RISC-V Fixes for 6.1-rc5

* A fix to add the missing PWM LEDs into the  SiFive HiFive Unleashed
   device tree.
 * A fix to fully clear a task's registers on creation, as they end up in
   userspace and thus leak kernel memory.
 * A pair of VDSO-related build fixes that manifest on recent LLVM-based
   toolchains.
 * A fix to our early init to ensure the DT is adequately processed
   before reserved memory nodes are processed.
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Merge tag 'riscv-for-linus-6.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V fixes from Palmer Dabbelt:

 - A fix to add the missing PWM LEDs into the SiFive HiFive Unleashed
   device tree.

 - A fix to fully clear a task's registers on creation, as they end up
   in userspace and thus leak kernel memory.

 - A pair of VDSO-related build fixes that manifest on recent LLVM-based
   toolchains.

 - A fix to our early init to ensure the DT is adequately processed
   before reserved memory nodes are processed.

* tag 'riscv-for-linus-6.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  RISC-V: vdso: Do not add missing symbols to version section in linker script
  riscv: fix reserved memory setup
  riscv: vdso: fix build with llvm
  riscv: process: fix kernel info leakage
  riscv: dts: sifive unleashed: Add PWM controlled LEDs

arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts

@@ -3,6 +3,8 @@
 
 #include "fu540-c000.dtsi"
 #include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/leds/common.h>
+#include <dt-bindings/pwm/pwm.h>
 
 /* Clock frequency (in Hz) of the PCB crystal for rtcclk */
 #define RTCCLK_FREQ		1000000
@@ -42,6 +44,42 @@ gpio-restart {
 		compatible = "gpio-restart";
 		gpios = <&gpio 10 GPIO_ACTIVE_LOW>;
 	};
+
+	led-controller {
+		compatible = "pwm-leds";
+
+		led-d1 {
+			pwms = <&pwm0 0 7812500 PWM_POLARITY_INVERTED>;
+			active-low;
+			color = <LED_COLOR_ID_GREEN>;
+			max-brightness = <255>;
+			label = "d1";
+		};
+
+		led-d2 {
+			pwms = <&pwm0 1 7812500 PWM_POLARITY_INVERTED>;
+			active-low;
+			color = <LED_COLOR_ID_GREEN>;
+			max-brightness = <255>;
+			label = "d2";
+		};
+
+		led-d3 {
+			pwms = <&pwm0 2 7812500 PWM_POLARITY_INVERTED>;
+			active-low;
+			color = <LED_COLOR_ID_GREEN>;
+			max-brightness = <255>;
+			label = "d3";
+		};
+
+		led-d4 {
+			pwms = <&pwm0 3 7812500 PWM_POLARITY_INVERTED>;
+			active-low;
+			color = <LED_COLOR_ID_GREEN>;
+			max-brightness = <255>;
+			label = "d4";
+		};
+	};
 };
 
 &uart0 {

arch/riscv/kernel/process.c

@@ -164,6 +164,8 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 	unsigned long tls = args->tls;
 	struct pt_regs *childregs = task_pt_regs(p);
 
+	memset(&p->thread.s, 0, sizeof(p->thread.s));
+
 	/* p->thread holds context to be restored by __switch_to() */
 	if (unlikely(args->fn)) {
 		/* Kernel thread */

arch/riscv/kernel/setup.c

@@ -283,6 +283,7 @@ void __init setup_arch(char **cmdline_p)
 	else
 		pr_err("No DTB found in kernel mappings\n");
 #endif
+	early_init_fdt_scan_reserved_mem();
 	misc_mem_init();
 
 	init_resources();

arch/riscv/kernel/vdso/Makefile

@@ -28,9 +28,12 @@ obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
 
 obj-y += vdso.o
 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
+ifneq ($(filter vgettimeofday, $(vdso-syms)),)
+CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY
+endif
 
 # Disable -pg to prevent insert call site
-CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os
+CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
 
 # Disable profiling and instrumentation for VDSO code
 GCOV_PROFILE := n

arch/riscv/kernel/vdso/vdso.lds.S

@@ -68,9 +68,11 @@ VERSION
 	LINUX_4.15 {
 	global:
 		__vdso_rt_sigreturn;
+#ifdef HAS_VGETTIMEOFDAY
 		__vdso_gettimeofday;
 		__vdso_clock_gettime;
 		__vdso_clock_getres;
+#endif
 		__vdso_getcpu;
 		__vdso_flush_icache;
 	local: *;

arch/riscv/mm/init.c

@@ -262,7 +262,6 @@ static void __init setup_bootmem(void)
 			memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
 	}
 
-	early_init_fdt_scan_reserved_mem();
 	dma_contiguous_reserve(dma32_phys_limit);
 	if (IS_ENABLED(CONFIG_64BIT))
 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);