[src/trunk]: src/sys/dev do not attach nvme ld as randomness source - device ...

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

details:   https://anonhg.NetBSD.org/src/rev/704080bc6d99
branches:  trunk
changeset: 353292:704080bc6d99
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Thu Apr 27 17:07:22 2017 +0000

description:
do not attach nvme ld as randomness source - device is too fast, it overwhelms
the rndq handling code, and causes system crashes; gathering rnd there is
also bad idea from performance perspective

diffstat:

 sys/dev/dksubr.c     |  21 +++++++++++++--------
 sys/dev/dkvar.h      |   3 ++-
 sys/dev/ic/ld_nvme.c |   6 +++---
 sys/dev/ld.c         |   7 +++++--
 sys/dev/ldvar.h      |   3 ++-
 5 files changed, 25 insertions(+), 15 deletions(-)

diffs (143 lines):

diff -r 8dacf791b7d0 -r 704080bc6d99 sys/dev/dksubr.c
--- a/sys/dev/dksubr.c  Thu Apr 27 16:52:22 2017 +0000
+++ b/sys/dev/dksubr.c  Thu Apr 27 17:07:22 2017 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: dksubr.c,v 1.96 2017/03/05 23:07:12 mlelstv Exp $ */
+/* $NetBSD: dksubr.c,v 1.97 2017/04/27 17:07:22 jdolecek Exp $ */
 
 /*-
  * Copyright (c) 1996, 1997, 1998, 1999, 2002, 2008 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dksubr.c,v 1.96 2017/03/05 23:07:12 mlelstv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dksubr.c,v 1.97 2017/04/27 17:07:22 jdolecek Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -102,16 +102,20 @@
        dksc->sc_flags |= DKF_WARNLABEL | DKF_LABELSANITY;
 #endif
 
-       /* Attach the device into the rnd source list. */
-       rnd_attach_source(&dksc->sc_rnd_source, dksc->sc_xname,
-           RND_TYPE_DISK, RND_FLAG_DEFAULT);
+       if ((dksc->sc_flags & DKF_NO_RND) == 0) {
+               /* Attach the device into the rnd source list. */
+               rnd_attach_source(&dksc->sc_rnd_source, dksc->sc_xname,
+                   RND_TYPE_DISK, RND_FLAG_DEFAULT);
+       }
 }
 
 void
 dk_detach(struct dk_softc *dksc)
 {
-       /* Unhook the entropy source. */
-       rnd_detach_source(&dksc->sc_rnd_source);
+       if ((dksc->sc_flags & DKF_NO_RND) == 0) {
+               /* Unhook the entropy source. */
+               rnd_detach_source(&dksc->sc_rnd_source);
+       }
 
        dksc->sc_flags &= ~DKF_READYFORDUMP;
        mutex_destroy(&dksc->sc_iolock);
@@ -458,7 +462,8 @@
        if (lock)
                mutex_exit(&dksc->sc_iolock);
 
-       rnd_add_uint32(&dksc->sc_rnd_source, bp->b_rawblkno);
+       if ((dksc->sc_flags & DKF_NO_RND) == 0)
+               rnd_add_uint32(&dksc->sc_rnd_source, bp->b_rawblkno);
 
        biodone(bp);
 }
diff -r 8dacf791b7d0 -r 704080bc6d99 sys/dev/dkvar.h
--- a/sys/dev/dkvar.h   Thu Apr 27 16:52:22 2017 +0000
+++ b/sys/dev/dkvar.h   Thu Apr 27 17:07:22 2017 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: dkvar.h,v 1.28 2016/12/22 13:42:14 mlelstv Exp $ */
+/* $NetBSD: dkvar.h,v 1.29 2017/04/27 17:07:22 jdolecek Exp $ */
 
 /*-
  * Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -68,6 +68,7 @@
 #define DKF_KLABEL      0x00400000 /* keep label on close */
 #define DKF_VLABEL      0x00800000 /* label is valid */
 #define DKF_SLEEP       0x80000000 /* dk_start/dk_done may sleep */
+#define DKF_NO_RND     0x01000000 /* do not attach as rnd source */
 
 /* Mask of flags that dksubr.c understands, other flags are fair game */
 #define DK_FLAGMASK    0xffff0000
diff -r 8dacf791b7d0 -r 704080bc6d99 sys/dev/ic/ld_nvme.c
--- a/sys/dev/ic/ld_nvme.c      Thu Apr 27 16:52:22 2017 +0000
+++ b/sys/dev/ic/ld_nvme.c      Thu Apr 27 17:07:22 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ld_nvme.c,v 1.15 2017/04/05 20:15:49 jdolecek Exp $    */
+/*     $NetBSD: ld_nvme.c,v 1.16 2017/04/27 17:07:22 jdolecek Exp $    */
 
 /*-
  * Copyright (C) 2016 NONAKA Kimihiro <nonaka%netbsd.org@localhost>
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ld_nvme.c,v 1.15 2017/04/05 20:15:49 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ld_nvme.c,v 1.16 2017/04/27 17:07:22 jdolecek Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -128,7 +128,7 @@
        ld->sc_start = ld_nvme_start;
        ld->sc_dump = ld_nvme_dump;
        ld->sc_ioctl = ld_nvme_ioctl;
-       ld->sc_flags = LDF_ENABLED;
+       ld->sc_flags = LDF_ENABLED | LDF_NO_RND;
        ldattach(ld, "fcfs");
 }
 
diff -r 8dacf791b7d0 -r 704080bc6d99 sys/dev/ld.c
--- a/sys/dev/ld.c      Thu Apr 27 16:52:22 2017 +0000
+++ b/sys/dev/ld.c      Thu Apr 27 17:07:22 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ld.c,v 1.100 2017/02/27 21:32:33 jdolecek Exp $        */
+/*     $NetBSD: ld.c,v 1.101 2017/04/27 17:07:22 jdolecek Exp $        */
 
 /*-
  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ld.c,v 1.100 2017/02/27 21:32:33 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ld.c,v 1.101 2017/04/27 17:07:22 jdolecek Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -149,6 +149,9 @@
 
        sc->sc_disksize512 = sc->sc_secperunit * sc->sc_secsize / DEV_BSIZE;
 
+       if (sc->sc_flags & LDF_NO_RND)
+               dksc->sc_flags |= DKF_NO_RND;
+
        /* Attach dk and disk subsystems */
        dk_attach(dksc);
        disk_attach(&dksc->sc_dkdev);
diff -r 8dacf791b7d0 -r 704080bc6d99 sys/dev/ldvar.h
--- a/sys/dev/ldvar.h   Thu Apr 27 16:52:22 2017 +0000
+++ b/sys/dev/ldvar.h   Thu Apr 27 17:07:22 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ldvar.h,v 1.29 2017/02/27 21:32:33 jdolecek Exp $      */
+/*     $NetBSD: ldvar.h,v 1.30 2017/04/27 17:07:22 jdolecek Exp $      */
 
 /*-
  * Copyright (c) 2000 The NetBSD Foundation, Inc.
@@ -67,6 +67,7 @@
 /* sc_flags */
 #define        LDF_ENABLED     0x001           /* device enabled */
 #define        LDF_DRAIN       0x020           /* maxqueuecnt has changed; drain */
+#define        LDF_NO_RND      0x040           /* do not attach rnd source */
 
 int    ldadjqparam(struct ld_softc *, int);
 void   ldattach(struct ld_softc *, const char *);