Skip to main content

Browse the archive

Revision 289454ad26a2d752e04b07234a175feda9ec0f4e authored by Naohiro Aota on 05 January 2015, 16:01:03 UTC, committed by Chris Mason on 03 February 2015, 03:24:51 UTC 
btrfs: clear bio reference after submit_one_bio()
 
After submit_one_bio(), `bio' can go away. However submit_extent_page()
leave `bio' referable if submit_one_bio() failed (e.g. -ENOMEM on OOM).
It will cause invalid paging request when submit_extent_page() is called
next time.

I reproduced ENOMEM case with the following script (need
CONFIG_FAIL_PAGE_ALLOC, and CONFIG_FAULT_INJECTION_DEBUG_FS).

  #!/bin/bash

  dmesgout=dmesg.txt
  start=100000
  end=300000
  step=1000

  # btrfs options
  device=/dev/vdb1
  directory=/mnt/btrfs

  # fault-injection options
  percent=100
  times=3

  mkdir -p $directory || exit 1
  mount -o compress $device $directory || exit 1

  rm -f $directory/file || exit 1
  dd if=/dev/zero of=$directory/file bs=1M count=512 || exit 1

  for interval in `seq $start $step $end`; do
          dmesg -C
          echo 1 > /proc/sys/vm/drop_caches
          sync
          export FAILCMD_TYPE=fail_page_alloc
          ./failcmd.sh -p $percent -t $times -i $interval \
                  --ignore-gfp-highmem=N --ignore-gfp-wait=N --min-order=0 \
                  -- \
                  cat $directory/file > /dev/null
          dmesg > ${dmesgout}
          if grep -q BUG: ${dmesgout}; then
                  cat ${dmesgout}
                  exit 1
          fi
  done

  umount $directory
  exit 0

Signed-off-by: Naohiro Aota <naota@elisp.net>
Tested-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
1 parent de554a4
Raw File
mkcompile_h 
#!/bin/sh

TARGET=$1
ARCH=$2
SMP=$3
PREEMPT=$4
CC=$5

vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }

# If compile.h exists already and we don't own autoconf.h
# (i.e. we're not the same user who did make *config), don't
# modify compile.h
# So "sudo make install" won't change the "compiled by <user>"
# do "compiled by root"

if [ -r $TARGET -a ! -O include/generated/autoconf.h ]; then
  vecho "  SKIPPED $TARGET"
  exit 0
fi

# Do not expand names
set -f

# Fix the language to get consistent output
LC_ALL=C
export LC_ALL

if [ -z "$KBUILD_BUILD_VERSION" ]; then
	if [ -r .version ]; then
		VERSION=`cat .version`
	else
		VERSION=0
		echo 0 > .version
	fi
else
	VERSION=$KBUILD_BUILD_VERSION
fi

if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then
	TIMESTAMP=`date`
else
	TIMESTAMP=$KBUILD_BUILD_TIMESTAMP
fi
if test -z "$KBUILD_BUILD_USER"; then
	LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/')
else
	LINUX_COMPILE_BY=$KBUILD_BUILD_USER
fi
if test -z "$KBUILD_BUILD_HOST"; then
	LINUX_COMPILE_HOST=`hostname`
else
	LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST
fi

UTS_VERSION="#$VERSION"
CONFIG_FLAGS=""
if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"

# Truncate to maximum length

UTS_LEN=64
UTS_TRUNCATE="cut -b -$UTS_LEN"

# Generate a temporary compile.h

( echo /\* This file is auto generated, version $VERSION \*/
  if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi

  echo \#define UTS_MACHINE \"$ARCH\"

  echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\"

  echo \#define LINUX_COMPILE_BY \"`echo $LINUX_COMPILE_BY | $UTS_TRUNCATE`\"
  echo \#define LINUX_COMPILE_HOST \"`echo $LINUX_COMPILE_HOST | $UTS_TRUNCATE`\"

  echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | grep ' version '`\"
) > .tmpcompile

# Only replace the real compile.h if the new one is different,
# in order to preserve the timestamp and avoid unnecessary
# recompilations.
# We don't consider the file changed if only the date/time changed.
# A kernel config change will increase the generation number, thus
# causing compile.h to be updated (including date/time) due to the
# changed comment in the
# first line.

if [ -r $TARGET ] && \
      grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \
      grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \
      cmp -s .tmpver.1 .tmpver.2; then
   rm -f .tmpcompile
else
   vecho "  UPD     $TARGET"
   mv -f .tmpcompile $TARGET
fi
rm -f .tmpver.1 .tmpver.2
back to top