mm: add user fault debug support. [1/2]

PD#SWPL-73676

Problem:
need user fault debug support.

Solution:
add user fault debug support.

Verify:
local.

Change-Id: I6f48a5ec1cb75b276a15f6791ec09f2a2ed5d159
Signed-off-by: Jianxiong Pan <jianxiong.pan@amlogic.com>

arch/arm/kernel/process.c

@@ -33,6 +33,9 @@
 #include <asm/mach/time.h>
 #include <asm/tls.h>
 #include <asm/vdso.h>
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+#include <linux/amlogic/user_fault.h>
+#endif
 
 #include "signal.h"
 
@@ -127,6 +130,9 @@ void __show_regs(struct pt_regs *regs)
 
 	printk("PC is at %pS\n", (void *)instruction_pointer(regs));
 	printk("LR is at %pS\n", (void *)regs->ARM_lr);
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	show_user_fault_info(regs, 0, 0);
+#endif
 	printk("pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n",
 	       regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr);
 	printk("sp : %08lx  ip : %08lx  fp : %08lx\n",
@@ -148,6 +154,10 @@ void __show_regs(struct pt_regs *regs)
 	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
 	buf[4] = '\0';
 
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	show_vmalloc_pfn(regs);
+#endif
+
 #ifndef CONFIG_CPU_V7M
 	{
 		const char *segment;
@@ -187,6 +197,9 @@ void __show_regs(struct pt_regs *regs)
 		printk("Control: %08x%s\n", ctrl, buf);
 	}
 #endif
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	show_extra_reg_data(regs);
+#endif
 }
 
 void show_regs(struct pt_regs * regs)

arch/arm/kernel/traps.c

@@ -38,6 +38,9 @@
 #include <asm/tls.h>
 #include <asm/system_misc.h>
 #include <asm/opcodes.h>
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+#include <linux/amlogic/user_fault.h>
+#endif
 
 
 static const char *handler[]= {
@@ -51,7 +54,20 @@ static const char *handler[]= {
 void *vectors_page;
 
 #ifdef CONFIG_DEBUG_USER
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+#define USER_DEBUG_UNDEFINED_INSTRUCTION BIT(0)
+#define USER_DEBUG_SYSTEM_CALL           BIT(1)
+#define USER_DEBUG_INVALID_DATA_ABORT    BIT(2)
+#define USER_DEBUG_SIGSEGV_FAULT         BIT(3)
+#define USER_DEBUG_SIGBUS_FAULT          BIT(14)
+unsigned int user_debug = USER_DEBUG_UNDEFINED_INSTRUCTION |
+			  USER_DEBUG_SYSTEM_CALL |
+			  USER_DEBUG_INVALID_DATA_ABORT |
+			  USER_DEBUG_SIGSEGV_FAULT |
+			  USER_DEBUG_SIGBUS_FAULT;
+#else
 unsigned int user_debug;
+#endif
 
 static int __init user_debug_setup(char *str)
 {
@@ -473,6 +489,9 @@ die_sig:
 	if (user_debug & UDBG_UNDEFINED) {
 		pr_info("%s (%d): undefined instruction: pc=%p\n",
 			current->comm, task_pid_nr(current), pc);
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+		show_debug_ratelimited(regs, 0);
+#endif
 		__show_regs(regs);
 		dump_instr(KERN_INFO, regs);
 	}
@@ -517,6 +536,9 @@ asmlinkage void bad_mode(struct pt_regs *regs, int reason)
 {
 	console_verbose();
 
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	show_debug_ratelimited(regs, 0);
+#endif
 	pr_crit("Bad mode in %s handler detected\n", handler[reason]);
 
 	die("Oops - bad mode", regs, 0);

arch/arm/mm/fault.c

@@ -21,6 +21,9 @@
 #include <asm/system_misc.h>
 #include <asm/system_info.h>
 #include <asm/tlbflush.h>
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+#include <linux/amlogic/user_fault.h>
+#endif
 
 #include "fault.h"
 
@@ -142,13 +145,28 @@ __do_user_fault(unsigned long addr, unsigned int fsr, unsigned int sig,
 		harden_branch_predictor();
 
 #ifdef CONFIG_DEBUG_USER
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	if (unhandled_signal(tsk, sig) &&
+	    (((user_debug & UDBG_SEGV) && sig == SIGSEGV) ||
+	     ((user_debug & UDBG_BUS)  && sig == SIGBUS))) {
+#else
 	if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) ||
 	    ((user_debug & UDBG_BUS)  && (sig == SIGBUS))) {
+#endif
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+		pr_info("%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n",
+			tsk->comm, sig, addr, fsr);
+#else
 		pr_err("8<--- cut here ---\n");
 		pr_err("%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n",
 		       tsk->comm, sig, addr, fsr);
+#endif
 		show_pte(KERN_ERR, tsk->mm, addr);
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+		show_debug_ratelimited(regs, 1);
+#else
 		show_regs(regs);
+#endif
 	}
 #endif
 #ifndef CONFIG_KUSER_HELPERS

arch/arm64/kernel/process.c

@@ -57,6 +57,9 @@
 #include <asm/stacktrace.h>
 #include <asm/switch_to.h>
 #include <asm/system_misc.h>
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+#include <linux/amlogic/user_fault.h>
+#endif
 
 #if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_STACKPROTECTOR_PER_TASK)
 #include <linux/stackprotector.h>
@@ -215,6 +218,10 @@ void __show_regs(struct pt_regs *regs)
 		top_reg = 29;
 	}
 
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	show_user_fault_info(regs, lr, sp);
+#endif /* CONFIG_AMLOGIC_USER_FAULT */
+
 	show_regs_print_info(KERN_DEFAULT);
 	print_pstate(regs);
 
@@ -241,6 +248,9 @@ void __show_regs(struct pt_regs *regs)
 
 		pr_cont("\n");
 	}
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	show_extra_reg_data(regs);
+#endif /* CONFIG_AMLOGIC_USER_FAULT */
 }
 
 void show_regs(struct pt_regs *regs)

arch/arm64/kernel/traps.c

@@ -48,6 +48,10 @@
 
 #include <trace/hooks/traps.h>
 
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+#include <linux/amlogic/user_fault.h>
+#endif
+
 static bool __kprobes __check_eq(unsigned long pstate)
 {
 	return (pstate & PSR_Z_BIT) != 0;
@@ -146,7 +150,11 @@ pstate_check_t * const aarch32_opcode_cond_checks[16] = {
 	__check_gt, __check_le, __check_al, __check_al
 };
 
+#ifndef CONFIG_AMLOGIC_USER_FAULT
 int show_unhandled_signals = 0;
+#else
+int show_unhandled_signals = 1;
+#endif
 
 static void dump_kernel_instr(const char *lvl, struct pt_regs *regs)
 {
@@ -249,9 +257,16 @@ static void arm64_show_signal(int signo, const char *str)
 	struct pt_regs *regs = task_pt_regs(tsk);
 
 	/* Leave if the signal won't be shown */
+#ifndef CONFIG_AMLOGIC_USER_FAULT
 	if (!show_unhandled_signals ||
 	    !unhandled_signal(tsk, signo) ||
 	    !__ratelimit(&rs))
+#else
+	if (!show_unhandled_signals ||
+		(!unhandled_signal(tsk, signo) &&
+		!(show_unhandled_signals & 0xe)) ||
+		!__ratelimit(&rs))
+#endif
 		return;
 
 	pr_info("%s[%d]: unhandled exception: ", tsk->comm, task_pid_nr(tsk));
@@ -262,6 +277,12 @@ static void arm64_show_signal(int signo, const char *str)
 	print_vma_addr(KERN_CONT " in ", regs->pc);
 	pr_cont("\n");
 	__show_regs(regs);
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	pr_info("signo: %d\n", signo);
+	show_all_pfn(current, regs);
+	if (regs && kexec_should_crash(current) && (show_unhandled_signals & 4))
+		crash_kexec(regs);
+#endif
 }
 
 void arm64_force_sig_fault(int signo, int code, unsigned long far,
@@ -848,6 +869,10 @@ void bad_el0_sync(struct pt_regs *regs, int reason, unsigned long esr)
 	current->thread.fault_address = 0;
 	current->thread.fault_code = esr;
 
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+	show_all_pfn(current, regs);
+#endif /* CONFIG_AMLOGIC_USER_FAULT */
+
 	arm64_force_sig_fault(SIGILL, ILL_ILLOPC, pc,
 			      "Bad EL0 synchronous exception");
 }

arch/arm64/mm/fault.c

@@ -46,6 +46,10 @@
 
 #include <trace/hooks/fault.h>
 
+#ifdef CONFIG_AMLOGIC_USER_FAULT
+#include <linux/amlogic/user_fault.h>
+#endif
+
 struct fault_info {
 	int	(*fn)(unsigned long far, unsigned long esr,
 		      struct pt_regs *regs);