19 files changed, 151 insertions, 57 deletions

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index e0d7d61779a6..515fc3cc9687 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -28,11 +28,13 @@ config RISCV
 	select GENERIC_STRNLEN_USER
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A
+	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_MEMBLOCK_NODE_MAP
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_PERF_EVENTS
+	select HAVE_SYSCALL_TRACEPOINTS
 	select IRQ_DOMAIN
 	select RISCV_ISA_A if SMP
 	select SPARSE_IRQ
@@ -40,6 +42,7 @@ config RISCV
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_PCI
 	select MODULES_USE_ELF_RELA if MODULES
+	select MODULE_SECTIONS if MODULES
 	select THREAD_INFO_IN_TASK
 	select PCI_DOMAINS_GENERIC if PCI
 	select PCI_MSI if PCI
@@ -100,7 +103,7 @@ choice
 	prompt "Base ISA"
 	default ARCH_RV64I
 	help
-	  This selects the base ISA that this kernel will traget and must match
+	  This selects the base ISA that this kernel will target and must match
 	  the target platform.
 
 config ARCH_RV32I
@@ -152,7 +155,6 @@ choice
 		bool "2GiB"
 	config MAXPHYSMEM_128GB
 		depends on 64BIT && CMODEL_MEDANY
-		select MODULE_SECTIONS if MODULES
 		bool "128GiB"
 endchoice
 
diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
index f399659d3b8d..2fd3461e50ab 100644
--- a/arch/riscv/configs/defconfig
+++ b/arch/riscv/configs/defconfig
@@ -13,8 +13,6 @@ CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
 CONFIG_BPF_SYSCALL=y
 CONFIG_SMP=y
-CONFIG_PCI=y
-CONFIG_PCIE_XILINX=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y
 CONFIG_NET=y
@@ -28,6 +26,10 @@ CONFIG_IP_PNP_DHCP=y
 CONFIG_IP_PNP_BOOTP=y
 CONFIG_IP_PNP_RARP=y
 CONFIG_NETLINK_DIAG=y
+CONFIG_PCI=y
+CONFIG_PCIEPORTBUS=y
+CONFIG_PCI_HOST_GENERIC=y
+CONFIG_PCIE_XILINX=y
 CONFIG_DEVTMPFS=y
 CONFIG_BLK_DEV_LOOP=y
 CONFIG_VIRTIO_BLK=y
@@ -63,7 +65,6 @@ CONFIG_USB_STORAGE=y
 CONFIG_USB_UAS=y
 CONFIG_VIRTIO_MMIO=y
 CONFIG_SIFIVE_PLIC=y
-CONFIG_RAS=y
 CONFIG_EXT4_FS=y
 CONFIG_EXT4_FS_POSIX_ACL=y
 CONFIG_AUTOFS4_FS=y
@@ -77,5 +78,6 @@ CONFIG_NFS_V4_1=y
 CONFIG_NFS_V4_2=y
 CONFIG_ROOT_NFS=y
 CONFIG_CRYPTO_USER_API_HASH=y
+CONFIG_CRYPTO_DEV_VIRTIO=y
 CONFIG_PRINTK_TIME=y
 # CONFIG_RCU_TRACE is not set
diff --git a/arch/riscv/include/asm/module.h b/arch/riscv/include/asm/module.h
index cd2af4b013e3..46202dad365d 100644
--- a/arch/riscv/include/asm/module.h
+++ b/arch/riscv/include/asm/module.h
@@ -9,12 +9,12 @@
 #define MODULE_ARCH_VERMAGIC    "riscv"
 
 struct module;
-u64 module_emit_got_entry(struct module *mod, u64 val);
-u64 module_emit_plt_entry(struct module *mod, u64 val);
+unsigned long module_emit_got_entry(struct module *mod, unsigned long val);
+unsigned long module_emit_plt_entry(struct module *mod, unsigned long val);
 
 #ifdef CONFIG_MODULE_SECTIONS
 struct mod_section {
-	struct elf64_shdr *shdr;
+	Elf_Shdr *shdr;
 	int num_entries;
 	int max_entries;
 };
@@ -26,18 +26,18 @@ struct mod_arch_specific {
 };
 
 struct got_entry {
-	u64 symbol_addr;	/* the real variable address */
+	unsigned long symbol_addr;	/* the real variable address */
 };
 
-static inline struct got_entry emit_got_entry(u64 val)
+static inline struct got_entry emit_got_entry(unsigned long val)
 {
 	return (struct got_entry) {val};
 }
 
-static inline struct got_entry *get_got_entry(u64 val,
+static inline struct got_entry *get_got_entry(unsigned long val,
 					      const struct mod_section *sec)
 {
-	struct got_entry *got = (struct got_entry *)sec->shdr->sh_addr;
+	struct got_entry *got = (struct got_entry *)(sec->shdr->sh_addr);
 	int i;
 	for (i = 0; i < sec->num_entries; i++) {
 		if (got[i].symbol_addr == val)
@@ -62,7 +62,9 @@ struct plt_entry {
 #define REG_T0     0x5
 #define REG_T1     0x6
 
-static inline struct plt_entry emit_plt_entry(u64 val, u64 plt, u64 got_plt)
+static inline struct plt_entry emit_plt_entry(unsigned long val,
+					      unsigned long plt,
+					      unsigned long got_plt)
 {
 	/*
 	 * U-Type encoding:
@@ -76,7 +78,7 @@ static inline struct plt_entry emit_plt_entry(u64 val, u64 plt, u64 got_plt)
 	 * +------------+------------+--------+----------+----------+
 	 *
 	 */
-	u64 offset = got_plt - plt;
+	unsigned long offset = got_plt - plt;
 	u32 hi20 = (offset + 0x800) & 0xfffff000;
 	u32 lo12 = (offset - hi20);
 	return (struct plt_entry) {
@@ -86,7 +88,7 @@ static inline struct plt_entry emit_plt_entry(u64 val, u64 plt, u64 got_plt)
 	};
 }
 
-static inline int get_got_plt_idx(u64 val, const struct mod_section *sec)
+static inline int get_got_plt_idx(unsigned long val, const struct mod_section *sec)
 {
 	struct got_entry *got_plt = (struct got_entry *)sec->shdr->sh_addr;
 	int i;
@@ -97,9 +99,9 @@ static inline int get_got_plt_idx(u64 val, const struct mod_section *sec)
 	return -1;
 }
 
-static inline struct plt_entry *get_plt_entry(u64 val,
-				      const struct mod_section *sec_plt,
-				      const struct mod_section *sec_got_plt)
+static inline struct plt_entry *get_plt_entry(unsigned long val,
+					      const struct mod_section *sec_plt,
+					      const struct mod_section *sec_got_plt)
 {
 	struct plt_entry *plt = (struct plt_entry *)sec_plt->shdr->sh_addr;
 	int got_plt_idx = get_got_plt_idx(val, sec_got_plt);
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
index 06cfbb3aacbb..2a546a52f02a 100644
--- a/arch/riscv/include/asm/page.h
+++ b/arch/riscv/include/asm/page.h
@@ -80,7 +80,7 @@ typedef struct page *pgtable_t;
 #define __pgd(x)	((pgd_t) { (x) })
 #define __pgprot(x)	((pgprot_t) { (x) })
 
-#ifdef CONFIG_64BITS
+#ifdef CONFIG_64BIT
 #define PTE_FMT "%016lx"
 #else
 #define PTE_FMT "%08lx"
diff --git a/arch/riscv/include/asm/pgtable-bits.h b/arch/riscv/include/asm/pgtable-bits.h
index 2fa2942be221..470755cb7558 100644
--- a/arch/riscv/include/asm/pgtable-bits.h
+++ b/arch/riscv/include/asm/pgtable-bits.h
@@ -35,6 +35,12 @@
 #define _PAGE_SPECIAL   _PAGE_SOFT
 #define _PAGE_TABLE     _PAGE_PRESENT
 
+/*
+ * _PAGE_PROT_NONE is set on not-present pages (and ignored by the hardware) to
+ * distinguish them from swapped out pages
+ */
+#define _PAGE_PROT_NONE _PAGE_READ
+
 #define _PAGE_PFN_SHIFT 10
 
 /* Set of bits to preserve across pte_modify() */
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 16301966d65b..a8179a8c1491 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -44,7 +44,7 @@
 /* Page protection bits */
 #define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_USER)
 
-#define PAGE_NONE		__pgprot(0)
+#define PAGE_NONE		__pgprot(_PAGE_PROT_NONE)
 #define PAGE_READ		__pgprot(_PAGE_BASE | _PAGE_READ)
 #define PAGE_WRITE		__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE)
 #define PAGE_EXEC		__pgprot(_PAGE_BASE | _PAGE_EXEC)
@@ -98,7 +98,7 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
 
 static inline int pmd_present(pmd_t pmd)
 {
-	return (pmd_val(pmd) & _PAGE_PRESENT);
+	return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
 }
 
 static inline int pmd_none(pmd_t pmd)
@@ -178,7 +178,7 @@ static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long addr)
 
 static inline int pte_present(pte_t pte)
 {
-	return (pte_val(pte) & _PAGE_PRESENT);
+	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
 }
 
 static inline int pte_none(pte_t pte)
@@ -380,7 +380,7 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
  *
  * Format of swap PTE:
  *	bit            0:	_PAGE_PRESENT (zero)
- *	bit            1:	reserved for future use (zero)
+ *	bit            1:	_PAGE_PROT_NONE (zero)
  *	bits      2 to 6:	swap type
  *	bits 7 to XLEN-1:	swap offset
  */
diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
index 0531f49af5c3..ce70bceb8872 100644
--- a/arch/riscv/include/asm/processor.h
+++ b/arch/riscv/include/asm/processor.h
@@ -22,7 +22,7 @@
  * This decides where the kernel will search for a free chunk of vm
  * space during mmap's.
  */
-#define TASK_UNMAPPED_BASE	PAGE_ALIGN(TASK_SIZE >> 1)
+#define TASK_UNMAPPED_BASE	PAGE_ALIGN(TASK_SIZE / 3)
 
 #define STACK_TOP		TASK_SIZE
 #define STACK_TOP_MAX		STACK_TOP
diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h
index bbe1862e8f80..d35ec2f41381 100644
--- a/arch/riscv/include/asm/ptrace.h
+++ b/arch/riscv/include/asm/ptrace.h
@@ -113,6 +113,11 @@ static inline void frame_pointer_set(struct pt_regs *regs,
 	SET_FP(regs, val);
 }
 
+static inline unsigned long regs_return_value(struct pt_regs *regs)
+{
+	return regs->a0;
+}
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_RISCV_PTRACE_H */
diff --git a/arch/riscv/include/asm/syscall.h b/arch/riscv/include/asm/syscall.h
index 8d25f8904c00..bba3da6ef157 100644
--- a/arch/riscv/include/asm/syscall.h
+++ b/arch/riscv/include/asm/syscall.h
@@ -18,6 +18,7 @@
 #ifndef _ASM_RISCV_SYSCALL_H
 #define _ASM_RISCV_SYSCALL_H
 
+#include <uapi/linux/audit.h>
 #include <linux/sched.h>
 #include <linux/err.h>
 
@@ -99,4 +100,13 @@ static inline void syscall_set_arguments(struct task_struct *task,
 	memcpy(&regs->a1 + i * sizeof(regs->a1), args, n * sizeof(regs->a0));
 }
 
+static inline int syscall_get_arch(void)
+{
+#ifdef CONFIG_64BIT
+	return AUDIT_ARCH_RISCV64;
+#else
+	return AUDIT_ARCH_RISCV32;
+#endif
+}
+
 #endif	/* _ASM_RISCV_SYSCALL_H */
diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h
index f8fa1cd2dad9..1c9cc8389928 100644
--- a/arch/riscv/include/asm/thread_info.h
+++ b/arch/riscv/include/asm/thread_info.h
@@ -80,13 +80,19 @@ struct thread_info {
 #define TIF_RESTORE_SIGMASK	4	/* restore signal mask in do_signal() */
 #define TIF_MEMDIE		5	/* is terminating due to OOM killer */
 #define TIF_SYSCALL_TRACEPOINT  6       /* syscall tracepoint instrumentation */
+#define TIF_SYSCALL_AUDIT	7	/* syscall auditing */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
+#define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
+#define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
 
 #define _TIF_WORK_MASK \
 	(_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED)
 
+#define _TIF_SYSCALL_WORK \
+	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT)
+
 #endif /* _ASM_RISCV_THREAD_INFO_H */
diff --git a/arch/riscv/include/asm/unistd.h b/arch/riscv/include/asm/unistd.h
index fef96f117b4d..073ee80fdf74 100644
--- a/arch/riscv/include/asm/unistd.h
+++ b/arch/riscv/include/asm/unistd.h
@@ -19,3 +19,5 @@
 #define __ARCH_WANT_SYS_CLONE
 
 #include <uapi/asm/unistd.h>
+
+#define NR_syscalls (__NR_syscalls)
diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c
index 6a92a2fe198e..dac98348c6a3 100644
--- a/arch/riscv/kernel/asm-offsets.c
+++ b/arch/riscv/kernel/asm-offsets.c
@@ -39,6 +39,7 @@ void asm_offsets(void)
 	OFFSET(TASK_STACK, task_struct, stack);
 	OFFSET(TASK_TI, task_struct, thread_info);
 	OFFSET(TASK_TI_FLAGS, task_struct, thread_info.flags);
+	OFFSET(TASK_TI_PREEMPT_COUNT, task_struct, thread_info.preempt_count);
 	OFFSET(TASK_TI_KERNEL_SP, task_struct, thread_info.kernel_sp);
 	OFFSET(TASK_TI_USER_SP, task_struct, thread_info.user_sp);
 	OFFSET(TASK_TI_CPU, task_struct, thread_info.cpu);
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 13d4826ab2a1..fd9b57c8b4ce 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -144,6 +144,10 @@ _save_context:
 	REG_L x2,  PT_SP(sp)
 	.endm
 
+#if !IS_ENABLED(CONFIG_PREEMPT)
+.set resume_kernel, restore_all
+#endif
+
 ENTRY(handle_exception)
 	SAVE_ALL
 
@@ -201,7 +205,7 @@ handle_syscall:
 	REG_S s2, PT_SEPC(sp)
 	/* Trace syscalls, but only if requested by the user. */
 	REG_L t0, TASK_TI_FLAGS(tp)
-	andi t0, t0, _TIF_SYSCALL_TRACE
+	andi t0, t0, _TIF_SYSCALL_WORK
 	bnez t0, handle_syscall_trace_enter
 check_syscall_nr:
 	/* Check to make sure we don't jump to a bogus syscall number. */
@@ -221,14 +225,14 @@ ret_from_syscall:
 	REG_S a0, PT_A0(sp)
 	/* Trace syscalls, but only if requested by the user. */
 	REG_L t0, TASK_TI_FLAGS(tp)
-	andi t0, t0, _TIF_SYSCALL_TRACE
+	andi t0, t0, _TIF_SYSCALL_WORK
 	bnez t0, handle_syscall_trace_exit
 
 ret_from_exception:
 	REG_L s0, PT_SSTATUS(sp)
 	csrc sstatus, SR_SIE
 	andi s0, s0, SR_SPP
-	bnez s0, restore_all
+	bnez s0, resume_kernel
 
 resume_userspace:
 	/* Interrupts must be disabled here so flags are checked atomically */
@@ -250,6 +254,18 @@ restore_all:
 	RESTORE_ALL
 	sret
 
+#if IS_ENABLED(CONFIG_PREEMPT)
+resume_kernel:
+	REG_L s0, TASK_TI_PREEMPT_COUNT(tp)
+	bnez s0, restore_all
+need_resched:
+	REG_L s0, TASK_TI_FLAGS(tp)
+	andi s0, s0, _TIF_NEED_RESCHED
+	beqz s0, restore_all
+	call preempt_schedule_irq
+	j need_resched
+#endif
+
 work_pending:
 	/* Enter slow path for supplementary processing */
 	la ra, ret_from_exception
diff --git a/arch/riscv/kernel/module-sections.c b/arch/riscv/kernel/module-sections.c
index bbbd26e19bfd..c9ae48333114 100644
--- a/arch/riscv/kernel/module-sections.c
+++ b/arch/riscv/kernel/module-sections.c
@@ -9,14 +9,14 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 
-u64 module_emit_got_entry(struct module *mod, u64 val)
+unsigned long module_emit_got_entry(struct module *mod, unsigned long val)
 {
 	struct mod_section *got_sec = &mod->arch.got;
 	int i = got_sec->num_entries;
 	struct got_entry *got = get_got_entry(val, got_sec);
 
 	if (got)
-		return (u64)got;
+		return (unsigned long)got;
 
 	/* There is no duplicate entry, create a new one */
 	got = (struct got_entry *)got_sec->shdr->sh_addr;
@@ -25,10 +25,10 @@ u64 module_emit_got_entry(struct module *mod, u64 val)
 	got_sec->num_entries++;
 	BUG_ON(got_sec->num_entries > got_sec->max_entries);
 
-	return (u64)&got[i];
+	return (unsigned long)&got[i];
 }
 
-u64 module_emit_plt_entry(struct module *mod, u64 val)
+unsigned long module_emit_plt_entry(struct module *mod, unsigned long val)
 {
 	struct mod_section *got_plt_sec = &mod->arch.got_plt;
 	struct got_entry *got_plt;
@@ -37,27 +37,29 @@ u64 module_emit_plt_entry(struct module *mod, u64 val)
 	int i = plt_sec->num_entries;
 
 	if (plt)
-		return (u64)plt;
+		return (unsigned long)plt;
 
 	/* There is no duplicate entry, create a new one */
 	got_plt = (struct got_entry *)got_plt_sec->shdr->sh_addr;
 	got_plt[i] = emit_got_entry(val);
 	plt = (struct plt_entry *)plt_sec->shdr->sh_addr;
-	plt[i] = emit_plt_entry(val, (u64)&plt[i], (u64)&got_plt[i]);
+	plt[i] = emit_plt_entry(val,
+				(unsigned long)&plt[i],
+				(unsigned long)&got_plt[i]);
 
 	plt_sec->num_entries++;
 	got_plt_sec->num_entries++;
 	BUG_ON(plt_sec->num_entries > plt_sec->max_entries);
 
-	return (u64)&plt[i];
+	return (unsigned long)&plt[i];
 }
 
-static int is_rela_equal(const Elf64_Rela *x, const Elf64_Rela *y)
+static int is_rela_equal(const Elf_Rela *x, const Elf_Rela *y)
 {
 	return x->r_info == y->r_info && x->r_addend == y->r_addend;
 }
 
-static bool duplicate_rela(const Elf64_Rela *rela, int idx)
+static bool duplicate_rela(const Elf_Rela *rela, int idx)
 {
 	int i;
 	for (i = 0; i < idx; i++) {
@@ -67,13 +69,13 @@ static bool duplicate_rela(const Elf64_Rela *rela, int idx)
 	return false;
 }
 
-static void count_max_entries(Elf64_Rela *relas, int num,
+static void count_max_entries(Elf_Rela *relas, int num,
 			      unsigned int *plts, unsigned int *gots)
 {
 	unsigned int type, i;
 
 	for (i = 0; i < num; i++) {
-		type = ELF64_R_TYPE(relas[i].r_info);
+		type = ELF_RISCV_R_TYPE(relas[i].r_info);
 		if (type == R_RISCV_CALL_PLT) {
 			if (!duplicate_rela(relas, i))
 				(*plts)++;
@@ -118,9 +120,9 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 
 	/* Calculate the maxinum number of entries */
 	for (i = 0; i < ehdr->e_shnum; i++) {
-		Elf64_Rela *relas = (void *)ehdr + sechdrs[i].sh_offset;
-		int num_rela = sechdrs[i].sh_size / sizeof(Elf64_Rela);
-		Elf64_Shdr *dst_sec = sechdrs + sechdrs[i].sh_info;
+		Elf_Rela *relas = (void *)ehdr + sechdrs[i].sh_offset;
+		int num_rela = sechdrs[i].sh_size / sizeof(Elf_Rela);
+		Elf_Shdr *dst_sec = sechdrs + sechdrs[i].sh_info;
 
 		if (sechdrs[i].sh_type != SHT_RELA)
 			continue;
diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
index 60f1e02eed36..2ae5e0284f56 100644
--- a/arch/riscv/kernel/ptrace.c
+++ b/arch/riscv/kernel/ptrace.c
@@ -18,12 +18,15 @@
 #include <asm/ptrace.h>
 #include <asm/syscall.h>
 #include <asm/thread_info.h>
+#include <linux/audit.h>
 #include <linux/ptrace.h>
 #include <linux/elf.h>
 #include <linux/regset.h>
 #include <linux/sched.h>
 #include <linux/sched/task_stack.h>
 #include <linux/tracehook.h>
+
+#define CREATE_TRACE_POINTS
 #include <trace/events/syscalls.h>
 
 enum riscv_regset {
@@ -163,15 +166,19 @@ void do_syscall_trace_enter(struct pt_regs *regs)
 	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
 		trace_sys_enter(regs, syscall_get_nr(current, regs));
 #endif
+
+	audit_syscall_entry(regs->a7, regs->a0, regs->a1, regs->a2, regs->a3);
 }
 
 void do_syscall_trace_exit(struct pt_regs *regs)
 {
+	audit_syscall_exit(regs);
+
 	if (test_thread_flag(TIF_SYSCALL_TRACE))
 		tracehook_report_syscall_exit(regs, 0);
 
 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
 	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
-		trace_sys_exit(regs, regs->regs[0]);
+		trace_sys_exit(regs, regs_return_value(regs));
 #endif
 }
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index fc8006a042eb..77564310235f 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -149,7 +149,14 @@ asmlinkage void __init setup_vm(void)
 
 void __init parse_dtb(unsigned int hartid, void *dtb)
 {
-	early_init_dt_scan(__va(dtb));
+	if (!early_init_dt_scan(__va(dtb)))
+		return;
+
+	pr_err("No DTB passed to the kernel\n");
+#ifdef CONFIG_CMDLINE_FORCE
+	strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+	pr_info("Forcing kernel command line to: %s\n", boot_command_line);
+#endif
 }
 
 static void __init setup_bootmem(void)
@@ -174,7 +181,7 @@ static void __init setup_bootmem(void)
 	BUG_ON(mem_size == 0);
 
 	set_max_mapnr(PFN_DOWN(mem_size));
-	max_low_pfn = memblock_end_of_DRAM();
+	max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
 
 #ifdef CONFIG_BLK_DEV_INITRD
 	setup_initrd();
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 57b1383e5ef7..246635eac7bb 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -23,6 +23,7 @@
 #include <linux/smp.h>
 #include <linux/sched.h>
 #include <linux/seq_file.h>
+#include <linux/delay.h>
 
 #include <asm/sbi.h>
 #include <asm/tlbflush.h>
@@ -31,6 +32,7 @@
 enum ipi_message_type {
 	IPI_RESCHEDULE,
 	IPI_CALL_FUNC,
+	IPI_CPU_STOP,
 	IPI_MAX
 };
 
@@ -66,6 +68,13 @@ int setup_profiling_timer(unsigned int multiplier)
 	return -EINVAL;
 }
 
+static void ipi_stop(void)
+{
+	set_cpu_online(smp_processor_id(), false);
+	while (1)
+		wait_for_interrupt();
+}
+
 void riscv_software_interrupt(void)
 {
 	unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
@@ -94,6 +103,11 @@ void riscv_software_interrupt(void)
 			generic_smp_call_function_interrupt();
 		}
 
+		if (ops & (1 << IPI_CPU_STOP)) {
+			stats[IPI_CPU_STOP]++;
+			ipi_stop();
+		}
+
 		BUG_ON((ops >> IPI_MAX) != 0);
 
 		/* Order data access and bit testing. */
@@ -121,6 +135,7 @@ send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation)
 static const char * const ipi_names[] = {
 	[IPI_RESCHEDULE]	= "Rescheduling interrupts",
 	[IPI_CALL_FUNC]		= "Function call interrupts",
+	[IPI_CPU_STOP]		= "CPU stop interrupts",
 };
 
 void show_ipi_stats(struct seq_file *p, int prec)
@@ -146,15 +161,29 @@ void arch_send_call_function_single_ipi(int cpu)
 	send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
-static void ipi_stop(void *unused)
-{
-	while (1)
-		wait_for_interrupt();
-}
-
 void smp_send_stop(void)
 {
-	on_each_cpu(ipi_stop, NULL, 1);
+	unsigned long timeout;
+
+	if (num_online_cpus() > 1) {
+		cpumask_t mask;
+
+		cpumask_copy(&mask, cpu_online_mask);
+		cpumask_clear_cpu(smp_processor_id(), &mask);
+
+		if (system_state <= SYSTEM_RUNNING)
+			pr_crit("SMP: stopping secondary CPUs\n");
+		send_ipi_message(&mask, IPI_CPU_STOP);
+	}
+
+	/* Wait up to one second for other CPUs to stop */
+	timeout = USEC_PER_SEC;
+	while (num_online_cpus() > 1 && timeout--)
+		udelay(1);
+
+	if (num_online_cpus() > 1)
+		pr_warn("SMP: failed to stop secondary CPUs %*pbl\n",
+			   cpumask_pr_args(cpu_online_mask));
 }
 
 void smp_send_reschedule(int cpu)
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index fc185ecabb0a..18cda0e8cf94 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -57,15 +57,12 @@ void __init setup_smp(void)
 
 	while ((dn = of_find_node_by_type(dn, "cpu"))) {
 		hart = riscv_of_processor_hartid(dn);
-		if (hart < 0) {
-			of_node_put(dn);
+		if (hart < 0)
 			continue;
-		}
 
 		if (hart == cpuid_to_hartid_map(0)) {
 			BUG_ON(found_boot_cpu);
 			found_boot_cpu = 1;
-			of_node_put(dn);
 			continue;
 		}
 
@@ -73,7 +70,6 @@ void __init setup_smp(void)
 		set_cpu_possible(cpuid, true);
 		set_cpu_present(cpuid, true);
 		cpuid++;
-		of_node_put(dn);
 	}
 
 	BUG_ON(!found_boot_cpu);
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 1d9bfaff60bc..658ebf645f42 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -28,7 +28,8 @@ static void __init zone_sizes_init(void)
 	unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
 
 #ifdef CONFIG_ZONE_DMA32
-	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, max_low_pfn));
+	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G,
+			(unsigned long) PFN_PHYS(max_low_pfn)));
 #endif
 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;