From owner-freebsd-commit  Mon Oct 30 09:02:21 1995
Return-Path: owner-commit
Received: (from root@localhost)
          by freefall.freebsd.org (8.6.12/8.6.6) id JAA01016
          for freebsd-commit-outgoing; Mon, 30 Oct 1995 09:02:21 -0800
Received: (from root@localhost)
          by freefall.freebsd.org (8.6.12/8.6.6) id JAA00995
          for cvs-all-outgoing; Mon, 30 Oct 1995 09:02:01 -0800
Received: (from root@localhost)
          by freefall.freebsd.org (8.6.12/8.6.6) id JAA00981
          for cvs-sys-outgoing; Mon, 30 Oct 1995 09:01:53 -0800
Received: (from bde@localhost)
          by freefall.freebsd.org (8.6.12/8.6.6) id JAA00966
          ; Mon, 30 Oct 1995 09:01:43 -0800
Date: Mon, 30 Oct 1995 09:01:43 -0800
From: Bruce Evans <bde>
Message-Id: <199510301701.JAA00966@freefall.freebsd.org>
To: CVS-commiters, cvs-sys
Subject: cvs commit: src/sys/i386/include spl.h
Sender: owner-commit@FreeBSD.org
Precedence: bulk

bde         95/10/30 09:01:41

  Modified:    sys/i386/include  spl.h
  Log:
  Mask netisrs during softtty isrs.  This may fix PR 798.  SLIP and PPP
  line discipline interrupt handlers more or less expect to be called at
  spltty() == splimp(), although they have internal splimp()s that are
  bogus if this expectation is satisfied.  They are called at splsoftty()
  from many tty drivers, so they were not protected from being reentered
  from their own netisrs.  They certainly don't expect that but are
  apparently remarkably robust if it occurs.  The problem in PR 798 seems
  to be caused by pppstart() being reentered and finishing off the output
  in progress by following the (stale) sc->sc_outm pointer.  Then the
  original pppstart() finds garbage in m2 after MFREE(m, m2).  slstart()
  doesn't have internal state like sc_outm so reentry of it probably only
  causes out of order and dropped packets.