Unverified Commit 0e2c0901 authored by Atish Patra's avatar Atish Patra Committed by Palmer Dabbelt
Browse files

RISC-V: Acquire mmap lock before invoking walk_page_range 

As per walk_page_range documentation, mmap lock should be acquired by the
caller before invoking walk_page_range. mmap_assert_locked gets triggered
without that. The details can be found here.

http://lists.infradead.org/pipermail/linux-riscv/2020-June/010335.html



Fixes: 395a21ff(riscv: add ARCH_HAS_SET_DIRECT_MAP support)
Signed-off-by: default avatarAtish Patra <atish.patra@wdc.com>
Reviewed-by: default avatarMichel Lespinasse <walken@google.com>
Reviewed-by: default avatarZong Li <zong.li@sifive.com>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent e0d17c84

arch/riscv/mm/pageattr.c

+12 −2
Original line number Original line Diff line number Diff line
@@ -151,6 +151,7 @@ int set_memory_nx(unsigned long addr, int numpages) 




int set_direct_map_invalid_noflush(struct page *page)

int set_direct_map_invalid_noflush(struct page *page)

{

{

	int ret;

	unsigned long start = (unsigned long)page_address(page);

	unsigned long start = (unsigned long)page_address(page);

	unsigned long end = start + PAGE_SIZE;

	unsigned long end = start + PAGE_SIZE;

	struct pageattr_masks masks = {

	struct pageattr_masks masks = {
@@ -158,11 +159,16 @@ int set_direct_map_invalid_noflush(struct page *page) 
		.clear_mask = __pgprot(_PAGE_PRESENT)

		.clear_mask = __pgprot(_PAGE_PRESENT)

	};

	};





	return walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);

	mmap_read_lock(&init_mm);

	ret = walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);

	mmap_read_unlock(&init_mm);



	return ret;

}

}





int set_direct_map_default_noflush(struct page *page)

int set_direct_map_default_noflush(struct page *page)

{

{

	int ret;

	unsigned long start = (unsigned long)page_address(page);

	unsigned long start = (unsigned long)page_address(page);

	unsigned long end = start + PAGE_SIZE;

	unsigned long end = start + PAGE_SIZE;

	struct pageattr_masks masks = {

	struct pageattr_masks masks = {
@@ -170,7 +176,11 @@ int set_direct_map_default_noflush(struct page *page) 
		.clear_mask = __pgprot(0)

		.clear_mask = __pgprot(0)

	};

	};





	return walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);

	mmap_read_lock(&init_mm);

	ret = walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);

	mmap_read_unlock(&init_mm);



	return ret;

}

}





void __kernel_map_pages(struct page *page, int numpages, int enable)

void __kernel_map_pages(struct page *page, int numpages, int enable)

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