This seems to miss hitting the correct mailing list: mtk.manpages@xxxxxxxxx linux-man@xxxxxxxxxxxxxxx Christian On Fri, Feb 07, 2020 at 12:21:24PM -0800, Brian Geffon wrote: > Signed-off-by: Brian Geffon <bgeffon@xxxxxxxxxx> > --- > man2/mremap.2 | 27 ++++++++++++++++++++++++++- > 1 file changed, 26 insertions(+), 1 deletion(-) > > diff --git a/man2/mremap.2 b/man2/mremap.2 > index d73fb64fa..c660a45be 100644 > --- a/man2/mremap.2 > +++ b/man2/mremap.2 > @@ -26,7 +26,8 @@ > .\" 1996-04-12 Tom Bjorkholm <tomb@xxxxxxxxx> > .\" Update for Linux 1.3.87 and later > .\" 2005-10-11 mtk: Added NOTES for MREMAP_FIXED; revised EINVAL text. > -.\" > +.\" 2020-02-05 Brian Geffon <bgeffon@xxxxxxxxxx> > +.\" Update for MREMAP_DONTUNMAP. > .TH MREMAP 2 2019-03-06 "Linux" "Linux Programmer's Manual" > .SH NAME > mremap \- remap a virtual memory address > @@ -129,6 +130,13 @@ If > is specified, then > .B MREMAP_MAYMOVE > must also be specified. > +.TP > +.BR MREMAP_DONTUNMAP " (since Linux ?.?)" > +This flag which must be used in conjuction with > +.B MREMAP_MAYMOVE > +remaps a mapping to a new address and it does not unmap the mapping at \fIold_address\fP. This flag can only be used with private anonymous mappings. Any access to the range specified at \fIold_address\fP after completion will result in a page fault. If a > +.BR userfaultfd (2) > +was registered on the mapping specified by \fIold_address\fP it will continue to watch that mapping for faults. > .PP > If the memory segment specified by > .I old_address > @@ -176,6 +184,8 @@ a value other than > .B MREMAP_MAYMOVE > or > .B MREMAP_FIXED > +or > +.B MREMAP_DONTUNMAP > was specified in > .IR flags ; > .IP * > @@ -197,9 +207,14 @@ and > .IR old_size ; > .IP * > .B MREMAP_FIXED > +or > +.B MREMAP_DONTUNMAP > was specified without also specifying > .BR MREMAP_MAYMOVE ; > .IP * > +.B MREMAP_DONTUNMAP > +was specified with an \fIold_address\fP that was not private anonymous; > +.IP * > \fIold_size\fP was zero and \fIold_address\fP does not refer to a > shareable mapping (but see BUGS); > .IP * > @@ -209,10 +224,20 @@ flag was not specified. > .RE > .TP > .B ENOMEM > +Not enough memory was available to complete the operation. > +Possible causes are: > +.RS > +.IP * 3 > The memory area cannot be expanded at the current virtual address, and the > .B MREMAP_MAYMOVE > flag is not set in \fIflags\fP. > Or, there is not enough (virtual) memory available. > +.IP * > +.B MREMAP_DONTUNMAP > +was used without > +.B MREMAP_FIXED > +causing a new mapping to be created that would exceed the virtual memory available or it would exceed the maximum number of allowed mappings. > +.RE > .SH CONFORMING TO > This call is Linux-specific, and should not be used in programs > intended to be portable. > -- > 2.25.0.341.g760bfbb309-goog >