Merge tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Support for the new "riscv,isa-extensions" and "riscv,isa-base"
   device tree interfaces for probing extensions

 - Support for userspace access to the performance counters

 - Support for more instructions in kprobes

 - Crash kernels can be allocated above 4GiB

 - Support for KCFI

 - Support for ELFs in !MMU configurations

 - ARCH_KMALLOC_MINALIGN has been reduced to 8

 - mmap() defaults to sv48-sized addresses, with longer addresses hidden
   behind a hint (similar to Arm and Intel)

 - Also various fixes and cleanups

* tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits)
  lib/Kconfig.debug: Restrict DEBUG_INFO_SPLIT for RISC-V
  riscv: support PREEMPT_DYNAMIC with static keys
  riscv: Move create_tmp_mapping() to init sections
  riscv: Mark KASAN tmp* page tables variables as static
  riscv: mm: use bitmap_zero() API
  riscv: enable DEBUG_FORCE_FUNCTION_ALIGN_64B
  riscv: remove redundant mv instructions
  RISC-V: mm: Document mmap changes
  RISC-V: mm: Update pgtable comment documentation
  RISC-V: mm: Add tests for RISC-V mm
  RISC-V: mm: Restrict address space for sv39,sv48,sv57
  riscv: enable DMA_BOUNCE_UNALIGNED_KMALLOC for !dma_coherent
  riscv: allow kmalloc() caches aligned to the smallest value
  riscv: support the elf-fdpic binfmt loader
  binfmt_elf_fdpic: support 64-bit systems
  riscv: Allow CONFIG_CFI_CLANG to be selected
  riscv/purgatory: Disable CFI
  riscv: Add CFI error handling
  riscv: Add ftrace_stub_graph
  riscv: Add types to indirectly called assembly functions
  ...

4 files changed, 99 insertions, 12 deletions

diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
index 12e22e7330e7..217fd4de6134 100644
--- a/arch/riscv/mm/context.c
+++ b/arch/riscv/mm/context.c
@@ -67,7 +67,7 @@ static void __flush_context(void)
 	lockdep_assert_held(&context_lock);
 
 	/* Update the list of reserved ASIDs and the ASID bitmap. */
-	bitmap_clear(context_asid_map, 0, num_asids);
+	bitmap_zero(context_asid_map, num_asids);
 
 	/* Mark already active ASIDs as used */
 	for_each_possible_cpu(i) {
diff --git a/arch/riscv/mm/dma-noncoherent.c b/arch/riscv/mm/dma-noncoherent.c
index d51a75864e53..7270b4d8c05b 100644
--- a/arch/riscv/mm/dma-noncoherent.c
+++ b/arch/riscv/mm/dma-noncoherent.c
@@ -11,6 +11,8 @@
 #include <asm/cacheflush.h>
 
 static bool noncoherent_supported __ro_after_init;
+int dma_cache_alignment __ro_after_init = ARCH_DMA_MINALIGN;
+EXPORT_SYMBOL_GPL(dma_cache_alignment);
 
 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
 			      enum dma_data_direction dir)
@@ -78,3 +80,9 @@ void riscv_noncoherent_supported(void)
 	     "Non-coherent DMA support enabled without a block size\n");
 	noncoherent_supported = true;
 }
+
+void __init riscv_set_dma_cache_alignment(void)
+{
+	if (!noncoherent_supported)
+		dma_cache_alignment = 1;
+}
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index c07ff3e2c90a..943c18d6ef4d 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -1299,6 +1299,28 @@ static inline void setup_vm_final(void)
 }
 #endif /* CONFIG_MMU */
 
+/* Reserve 128M low memory by default for swiotlb buffer */
+#define DEFAULT_CRASH_KERNEL_LOW_SIZE	(128UL << 20)
+
+static int __init reserve_crashkernel_low(unsigned long long low_size)
+{
+	unsigned long long low_base;
+
+	low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit);
+	if (!low_base) {
+		pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);
+		return -ENOMEM;
+	}
+
+	pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
+		low_base, low_base + low_size, low_size >> 20);
+
+	crashk_low_res.start = low_base;
+	crashk_low_res.end = low_base + low_size - 1;
+
+	return 0;
+}
+
 /*
  * reserve_crashkernel() - reserves memory for crash kernel
  *
@@ -1310,8 +1332,12 @@ static void __init reserve_crashkernel(void)
 {
 	unsigned long long crash_base = 0;
 	unsigned long long crash_size = 0;
+	unsigned long long crash_low_size = 0;
 	unsigned long search_start = memblock_start_of_DRAM();
-	unsigned long search_end = memblock_end_of_DRAM();
+	unsigned long search_end = (unsigned long)dma32_phys_limit;
+	char *cmdline = boot_command_line;
+	bool fixed_base = false;
+	bool high = false;
 
 	int ret = 0;
 
@@ -1327,14 +1353,36 @@ static void __init reserve_crashkernel(void)
 		return;
 	}
 
-	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
+	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
 				&crash_size, &crash_base);
-	if (ret || !crash_size)
+	if (ret == -ENOENT) {
+		/* Fallback to crashkernel=X,[high,low] */
+		ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base);
+		if (ret || !crash_size)
+			return;
+
+		/*
+		 * crashkernel=Y,low is valid only when crashkernel=X,high
+		 * is passed.
+		 */
+		ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base);
+		if (ret == -ENOENT)
+			crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+		else if (ret)
+			return;
+
+		search_start = (unsigned long)dma32_phys_limit;
+		search_end = memblock_end_of_DRAM();
+		high = true;
+	} else if (ret || !crash_size) {
+		/* Invalid argument value specified */
 		return;
+	}
 
 	crash_size = PAGE_ALIGN(crash_size);
 
 	if (crash_base) {
+		fixed_base = true;
 		search_start = crash_base;
 		search_end = crash_base + crash_size;
 	}
@@ -1347,12 +1395,37 @@ static void __init reserve_crashkernel(void)
 	 * swiotlb can work on the crash kernel.
 	 */
 	crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
-					       search_start,
-					       min(search_end, (unsigned long)(SZ_4G - 1)));
+					       search_start, search_end);
 	if (crash_base == 0) {
-		/* Try again without restricting region to 32bit addressible memory */
+		/*
+		 * For crashkernel=size[KMG]@offset[KMG], print out failure
+		 * message if can't reserve the specified region.
+		 */
+		if (fixed_base) {
+			pr_warn("crashkernel: allocating failed with given size@offset\n");
+			return;
+		}
+
+		if (high) {
+			/*
+			 * For crashkernel=size[KMG],high, if the first attempt was
+			 * for high memory, fall back to low memory.
+			 */
+			search_start = memblock_start_of_DRAM();
+			search_end = (unsigned long)dma32_phys_limit;
+		} else {
+			/*
+			 * For crashkernel=size[KMG], if the first attempt was for
+			 * low memory, fall back to high memory, the minimum required
+			 * low memory will be reserved later.
+			 */
+			search_start = (unsigned long)dma32_phys_limit;
+			search_end = memblock_end_of_DRAM();
+			crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+		}
+
 		crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
-						search_start, search_end);
+						       search_start, search_end);
 		if (crash_base == 0) {
 			pr_warn("crashkernel: couldn't allocate %lldKB\n",
 				crash_size >> 10);
@@ -1360,6 +1433,12 @@ static void __init reserve_crashkernel(void)
 		}
 	}
 
+	if ((crash_base >= dma32_phys_limit) && crash_low_size &&
+	     reserve_crashkernel_low(crash_low_size)) {
+		memblock_phys_free(crash_base, crash_size);
+		return;
+	}
+
 	pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
 		crash_base, crash_base + crash_size, crash_size >> 20);
 
diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c
index a01bc15dce24..5e39dcf23fdb 100644
--- a/arch/riscv/mm/kasan_init.c
+++ b/arch/riscv/mm/kasan_init.c
@@ -22,9 +22,9 @@
  * region is not and then we have to go down to the PUD level.
  */
 
-pgd_t tmp_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
-p4d_t tmp_p4d[PTRS_PER_P4D] __page_aligned_bss;
-pud_t tmp_pud[PTRS_PER_PUD] __page_aligned_bss;
+static pgd_t tmp_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+static p4d_t tmp_p4d[PTRS_PER_P4D] __page_aligned_bss;
+static pud_t tmp_pud[PTRS_PER_PUD] __page_aligned_bss;
 
 static void __init kasan_populate_pte(pmd_t *pmd, unsigned long vaddr, unsigned long end)
 {
@@ -438,7 +438,7 @@ static void __init kasan_shallow_populate(void *start, void *end)
 	kasan_shallow_populate_pgd(vaddr, vend);
 }
 
-static void create_tmp_mapping(void)
+static void __init create_tmp_mapping(void)
 {
 	void *ptr;
 	p4d_t *base_p4d;