Merge "mm/memblock: fix a race between search and remove" (91ddce1b) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/base/dma-removed.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -184,8 +184,10 @@ static void removed_region_fixup(struct removed_region *dma_mem, int index)
		return;

		/* carve-out */
		memblock_region_resize_late_begin();
		memblock_free(dma_mem->base, dma_mem->nr_pages * PAGE_SIZE);
		memblock_remove(dma_mem->base, index * PAGE_SIZE);
		memblock_region_resize_late_end();

		/* clear page-mappings */
		base_pfn = dma_mem->base >> PAGE_SHIFT;

include/linux/memblock.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -75,6 +75,8 @@ int memblock_reserve(phys_addr_t base, phys_addr_t size);
		void memblock_trim_memory(phys_addr_t align);
		int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size);
		int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
		void memblock_region_resize_late_begin(void);
		void memblock_region_resize_late_end(void);

		/* Low level functions */
		int memblock_add_range(struct memblock_type *type,

mm/memblock.c

+43 −1

Original line number	Diff line number	Diff line
		@@ -19,6 +19,8 @@
		#include <linux/debugfs.h>
		#include <linux/seq_file.h>
		#include <linux/memblock.h>
		#include <linux/preempt.h>
		#include <linux/seqlock.h>

		#include <asm-generic/sections.h>
		#include <linux/io.h>
		@@ -31,6 +33,7 @@ static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIO
		static struct memblock_region memblock_physmem_init_regions[INIT_PHYSMEM_REGIONS] __initdata_memblock;
		#endif

		static seqcount_t memblock_seq;
		struct memblock memblock __initdata_memblock = {
		.memory.regions = memblock_memory_init_regions,
		.memory.cnt = 1, /* empty dummy entry */
		@@ -1375,7 +1378,7 @@ void __init memblock_enforce_memory_limit(phys_addr_t limit)
		(phys_addr_t)ULLONG_MAX);
		}

		static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
		static int __init_memblock __memblock_search(struct memblock_type *type, phys_addr_t addr)
		{
		unsigned int left = 0, right = type->cnt;

		@@ -1393,6 +1396,19 @@ static int __init_memblock memblock_search(struct memblock_type *type, phys_addr
		return -1;
		}

		static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
		{
		int ret;
		unsigned long seq;

		do {
		seq = raw_read_seqcount_begin(&memblock_seq);
		ret = __memblock_search(type, addr);
		} while (unlikely(read_seqcount_retry(&memblock_seq, seq)));

		return ret;
		}

		int __init memblock_is_reserved(phys_addr_t addr)
		{
		return memblock_search(&memblock.reserved, addr) != -1;
		@@ -1541,6 +1557,32 @@ void __init memblock_allow_resize(void)
		memblock_can_resize = 1;
		}

		static void __init_memblock memblock_resize_late(int begin)
		{
		static int memblock_can_resize_old;

		if (begin) {
		preempt_disable();
		memblock_can_resize_old = memblock_can_resize;
		memblock_can_resize = 0;
		raw_write_seqcount_begin(&memblock_seq);
		} else {
		raw_write_seqcount_end(&memblock_seq);
		memblock_can_resize = memblock_can_resize_old;
		preempt_enable();
		}
		}

		void __init_memblock memblock_region_resize_late_begin(void)
		{
		memblock_resize_late(1);
		}

		void __init_memblock memblock_region_resize_late_end(void)
		{
		memblock_resize_late(0);
		}

		static int __init early_memblock(char *p)
		{
		if (p && strstr(p, "debug"))