The patch titled
Subject: include/linux/swapops.h: correct guards for non_swap_entry()
has been removed from the -mm tree. Its filename was
mm-correct-guards-for-non_swap_entry.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Steven Price <steven.price@xxxxxxx>
Subject: include/linux/swapops.h: correct guards for non_swap_entry()
If CONFIG_DEVICE_PRIVATE is defined, but neither CONFIG_MEMORY_FAILURE nor
CONFIG_MIGRATION, then non_swap_entry() will return 0, meaning that the
condition (non_swap_entry(entry) && is_device_private_entry(entry)) in
zap_pte_range() will never be true even if the entry is a device private
one.
Equally any other code depending on non_swap_entry() will not function as
expected.
I originally spotted this just by looking at the code, I haven't actually
observed any problems.
Looking a bit more closely it appears that actually this situation
(currently at least) cannot occur:
DEVICE_PRIVATE depends on ZONE_DEVICE
ZONE_DEVICE depends on MEMORY_HOTREMOVE
MEMORY_HOTREMOVE depends on MIGRATION
Link: http://lkml.kernel.org/r/20200305130550.22693-1-steven.price@xxxxxxx
Fixes: 5042db43cc26 ("mm/ZONE_DEVICE: new type of ZONE_DEVICE for unaddressable memory")
Signed-off-by: Steven Price <steven.price@xxxxxxx>
Cc: Jérôme Glisse <jglisse@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/swapops.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/include/linux/swapops.h~mm-correct-guards-for-non_swap_entry
+++ a/include/linux/swapops.h
@@ -350,7 +350,8 @@ static inline void num_poisoned_pages_in
}
#endif
-#if defined(CONFIG_MEMORY_FAILURE) || defined(CONFIG_MIGRATION)
+#if defined(CONFIG_MEMORY_FAILURE) || defined(CONFIG_MIGRATION) || \
+ defined(CONFIG_DEVICE_PRIVATE)
static inline int non_swap_entry(swp_entry_t entry)
{
return swp_type(entry) >= MAX_SWAPFILES;
_
Patches currently in -mm which might be from steven.price@xxxxxxx are
