[src/netbsd-8]: src/sys/kern Pull up following revision(s) (requested by maxv...

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b22bebb600c5
branches:  netbsd-8
changeset: 319249:b22bebb600c5
user:      martin <martin%NetBSD.org@localhost>
date:      Tue May 22 17:50:27 2018 +0000

description:
Pull up following revision(s) (requested by maxv in ticket #833):

        sys/kern/uipc_mbuf.c: revision 1.214

Revert my rev1.190, remove the M_READONLY check. The initial code was
correct: what is read-only is the mbuf storage, not the mbuf itself. The
storage contains the packet payload, and never has anything related to
mbufs. So it is fine to remove M_PKTHDR on mbufs that have a read-only
storage.

In fact it was kind of obvious, since several places already manually
remove M_PKTHDR without taking care of the external storage.

diffstat:

 sys/kern/uipc_mbuf.c |  9 ++-------
 1 files changed, 2 insertions(+), 7 deletions(-)

diffs (30 lines):

diff -r 9d8bbab10a8b -r b22bebb600c5 sys/kern/uipc_mbuf.c
--- a/sys/kern/uipc_mbuf.c      Tue May 22 17:43:21 2018 +0000
+++ b/sys/kern/uipc_mbuf.c      Tue May 22 17:50:27 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_mbuf.c,v 1.172.6.4 2018/05/06 09:20:43 martin Exp $       */
+/*     $NetBSD: uipc_mbuf.c,v 1.172.6.5 2018/05/22 17:50:27 martin Exp $       */
 
 /*-
  * Copyright (c) 1999, 2001 The NetBSD Foundation, Inc.
@@ -62,7 +62,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf.c,v 1.172.6.4 2018/05/06 09:20:43 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf.c,v 1.172.6.5 2018/05/22 17:50:27 martin Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_mbuftrace.h"
@@ -460,11 +460,6 @@
 {
        KASSERT(m->m_flags & M_PKTHDR);
 
-       if (M_READONLY(m)) {
-               /* Nothing we can do. */
-               return;
-       }
-
        m_tag_delete_chain(m, NULL);
        m->m_flags &= ~M_PKTHDR;
        memset(&m->m_pkthdr, 0, sizeof(m->m_pkthdr));