[PATCH, V2] xfstests: fail test if it causes a kernel taint

[Eric Sandeen <sandeen@xxxxxxxxxxx>]

This modification will fail a test if it introduces one of
a handful of "serious" kernel taints.  I mask on a few taint
values because using an out of tree module or a non-GPL module
should never fail a test, for example.

Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---

Tested by modifying tests/generic/001 to modprobe a "staging"
driver, and adding the staging taint bit (1024) to the mask.

V2: fail test by modifying the test output so the golden
output check will fail, per dchinner's suggestion.

diff --git a/check b/check
index a79747e..7ba6696 100755
--- a/check
+++ b/check
@@ -446,6 +446,11 @@ do
        fi
        rm -f core $seqres.notrun
 
+       if [ "$HOSTOS" == "Linux" ]; then
+               tainted=`sysctl -n kernel.tainted`
+               let "tainted &= $TAINT_FAIL"
+       fi
+
        start=`_wallclock`
        $timestamp && echo -n " ["`date "+%T"`"]"
        [ ! -x $seq ] && chmod u+x $seq # ensure we can run it
@@ -458,6 +463,19 @@ do
        _fix_malloc <$tmp.rawout >$tmp.out
        rm -f $tmp.rawout
 
+       # See if this run tainted the kernel due to oops, etc
+       # If so, break the test via the golden output file
+       if [ "$HOSTOS" == "Linux" ]
+       then
+               tainted2=`sysctl -n kernel.tainted`
+               let "tainted2 &= $TAINT_FAIL"
+               if [ "$tainted" != "$tainted2" ]
+               then
+                       echo " Kernel taint changed from $tainted to 
$tainted2." >> $tmp.out
+                       echo " See dmesg for details." >> $tmp.out
+               fi
+       fi
+
        if [ -f core ]
        then
            echo -n " [dumped core]"
diff --git a/common/config b/common/config
index 67c1498..6483ded 100644
--- a/common/config
+++ b/common/config
@@ -82,6 +82,15 @@ export PWD=`pwd`
 export MALLOCLIB=${MALLOCLIB:=/usr/lib/libefence.a}
 export 
LOCAL_CONFIGURE_OPTIONS=${LOCAL_CONFIGURE_OPTIONS:=--enable-readline=yes}
 
+# kernel taint values on Linux (from kernel.taint sysctl)
+TAINT_MACHINE_CHECK=16
+TAINT_BAD_PAGE=32
+TAINT_DIED=128
+TAINT_WARNING=512
+# If a test introduces one of these taints we consider it to have failed
+let "TAINT_FAIL=( $TAINT_MACHINE_CHECK | $TAINT_BAD_PAGE | $TAINT_DIED | 
$TAINT_WARNING )"
+export TAINT_FAIL
+
 # $1 = prog to look for, $2* = default pathnames if not found in $PATH
 set_prog_path()
 {