Merge tag 'percpu-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu

Pull percpu updates from Dennis Zhou:
 "Enable percpu page allocator for RISC-V.

  There are RISC-V configurations with sparse NUMA configurations and
  small vmalloc space causing dynamic percpu allocations to fail as the
  backing chunk stride is too far apart"

* tag 'percpu-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
  riscv: Enable pcpu page first chunk allocator
  mm: Introduce flush_cache_vmap_early()

arch/arc/include/asm/cacheflush.h

@@ -40,6 +40,7 @@ void dma_cache_wback(phys_addr_t start, unsigned long sz);
 
 /* TBD: optimize this */
 #define flush_cache_vmap(start, end)		flush_cache_all()
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		flush_cache_all()
 
 #define flush_cache_dup_mm(mm)			/* called on fork (VIVT only) */

arch/arm/include/asm/cacheflush.h

@@ -340,6 +340,8 @@ static inline void flush_cache_vmap(unsigned long start, unsigned long end)
 		dsb(ishst);
 }
 
+#define flush_cache_vmap_early(start, end)	do { } while (0)
+
 static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
 {
 	if (!cache_is_vipt_nonaliasing())

arch/csky/abiv1/inc/abi/cacheflush.h

@@ -43,6 +43,7 @@ static inline void flush_anon_page(struct vm_area_struct *vma,
  */
 extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
 #define flush_cache_vmap(start, end)		cache_wbinv_all()
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		cache_wbinv_all()
 
 #define flush_icache_range(start, end)		cache_wbinv_range(start, end)

arch/csky/abiv2/inc/abi/cacheflush.h

@@ -41,6 +41,7 @@ void flush_icache_mm_range(struct mm_struct *mm,
 void flush_icache_deferred(struct mm_struct *mm);
 
 #define flush_cache_vmap(start, end)		do { } while (0)
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		do { } while (0)
 
 #define copy_to_user_page(vma, page, vaddr, dst, src, len) \

arch/m68k/include/asm/cacheflush_mm.h

@@ -191,6 +191,7 @@ extern void cache_push_v(unsigned long vaddr, int len);
 #define flush_cache_all() __flush_cache_all()
 
 #define flush_cache_vmap(start, end)		flush_cache_all()
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		flush_cache_all()
 
 static inline void flush_cache_mm(struct mm_struct *mm)

arch/mips/include/asm/cacheflush.h

@@ -97,6 +97,8 @@ static inline void flush_cache_vmap(unsigned long start, unsigned long end)
 		__flush_cache_vmap();
 }
 
+#define flush_cache_vmap_early(start, end)     do { } while (0)
+
 extern void (*__flush_cache_vunmap)(void);
 
 static inline void flush_cache_vunmap(unsigned long start, unsigned long end)

arch/nios2/include/asm/cacheflush.h

@@ -38,6 +38,7 @@ void flush_icache_pages(struct vm_area_struct *vma, struct page *page,
 #define flush_icache_pages flush_icache_pages
 
 #define flush_cache_vmap(start, end)		flush_dcache_range(start, end)
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		flush_dcache_range(start, end)
 
 extern void copy_to_user_page(struct vm_area_struct *vma, struct page *page,

arch/parisc/include/asm/cacheflush.h

@@ -41,6 +41,7 @@ void flush_kernel_vmap_range(void *vaddr, int size);
 void invalidate_kernel_vmap_range(void *vaddr, int size);
 
 #define flush_cache_vmap(start, end)		flush_cache_all()
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		flush_cache_all()
 
 void flush_dcache_folio(struct folio *folio);

arch/riscv/Kconfig

@@ -416,7 +416,9 @@ config NUMA
 	depends on SMP && MMU
 	select ARCH_SUPPORTS_NUMA_BALANCING
 	select GENERIC_ARCH_NUMA
+	select HAVE_SETUP_PER_CPU_AREA
 	select NEED_PER_CPU_EMBED_FIRST_CHUNK
+	select NEED_PER_CPU_PAGE_FIRST_CHUNK
 	select OF_NUMA
 	select USE_PERCPU_NUMA_NODE_ID
 	help

arch/riscv/include/asm/cacheflush.h

@@ -37,7 +37,8 @@ static inline void flush_dcache_page(struct page *page)
 	flush_icache_mm(vma->vm_mm, 0)
 
 #ifdef CONFIG_64BIT
-#define flush_cache_vmap(start, end)	flush_tlb_kernel_range(start, end)
+#define flush_cache_vmap(start, end)		flush_tlb_kernel_range(start, end)
+#define flush_cache_vmap_early(start, end)	local_flush_tlb_kernel_range(start, end)
 #endif
 
 #ifndef CONFIG_SMP

arch/riscv/include/asm/tlbflush.h

@@ -41,6 +41,7 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr);
 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 		     unsigned long end);
 void flush_tlb_kernel_range(unsigned long start, unsigned long end);
+void local_flush_tlb_kernel_range(unsigned long start, unsigned long end);
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
 void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start,

arch/riscv/mm/kasan_init.c

@@ -441,6 +441,14 @@ static void __init kasan_shallow_populate(void *start, void *end)
 	kasan_shallow_populate_pgd(vaddr, vend);
 }
 
+#ifdef CONFIG_KASAN_VMALLOC
+void __init kasan_populate_early_vm_area_shadow(void *start, unsigned long size)
+{
+	kasan_populate(kasan_mem_to_shadow(start),
+		       kasan_mem_to_shadow(start + size));
+}
+#endif
+
 static void __init create_tmp_mapping(void)
 {
 	void *ptr;

arch/riscv/mm/tlbflush.c

@@ -66,6 +66,11 @@ static inline void local_flush_tlb_range_asid(unsigned long start,
 		local_flush_tlb_range_threshold_asid(start, size, stride, asid);
 }
 
+void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	local_flush_tlb_range_asid(start, end, PAGE_SIZE, FLUSH_TLB_NO_ASID);
+}
+
 static void __ipi_flush_tlb_all(void *info)
 {
 	local_flush_tlb_all();

arch/sh/include/asm/cacheflush.h

@@ -90,6 +90,7 @@ extern void copy_from_user_page(struct vm_area_struct *vma,
 	unsigned long len);
 
 #define flush_cache_vmap(start, end)		local_flush_cache_all(NULL)
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		local_flush_cache_all(NULL)
 
 #define flush_dcache_mmap_lock(mapping)		do { } while (0)

arch/sparc/include/asm/cacheflush_32.h

@@ -48,6 +48,7 @@ static inline void flush_dcache_page(struct page *page)
 #define flush_dcache_mmap_unlock(mapping)	do { } while (0)
 
 #define flush_cache_vmap(start, end)		flush_cache_all()
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		flush_cache_all()
 
 /* When a context switch happens we must flush all user windows so that

arch/sparc/include/asm/cacheflush_64.h

@@ -75,6 +75,7 @@ void flush_ptrace_access(struct vm_area_struct *, struct page *,
 #define flush_dcache_mmap_unlock(mapping)	do { } while (0)
 
 #define flush_cache_vmap(start, end)		do { } while (0)
+#define flush_cache_vmap_early(start, end)	do { } while (0)
 #define flush_cache_vunmap(start, end)		do { } while (0)
 
 #endif /* !__ASSEMBLY__ */

arch/xtensa/include/asm/cacheflush.h

@@ -116,8 +116,9 @@ void flush_cache_page(struct vm_area_struct*,
 #define flush_cache_mm(mm)		flush_cache_all()
 #define flush_cache_dup_mm(mm)		flush_cache_mm(mm)
 
-#define flush_cache_vmap(start,end)	flush_cache_all()
-#define flush_cache_vunmap(start,end)	flush_cache_all()
+#define flush_cache_vmap(start,end)		flush_cache_all()
+#define flush_cache_vmap_early(start,end)	do { } while (0)
+#define flush_cache_vunmap(start,end)		flush_cache_all()
 
 void flush_dcache_folio(struct folio *folio);
 #define flush_dcache_folio flush_dcache_folio
@@ -140,6 +141,7 @@ void local_flush_cache_page(struct vm_area_struct *vma,
 #define flush_cache_dup_mm(mm)				do { } while (0)
 
 #define flush_cache_vmap(start,end)			do { } while (0)
+#define flush_cache_vmap_early(start,end)		do { } while (0)
 #define flush_cache_vunmap(start,end)			do { } while (0)
 
 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0

include/asm-generic/cacheflush.h

@@ -91,6 +91,12 @@ static inline void flush_cache_vmap(unsigned long start, unsigned long end)
 }
 #endif
 
+#ifndef flush_cache_vmap_early
+static inline void flush_cache_vmap_early(unsigned long start, unsigned long end)
+{
+}
+#endif
+
 #ifndef flush_cache_vunmap
 static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
 {

mm/percpu.c

@@ -3333,13 +3333,7 @@ int __init pcpu_page_first_chunk(size_t reserved_size, pcpu_fc_cpu_to_node_fn_t
 		if (rc < 0)
 			panic("failed to map percpu area, err=%d\n", rc);
 
-		/*
-		 * FIXME: Archs with virtual cache should flush local
-		 * cache for the linear mapping here - something
-		 * equivalent to flush_cache_vmap() on the local cpu.
-		 * flush_cache_vmap() can't be used as most supporting
-		 * data structures are not set up yet.
-		 */
+		flush_cache_vmap_early(unit_addr, unit_addr + ai->unit_size);
 
 		/* copy static data */
 		memcpy((void *)unit_addr, __per_cpu_load, ai->static_size);