On Wed, Sep 02, 2026 at 11:47:09AM +0100, Vincent Donnefort wrote:
Add implementation for the unsafe functions __set_direct_map*(). They do not verify for can_set_direct_map() and expect the caller to do so beforehand.
Signed-off-by: Vincent Donnefort vdonnefort@google.com
diff --git a/arch/arm64/include/asm/set_memory.h b/arch/arm64/include/asm/set_memory.h index 1a37f4ef130b..080a40846bbe 100644 --- a/arch/arm64/include/asm/set_memory.h +++ b/arch/arm64/include/asm/set_memory.h @@ -16,6 +16,10 @@ int set_memory_valid(unsigned long addr, int numpages, int enable); int set_direct_map_invalid_noflush(struct page *page); int set_direct_map_default_noflush(struct page *page); +int __set_direct_map_invalid_noflush(struct page *page); +#define __set_direct_map_invalid_noflush __set_direct_map_invalid_noflush +int __set_direct_map_default_noflush(struct page *page); +#define __set_direct_map_default_noflush __set_direct_map_default_noflush int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid); bool kernel_page_present(struct page *page); diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index c59ef17eb0d0..28adab0edace 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -294,28 +294,38 @@ int set_memory_valid(unsigned long addr, int numpages, int enable) __pgprot(PTE_PRESENT_VALID_KERNEL)); } -int set_direct_map_invalid_noflush(struct page *page) +int __set_direct_map_invalid_noflush(struct page *page) { pgprot_t clear_mask = __pgprot(PTE_PRESENT_VALID_KERNEL); pgprot_t set_mask = __pgprot(PTE_PRESENT_INVALID);
- return update_range_prot((unsigned long)page_address(page),
PAGE_SIZE, set_mask, clear_mask);+}
I think these would work quite nicely if you rebase the series onto linux-next, which contains the patches that add the number of pages to these functions.
You can then keep can_set_direct_map_range() from the previous patch and call that from the set_direct_map_*_noflush() functions instead of the simple can_set_direct_map() (which is a shortcut path in the _range check anyway.
I've used that locally in my tree and it seems to be working just fine.
Thierry