getrlimit.2, mmap.2, malloc.3: RLIMIT_DATA affects mmap (2) since Linux 4.7

Starting with Linux kernel 4.5 and 84638335900f1995
(mm: rework virtual memory accounting) RLIMIT_DATA affects
mmap(2).  With d977d56ce5b3e88 (mm: warn about VmData over
RLIMIT_DATA) only warnings are emmitted when going over the
specified RLIMIT_DATA in 4.5.

As of 4.7 and f4fcd55841fc9 (mm: enable RLIMIT_DATA by default
with workaround for valgrind) going over RLIMIT_DATA through
mmap(2) is forbidden.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

man2/getrlimit.2

@@ -182,9 +182,14 @@ of the process's data segment (initialized data,
 uninitialized data, and heap).
 The limit is specified in bytes, and is rounded down to the system page size.
 This limit affects calls to
-.BR brk (2)
-and
+.BR brk (2),
 .BR sbrk (2),
+and as of Linux 4.7 also
+.BR mmap (2),
+.\" commits 84638335900f1995495838fe1bd4870c43ec1f67
+.\" ("mm: rework virtual memory accounting"),
+.\" f4fcd55841fc9e46daac553b39361572453c2b88
+.\" (mm: enable RLIMIT_DATA by default with workaround for valgrind).
 which fail with the error
 .B ENOMEM
 upon encountering the soft limit of this resource.

man2/mmap.2

@@ -493,6 +493,14 @@ when unmapping a region in the middle of an existing mapping,
 since this results in two smaller mappings on either side of
 the region being unmapped.
 .TP
+.B ENOMEM
+(since Linux 4.7)
+The process's
+.B RLIMIT_DATA
+limit, described in
+.BR getrlimit (2),
+would have been exceeded.
+.TP
 .B EOVERFLOW
 On 32-bit architecture together with the large file extension
 (i.e., using 64-bit

man3/malloc.3

@@ -292,7 +292,7 @@ Allocations performed using
 .BR mmap (2)
 are unaffected by the
 .B RLIMIT_DATA
-resource limit (see
+resource limit only prior to Linux kernel 4.7 (see
 .BR getrlimit (2)).
 .PP
 To avoid corruption in multithreaded applications,