add another device mapper fix

OBS-URL: https://build.opensuse.org/package/show/Virtualization/libvirt?expand=0&rev=838

53d9af1e-ignore-devmapper-open-errors.patch

@@ -0,0 +1,74 @@
+commit 53d9af1e7924757e3b5f661131dd707d7110d094
+Author: Michal Prívozník <mprivozn@redhat.com>
+Date:   Wed Aug 19 13:35:55 2020 +0200
+
+    virdevmapper: Ignore all errors when opening /dev/mapper/control
+    
+    So far, only ENOENT is ignored (to deal with kernels without
+    devmapper). However, as reported on the list, under certain
+    scenarios a different error can occur. For instance, when libvirt
+    is running inside a container which doesn't have permissions to
+    talk to the devmapper. If this is the case, then open() returns
+    -1 and sets errno=EPERM.
+    
+    Assuming that multipath devices are fairly narrow use case and
+    using them in a restricted container is even more narrow the best
+    fix seems to be to ignore all open errors BUT produce a warning
+    on failure. To avoid flooding logs with warnings on kernels
+    without devmapper the level is reduced to a plain debug message.
+    
+    Reported-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
+    Reviewed-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
+    Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
+
+Index: libvirt-6.6.0/src/util/virdevmapper.c
+===================================================================
+--- libvirt-6.6.0.orig/src/util/virdevmapper.c
++++ libvirt-6.6.0/src/util/virdevmapper.c
+@@ -35,9 +35,12 @@
+ # include "viralloc.h"
+ # include "virstring.h"
+ # include "virfile.h"
++# include "virlog.h"
+ 
+ # define VIR_FROM_THIS VIR_FROM_STORAGE
+ 
++VIR_LOG_INIT("util.virdevmapper");
++
+ # define PROC_DEVICES "/proc/devices"
+ # define DM_NAME "device-mapper"
+ # define DEV_DM_DIR "/dev/" DM_DIR
+@@ -130,11 +133,15 @@ virDMOpen(void)
+     memset(&dm, 0, sizeof(dm));
+ 
+     if ((controlFD = open(CONTROL_PATH, O_RDWR)) < 0) {
+-        if (errno == ENOENT)
+-            return -2;
+-
+-        virReportSystemError(errno, _("Unable to open %s"), CONTROL_PATH);
+-        return -1;
++        /* We can't talk to devmapper. Produce a warning and let
++         * the caller decide what to do next. */
++        if (errno == ENOENT) {
++            VIR_DEBUG("device mapper not available");
++        } else {
++            VIR_WARN("unable to open %s: %s",
++                     CONTROL_PATH, g_strerror(errno));
++        }
++        return -2;
+     }
+ 
+     if (!virDMIoctl(controlFD, DM_VERSION, &dm, &tmp)) {
+@@ -310,9 +317,9 @@ virDevMapperGetTargets(const char *path,
+ 
+     if ((controlFD = virDMOpen()) < 0) {
+         if (controlFD == -2) {
+-            /* The CONTROL_PATH doesn't exist. Probably the
+-             * module isn't loaded, yet. Don't error out, just
+-             * exit. */
++            /* The CONTROL_PATH doesn't exist or is unusable.
++             * Probably the module isn't loaded, yet. Don't error
++             * out, just exit. */
+             return 0;
+         }
+ 

libvirt.changes

@@ -3,7 +3,8 @@ Wed Aug 19 19:36:52 UTC 2020 - James Fehlig <jfehlig@suse.com>
 
 - virdevmapper: Handle kernel without device-mapper support
   82bb167f-dont-cache-devmapper-major.patch,
-  feb8564a-handle-no-devmapper.patch
+  feb8564a-handle-no-devmapper.patch,
+  53d9af1e-ignore-devmapper-open-errors.patch
   boo#1175465
 
 -------------------------------------------------------------------

libvirt.spec

@@ -339,6 +339,7 @@ Source100:      %{name}-rpmlintrc
 Patch0:         2edd63a0-fix-virFileSetCOW-logic.patch
 Patch1:         82bb167f-dont-cache-devmapper-major.patch
 Patch2:         feb8564a-handle-no-devmapper.patch
+Patch3:         53d9af1e-ignore-devmapper-open-errors.patch
 # Patches pending upstream review
 Patch100:       libxl-dom-reset.patch
 Patch101:       network-don-t-use-dhcp-authoritative-on-static-netwo.patch
@@ -881,6 +882,7 @@ libvirt plugin for NSS for translating domain names into IP addresses.
 %patch0 -p1
 %patch1 -p1
 %patch2 -p1
+%patch3 -p1
 %patch100 -p1
 %patch101 -p1
 %patch150 -p1