[merged] mm-memcg-fix-device-private-memcg-accounting.patch removed from -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: mm/memcg: fix device private memcg accounting
has been removed from the -mm tree.  Its filename was
     mm-memcg-fix-device-private-memcg-accounting.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Ralph Campbell <rcampbell@nvidia.com>
Subject: mm/memcg: fix device private memcg accounting

The code in mc_handle_swap_pte() checks for non_swap_entry() and returns
NULL before checking is_device_private_entry() so device private pages are
never handled.  Fix this by checking for non_swap_entry() after handling
device private swap PTEs.

I assume the memory cgroup accounting would be off somehow when moving
a process to another memory cgroup.  Currently, the device private page
is charged like a normal anonymous page when allocated and is uncharged
when the page is freed so I think that path is OK.

Link: https://lkml.kernel.org/r/20201009215952.2726-1-rcampbell@nvidia.com
xFixes: c733a82874a7 ("mm/memcontrol: support MEMORY_DEVICE_PRIVATE")
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/mm/memcontrol.c~mm-memcg-fix-device-private-memcg-accounting
+++ a/mm/memcontrol.c
@@ -5516,7 +5516,7 @@ static struct page *mc_handle_swap_pte(s
 	struct page *page = NULL;
 	swp_entry_t ent = pte_to_swp_entry(ptent);
 
-	if (!(mc.flags & MOVE_ANON) || non_swap_entry(ent))
+	if (!(mc.flags & MOVE_ANON))
 		return NULL;
 
 	/*
@@ -5535,6 +5535,9 @@ static struct page *mc_handle_swap_pte(s
 		return page;
 	}
 
+	if (non_swap_entry(ent))
+		return NULL;
+
 	/*
 	 * Because lookup_swap_cache() updates some statistics counter,
 	 * we call find_get_page() with swapper_space directly.
_

Patches currently in -mm which might be from rcampbell@nvidia.com are