Merge tag 'v5.5-rc5' into patchwork

Linux 5.5-rc5

* tag 'v5.5-rc5': (1006 commits)
  Linux 5.5-rc5
  Documentation: riscv: add patch acceptance guidelines
  riscv: prefix IRQ_ macro names with an RV_ namespace
  clocksource: riscv: add notrace to riscv_sched_clock
  apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock
  hexagon: define ioremap_uc
  ocfs2: fix the crash due to call ocfs2_get_dlm_debug once less
  ocfs2: call journal flush to mark journal as empty after journal recovery when mount
  mm/hugetlb: defer freeing of huge pages if in non-task context
  mm/gup: fix memory leak in __gup_benchmark_ioctl
  mm/oom: fix pgtables units mismatch in Killed process message
  fs/posix_acl.c: fix kernel-doc warnings
  hexagon: work around compiler crash
  hexagon: parenthesize registers in asm predicates
  fs/namespace.c: make to_mnt_ns() static
  fs/nsfs.c: include headers for missing declarations
  fs/direct-io.c: include fs/internal.h for missing prototype
  mm: move_pages: return valid node id in status if the page is already on the target node
  memcg: account security cred as well to kmemcg
  kcov: fix struct layout for kcov_remote_arg
  ...

1 files changed, 9 insertions, 3 deletions

diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index af2b4c065a04..d0019d3395cf 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -103,13 +103,19 @@ struct inet_bind_hashbucket {
 	struct hlist_head	chain;
 };
 
-/*
- * Sockets can be hashed in established or listening table
+/* Sockets can be hashed in established or listening table.
+ * We must use different 'nulls' end-of-chain value for all hash buckets :
+ * A socket might transition from ESTABLISH to LISTEN state without
+ * RCU grace period. A lookup in ehash table needs to handle this case.
  */
+#define LISTENING_NULLS_BASE (1U << 29)
 struct inet_listen_hashbucket {
 	spinlock_t		lock;
 	unsigned int		count;
-	struct hlist_head	head;
+	union {
+		struct hlist_head	head;
+		struct hlist_nulls_head	nulls_head;
+	};
 };
 
 /* This is for listening sockets, thus all sockets which possess wildcards. */