Firmware and hypervisor drivers can donate system heap memory to their respective firmware/hypervisor entities. Those drivers should unmap the pages from the kernel's logical map before doing so. Export can_set_direct_map, set_direct_map_invalid_noflush, and set_direct_map_default_noflush. Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx> --- arch/arm64/mm/pageattr.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 924843f1f661b..a9bd84588c98a 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -32,6 +32,7 @@ bool can_set_direct_map(void) return rodata_full || debug_pagealloc_enabled() || arm64_kfence_can_set_direct_map(); } +EXPORT_SYMBOL_GPL(can_set_direct_map); static int change_page_range(pte_t *ptep, unsigned long addr, void *data) { @@ -176,6 +177,7 @@ int set_direct_map_invalid_noflush(struct page *page) (unsigned long)page_address(page), PAGE_SIZE, change_page_range, &data); } +EXPORT_SYMBOL_GPL(set_direct_map_invalid_noflush); int set_direct_map_default_noflush(struct page *page) { @@ -191,6 +193,7 @@ int set_direct_map_default_noflush(struct page *page) (unsigned long)page_address(page), PAGE_SIZE, change_page_range, &data); } +EXPORT_SYMBOL_GPL(set_direct_map_default_noflush); #ifdef CONFIG_DEBUG_PAGEALLOC void __kernel_map_pages(struct page *page, int numpages, int enable) -- 2.34.1