@@ -413,12 +413,6 @@ On error, \-1 is returned and
.I errno
is set to indicate the error.
Possible errors include:
-.\" FIXME Is the following error list correct?
-.\"
-.TP
-.B EBUSY
-A mapping in the specified range is registered with another
-userfaultfd object.
.TP
.B EFAULT
.I argp
@@ -433,21 +427,32 @@ field; or the
field was zero.
.TP
.B EINVAL
-There is no mapping in the specified address range.
-.TP
-.B EINVAL
+The specified address range was invalid.
+More specifically,
+no mapping exists in the given range,
+or the mapping that exists there is invalid
+(e.g. unsupported type of memory),
+or the range values (
.I range.start
or
.I range.len
-is not a multiple of the system page size; or,
+) are not multiples of the relevant page size,
+or
.I range.len
-is zero; or these fields are otherwise invalid.
+is zero.
.TP
-.B EINVAL
-There as an incompatible mapping in the specified address range.
-.\" Mike Rapoport:
-.\" ENOMEM if the process is exiting and the
-.\" mm_struct has gone by the time userfault grabs it.
+.B ENOMEM
+The process is exiting,
+and its address space has already been torn down
+when userfaultfd attempts to reference it.
+.TP
+.B EPERM
+The userfaultfd would allow writing to a file backing the mapping,
+but the calling process lacks such write permissions.
+.TP
+.B EBUSY
+A mapping in the specified range is registered with another
+userfaultfd object.
.SS UFFDIO_UNREGISTER
(Since Linux 4.3.)
Unregister a memory address range from userfaultfd.
The list of error codes in the man page was out of date with respect to the current state of the kernel. Some errors were partially / incorrectly described. Update the error code listing, so it matches the current state of the kernel, and correctly describes all the errors. Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> --- man2/ioctl_userfaultfd.2 | 37 +++++++++++++++++++++---------------- 1 file changed, 21 insertions(+), 16 deletions(-)