcrel_base, stmp);
res = (unsigned long)pcrel_base + stmp;
break;
case DW_EH_PE_textrel:
pr_warn_once("warning: DW_EH_PE_textrel\n");
return -QUADD_URC_UNHANDLED_INSTRUCTION;
case DW_EH_PE_datarel:
pr_warn_once("warning: DW_EH_PE_datarel\n");
return -QUADD_URC_UNHANDLED_INSTRUCTION;
case DW_EH_PE_funcrel:
pr_warn_once("warning: DW_EH_PE_funcrel\n");
return -QUADD_URC_UNHANDLED_INSTRUCTION;
default:
pr_warn_once("%s: warning: encoding: %#x\n",
__func__, encoding & 0x70);
return -QUADD_URC_UNHANDLED_INSTRUCTION;
}
if (res != 0) {
if (encoding & DW_EH_PE_indirect) {
int sec_idx;
pr_debug("DW_EH_PE_indirect, addr: %#lx\n", res);
sec_idx = get_section_index_by_address(ri, res);
if (sec_idx >= 0) {
if (dw_ptr_size == 4) {
res = read_mmap_data_u32(ri, (u32 *)res,
sec_idx, &err);
} else if (dw_ptr_size == 8) {
res = read_mmap_data_u64(ri, (u64 *)res,
sec_idx, &err);
} else {
return -QUADD_URC_UNHANDLED_INSTRUCTION;
}
if (err)
return err;
} else {
/* we ignore links to unloaded sections */
res = 0;
}
}
}
*val = res;
return count;
}
static long
dwarf_cfa_exec_insns(struct ex_region_info *ri,
unsigned char *insn_start,
unsigned char *insn_end,
struct dw_cie *cie,
struct stackframe *sf,
unsigned long pc,
int is_eh)
{
unsigned char insn;
unsigned char *c_insn;
unsigned int expr_len, delta, secid;
unsigned long utmp, reg;
long offset, stmp, err = 0;
struct regs_state *rs, *rs_initial, *rs_stack;
struct dwarf_cpu_context *cpu_ctx = this_cpu_ptr(ctx.cpu_ctx);
secid = get_secid_frame(is_eh);
rs = &sf->rs;
rs_initial = &sf->rs_initial;
rs_stack = cpu_ctx->rs_stack;
cpu_ctx->depth = 0;
c_insn = insn_start;
while (c_insn < insn_end && sf->pc <= pc) {
insn = read_mmap_data_u8(ri, c_insn++,
secid, &err);
if (err)
return err;
switch (dw_cfa_opcode(insn)) {
case DW_CFA_advance_loc:
delta = dw_cfa_operand(insn);
delta *= cie->code_align_factor;
sf->pc += delta;
pr_debug("DW_CFA_advance_loc: pc: %#lx --> %#lx (delta: %#x)\n",
sf->pc - delta, sf->pc, delta);
continue;
case DW_CFA_offset:
reg = dw_cfa_operand(insn);
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
offset = utmp * cie->data_align_factor;
set_rule_offset(rs, reg, DW_WHERE_CFAREL, offset);
pr_debug("DW_CFA_offset: reg: r%lu, offset(addr): %#lx (%ld)\n",
reg, offset, offset);
continue;
case DW_CFA_restore:
reg = dw_cfa_operand(insn);
if (!validate_regnum(rs, reg))
break;
rs->reg[reg] = rs_initial->reg[reg];
pr_debug("DW_CFA_restore: reg: r%lu\n", reg);
continue;
}
switch (insn) {
case DW_CFA_nop:
pr_debug("DW_CFA_nop\n");
continue;
case DW_CFA_advance_loc1:
delta = read_mmap_data_u8(ri, c_insn++,
secid, &err);
if (err)
return err;
sf->pc += delta * cie->code_align_factor;
pr_debug("DW_CFA_advance_loc1: pc: %#lx --> %#lx (delta: %#lx)\n",
sf->pc - delta * cie->code_align_factor, sf->pc,
delta * cie->code_align_factor);
break;
case DW_CFA_advance_loc2:
delta = read_mmap_data_u16(ri, (u16 *)c_insn,
secid, &err);
if (err)
return err;
c_insn += 2;
sf->pc += delta * cie->code_align_factor;
pr_debug("DW_CFA_advance_loc2: pc: %#lx --> %#lx (delta: %#lx)\n",
sf->pc - delta * cie->code_align_factor, sf->pc,
delta * cie->code_align_factor);
break;
case DW_CFA_advance_loc4:
delta = read_mmap_data_u32(ri, (u32 *)c_insn,
secid, &err);
if (err)
return err;
c_insn += 4;
sf->pc += delta * cie->code_align_factor;
pr_debug("DW_CFA_advance_loc4: pc: %#lx --> %#lx (delta: %#lx)\n",
sf->pc - delta * cie->code_align_factor, sf->pc,
delta * cie->code_align_factor);
break;
case DW_CFA_offset_extended:
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
reg = utmp;
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
offset = utmp * cie->data_align_factor;
pr_debug("DW_CFA_offset_extended: reg: r%lu, offset: %#lx\n",
reg, offset);
break;
case DW_CFA_restore_extended:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
pr_debug("DW_CFA_restore_extended: reg: r%lu\n", reg);
break;
case DW_CFA_undefined:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
set_rule(rs, reg, DW_WHERE_UNDEF, 0);
pr_debug("DW_CFA_undefined: reg: r%lu\n", reg);
break;
case DW_CFA_def_cfa:
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
rs->cfa_register = utmp;
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
rs->cfa_offset = utmp;
pr_debug("DW_CFA_def_cfa: cfa_register: r%u, cfa_offset: %ld (%#lx)\n",
rs->cfa_register, rs->cfa_offset,
rs->cfa_offset);
break;
case DW_CFA_def_cfa_register:
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
rs->cfa_register = utmp;
pr_debug("DW_CFA_def_cfa_register: cfa_register: r%u\n",
rs->cfa_register);
break;
case DW_CFA_def_cfa_offset:
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
rs->cfa_offset = utmp;
pr_debug("DW_CFA_def_cfa_offset: cfa_offset: %ld (%#lx)\n",
rs->cfa_offset, rs->cfa_offset);
break;
case DW_CFA_def_cfa_expression:
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
expr_len = utmp;
rs->cfa_expr = c_insn;
rs->cfa_expr_len = expr_len;
rs->cfa_how = DW_CFA_EXP;
c_insn += expr_len;
pr_debug("DW_CFA_def_cfa_expression: expr_len: %#x\n",
expr_len);
break;
case DW_CFA_expression:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
set_rule_exp(rs, reg, DW_WHERE_EXPR, c_insn);
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
c_insn += utmp;
pr_debug("DW_CFA_expression: reg: r%lu\n", reg);
break;
case DW_CFA_offset_extended_sf:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
c_insn += dwarf_read_sleb128(ri, c_insn, &stmp,
secid, &err);
if (err)
return err;
offset = stmp * cie->data_align_factor;
set_rule_offset(rs, reg, DW_WHERE_CFAREL, offset);
pr_debug("DW_CFA_offset_extended_sf: reg: r%lu, offset: %#lx\n",
reg, offset);
break;
case DW_CFA_val_offset:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
offset = utmp * cie->data_align_factor;
set_rule_offset(rs, reg, DW_WHERE_VAL_OFFSET, offset);
pr_debug("DW_CFA_val_offset: reg: r%lu, offset(addr): %#lx\n",
reg, offset);
break;
case DW_CFA_val_offset_sf:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
c_insn += dwarf_read_sleb128(ri, c_insn, &stmp,
secid, &err);
if (err)
return err;
offset = stmp * cie->data_align_factor;
set_rule_offset(rs, reg, DW_WHERE_VAL_OFFSET, offset);
pr_debug("DW_CFA_val_offset_sf: reg: r%lu, offset(addr): %#lx\n",
reg, offset);
break;
case DW_CFA_GNU_args_size:
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
pr_debug("DW_CFA_GNU_args_size: offset: %#lx\n", utmp);
break;
case DW_CFA_GNU_negative_offset_extended:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
offset = utmp * cie->data_align_factor;
set_rule_offset(rs, reg, DW_WHERE_CFAREL, -offset);
pr_debug("DW_CFA_GNU_negative_offset_extended: reg: r%lu, offset: %#lx\n",
reg, offset);
break;
case DW_CFA_remember_state:
pr_debug("DW_CFA_remember_state\n");
if (cpu_ctx->depth >= DW_MAX_RS_STACK_DEPTH) {
pr_warn_once("error: rs stack was overflowed\n");
return 0;
}
rs_stack[cpu_ctx->depth++] = *rs;
break;
case DW_CFA_restore_state:
pr_debug("DW_CFA_restore_state\n");
if (cpu_ctx->depth == 0) {
pr_warn_once("error: rs stack error\n");
return 0;
}
*rs = rs_stack[--cpu_ctx->depth];
break;
case DW_CFA_def_cfa_sf:
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
c_insn += dwarf_read_sleb128(ri, c_insn, &stmp,
secid, &err);
if (err)
return err;
rs->cfa_register = utmp;
rs->cfa_offset = stmp * cie->data_align_factor;
rs->cfa_how = DW_CFA_REG_OFFSET;
pr_debug("DW_CFA_def_cfa_sf: cfa_register: r%u, cfa_offset: %ld (%#lx)\n",
rs->cfa_register, rs->cfa_offset,
rs->cfa_offset);
break;
case DW_CFA_def_cfa_offset_sf:
c_insn += dwarf_read_sleb128(ri, c_insn, &stmp,
secid, &err);
if (err)
return err;
rs->cfa_offset = stmp * cie->data_align_factor;
pr_debug("DW_CFA_def_cfa_offset_sf: cfa_offset: %ld (%#lx)\n",
rs->cfa_offset, rs->cfa_offset);
break;
case DW_CFA_same_value:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
set_rule(rs, reg, DW_WHERE_SAME, 0);
pr_debug("DW_CFA_same_value: reg: r%lu\n", reg);
break;
case DW_CFA_val_expression:
c_insn += dwarf_read_uleb128(ri, c_insn, &reg,
secid, &err);
if (err)
return err;
set_rule_exp(rs, reg, DW_WHERE_VAL_EXPR, c_insn);
c_insn += dwarf_read_uleb128(ri, c_insn, &utmp,
secid, &err);
if (err)
return err;
c_insn += utmp;
pr_debug("DW_CFA_val_expression: reg: r%lu\n", reg);
break;
default:
pr_warn_once("warning: unhandled dwarf instr %#x\n",
insn);
break;
}
}
return 0;
}
static long
decode_cie_entry(struct ex_region_info *ri,
struct dw_cie *cie,
unsigned char *entry,
size_t length,
int is_eh)
{
long err;
unsigned long utmp;
unsigned char *p, *end, *aug;
unsigned int secid, cie_id;
unsigned int cie_version, id, len, max_len;
secid = get_secid_frame(is_eh);
p = entry;
end = entry + length;
p += sizeof(u32);
id = read_mmap_data_u32(ri, (u32 *)p, secid, &err);
if (err)
return err;
p += sizeof(u32);
cie_id = is_eh ? 0 : DW_CIE_ID;
if (id != cie_id) {
pr_err_once("error: incorrect cie_id");
return -QUADD_URC_TBL_IS_CORRUPT;
}
cie_version = read_mmap_data_u8(ri, p++, secid, &err);
if (err)
return err;
if (cie_version != 1 && cie_version != 3) {
pr_err_once("error: wrong cie_version: %u\n", cie_version);
return -QUADD_URC_TBL_IS_CORRUPT;
}
if (p >= end)
return -QUADD_URC_TBL_IS_CORRUPT;
max_len = end - p - 1;
len = strnlen((const char *)p, max_len);
if (len == max_len)
return -QUADD_URC_TBL_IS_CORRUPT;
cie->aug_string = p;
p += len + 1;
pr_debug("aug_string: %s\n", cie->aug_string);
p += dwarf_read_uleb128(ri, p, &cie->code_align_factor,
secid, &err);
if (err)
return err;
p += dwarf_read_sleb128(ri, p, &cie->data_align_factor,
secid, &err);
if (err)
return err;
if (cie_version == 1) {
cie->retaddr_reg = read_mmap_data_u8(ri, p++,
secid,
&err);
if (err)
return err;
} else {
p += dwarf_read_uleb128(ri, p, &utmp,
secid, &err);
if (err)
return err;
cie->retaddr_reg = utmp;
}
pr_debug("address column: %u\n", cie->retaddr_reg);
aug = cie->aug_string;
cie->z_aug = 0;
cie->initial_insn = NULL;
cie->initial_insn_len = 0;
if (*aug == 'z') {
p += dwarf_read_uleb128(ri, p, &cie->aug_size,
secid, &err);
if (err)
return err;
cie->initial_insn = p + cie->aug_size;
aug++;
cie->z_aug = 1;
}
cie->fde_encoding = 0;
cie->lsda_encoding = DW_EH_PE_omit;
cie->personality = NULL;
while (*aug != '\0') {
if (p >= end)
return -QUADD_URC_TBL_IS_CORRUPT;
if (*aug == 'L') {
cie->lsda_encoding =
read_mmap_data_u8(ri, p++,
secid,
&err);
if (err)
return err;
aug++;
} else if (*aug == 'R') {
cie->fde_encoding =
read_mmap_data_u8(ri, p++,
secid,
&err);
if (err)
return err;
aug++;
pr_debug("fde_encoding: %#x\n", cie->fde_encoding);
} else if (*aug == 'P') {
int cnt;
void *pcrel_base;
unsigned char handler_encoding;
unsigned long personality;
handler_encoding = *p++;
pcrel_base = (void *)
mmap_addr_to_ex_addr((unsigned long)p,
ri,
secid);
cnt = dwarf_read_encoded_value(ri, p, pcrel_base,
&personality,
handler_encoding,
secid);
if (cnt < 0) {
pr_err_once("%s: error: personality routine\n",
__func__);
return cnt;
}
p += cnt;
pr_debug("personality: %#lx\n", personality);
cie->personality = (void *)personality;
aug++;
} else if (*aug == 'S') {
aug++;
pr_debug("%s: aug: S\n", __func__);
} else {
pr_warn_once("%s: warning: unknown aug\n", __func__);
return -QUADD_URC_UNHANDLED_INSTRUCTION;
}
}
if (p > end) {
pr_err_once("%s: error: cie\n", __func__);
return -QUADD_URC_TBL_IS_CORRUPT;
}
if (p == end)
return 0;
if (!cie->initial_insn)
cie->initial_insn = p;
cie->initial_insn_len = end - cie->initial_insn;
return 0;
}
static long
decode_fde_entry(struct ex_region_info *ri,
struct dw_fde *fde,
unsigned char *entry,
size_t length,
int is_eh)
{
int count, secid;
long err = 0;
unsigned long utmp;
unsigned char *p, *end, *pcrel_base;
struct dw_cie *cie = fde->cie;
secid = get_secid_frame(is_eh);
p = entry;
end = entry + length;
p += sizeof(u32);
p += sizeof(u32);
pcrel_base = (unsigned char *)
mmap_addr_to_ex_addr((unsigned long)p, ri, secid);
count = dwarf_read_encoded_value(ri, p, pcrel_base,
&fde->initial_location,
cie->fde_encoding,
secid);
if (count < 0)
return count;
p += count;
fde->address_range = read_mmap_data_u32(ri, (u32 *)p,
secid, &err);
if (err)
return err;
p += sizeof(u32);
if (fde->initial_location < ri->vm_start)
fde->initial_location += ri->vm_start;
pr_debug("pcrel_base: %p\n", pcrel_base);
pr_debug("init location: %#lx\n", fde->initial_location);
pr_debug("address_range: %#lx\n", fde->address_range);
if (cie->z_aug) {
p += dwarf_read_uleb128(ri, p, &utmp,
secid, &err);
if (err)
return err;
p += utmp;
}
if (p > end) {
pr_err_once("%s: error: incorrect fde\n", __func__);
return -QUADD_URC_TBL_IS_CORRUPT;
}
fde->insn_length = end - p;
if (fde->insn_length > 0)
fde->instructions = p;
else
fde->instructions = NULL;
return 0;
}
static const struct dw_fde_table *
dwarf_bst_find_idx(unsigned long data_base,
struct dw_fde_table *fde_table,
unsigned long length,
unsigned long addr)
{
unsigned long initial_loc;
struct dw_fde_table *start, *stop;
struct dw_fde_table *mid = NULL;
if (unlikely(!length))
return NULL;
start = fde_table;
stop = start + length - 1;
initial_loc = dw_bst_get_initial_loc(start, data_base);
if (addr < initial_loc)
return NULL;
initial_loc = dw_bst_get_initial_loc(stop, data_base);
if (addr >= initial_loc)
return NULL;
while (start < stop - 1) {
mid = start + ((stop - start) >> 1);
initial_loc = dw_bst_get_initial_loc(mid, data_base);
if (addr < initial_loc)
stop = mid;
else
start = mid;
}
return start;
}
static struct dw_fde_table *
dwarf_get_bs_table(struct ex_region_info *ri,
void *data,
unsigned long length,
unsigned long data_base,
unsigned long *nr_entries,
int is_eh)
{
int count, secid_hdr;
unsigned char *p, *end;
struct dw_fde_table *bst;
unsigned long fde_count, frame_ptr;
struct dw_eh_frame_hdr *hdr = data;
if (length <= sizeof(*hdr))
return NULL;
end = data + length;
pr_debug("hdr: %p\n", hdr);
secid_hdr = get_secid_frame_hdr(is_eh);
if (hdr->version != 1) {
pr_warn_once("warning: unknown eh hdr format: %u\n",
(unsigned int)hdr->version);
return NULL;
}
p = (unsigned char *)(hdr + 1);
if (hdr->eh_frame_ptr_enc != DW_EH_PE_omit) {
count = dwarf_read_encoded_value(ri, p, (void *)data_base,
&frame_ptr,
hdr->eh_frame_ptr_enc,
secid_hdr);
if (count < 0)
return NULL;
p += count;
}
if (hdr->fde_count_enc == DW_EH_PE_omit)
return NULL;
count = dwarf_read_encoded_value(ri, p, (void *)data_base,
&fde_count, hdr->fde_count_enc,
secid_hdr);
if (count < 0)
return NULL;
p += count;
if (p >= end)
return NULL;
if (fde_count * sizeof(*bst) != end - p)
return NULL;
if (hdr->table_enc != (DW_EH_PE_datarel | DW_EH_PE_sdata4)) {
pr_warn_once("warning: unknown eh hdr format: %u\n",
(unsigned int)hdr->version);
return NULL;
}
bst = (struct dw_fde_table *)p;
*nr_entries = fde_count;
pr_debug("bst: %lu fde entries\n", fde_count);
return bst;
}
static long
dwarf_decode_fde_cie(struct ex_region_info *ri,
unsigned char *fde_p,
struct dw_cie *cie,
struct dw_fde *fde,
int is_eh)
{
u32 *p;
int secid;
long err;
unsigned char *cie_p;
unsigned long cie_pointer, length;
unsigned char *frame_start;
unsigned long frame_len, addr;
struct extab_info *ti;
secid = get_secid_frame(is_eh);
ti = &ri->mmap->fi.ex_sec[secid];
addr = get_ex_sec_address(ri, ti, secid);
frame_start = (unsigned char *)
ex_addr_to_mmap_addr(addr, ri, secid);
frame_len = ti->length;
pr_debug("frame: %p - %p\n",
frame_start, frame_start + frame_len);
p = (u32 *)fde_p;
length = read_mmap_data_u32(ri, p++, secid, &err);
if (err)
return err;
if (length == 0xffffffff) {
pr_warn_once("warning: 64-bit frame is not supported\n");
return -QUADD_URC_UNHANDLED_INSTRUCTION;
}
fde->offset = fde_p - frame_start;
fde->length = length + sizeof(u32);
pr_debug("FDE: fde_p: %p, offset: %#lx, len: %#lx\n",
fde_p, fde->offset, fde->length);
cie_pointer = read_mmap_data_u32(ri, p, secid, &err);
if (err)
return err;
fde->cie_pointer = cie_pointer;
cie_p = is_eh ? (unsigned char *)p - cie_pointer :
frame_start + cie_pointer;
length = read_mmap_data_u32(ri, (u32 *)cie_p,
secid, &err);
if (err)
return err;
if (length == 0xffffffff) {
pr_warn_once("warning: 64-bit frame is not supported\n");
return -QUADD_URC_UNHANDLED_INSTRUCTION;
}
cie->offset = cie_p - frame_start;
cie->length = length + sizeof(u32);
pr_debug("CIE: cie_p: %p, offset: %#lx, len: %#lx\n",
cie_p, cie->offset, cie->length);
err = decode_cie_entry(ri, cie, cie_p, cie->length, is_eh);
if (err < 0)
return err;
fde->cie = cie;
err = decode_fde_entry(ri, fde, fde_p, fde->length, is_eh);
if (err < 0)
return err;
return 0;
}
static void *
dwarf_find_fde(struct ex_region_info *ri,
struct stackframe *sf,
void *data,
unsigned long length,
unsigned long pc,
int is_eh,
struct task_struct *task)
{
long err;
int secid, secid_hdr;
const struct dw_fde_table *fi;
unsigned long fde_count = 0, data_base;
unsigned long fde_addr, init_loc;
struct dw_fde_table *bst;
struct extab_info *ti;
secid = get_secid_frame(is_eh);
secid_hdr = get_secid_frame_hdr(is_eh);
ti = &ri->mmap->fi.ex_sec[secid_hdr];
data_base = get_ex_sec_address(ri, ti, secid_hdr);
bst = dwarf_get_bs_table(ri, data, length, data_base,
&fde_count, is_eh);
if (!bst || fde_count == 0) {
pr_warn_once("warning: bs_table\n");
return NULL;
}
fi = &bst[fde_count - 1];
init_loc = dw_bst_get_initial_loc(fi, data_base);
pr_debug("pc: %#lx, last bst init_loc: %#lx", pc, init_loc);
if (pc >= init_loc) {
unsigned long start, end;
struct extab_info *ti = &ri->mmap->fi.ex_sec[secid];
fde_addr = dw_bst_get_fde_addr(fi, data_base);
fde_addr = ex_addr_to_mmap_addr(fde_addr, ri,
secid);
if (pc == init_loc)
return (void *)fde_addr;
if (ti->tf_end > 0) {
start = ti->tf_start;
end = ti->tf_end;
} else {
struct dw_cie cie;
struct dw_fde fde;
err = dwarf_decode_fde_cie(ri, (void *)fde_addr,
&cie, &fde, is_eh);
if (err < 0)
return NULL;
start = fde.initial_location;
end = start + fde.address_range;
if (sf && !sf->is_sched)
quadd_unwind_set_tail_info(ri, secid,
start, end, task);
}
pr_debug("pc: %#lx, last bst entry: %#lx - %#lx",
pc, start, end);
return (pc >= start && pc < end) ?
(void *)fde_addr : NULL;
}
fi = dwarf_bst_find_idx(data_base, bst, fde_count, pc);
if (!fi)
return NULL;
fde_addr = dw_bst_get_fde_addr(fi, data_base);
fde_addr = ex_addr_to_mmap_addr(fde_addr, ri, secid);
return (void *)fde_addr;
}
static int
__is_fde_entry_exist(struct ex_region_info *ri, unsigned long addr,
int is_eh, struct task_struct *task)
{
int secid_hdr;
unsigned char *fde_p;
struct extab_info *ti;
unsigned char *hdr_start;
unsigned long hdr_len, a;
secid_hdr = get_secid_frame_hdr(is_eh);
ti = &ri->mmap->fi.ex_sec[secid_hdr];
a = get_ex_sec_address(ri, ti, secid_hdr);
hdr_start = (unsigned char *)
ex_addr_to_mmap_addr(a, ri, secid_hdr);
hdr_len = ti->length;
fde_p = dwarf_find_fde(ri, NULL, hdr_start, hdr_len, addr, is_eh, task);
return fde_p ? 1 : 0;
}
static int
is_fde_entry_exist(struct ex_region_info *ri,
unsigned long addr,
int *is_eh,
int *is_debug,
struct task_struct *task)
{
*is_eh = 0;
*is_debug = 0;
if (is_frame_present(ri, 1)) {
if (__is_fde_entry_exist(ri, addr, 1, task))
*is_eh = 1;
}
if (is_frame_present(ri, 0)) {
if (__is_fde_entry_exist(ri, addr, 0, task))
*is_debug = 1;
}
return (*is_eh || *is_debug) ? 1 : 0;
}
static long
dwarf_decode(struct ex_region_info *ri,
struct stackframe *sf,
struct dw_cie *cie,
struct dw_fde *fde,
unsigned long pc,
int is_eh,
struct task_struct *task)
{
long err;
int secid_hdr;
unsigned char *fde_p;
unsigned char *hdr_start;
unsigned long hdr_len, addr;
struct extab_info *ti;
secid_hdr = get_secid_frame_hdr(is_eh);
ti = &ri->mmap->fi.ex_sec[secid_hdr];
addr = get_ex_sec_address(ri, ti, secid_hdr);
hdr_start = (unsigned char *)
ex_addr_to_mmap_addr(addr, ri, secid_hdr);
hdr_len = ti->length;
pr_debug("eh frame hdr: %p - %p\n",
hdr_start, hdr_start + hdr_len);
fde_p = dwarf_find_fde(ri, sf, hdr_start, hdr_len, pc, is_eh, task);
if (!fde_p)
return -QUADD_URC_IDX_NOT_FOUND;
err = dwarf_decode_fde_cie(ri, fde_p, cie, fde, is_eh);
if (err < 0)
return err;
if (pc < fde->initial_location ||
pc >= fde->initial_location + fde->address_range) {
pr_debug("pc is not in range: %#lx - %#lx\n",
fde->initial_location,
fde->initial_location + fde->address_range);
return -QUADD_URC_IDX_NOT_FOUND;
}
return 0;
}
static long def_cfa(struct stackframe *sf, struct regs_state *rs)
{
int reg = rs->cfa_register;
if (reg >= 0) {
if (reg >= QUADD_NUM_REGS)
return -QUADD_URC_TBL_IS_CORRUPT;
pr_debug("r%d --> cfa (%#lx)\n", reg, sf->cfa);
sf->cfa = sf->vregs[reg];
}
sf->cfa += rs->cfa_offset;
pr_debug("cfa += %#lx (%#lx)\n", rs->cfa_offset, sf->cfa);
return 0;
}
static long
unwind_frame(struct ex_region_info *ri,
struct stackframe *sf,
struct vm_area_struct *vma_sp,
int is_eh,
struct task_struct *task)
{
int i, num_regs;
long err;
unsigned char *insn_end;
unsigned long addr, return_addr, val, user_reg_size;
struct dw_fde fde;
struct dw_cie cie;
unsigned long pc = sf->pc;
struct regs_state *rs, *rs_initial;
int mode = sf->mode;
err = dwarf_decode(ri, sf, &cie, &fde, pc, is_eh, task);
if (err < 0)
return err;
sf->pc = fde.initial_location;
rs = &sf->rs;
rs_initial = &sf->rs_initial;
rs->cfa_register = -1;
rs_initial->cfa_register = -1;
rules_cleanup(rs, mode);
if (cie.initial_insn) {
insn_end = cie.initial_insn + cie.initial_insn_len;
err = dwarf_cfa_exec_insns(ri, cie.initial_insn,
insn_end, &cie, sf, pc, is_eh);
if (err)
return err;
}
memcpy(rs_initial, rs, sizeof(*rs));
if (fde.instructions) {
insn_end = fde.instructions + fde.insn_length;
err = dwarf_cfa_exec_insns(ri, fde.instructions,
insn_end, fde.cie, sf, pc, is_eh);
if (err)
return err;
}
pr_debug("mode: %s\n", (mode == DW_MODE_ARM32) ? "arm32" : "arm64");
pr_debug("initial cfa: %#lx\n", sf->cfa);
user_reg_size = get_user_reg_size(mode);
err = def_cfa(sf, rs);
if (err < 0)
return err;
pr_debug("pc: %#lx, exec pc: %#lx, lr: %#lx\n",
pc, sf->pc, sf->vregs[regnum_lr(mode)]);
pr_debug("sp: %#lx, fp: %#lx, fp_thumb: %#lx\n",
sf->vregs[regnum_sp(mode)],
sf->vregs[regnum_fp(mode)],
sf->vregs[ARM32_FP_THUMB]);
pr_debug("lr rule: %#lx/%ld (where: %u)\n",
rs->reg[regnum_lr(mode)].loc.reg,
rs->reg[regnum_lr(mode)].loc.offset,
rs->reg[regnum_lr(mode)].where);
pr_debug("fp rule: %#lx/%ld (where: %u)\n",
rs->reg[regnum_fp(mode)].loc.reg,
rs->reg[regnum_fp(mode)].loc.offset,
rs->reg[regnum_fp(mode)].where);
pr_debug("fp_thumb rule: %#lx/%ld (where: %u)\n",
rs->reg[ARM32_FP_THUMB].loc.reg,
rs->reg[ARM32_FP_THUMB].loc.offset,
rs->reg[ARM32_FP_THUMB].where);
pr_debug("cfa_offset: %ld (%#lx)\n",
rs->cfa_offset, rs->cfa_offset);
pr_debug("cfa_register: %u\n", rs->cfa_register);
pr_debug("new cfa: %#lx\n", sf->cfa);
num_regs = (mode == DW_MODE_ARM32) ?
QUADD_AARCH32_REGISTERS :
QUADD_AARCH64_REGISTERS;
for (i = 0; i < num_regs; i++) {
switch (rs->reg[i].where) {
case DW_WHERE_UNDEF:
break;
case DW_WHERE_SAME:
break;
case DW_WHERE_CFAREL:
addr = sf->cfa + rs->reg[i].loc.offset;
if (!validate_stack_addr(addr, vma_sp, user_reg_size,
mode != DW_MODE_ARM32))
return -QUADD_URC_SP_INCORRECT;
if (mode == DW_MODE_ARM32) {
u32 val32;
err = read_user_data(&val32,
(void __user *)addr,
sizeof(u32));
val = val32;
} else {
err = read_user_data(&val, (void __user *)addr,
sizeof(unsigned long));
}
if (err < 0)
return err;
sf->vregs[i] = val;
pr_debug("[r%d] DW_WHERE_CFAREL: new val: %#lx\n",
i, val);
break;
default:
pr_err_once("[r%d] error: unsupported rule (%d)\n",
i, rs->reg[i].where);
break;
}
}
return_addr = sf->vregs[regnum_lr(mode)];
pr_debug("return_addr: %#lx\n", return_addr);
if (!validate_pc_addr(return_addr, user_reg_size))
return -QUADD_URC_PC_INCORRECT;
sf->pc = return_addr;
sf->vregs[regnum_sp(mode)] = sf->cfa;
return 0;
}
static void
unwind_backtrace(struct quadd_callchain *cc,
struct ex_region_info *ri,
struct stackframe *sf,
struct vm_area_struct *vma_sp,
struct task_struct *task)
{
unsigned long user_reg_size;
struct ex_region_info ri_new, *prev_ri = NULL;
unsigned int unw_type;
int is_eh = 1, mode = sf->mode;
cc->urc_dwarf = QUADD_URC_FAILURE;
user_reg_size = get_user_reg_size(mode);
while (1) {
long sp, err;
int nr_added, is_stack_ok;
int __is_eh, __is_debug;
struct vm_area_struct *vma_pc;
unsigned long addr, where = sf->pc;
struct mm_struct *mm = task->mm;
if (!mm)
break;
sp = sf->vregs[regnum_sp(mode)];
if (!validate_stack_addr(sp, vma_sp, user_reg_size,
cc->cs_64)) {
cc->urc_dwarf = QUADD_URC_SP_INCORRECT;
break;
}
vma_pc = find_vma(mm, sf->pc);
if (!vma_pc)
break;
addr = ri->vm_start;
if (!is_vma_addr(addr, vma_pc, user_reg_size)) {
if (prev_ri) {
quadd_put_dw_frames(prev_ri);
prev_ri = NULL;
}
err = quadd_get_dw_frames(vma_pc->vm_start,
&ri_new, task);
if (err) {
cc->urc_dwarf = QUADD_URC_TBL_NOT_EXIST;
break;
}
pr_debug("ri: %#lx ---> %#lx\n",
ri->vm_start, ri_new.vm_start);
prev_ri = ri = &ri_new;
}
if (!is_fde_entry_exist(ri, sf->pc, &__is_eh,
&__is_debug, task)) {
pr_debug("eh/debug fde entries are not existed\n");
cc->urc_dwarf = QUADD_URC_IDX_NOT_FOUND;
break;
}
pr_debug("is_eh: %d, is_debug: %d\n", __is_eh, __is_debug);
if (is_eh) {
if (!__is_eh)
is_eh = 0;
} else {
if (!__is_debug)
is_eh = 1;
}
err = unwind_frame(ri, sf, vma_sp, is_eh, task);
if (err < 0) {
if (__is_eh && __is_debug) {
is_eh ^= 1;
err = unwind_frame(ri, sf, vma_sp, is_eh, task);
if (err < 0) {
cc->urc_dwarf = -err;
break;
}
} else {
cc->urc_dwarf = -err;
break;
}
}
unw_type = is_eh ? QUADD_UNW_TYPE_DWARF_EH :
QUADD_UNW_TYPE_DWARF_DF;
pr_debug("[%s]: function at [<%08lx>] from [<%08lx>]\n",
is_eh ? "eh" : "debug", where, sf->pc);
cc->curr_sp = sf->vregs[regnum_sp(mode)];
cc->curr_fp = sf->vregs[regnum_fp(mode)];
if (mode == DW_MODE_ARM32)
cc->curr_fp_thumb = sf->vregs[ARM32_FP_THUMB];
cc->curr_pc = sf->pc;
cc->curr_lr = sf->vregs[regnum_lr(mode)];
is_stack_ok = cc->nr > 0 ?
cc->curr_sp > sp : cc->curr_sp >= sp;
if (!is_stack_ok) {
cc->urc_dwarf = QUADD_URC_SP_INCORRECT;
break;
}
nr_added = quadd_callchain_store(cc, sf->pc, unw_type);
if (nr_added == 0)
break;
}
if (prev_ri)
quadd_put_dw_frames(prev_ri);
}
int
quadd_is_ex_entry_exist_dwarf(struct quadd_event_context *event_ctx,
unsigned long addr)
{
long err;
int is_eh, is_debug, res;
struct ex_region_info ri;
struct vm_area_struct *vma;
struct pt_regs *regs = event_ctx->regs;
struct task_struct *task = event_ctx->task;
struct mm_struct *mm = task->mm;
if (!regs || !mm)
return 0;
vma = find_vma(mm, addr);
if (!vma)
return 0;
err = quadd_get_dw_frames(vma->vm_start, &ri, task);
if (err)
return 0;
res = is_fde_entry_exist(&ri, addr, &is_eh, &is_debug, task);
quadd_put_dw_frames(&ri);
return res;
}
unsigned int
quadd_get_user_cc_dwarf(struct quadd_event_context *event_ctx,
struct quadd_callchain *cc)
{
long err;
int mode, nr_prev = cc->nr;
unsigned long ip, lr, sp, fp, fp_thumb;
struct vm_area_struct *vma, *vma_sp;
struct ex_region_info ri;
struct stackframe *sf;
struct pt_regs *regs = event_ctx->regs;
struct task_struct *task = event_ctx->task;
struct mm_struct *mm = task->mm;
struct dwarf_cpu_context *cpu_ctx = this_cpu_ptr(ctx.cpu_ctx);
if (!regs || !mm)
return 0;
if (cc->urc_dwarf == QUADD_URC_LEVEL_TOO_DEEP)
return nr_prev;
cc->urc_dwarf = QUADD_URC_FAILURE;
if (cc->curr_sp) {
ip = cc->curr_pc;
sp = cc->curr_sp;
fp = cc->curr_fp;
fp_thumb = cc->curr_fp_thumb;
lr = cc->curr_lr;
} else {
ip = instruction_pointer(regs);
lr = quadd_user_link_register(regs);
sp = quadd_user_stack_pointer(regs);
#ifdef CONFIG_ARM64
if (compat_user_mode(regs)) {
fp = regs->compat_usr(ARM32_FP);
fp_thumb = regs->compat_usr(ARM32_FP_THUMB);
} else {
fp = regs->regs[ARM64_FP];
fp_thumb = 0;
}
#else
fp = regs->ARM_fp;
fp_thumb = regs->ARM_r7;
#endif
}
#ifdef CONFIG_ARM64
mode = compat_user_mode(regs) ?
DW_MODE_ARM32 : DW_MODE_ARM64;
#else
mode = DW_MODE_ARM32;
#endif
pr_debug("%s: pid: %u, pc: %#lx, lr: %#lx\n",
__func__, task_tgid_nr(task), ip, lr);
pr_debug("%s: pid: %u, sp: %#lx, fp: %#lx, fp_thumb: %#lx\n",
__func__, task_tgid_nr(task), sp, fp, fp_thumb);
sf = &cpu_ctx->sf;
sf->vregs[regnum_lr(mode)] = lr;
sf->pc = ip;
sf->vregs[regnum_sp(mode)] = sp;
sf->vregs[regnum_fp(mode)] = fp;
if (mode == DW_MODE_ARM32)
sf->vregs[ARM32_FP_THUMB] = fp_thumb;
cpu_ctx->dw_ptr_size = (mode == DW_MODE_ARM32) ?
sizeof(u32) : sizeof(u64);
sf->mode = mode;
sf->is_sched = event_ctx->is_sched;
sf->cfa = 0;
vma = find_vma(mm, ip);
if (!vma)
return 0;
vma_sp = find_vma(mm, sp);
if (!vma_sp)
return 0;
err = quadd_get_dw_frames(vma->vm_start, &ri, task);
if (err) {
cc->urc_dwarf = QUADD_URC_TBL_NOT_EXIST;
return 0;
}
unwind_backtrace(cc, &ri, sf, vma_sp, task);
quadd_put_dw_frames(&ri);
pr_debug("%s: pid: %u: mode: %s, cc->nr: %d --> %d\n",
__func__, task_tgid_nr(task),
(mode == DW_MODE_ARM32) ? "arm32" : "arm64",
nr_prev, cc->nr);
return cc->nr;
}
int quadd_dwarf_unwind_start(void)
{
if (!atomic_cmpxchg(&ctx.started, 0, 1)) {
ctx.cpu_ctx = alloc_percpu(struct dwarf_cpu_context);
if (!ctx.cpu_ctx) {
atomic_set(&ctx.started, 0);
return -ENOMEM;
}
}
return 0;
}
void quadd_dwarf_unwind_stop(void)
{
if (atomic_cmpxchg(&ctx.started, 1, 0))
free_percpu(ctx.cpu_ctx);
}
int quadd_dwarf_unwind_init(void)
{
atomic_set(&ctx.started, 0);
return 0;
}