Commit 37cb0aab authored by Yang Shi's avatar Yang Shi Committed by Catalin Marinas
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arm64: mm: make linear mapping permission update more robust for patial range 



The commit fcf8dda8 ("arm64: pageattr: Explicitly bail out when changing
permissions for vmalloc_huge mappings") made permission update for
partial range more robust. But the linear mapping permission update
still assumes update the whole range by iterating from the first page
all the way to the last page of the area.

Make it more robust by updating the linear mapping permission from the
page mapped by start address, and update the number of numpages.

Reviewed-by: default avatarRyan Roberts <ryan.roberts@arm.com>
Reviewed-by: default avatarDev Jain <dev.jain@arm.com>
Signed-off-by: default avatarYang Shi <yang@os.amperecomputing.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent c320dbb7

arch/arm64/mm/pageattr.c

+3 −3
Original line number Diff line number Diff line
@@ -148,7 +148,6 @@ static int change_memory_common(unsigned long addr, int numpages, 
	unsigned long size = PAGE_SIZE * numpages;

	unsigned long end = start + size;

	struct vm_struct *area;

	int i;



	if (!PAGE_ALIGNED(addr)) {

		start &= PAGE_MASK;
@@ -184,8 +183,9 @@ static int change_memory_common(unsigned long addr, int numpages, 
	 */

	if (rodata_full && (pgprot_val(set_mask) == PTE_RDONLY ||

			    pgprot_val(clear_mask) == PTE_RDONLY)) {

		for (i = 0; i < area->nr_pages; i++) {

			__change_memory_common((u64)page_address(area->pages[i]),

		unsigned long idx = (start - (unsigned long)area->addr) >> PAGE_SHIFT;

		for (; numpages; idx++, numpages--) {

			__change_memory_common((u64)page_address(area->pages[idx]),

					       PAGE_SIZE, set_mask, clear_mask);

		}

	}