FYI, we noticed the following commit (built with gcc-7): commit: 760eca8784712cccd3b1ecbdac31c9e6ee0c5a36 ("xfs: remove the separate cowblocks worker") https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git repair-hard-problems in testcase: xfstests with following parameters: disk: 4HDD fs: xfs test: xfs-reflink test-description: xfstests is a regression test suite for xfs and other files ystems. test-url: git://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): If you fix the issue, kindly add following tag Reported-by: kernel test robot <rong.a.chen(a)intel.com&gt; 2020-01-04 15:17:35 export TEST_DIR=/fs/vda 2020-01-04 15:17:35 export TEST_DEV=/dev/vda 2020-01-04 15:17:35 export FSTYP=xfs 2020-01-04 15:17:35 export SCRATCH_MNT=/fs/scratch 2020-01-04 15:17:35 mkdir /fs/scratch -p 2020-01-04 15:17:35 export SCRATCH_DEV=/dev/vdd 2020-01-04 15:17:35 export SCRATCH_LOGDEV=/dev/vdb 2020-01-04 15:17:35 export SCRATCH_XFS_LIST_METADATA_FIELDS=u3.sfdir3.hdr.parent.i4 2020-01-04 15:17:35 export SCRATCH_XFS_LIST_FUZZ_VERBS=random 2020-01-04 15:17:35 export MKFS_OPTIONS=-mreflink=1 2020-01-04 15:17:35 sed "s:^:xfs/:" //lkp/benchmarks/xfstests/tests/xfs-reflink | grep -F -f merged_ignored_files 2020-01-04 15:17:35 sed "s:^:xfs/:" //lkp/benchmarks/xfstests/tests/xfs-reflink | grep -v -F -f merged_ignored_files 2020-01-04 15:17:35 ./check xfs/127 xfs/128 xfs/129 xfs/130 xfs/139 xfs/140 xfs/169 xfs/179 xfs/180 xfs/182 xfs/184 xfs/192 xfs/193 xfs/198 xfs/200 xfs/204 xfs/207 xfs/208 xfs/209 xfs/210 xfs/211 xfs/212 xfs/213 xfs/214 xfs/215 xfs/218 xfs/219 xfs/221 xfs/223 xfs/224 xfs/225 xfs/226 xfs/228 xfs/230 xfs/231 xfs/232 xfs/237 xfs/239 xfs/240 xfs/241 xfs/243 xfs/245 xfs/247 xfs/248 xfs/249 xfs/251 xfs/254 xfs/255 xfs/256 xfs/257 xfs/258 xfs/265 xfs/280 xfs/307 xfs/308 xfs/309 xfs/312 xfs/313 xfs/315 xfs/316 xfs/319 xfs/320 xfs/321 xfs/323 xfs/324 xfs/325 xfs/326 xfs/327 xfs/328 xfs/330 xfs/344 xfs/345 xfs/346 xfs/347 xfs/372 xfs/373 xfs/410 xfs/411 xfs/420 xfs/421 xfs/435 xfs/440 xfs/441 xfs/442 xfs/464 xfs/483 xfs/507 FSTYP -- xfs (debug) PLATFORM -- Linux/x86_64 vm-snb-cbfbef064ba3 5.5.0-rc4-00064-g760eca8784712 #1 SMP Sat Jan 4 13:40:33 CST 2020 MKFS_OPTIONS -- -f -mreflink=1 /dev/vdd MOUNT_OPTIONS -- /dev/vdd /fs/scratch xfs/127 48s xfs/128 47s xfs/129 17s xfs/130 7s xfs/139 138s xfs/140 430s xfs/169 216s xfs/179 7s xfs/180 8s xfs/182 10s xfs/184 9s xfs/192 8s xfs/193 7s xfs/198 10s xfs/200 9s xfs/204 10s xfs/207 10s xfs/208 10s xfs/209 7s xfs/210 7s xfs/211 917s xfs/212 6s xfs/213 5s xfs/214 6s xfs/215 5s xfs/218 5s xfs/219 6s xfs/221 6s xfs/223 5s xfs/224 5s xfs/225 5s xfs/226 6s xfs/228 5s xfs/230 6s xfs/231 - output mismatch (see /lkp/benchmarks/xfstests/results//xfs/231.out.bad) --- tests/xfs/231.out 2019-12-25 16:49:46.000000000 +0800 +++ /lkp/benchmarks/xfstests/results//xfs/231.out.bad 2020-01-04 15:51:17.105416824 +0800 @@ -1,4 +1,5 @@ QA output created by 231 +cat: /proc/sys/fs/xfs/speculative_cow_prealloc_lifetime: No such file or directory Format and mount Create the original files Compare files @@ -6,11 +7,14 @@ bdbcf02ee0aa977795a79d25fcfdccb1 SCRATCH_MNT/test-231/file2 ... (Run 'diff -u /lkp/benchmarks/xfstests/tests/xfs/231.out /lkp/benchmarks/xfstests/results//xfs/231.out.bad' to see the entire diff) xfs/232 - output mismatch (see /lkp/benchmarks/xfstests/results//xfs/232.out.bad) --- tests/xfs/232.out 2019-12-25 16:49:46.000000000 +0800 +++ /lkp/benchmarks/xfstests/results//xfs/232.out.bad 2020-01-04 15:51:25.238416824 +0800 @@ -1,4 +1,5 @@ QA output created by 232 +cat: /proc/sys/fs/xfs/speculative_cow_prealloc_lifetime: No such file or directory Format and mount Create the original files Compare files @@ -6,11 +7,14 @@ bdbcf02ee0aa977795a79d25fcfdccb1 SCRATCH_MNT/test-232/file2 ... (Run 'diff -u /lkp/benchmarks/xfstests/tests/xfs/232.out /lkp/benchmarks/xfstests/results//xfs/232.out.bad' to see the entire diff) xfs/237 8s xfs/239 7s xfs/240 7s xfs/241 7s xfs/243 6s xfs/245 4s xfs/247 4s xfs/248 5s xfs/249 5s xfs/251 6s xfs/254 6s xfs/255 6s xfs/256 6s xfs/257 7s xfs/258 6s xfs/265 28s xfs/280 5s xfs/307 7s xfs/308 7s xfs/309 30s xfs/312 5s xfs/313 6s xfs/315 9s xfs/316 5s xfs/319 6s xfs/320 7s xfs/321 7s xfs/323 8s xfs/324 9s xfs/325 6s xfs/326 6s xfs/327 4s xfs/328 49s xfs/330 4s xfs/344 6s xfs/345 4s xfs/346 14s xfs/347 7s xfs/372 293s xfs/373 26s xfs/410 31s xfs/411 30s xfs/420 3s xfs/421 4s xfs/435 3s xfs/440 4s xfs/441 3s xfs/442 258s xfs/464 32s xfs/483 27s xfs/507 20s Ran: xfs/127 xfs/128 xfs/129 xfs/130 xfs/139 xfs/140 xfs/169 xfs/179 xfs/180 xfs/182 xfs/184 xfs/192 xfs/193 xfs/198 xfs/200 xfs/204 xfs/207 xfs/208 xfs/209 xfs/210 xfs/211 xfs/212 xfs/213 xfs/214 xfs/215 xfs/218 xfs/219 xfs/221 xfs/223 xfs/224 xfs/225 xfs/226 xfs/228 xfs/230 xfs/231 xfs/232 xfs/237 xfs/239 xfs/240 xfs/241 xfs/243 xfs/245 xfs/247 xfs/248 xfs/249 xfs/251 xfs/254 xfs/255 xfs/256 xfs/257 xfs/258 xfs/265 xfs/280 xfs/307 xfs/308 xfs/309 xfs/312 xfs/313 xfs/315 xfs/316 xfs/319 xfs/320 xfs/321 xfs/323 xfs/324 xfs/325 xfs/326 xfs/327 xfs/328 xfs/330 xfs/344 xfs/345 xfs/346 xfs/347 xfs/372 xfs/373 xfs/410 xfs/411 xfs/420 xfs/421 xfs/435 xfs/440 xfs/441 xfs/442 xfs/464 xfs/483 xfs/507 Failures: xfs/231 xfs/232 Failed 2 of 87 tests To reproduce: # build kernel cd linux cp config-5.5.0-rc4-00064-g760eca8784712 .config make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage modules make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 INSTALL_MOD_PATH=<mod-install-dir> modules_install cd <mod-install-dir> find lib/ | cpio -o -H newc --quiet | gzip > modules.cgz git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k <bzImage> -m modules.cgz job-script # job-script is attached in this email Thanks, Rong Chen