Commit 62072526 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'mm-hotfixes-stable-2022-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 

Pull misc fixes from Andrew Morton:
 "Two hotfixes, both cc:stable"

* tag 'mm-hotfixes-stable-2022-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm/hmm: fault non-owner device private entries
  page_alloc: fix invalid watermark check on a negative value
parents 8a91f86f 8a295dbb

mm/hmm.c

+8 −11
Original line number Diff line number Diff line
@@ -212,14 +212,6 @@ int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr, 
		unsigned long end, unsigned long hmm_pfns[], pmd_t pmd);

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */



static inline bool hmm_is_device_private_entry(struct hmm_range *range,

		swp_entry_t entry)

{

	return is_device_private_entry(entry) &&

		pfn_swap_entry_to_page(entry)->pgmap->owner ==

		range->dev_private_owner;

}



static inline unsigned long pte_to_hmm_pfn_flags(struct hmm_range *range,

						 pte_t pte)

{
@@ -252,10 +244,12 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, 
		swp_entry_t entry = pte_to_swp_entry(pte);



		/*

		 * Never fault in device private pages, but just report

		 * the PFN even if not present.

		 * Don't fault in device private pages owned by the caller,

		 * just report the PFN.

		 */

		if (hmm_is_device_private_entry(range, entry)) {

		if (is_device_private_entry(entry) &&

		    pfn_swap_entry_to_page(entry)->pgmap->owner ==

		    range->dev_private_owner) {

			cpu_flags = HMM_PFN_VALID;

			if (is_writable_device_private_entry(entry))

				cpu_flags |= HMM_PFN_WRITE;
@@ -273,6 +267,9 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, 
		if (!non_swap_entry(entry))

			goto fault;



		if (is_device_private_entry(entry))

			goto fault;



		if (is_device_exclusive_entry(entry))

			goto fault;

mm/page_alloc.c

+8 −4
Original line number Diff line number Diff line
@@ -3968,11 +3968,15 @@ static inline bool zone_watermark_fast(struct zone *z, unsigned int order, 
	 * need to be calculated.

	 */

	if (!order) {

		long fast_free;

		long usable_free;

		long reserved;



		fast_free = free_pages;

		fast_free -= __zone_watermark_unusable_free(z, 0, alloc_flags);

		if (fast_free > mark + z->lowmem_reserve[highest_zoneidx])

		usable_free = free_pages;

		reserved = __zone_watermark_unusable_free(z, 0, alloc_flags);



		/* reserved may over estimate high-atomic reserves. */

		usable_free -= min(usable_free, reserved);

		if (usable_free > mark + z->lowmem_reserve[highest_zoneidx])

			return true;

	}