Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S
index 72be012..cef1d3f 100644
--- a/arch/arc/kernel/entry.S
+++ b/arch/arc/kernel/entry.S
@@ -35,6 +35,18 @@
 	b .Lret_from_system_call
 END(sys_clone_wrapper)
 
+ENTRY(sys_clone3_wrapper)
+	SAVE_CALLEE_SAVED_USER
+	bl  @sys_clone3
+	DISCARD_CALLEE_SAVED_USER
+
+	GET_CURR_THR_INFO_FLAGS   r10
+	btst r10, TIF_SYSCALL_TRACE
+	bnz  tracesys_exit
+
+	b .Lret_from_system_call
+END(sys_clone3_wrapper)
+
 ENTRY(ret_from_fork)
 	; when the forked child comes here from the __switch_to function
 	; r0 has the last task pointer.
@@ -153,7 +165,6 @@
 tracesys:
 	; save EFA in case tracer wants the PC of traced task
 	; using ERET won't work since next-PC has already committed
-	lr  r12, [efa]
 	GET_CURR_TASK_FIELD_PTR   TASK_THREAD, r11
 	st  r12, [r11, THREAD_FAULT_ADDR]	; thread.fault_address
 
@@ -166,7 +177,7 @@
 
 	; Do the Sys Call as we normally would.
 	; Validate the Sys Call number
-	cmp     r8,  NR_syscalls
+	cmp     r8,  NR_syscalls - 1
 	mov.hi  r0, -ENOSYS
 	bhi     tracesys_exit
 
@@ -196,15 +207,9 @@
 ; Breakpoint TRAP
 ; ---------------------------------------------
 trap_with_param:
-
-	; stop_pc info by gdb needs this info
-	lr  r0, [efa]
+	mov r0, r12	; EFA in case ptracer/gdb wants stop_pc
 	mov r1, sp
 
-	; Now that we have read EFA, it is safe to do "fake" rtie
-	;   and get out of CPU exception mode
-	FAKE_RET_FROM_EXCPN
-
 	; Save callee regs in case gdb wants to have a look
 	; SP will grow up by size of CALLEE Reg-File
 	; NOTE: clobbers r12
@@ -231,6 +236,10 @@
 
 	EXCEPTION_PROLOGUE
 
+	lr  r12, [efa]
+
+	FAKE_RET_FROM_EXCPN
+
 	;============ TRAP 1   :breakpoints
 	; Check ECR for trap with arg (PROLOGUE ensures r10 has ECR)
 	bmsk.f 0, r10, 7
@@ -238,9 +247,6 @@
 
 	;============ TRAP  (no param): syscall top level
 
-	; First return from Exception to pure K mode (Exception/IRQs renabled)
-	FAKE_RET_FROM_EXCPN
-
 	; If syscall tracing ongoing, invoke pre-post-hooks
 	GET_CURR_THR_INFO_FLAGS   r10
 	btst r10, TIF_SYSCALL_TRACE
@@ -249,7 +255,7 @@
 	;============ Normal syscall case
 
 	; syscall num shd not exceed the total system calls avail
-	cmp     r8,  NR_syscalls
+	cmp     r8,  NR_syscalls - 1
 	mov.hi  r0, -ENOSYS
 	bhi     .Lret_from_system_call
 
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
index 661fd84..145722f 100644
--- a/arch/arc/kernel/perf_event.c
+++ b/arch/arc/kernel/perf_event.c
@@ -562,7 +562,7 @@
 {
 	struct arc_reg_pct_build pct_bcr;
 	struct arc_reg_cc_build cc_bcr;
-	int i, has_interrupts;
+	int i, has_interrupts, irq = -1;
 	int counter_size;	/* in bits */
 
 	union cc_name {
@@ -638,22 +638,25 @@
 	};
 
 	if (has_interrupts) {
-		int irq = platform_get_irq(pdev, 0);
+		irq = platform_get_irq(pdev, 0);
+		if (irq >= 0) {
+			int ret;
 
-		if (irq < 0) {
-			pr_err("Cannot get IRQ number for the platform\n");
-			return -ENODEV;
+			arc_pmu->irq = irq;
+
+			/* intc map function ensures irq_set_percpu_devid() called */
+			ret = request_percpu_irq(irq, arc_pmu_intr, "ARC perf counters",
+						 this_cpu_ptr(&arc_pmu_cpu));
+
+			if (!ret)
+				on_each_cpu(arc_cpu_pmu_irq_init, &irq, 1);
+			else
+				irq = -1;
 		}
 
-		arc_pmu->irq = irq;
+	}
 
-		/* intc map function ensures irq_set_percpu_devid() called */
-		request_percpu_irq(irq, arc_pmu_intr, "ARC perf counters",
-				   this_cpu_ptr(&arc_pmu_cpu));
-
-		on_each_cpu(arc_cpu_pmu_irq_init, &irq, 1);
-
-	} else
+	if (irq == -1)
 		arc_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
 
 	/*
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index e1889ce..bfd4cbe 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -171,9 +171,8 @@
  * |    user_r25    |
  * ------------------  <===== END of PAGE
  */
-int copy_thread(unsigned long clone_flags,
-		unsigned long usp, unsigned long kthread_arg,
-		struct task_struct *p)
+int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
+	unsigned long kthread_arg, struct task_struct *p, unsigned long tls)
 {
 	struct pt_regs *c_regs;        /* child's pt_regs */
 	unsigned long *childksp;       /* to unwind out of __switch_to() */
@@ -231,7 +230,7 @@
 		 * set task's userland tls data ptr from 4th arg
 		 * clone C-lib call is difft from clone sys-call
 		 */
-		task_thread_info(p)->thr_ptr = regs->r3;
+		task_thread_info(p)->thr_ptr = tls;
 	} else {
 		/* Normal fork case: set parent's TLS ptr in child */
 		task_thread_info(p)->thr_ptr =
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index 7ee89dc..23dc002 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -12,6 +12,7 @@
 #include <linux/clocksource.h>
 #include <linux/console.h>
 #include <linux/module.h>
+#include <linux/sizes.h>
 #include <linux/cpu.h>
 #include <linux/of_fdt.h>
 #include <linux/of.h>
@@ -409,12 +410,12 @@
 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
 		panic("Linux built with incorrect DCCM Base address\n");
 
-	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
+	if (CONFIG_ARC_DCCM_SZ * SZ_1K != cpu->dccm.sz)
 		panic("Linux built with incorrect DCCM Size\n");
 #endif
 
 #ifdef CONFIG_ARC_HAS_ICCM
-	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
+	if (CONFIG_ARC_ICCM_SZ * SZ_1K != cpu->iccm.sz)
 		panic("Linux built with incorrect ICCM Size\n");
 #endif
 
diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c
index 3d57ed0..8877de0 100644
--- a/arch/arc/kernel/signal.c
+++ b/arch/arc/kernel/signal.c
@@ -61,6 +61,41 @@
 	unsigned int sigret_magic;
 };
 
+static int save_arcv2_regs(struct sigcontext *mctx, struct pt_regs *regs)
+{
+	int err = 0;
+#ifndef CONFIG_ISA_ARCOMPACT
+	struct user_regs_arcv2 v2abi;
+
+	v2abi.r30 = regs->r30;
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+	v2abi.r58 = regs->r58;
+	v2abi.r59 = regs->r59;
+#else
+	v2abi.r58 = v2abi.r59 = 0;
+#endif
+	err = __copy_to_user(&mctx->v2abi, &v2abi, sizeof(v2abi));
+#endif
+	return err;
+}
+
+static int restore_arcv2_regs(struct sigcontext *mctx, struct pt_regs *regs)
+{
+	int err = 0;
+#ifndef CONFIG_ISA_ARCOMPACT
+	struct user_regs_arcv2 v2abi;
+
+	err = __copy_from_user(&v2abi, &mctx->v2abi, sizeof(v2abi));
+
+	regs->r30 = v2abi.r30;
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+	regs->r58 = v2abi.r58;
+	regs->r59 = v2abi.r59;
+#endif
+#endif
+	return err;
+}
+
 static int
 stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs,
 	       sigset_t *set)
@@ -94,9 +129,13 @@
 
 	err = __copy_to_user(&(sf->uc.uc_mcontext.regs.scratch), &uregs.scratch,
 			     sizeof(sf->uc.uc_mcontext.regs.scratch));
+
+	if (is_isa_arcv2())
+		err |= save_arcv2_regs(&(sf->uc.uc_mcontext), regs);
+
 	err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t));
 
-	return err;
+	return err ? -EFAULT : 0;
 }
 
 static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
@@ -109,8 +148,12 @@
 	err |= __copy_from_user(&uregs.scratch,
 				&(sf->uc.uc_mcontext.regs.scratch),
 				sizeof(sf->uc.uc_mcontext.regs.scratch));
+
+	if (is_isa_arcv2())
+		err |= restore_arcv2_regs(&(sf->uc.uc_mcontext), regs);
+
 	if (err)
-		return err;
+		return -EFAULT;
 
 	set_current_blocked(&set);
 	regs->bta	= uregs.scratch.bta;
diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c
index 1e440bb..fc3054c 100644
--- a/arch/arc/kernel/stacktrace.c
+++ b/arch/arc/kernel/stacktrace.c
@@ -38,15 +38,15 @@
 
 #ifdef CONFIG_ARC_DW2_UNWIND
 
-static void seed_unwind_frame_info(struct task_struct *tsk,
-				   struct pt_regs *regs,
-				   struct unwind_frame_info *frame_info)
+static int
+seed_unwind_frame_info(struct task_struct *tsk, struct pt_regs *regs,
+		       struct unwind_frame_info *frame_info)
 {
 	/*
 	 * synchronous unwinding (e.g. dump_stack)
 	 *  - uses current values of SP and friends
 	 */
-	if (tsk == NULL && regs == NULL) {
+	if (regs == NULL && (tsk == NULL || tsk == current)) {
 		unsigned long fp, sp, blink, ret;
 		frame_info->task = current;
 
@@ -65,11 +65,15 @@
 		frame_info->call_frame = 0;
 	} else if (regs == NULL) {
 		/*
-		 * Asynchronous unwinding of sleeping task
-		 *  - Gets SP etc from task's pt_regs (saved bottom of kernel
-		 *    mode stack of task)
+		 * Asynchronous unwinding of a likely sleeping task
+		 *  - first ensure it is actually sleeping
+		 *  - if so, it will be in __switch_to, kernel mode SP of task
+		 *    is safe-kept and BLINK at a well known location in there
 		 */
 
+		if (tsk->state == TASK_RUNNING)
+			return -1;
+
 		frame_info->task = tsk;
 
 		frame_info->regs.r27 = TSK_K_FP(tsk);
@@ -103,6 +107,8 @@
 		frame_info->regs.r63 = regs->ret;
 		frame_info->call_frame = 0;
 	}
+
+	return 0;
 }
 
 #endif
@@ -112,11 +118,12 @@
 		int (*consumer_fn) (unsigned int, void *), void *arg)
 {
 #ifdef CONFIG_ARC_DW2_UNWIND
-	int ret = 0;
+	int ret = 0, cnt = 0;
 	unsigned int address;
 	struct unwind_frame_info frame_info;
 
-	seed_unwind_frame_info(tsk, regs, &frame_info);
+	if (seed_unwind_frame_info(tsk, regs, &frame_info))
+		return 0;
 
 	while (1) {
 		address = UNW_PC(&frame_info);
@@ -132,6 +139,11 @@
 			break;
 
 		frame_info.regs.r63 = frame_info.regs.r31;
+
+		if (cnt++ > 128) {
+			printk("unwinder looping too long, aborting !\n");
+			return 0;
+		}
 	}
 
 	return address;		/* return the last address it saw */
diff --git a/arch/arc/kernel/sys.c b/arch/arc/kernel/sys.c
index fddecc7..1069446 100644
--- a/arch/arc/kernel/sys.c
+++ b/arch/arc/kernel/sys.c
@@ -7,6 +7,7 @@
 #include <asm/syscalls.h>
 
 #define sys_clone	sys_clone_wrapper
+#define sys_clone3	sys_clone3_wrapper
 
 #undef __SYSCALL
 #define __SYSCALL(nr, call) [nr] = (call),
diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S
index 6c693a9..0391b82 100644
--- a/arch/arc/kernel/vmlinux.lds.S
+++ b/arch/arc/kernel/vmlinux.lds.S
@@ -88,6 +88,8 @@
 		CPUIDLE_TEXT
 		LOCK_TEXT
 		KPROBES_TEXT
+		IRQENTRY_TEXT
+		SOFTIRQENTRY_TEXT
 		*(.fixup)
 		*(.gnu.warning)
 	}