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authorLinus Torvalds <torvalds@linux-foundation.org>2022-07-29 21:02:35 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-07-29 21:02:35 -0700
commit620725263f4222b3c94d4ee19846835feec0ad69 (patch)
tree7d6de25a6d4a94207a1b20dad70639fd06b5a2fe
parent8a91f86f3e9e9608210166c70aaad4919018c0e7 (diff)
parent8a295dbbaf7292c582a40ce469c326f472d51f66 (diff)
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
-rw-r--r--mm/hmm.c19
-rw-r--r--mm/page_alloc.c12
2 files changed, 16 insertions, 15 deletions
diff --git a/mm/hmm.c b/mm/hmm.c
index 3fd3242c5e50..f2aa63b94d9b 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -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;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e008a3df0485..b5b14b78c4fd 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -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;
}