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Diffstat (limited to 'arch/arm64/kernel/traps.c')
-rw-r--r--arch/arm64/kernel/traps.c120
1 files changed, 99 insertions, 21 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 9119722eb347..d242a46e8957 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -33,11 +33,13 @@
#include <linux/syscalls.h>
#include <asm/atomic.h>
+#include <asm/barrier.h>
#include <asm/bug.h>
#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/insn.h>
#include <asm/traps.h>
+#include <asm/stack_pointer.h>
#include <asm/stacktrace.h>
#include <asm/exception.h>
#include <asm/system_misc.h>
@@ -146,17 +148,32 @@ static void dump_instr(const char *lvl, struct pt_regs *regs)
static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
{
struct stackframe frame;
+ unsigned long irq_stack_ptr;
+ int skip;
pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
if (!tsk)
tsk = current;
- if (regs) {
- frame.fp = regs->regs[29];
- frame.sp = regs->sp;
- frame.pc = regs->pc;
- } else if (tsk == current) {
+ if (!try_get_task_stack(tsk))
+ return;
+
+ /*
+ * Switching between stacks is valid when tracing current and in
+ * non-preemptible context.
+ */
+ if (tsk == current && !preemptible())
+ irq_stack_ptr = IRQ_STACK_PTR(smp_processor_id());
+ else
+ irq_stack_ptr = 0;
+
+ pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
+
+ if (!tsk)
+ tsk = current;
+
+ if (tsk == current) {
frame.fp = (unsigned long)__builtin_frame_address(0);
frame.sp = current_stack_pointer;
frame.pc = (unsigned long)dump_backtrace;
@@ -168,22 +185,52 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
frame.sp = thread_saved_sp(tsk);
frame.pc = thread_saved_pc(tsk);
}
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ frame.graph = tsk->curr_ret_stack;
+#endif
- pr_emerg("Call trace:\n");
+ skip = !!regs;
+ printk("Call trace:\n");
while (1) {
unsigned long where = frame.pc;
unsigned long stack;
int ret;
- dump_backtrace_entry(where);
- ret = unwind_frame(&frame);
+ /* skip until specified stack frame */
+ if (!skip) {
+ dump_backtrace_entry(where);
+ } else if (frame.fp == regs->regs[29]) {
+ skip = 0;
+ /*
+ * Mostly, this is the case where this function is
+ * called in panic/abort. As exception handler's
+ * stack frame does not contain the corresponding pc
+ * at which an exception has taken place, use regs->pc
+ * instead.
+ */
+ dump_backtrace_entry(regs->pc);
+ }
+ ret = unwind_frame(tsk, &frame);
if (ret < 0)
break;
stack = frame.sp;
- if (in_exception_text(where))
+ if (in_exception_text(where)) {
+ /*
+ * If we switched to the irq_stack before calling this
+ * exception handler, then the pt_regs will be on the
+ * task stack. The easiest way to tell is if the large
+ * pt_regs would overlap with the end of the irq_stack.
+ */
+ if (stack < irq_stack_ptr &&
+ (stack + sizeof(struct pt_regs)) > irq_stack_ptr)
+ stack = IRQ_STACK_TO_TASK_STACK(irq_stack_ptr);
+
dump_mem("", "Exception stack", stack,
stack + sizeof(struct pt_regs), false);
+ }
}
+
+ put_task_stack(tsk);
}
void show_stack(struct task_struct *tsk, unsigned long *sp)
@@ -199,10 +246,9 @@ void show_stack(struct task_struct *tsk, unsigned long *sp)
#endif
#define S_SMP " SMP"
-static int __die(const char *str, int err, struct thread_info *thread,
- struct pt_regs *regs)
+static int __die(const char *str, int err, struct pt_regs *regs)
{
- struct task_struct *tsk = thread->task;
+ struct task_struct *tsk = current;
static int die_counter;
int ret;
@@ -217,7 +263,8 @@ static int __die(const char *str, int err, struct thread_info *thread,
print_modules();
__show_regs(regs);
pr_emerg("Process %.*s (pid: %d, stack limit = 0x%p)\n",
- TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);
+ TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk),
+ end_of_stack(tsk));
if (!user_mode(regs) || in_interrupt()) {
dump_mem(KERN_EMERG, "Stack: ", regs->sp,
@@ -237,7 +284,6 @@ static DEFINE_RAW_SPINLOCK(die_lock);
*/
void die(const char *str, struct pt_regs *regs, int err)
{
- struct thread_info *thread = current_thread_info();
int ret;
oops_enter();
@@ -245,9 +291,9 @@ void die(const char *str, struct pt_regs *regs, int err)
raw_spin_lock_irq(&die_lock);
console_verbose();
bust_spinlocks(1);
- ret = __die(str, err, thread, regs);
+ ret = __die(str, err, regs);
- if (regs && kexec_should_crash(thread->task))
+ if (regs && kexec_should_crash(current))
crash_kexec(regs);
bust_spinlocks(0);
@@ -364,6 +410,38 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
arm64_notify_die("Oops - undefined instruction", regs, &info, 0);
}
+static void cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
+{
+ int rt = (esr & ESR_ELx_SYS64_ISS_RT_MASK) >> ESR_ELx_SYS64_ISS_RT_SHIFT;
+
+ isb();
+ if (rt != 31)
+ regs->regs[rt] = arch_counter_get_cntvct();
+ regs->pc += 4;
+}
+
+static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
+{
+ int rt = (esr & ESR_ELx_SYS64_ISS_RT_MASK) >> ESR_ELx_SYS64_ISS_RT_SHIFT;
+
+ if (rt != 31)
+ regs->regs[rt] = read_sysreg(cntfrq_el0);
+ regs->pc += 4;
+}
+
+asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs)
+{
+ if ((esr & ESR_ELx_SYS64_ISS_SYS_OP_MASK) == ESR_ELx_SYS64_ISS_SYS_CNTVCT) {
+ cntvct_read_handler(esr, regs);
+ return;
+ } else if ((esr & ESR_ELx_SYS64_ISS_SYS_OP_MASK) == ESR_ELx_SYS64_ISS_SYS_CNTFRQ) {
+ cntfrq_read_handler(esr, regs);
+ return;
+ }
+
+ do_undefinstr(regs);
+}
+
long compat_arm_syscall(struct pt_regs *regs);
asmlinkage long do_ni_syscall(struct pt_regs *regs)
@@ -430,7 +508,7 @@ static const char *esr_class_str[] = {
const char *esr_get_class_string(u32 esr)
{
- return esr_class_str[esr >> ESR_ELx_EC_SHIFT];
+ return esr_class_str[ESR_ELx_EC(esr)];
}
/*
@@ -476,22 +554,22 @@ asmlinkage void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
void __pte_error(const char *file, int line, unsigned long val)
{
- pr_crit("%s:%d: bad pte %016lx.\n", file, line, val);
+ pr_err("%s:%d: bad pte %016lx.\n", file, line, val);
}
void __pmd_error(const char *file, int line, unsigned long val)
{
- pr_crit("%s:%d: bad pmd %016lx.\n", file, line, val);
+ pr_err("%s:%d: bad pmd %016lx.\n", file, line, val);
}
void __pud_error(const char *file, int line, unsigned long val)
{
- pr_crit("%s:%d: bad pud %016lx.\n", file, line, val);
+ pr_err("%s:%d: bad pud %016lx.\n", file, line, val);
}
void __pgd_error(const char *file, int line, unsigned long val)
{
- pr_crit("%s:%d: bad pgd %016lx.\n", file, line, val);
+ pr_err("%s:%d: bad pgd %016lx.\n", file, line, val);
}
/* GENERIC_BUG traps */
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-22 23:23:18 +0000