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-rw-r--r--arch/loongarch/kernel/Makefile2
-rw-r--r--arch/loongarch/kernel/alternative.c6
-rw-r--r--arch/loongarch/kernel/cpu-probe.c2
-rw-r--r--arch/loongarch/kernel/genex.S3
-rw-r--r--arch/loongarch/kernel/inst.c45
-rw-r--r--arch/loongarch/kernel/process.c12
-rw-r--r--arch/loongarch/kernel/traps.c3
-rw-r--r--arch/loongarch/kernel/unwind.c32
-rw-r--r--arch/loongarch/kernel/unwind_guess.c49
-rw-r--r--arch/loongarch/kernel/unwind_prologue.c252
10 files changed, 205 insertions, 201 deletions
diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile
index fcaa024a685e..c8cfbd562921 100644
--- a/arch/loongarch/kernel/Makefile
+++ b/arch/loongarch/kernel/Makefile
@@ -8,7 +8,7 @@ extra-y := vmlinux.lds
obj-y += head.o cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \
traps.o irq.o idle.o process.o dma.o mem.o io.o reset.o switch.o \
elf.o syscall.o signal.o time.o topology.o inst.o ptrace.o vdso.o \
- alternative.o unaligned.o
+ alternative.o unaligned.o unwind.o
obj-$(CONFIG_ACPI) += acpi.o
obj-$(CONFIG_EFI) += efi.o
diff --git a/arch/loongarch/kernel/alternative.c b/arch/loongarch/kernel/alternative.c
index c5aebeac960b..4ad13847e962 100644
--- a/arch/loongarch/kernel/alternative.c
+++ b/arch/loongarch/kernel/alternative.c
@@ -74,7 +74,7 @@ static void __init_or_module recompute_jump(union loongarch_instruction *buf,
switch (src->reg0i26_format.opcode) {
case b_op:
case bl_op:
- jump_addr = cur_pc + sign_extend((si_h << 16 | si_l) << 2, 27);
+ jump_addr = cur_pc + sign_extend64((si_h << 16 | si_l) << 2, 27);
if (in_alt_jump(jump_addr, start, end))
return;
offset = jump_addr - pc;
@@ -93,7 +93,7 @@ static void __init_or_module recompute_jump(union loongarch_instruction *buf,
fallthrough;
case beqz_op:
case bnez_op:
- jump_addr = cur_pc + sign_extend((si_h << 16 | si_l) << 2, 22);
+ jump_addr = cur_pc + sign_extend64((si_h << 16 | si_l) << 2, 22);
if (in_alt_jump(jump_addr, start, end))
return;
offset = jump_addr - pc;
@@ -112,7 +112,7 @@ static void __init_or_module recompute_jump(union loongarch_instruction *buf,
case bge_op:
case bltu_op:
case bgeu_op:
- jump_addr = cur_pc + sign_extend(si << 2, 17);
+ jump_addr = cur_pc + sign_extend64(si << 2, 17);
if (in_alt_jump(jump_addr, start, end))
return;
offset = jump_addr - pc;
diff --git a/arch/loongarch/kernel/cpu-probe.c b/arch/loongarch/kernel/cpu-probe.c
index 255a09876ef2..3a3fce2d7846 100644
--- a/arch/loongarch/kernel/cpu-probe.c
+++ b/arch/loongarch/kernel/cpu-probe.c
@@ -94,7 +94,7 @@ static void cpu_probe_common(struct cpuinfo_loongarch *c)
c->options = LOONGARCH_CPU_CPUCFG | LOONGARCH_CPU_CSR |
LOONGARCH_CPU_TLB | LOONGARCH_CPU_VINT | LOONGARCH_CPU_WATCH;
- elf_hwcap |= HWCAP_LOONGARCH_CRC32;
+ elf_hwcap = HWCAP_LOONGARCH_CPUCFG | HWCAP_LOONGARCH_CRC32;
config = read_cpucfg(LOONGARCH_CPUCFG1);
if (config & CPUCFG1_UAL) {
diff --git a/arch/loongarch/kernel/genex.S b/arch/loongarch/kernel/genex.S
index 75e5be807a0d..7e5c293ed89f 100644
--- a/arch/loongarch/kernel/genex.S
+++ b/arch/loongarch/kernel/genex.S
@@ -67,14 +67,17 @@ SYM_FUNC_END(except_vec_cex)
.macro BUILD_HANDLER exception handler prep
.align 5
SYM_FUNC_START(handle_\exception)
+ 666:
BACKUP_T0T1
SAVE_ALL
build_prep_\prep
move a0, sp
la.abs t0, do_\handler
jirl ra, t0, 0
+ 668:
RESTORE_ALL_AND_RET
SYM_FUNC_END(handle_\exception)
+ SYM_DATA(unwind_hint_\exception, .word 668b - 666b)
.endm
BUILD_HANDLER ade ade badv
diff --git a/arch/loongarch/kernel/inst.c b/arch/loongarch/kernel/inst.c
index 512579d79b22..badc59087042 100644
--- a/arch/loongarch/kernel/inst.c
+++ b/arch/loongarch/kernel/inst.c
@@ -58,7 +58,6 @@ u32 larch_insn_gen_nop(void)
u32 larch_insn_gen_b(unsigned long pc, unsigned long dest)
{
long offset = dest - pc;
- unsigned int immediate_l, immediate_h;
union loongarch_instruction insn;
if ((offset & 3) || offset < -SZ_128M || offset >= SZ_128M) {
@@ -66,15 +65,7 @@ u32 larch_insn_gen_b(unsigned long pc, unsigned long dest)
return INSN_BREAK;
}
- offset >>= 2;
-
- immediate_l = offset & 0xffff;
- offset >>= 16;
- immediate_h = offset & 0x3ff;
-
- insn.reg0i26_format.opcode = b_op;
- insn.reg0i26_format.immediate_l = immediate_l;
- insn.reg0i26_format.immediate_h = immediate_h;
+ emit_b(&insn, offset >> 2);
return insn.word;
}
@@ -82,7 +73,6 @@ u32 larch_insn_gen_b(unsigned long pc, unsigned long dest)
u32 larch_insn_gen_bl(unsigned long pc, unsigned long dest)
{
long offset = dest - pc;
- unsigned int immediate_l, immediate_h;
union loongarch_instruction insn;
if ((offset & 3) || offset < -SZ_128M || offset >= SZ_128M) {
@@ -90,15 +80,7 @@ u32 larch_insn_gen_bl(unsigned long pc, unsigned long dest)
return INSN_BREAK;
}
- offset >>= 2;
-
- immediate_l = offset & 0xffff;
- offset >>= 16;
- immediate_h = offset & 0x3ff;
-
- insn.reg0i26_format.opcode = bl_op;
- insn.reg0i26_format.immediate_l = immediate_l;
- insn.reg0i26_format.immediate_h = immediate_h;
+ emit_bl(&insn, offset >> 2);
return insn.word;
}
@@ -107,10 +89,7 @@ u32 larch_insn_gen_or(enum loongarch_gpr rd, enum loongarch_gpr rj, enum loongar
{
union loongarch_instruction insn;
- insn.reg3_format.opcode = or_op;
- insn.reg3_format.rd = rd;
- insn.reg3_format.rj = rj;
- insn.reg3_format.rk = rk;
+ emit_or(&insn, rd, rj, rk);
return insn.word;
}
@@ -124,9 +103,7 @@ u32 larch_insn_gen_lu12iw(enum loongarch_gpr rd, int imm)
{
union loongarch_instruction insn;
- insn.reg1i20_format.opcode = lu12iw_op;
- insn.reg1i20_format.rd = rd;
- insn.reg1i20_format.immediate = imm;
+ emit_lu12iw(&insn, rd, imm);
return insn.word;
}
@@ -135,9 +112,7 @@ u32 larch_insn_gen_lu32id(enum loongarch_gpr rd, int imm)
{
union loongarch_instruction insn;
- insn.reg1i20_format.opcode = lu32id_op;
- insn.reg1i20_format.rd = rd;
- insn.reg1i20_format.immediate = imm;
+ emit_lu32id(&insn, rd, imm);
return insn.word;
}
@@ -146,10 +121,7 @@ u32 larch_insn_gen_lu52id(enum loongarch_gpr rd, enum loongarch_gpr rj, int imm)
{
union loongarch_instruction insn;
- insn.reg2i12_format.opcode = lu52id_op;
- insn.reg2i12_format.rd = rd;
- insn.reg2i12_format.rj = rj;
- insn.reg2i12_format.immediate = imm;
+ emit_lu52id(&insn, rd, rj, imm);
return insn.word;
}
@@ -158,10 +130,7 @@ u32 larch_insn_gen_jirl(enum loongarch_gpr rd, enum loongarch_gpr rj, unsigned l
{
union loongarch_instruction insn;
- insn.reg2i16_format.opcode = jirl_op;
- insn.reg2i16_format.rd = rd;
- insn.reg2i16_format.rj = rj;
- insn.reg2i16_format.immediate = (dest - pc) >> 2;
+ emit_jirl(&insn, rj, rd, (dest - pc) >> 2);
return insn.word;
}
diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c
index c583b1ef1f44..edfd220a3737 100644
--- a/arch/loongarch/kernel/process.c
+++ b/arch/loongarch/kernel/process.c
@@ -191,20 +191,14 @@ out:
unsigned long __get_wchan(struct task_struct *task)
{
- unsigned long pc;
+ unsigned long pc = 0;
struct unwind_state state;
if (!try_get_task_stack(task))
return 0;
- unwind_start(&state, task, NULL);
- state.sp = thread_saved_fp(task);
- get_stack_info(state.sp, state.task, &state.stack_info);
- state.pc = thread_saved_ra(task);
-#ifdef CONFIG_UNWINDER_PROLOGUE
- state.type = UNWINDER_PROLOGUE;
-#endif
- for (; !unwind_done(&state); unwind_next_frame(&state)) {
+ for (unwind_start(&state, task, NULL);
+ !unwind_done(&state); unwind_next_frame(&state)) {
pc = unwind_get_return_address(&state);
if (!pc)
break;
diff --git a/arch/loongarch/kernel/traps.c b/arch/loongarch/kernel/traps.c
index 7ea62faeeadb..c38a146a973b 100644
--- a/arch/loongarch/kernel/traps.c
+++ b/arch/loongarch/kernel/traps.c
@@ -72,9 +72,6 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs,
if (!task)
task = current;
- if (user_mode(regs))
- state.type = UNWINDER_GUESS;
-
printk("%sCall Trace:", loglvl);
for (unwind_start(&state, task, pregs);
!unwind_done(&state); unwind_next_frame(&state)) {
diff --git a/arch/loongarch/kernel/unwind.c b/arch/loongarch/kernel/unwind.c
new file mode 100644
index 000000000000..a463d6961344
--- /dev/null
+++ b/arch/loongarch/kernel/unwind.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
+ */
+#include <linux/kernel.h>
+#include <linux/ftrace.h>
+
+#include <asm/unwind.h>
+
+bool default_next_frame(struct unwind_state *state)
+{
+ struct stack_info *info = &state->stack_info;
+ unsigned long addr;
+
+ if (unwind_done(state))
+ return false;
+
+ do {
+ for (state->sp += sizeof(unsigned long);
+ state->sp < info->end; state->sp += sizeof(unsigned long)) {
+ addr = *(unsigned long *)(state->sp);
+ state->pc = unwind_graph_addr(state, addr, state->sp + 8);
+ if (__kernel_text_address(state->pc))
+ return true;
+ }
+
+ state->sp = info->next_sp;
+
+ } while (!get_stack_info(state->sp, state->task, info));
+
+ return false;
+}
diff --git a/arch/loongarch/kernel/unwind_guess.c b/arch/loongarch/kernel/unwind_guess.c
index e2d2e4f3001f..98379b7d4147 100644
--- a/arch/loongarch/kernel/unwind_guess.c
+++ b/arch/loongarch/kernel/unwind_guess.c
@@ -2,37 +2,18 @@
/*
* Copyright (C) 2022 Loongson Technology Corporation Limited
*/
-#include <linux/kernel.h>
-#include <linux/ftrace.h>
-
#include <asm/unwind.h>
unsigned long unwind_get_return_address(struct unwind_state *state)
{
- if (unwind_done(state))
- return 0;
- else if (state->first)
- return state->pc;
-
- return *(unsigned long *)(state->sp);
+ return __unwind_get_return_address(state);
}
EXPORT_SYMBOL_GPL(unwind_get_return_address);
void unwind_start(struct unwind_state *state, struct task_struct *task,
struct pt_regs *regs)
{
- memset(state, 0, sizeof(*state));
-
- if (regs) {
- state->sp = regs->regs[3];
- state->pc = regs->csr_era;
- }
-
- state->task = task;
- state->first = true;
-
- get_stack_info(state->sp, state->task, &state->stack_info);
-
+ __unwind_start(state, task, regs);
if (!unwind_done(state) && !__kernel_text_address(state->pc))
unwind_next_frame(state);
}
@@ -40,30 +21,6 @@ EXPORT_SYMBOL_GPL(unwind_start);
bool unwind_next_frame(struct unwind_state *state)
{
- struct stack_info *info = &state->stack_info;
- unsigned long addr;
-
- if (unwind_done(state))
- return false;
-
- if (state->first)
- state->first = false;
-
- do {
- for (state->sp += sizeof(unsigned long);
- state->sp < info->end;
- state->sp += sizeof(unsigned long)) {
- addr = *(unsigned long *)(state->sp);
- state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
- addr, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
- if (__kernel_text_address(addr))
- return true;
- }
-
- state->sp = info->next_sp;
-
- } while (!get_stack_info(state->sp, state->task, info));
-
- return false;
+ return default_next_frame(state);
}
EXPORT_SYMBOL_GPL(unwind_next_frame);
diff --git a/arch/loongarch/kernel/unwind_prologue.c b/arch/loongarch/kernel/unwind_prologue.c
index 0f8d1451ebb8..9095fde8e55d 100644
--- a/arch/loongarch/kernel/unwind_prologue.c
+++ b/arch/loongarch/kernel/unwind_prologue.c
@@ -2,61 +2,116 @@
/*
* Copyright (C) 2022 Loongson Technology Corporation Limited
*/
+#include <linux/cpumask.h>
#include <linux/ftrace.h>
#include <linux/kallsyms.h>
#include <asm/inst.h>
+#include <asm/loongson.h>
#include <asm/ptrace.h>
+#include <asm/setup.h>
#include <asm/unwind.h>
-static inline void unwind_state_fixup(struct unwind_state *state)
-{
-#ifdef CONFIG_DYNAMIC_FTRACE
- static unsigned long ftrace = (unsigned long)ftrace_call + 4;
-
- if (state->pc == ftrace)
- state->is_ftrace = true;
+extern const int unwind_hint_ade;
+extern const int unwind_hint_ale;
+extern const int unwind_hint_bp;
+extern const int unwind_hint_fpe;
+extern const int unwind_hint_fpu;
+extern const int unwind_hint_lsx;
+extern const int unwind_hint_lasx;
+extern const int unwind_hint_lbt;
+extern const int unwind_hint_ri;
+extern const int unwind_hint_watch;
+extern unsigned long eentry;
+#ifdef CONFIG_NUMA
+extern unsigned long pcpu_handlers[NR_CPUS];
#endif
-}
-unsigned long unwind_get_return_address(struct unwind_state *state)
+static inline bool scan_handlers(unsigned long entry_offset)
{
+ int idx, offset;
- if (unwind_done(state))
- return 0;
- else if (state->type)
- return state->pc;
- else if (state->first)
- return state->pc;
-
- return *(unsigned long *)(state->sp);
+ if (entry_offset >= EXCCODE_INT_START * VECSIZE)
+ return false;
+ idx = entry_offset / VECSIZE;
+ offset = entry_offset % VECSIZE;
+ switch (idx) {
+ case EXCCODE_ADE:
+ return offset == unwind_hint_ade;
+ case EXCCODE_ALE:
+ return offset == unwind_hint_ale;
+ case EXCCODE_BP:
+ return offset == unwind_hint_bp;
+ case EXCCODE_FPE:
+ return offset == unwind_hint_fpe;
+ case EXCCODE_FPDIS:
+ return offset == unwind_hint_fpu;
+ case EXCCODE_LSXDIS:
+ return offset == unwind_hint_lsx;
+ case EXCCODE_LASXDIS:
+ return offset == unwind_hint_lasx;
+ case EXCCODE_BTDIS:
+ return offset == unwind_hint_lbt;
+ case EXCCODE_INE:
+ return offset == unwind_hint_ri;
+ case EXCCODE_WATCH:
+ return offset == unwind_hint_watch;
+ default:
+ return false;
+ }
}
-EXPORT_SYMBOL_GPL(unwind_get_return_address);
-static bool unwind_by_guess(struct unwind_state *state)
+static inline bool fix_exception(unsigned long pc)
{
- struct stack_info *info = &state->stack_info;
- unsigned long addr;
-
- for (state->sp += sizeof(unsigned long);
- state->sp < info->end;
- state->sp += sizeof(unsigned long)) {
- addr = *(unsigned long *)(state->sp);
- state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
- addr, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
- if (__kernel_text_address(addr))
+#ifdef CONFIG_NUMA
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ if (!pcpu_handlers[cpu])
+ continue;
+ if (scan_handlers(pc - pcpu_handlers[cpu]))
return true;
}
+#endif
+ return scan_handlers(pc - eentry);
+}
+/*
+ * As we meet ftrace_regs_entry, reset first flag like first doing
+ * tracing. Prologue analysis will stop soon because PC is at entry.
+ */
+static inline bool fix_ftrace(unsigned long pc)
+{
+#ifdef CONFIG_DYNAMIC_FTRACE
+ return pc == (unsigned long)ftrace_call + LOONGARCH_INSN_SIZE;
+#else
return false;
+#endif
}
+static inline bool unwind_state_fixup(struct unwind_state *state)
+{
+ if (!fix_exception(state->pc) && !fix_ftrace(state->pc))
+ return false;
+
+ state->reset = true;
+ return true;
+}
+
+/*
+ * LoongArch function prologue is like follows,
+ * [instructions not use stack var]
+ * addi.d sp, sp, -imm
+ * st.d xx, sp, offset <- save callee saved regs and
+ * st.d yy, sp, offset save ra if function is nest.
+ * [others instructions]
+ */
static bool unwind_by_prologue(struct unwind_state *state)
{
long frame_ra = -1;
unsigned long frame_size = 0;
- unsigned long size, offset, pc = state->pc;
+ unsigned long size, offset, pc;
struct pt_regs *regs;
struct stack_info *info = &state->stack_info;
union loongarch_instruction *ip, *ip_end;
@@ -64,20 +119,21 @@ static bool unwind_by_prologue(struct unwind_state *state)
if (state->sp >= info->end || state->sp < info->begin)
return false;
- if (state->is_ftrace) {
- /*
- * As we meet ftrace_regs_entry, reset first flag like first doing
- * tracing. Prologue analysis will stop soon because PC is at entry.
- */
+ if (state->reset) {
regs = (struct pt_regs *)state->sp;
state->first = true;
- state->is_ftrace = false;
+ state->reset = false;
state->pc = regs->csr_era;
state->ra = regs->regs[1];
state->sp = regs->regs[3];
return true;
}
+ /*
+ * When first is not set, the PC is a return address in the previous frame.
+ * We need to adjust its value in case overflow to the next symbol.
+ */
+ pc = state->pc - (state->first ? 0 : LOONGARCH_INSN_SIZE);
if (!kallsyms_lookup_size_offset(pc, &size, &offset))
return false;
@@ -93,6 +149,10 @@ static bool unwind_by_prologue(struct unwind_state *state)
ip++;
}
+ /*
+ * Can't find stack alloc action, PC may be in a leaf function. Only the
+ * first being true is reasonable, otherwise indicate analysis is broken.
+ */
if (!frame_size) {
if (state->first)
goto first;
@@ -110,6 +170,7 @@ static bool unwind_by_prologue(struct unwind_state *state)
ip++;
}
+ /* Can't find save $ra action, PC may be in a leaf function, too. */
if (frame_ra < 0) {
if (state->first) {
state->sp = state->sp + frame_size;
@@ -118,88 +179,47 @@ static bool unwind_by_prologue(struct unwind_state *state)
return false;
}
- if (state->first)
- state->first = false;
-
state->pc = *(unsigned long *)(state->sp + frame_ra);
state->sp = state->sp + frame_size;
goto out;
first:
- state->first = false;
- if (state->pc == state->ra)
- return false;
-
state->pc = state->ra;
out:
- unwind_state_fixup(state);
- return !!__kernel_text_address(state->pc);
-}
-
-void unwind_start(struct unwind_state *state, struct task_struct *task,
- struct pt_regs *regs)
-{
- memset(state, 0, sizeof(*state));
-
- if (regs && __kernel_text_address(regs->csr_era)) {
- state->pc = regs->csr_era;
- state->sp = regs->regs[3];
- state->ra = regs->regs[1];
- state->type = UNWINDER_PROLOGUE;
- }
-
- state->task = task;
- state->first = true;
-
- get_stack_info(state->sp, state->task, &state->stack_info);
-
- if (!unwind_done(state) && !__kernel_text_address(state->pc))
- unwind_next_frame(state);
+ state->first = false;
+ return unwind_state_fixup(state) || __kernel_text_address(state->pc);
}
-EXPORT_SYMBOL_GPL(unwind_start);
-bool unwind_next_frame(struct unwind_state *state)
+static bool next_frame(struct unwind_state *state)
{
- struct stack_info *info = &state->stack_info;
- struct pt_regs *regs;
unsigned long pc;
+ struct pt_regs *regs;
+ struct stack_info *info = &state->stack_info;
if (unwind_done(state))
return false;
do {
- switch (state->type) {
- case UNWINDER_GUESS:
- state->first = false;
- if (unwind_by_guess(state))
- return true;
- break;
+ if (unwind_by_prologue(state)) {
+ state->pc = unwind_graph_addr(state, state->pc, state->sp);
+ return true;
+ }
+
+ if (info->type == STACK_TYPE_IRQ && info->end == state->sp) {
+ regs = (struct pt_regs *)info->next_sp;
+ pc = regs->csr_era;
+
+ if (user_mode(regs) || !__kernel_text_address(pc))
+ return false;
+
+ state->first = true;
+ state->pc = pc;
+ state->ra = regs->regs[1];
+ state->sp = regs->regs[3];
+ get_stack_info(state->sp, state->task, info);
- case UNWINDER_PROLOGUE:
- if (unwind_by_prologue(state)) {
- state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
- state->pc, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
- return true;
- }
-
- if (info->type == STACK_TYPE_IRQ &&
- info->end == state->sp) {
- regs = (struct pt_regs *)info->next_sp;
- pc = regs->csr_era;
-
- if (user_mode(regs) || !__kernel_text_address(pc))
- return false;
-
- state->first = true;
- state->ra = regs->regs[1];
- state->sp = regs->regs[3];
- state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
- pc, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
- get_stack_info(state->sp, state->task, info);
-
- return true;
- }
+ return true;
}
state->sp = info->next_sp;
@@ -208,4 +228,36 @@ bool unwind_next_frame(struct unwind_state *state)
return false;
}
+
+unsigned long unwind_get_return_address(struct unwind_state *state)
+{
+ return __unwind_get_return_address(state);
+}
+EXPORT_SYMBOL_GPL(unwind_get_return_address);
+
+void unwind_start(struct unwind_state *state, struct task_struct *task,
+ struct pt_regs *regs)
+{
+ __unwind_start(state, task, regs);
+ state->type = UNWINDER_PROLOGUE;
+ state->first = true;
+
+ /*
+ * The current PC is not kernel text address, we cannot find its
+ * relative symbol. Thus, prologue analysis will be broken. Luckily,
+ * we can use the default_next_frame().
+ */
+ if (!__kernel_text_address(state->pc)) {
+ state->type = UNWINDER_GUESS;
+ if (!unwind_done(state))
+ unwind_next_frame(state);
+ }
+}
+EXPORT_SYMBOL_GPL(unwind_start);
+
+bool unwind_next_frame(struct unwind_state *state)
+{
+ return state->type == UNWINDER_PROLOGUE ?
+ next_frame(state) : default_next_frame(state);
+}
EXPORT_SYMBOL_GPL(unwind_next_frame);