On 5/25/25 10:24 PM, Christoph Hellwig wrote:
Umm, Bart I really expected better from you. You're ducking around
providing a reproducer for over a week and waste multiple peoples
time to tell us the only reproducer is your out of tree thingy
reject upstream before? That's not really how Linux developement
works.
A reproducer for the blktests framework is available below. It took me
more time than I had expected to come up with a reproducer because I was
initially looking in the wrong direction (device mapper). As one can
see, the reproducer below does not involve any device mapper driver.
Do you plan to work on a fix or do you perhaps expect me to do this?
Thanks,
Bart.
$ cat tests/zbd/014
#!/bin/bash
# SPDX-License-Identifier: GPL-3.0+
# Copyright (C) 2025 Google LLC
#
# Trigger multiple splitting of a bio. About the values of the size
parameters
# in this test:
# - The zone size is 4 MiB and is larger than max_sectors_kb.
# - The maximum bio size supported by the code in
block/blk-crypto-fallback.c
# is BIO_MAX_VECS * PAGE_SIZE or 1 MiB if the page size is 4 KiB.
# - max_sectors_kb has been set to 512 KiB to cause further bio splitting.
. tests/zbd/rc
. common/null_blk
DESCRIPTION="test multiple bio splitting"
QUICK=1
requires() {
_have_driver f2fs
_have_driver null_blk
_have_program fscrypt
_have_program getconf
_have_program mkfs.f2fs
for o in BLK_INLINE_ENCRYPTION_FALLBACK FS_ENCRYPTION_INLINE_CRYPT; do
if ! _check_kernel_option "$o"; then
SKIP_REASONS+=("Kernel option $o has not been enabled")
fi
done
}
trace_block_io() {
(
set -e
cd /sys/kernel/tracing
lsof -t trace_pipe | xargs -r kill
echo 1024 > buffer_size_kb
echo nop > current_tracer
echo 0 > tracing_on
echo > trace
echo 0 > events/enable
echo 1 > events/block/enable
echo 0 > events/block/block_dirty_buffer/enable
echo 0 > events/block/block_plug/enable
echo 0 > events/block/block_touch_buffer/enable
echo 0 > events/block/block_unplug/enable
grep -lw 1 events/block/*/enable | while read -r event_path; do
filter_path="${event_path%enable}filter"
echo "$1" > "$filter_path"
done
echo 1 > tracing_on
echo "Tracing has been enabled" >>"$FULL"
cat trace_pipe > "${FULL%.full}-block-trace.txt"
)
}
stop_tracing() {
kill "$1"
(
set -e
cd /sys/kernel/tracing
echo 0 > tracing_on
echo 0 > events/enable
)
}
report_stats() {
local pfx=$1 before after
read -r -a before <<<"$2"
read -r -a after <<<"$3"
local reads=$((after[0]-before[0]))
local rmerge=$((after[1]-before[1]))
local writes=$((after[4]-before[4]))
local wmerge=$((after[5]-before[5]))
echo "$pfx reads: $reads rmerge: $rmerge writes: $writes wmerge: $wmerge"
}
devno() {
IFS=: read -r maj min <"/sys/class/block/$(basename "$1")/dev"
# From <linux/kdev_t.h> MINORBITS = 20
echo $(((maj << 20) + min))
}
test() {
echo "Running ${TEST_NAME}"
local page_size
page_size=$(getconf PAGE_SIZE) || return $?
local mount_dir="$TMPDIR/mnt"
umount /dev/nullb1 >>"$FULL" 2>&1
_remove_null_blk_devices
# A small conventional block device for the F2FS metadata.
local null_blk_params=(
blocksize=4096
discard=1
max_sectors=$(((1 << 32) - 1))
memory_backed=1
size=64 # MiB
submit_queues=1
power=1
)
_configure_null_blk nullb1 "${null_blk_params[@]}"
local cdev=/dev/nullb1
# A larger zoned block device for the data.
local null_blk_params=(
blocksize=4096
completion_nsec=10000000 # 10 ms
irqmode=2
max_sectors=$(((1 << 32) - 1))
memory_backed=1
hw_queue_depth=1
size=1024 # MiB
submit_queues=1
zone_size="$((page_size >> 10))" # 1024 times the page size.
zoned=1
power=1
)
_configure_null_blk nullb2 "${null_blk_params[@]}" || return $?
local zdev_basename=nullb2
local zdev=/dev/${zdev_basename}
local zdev_devno
zdev_devno=$(devno "$zdev")
{
local
max_sectors_zdev=/sys/class/block/"${zdev_basename}"/queue/max_sectors_kb
echo $((128 * page_size)) > "${max_sectors_zdev}"
echo "${zdev_basename}: max_sectors_kb=$(<"${max_sectors_zdev}")"
ls -ld "${cdev}" "${zdev}"
echo "${zdev_basename} settings:"
(cd "/sys/class/block/$zdev_basename/queue" && grep -vw 0 ./*)
} >>"${FULL}" 2>&1
trace_block_io "dev == ${zdev_devno}" &
local trace_pid=$!
while ! grep -q 'Tracing has been enabled' "$FULL"; do
sleep .1
done
{
mkfs.f2fs -q -O encrypt -m "${cdev}" -c "${zdev}" &&
mkdir -p "${mount_dir}" &&
mount -o inlinecrypt -t f2fs "${cdev}" "${mount_dir}" &&
local encrypted_dir="${mount_dir}/encrypted" &&
mkdir -p "${encrypted_dir}"
fscrypt setup "${mount_dir}" </dev/null
local keyfile=$TMPDIR/keyfile &&
dd if=/dev/zero of="$keyfile" bs=32 count=1 status=none &&
fscrypt encrypt "${encrypted_dir}" --source=raw_key \
--name=protector --key="$keyfile" &&
fscrypt status "${encrypted_dir}" &&
local before after &&
read -r -a before <"/sys/class/block/${zdev_basename}/stat" &&
echo "Starting IO" &&
local cmd="dd if=/dev/zero of=${encrypted_dir}/file bs=64M count=15
conv=fdatasync" &&
echo "$cmd" &&
eval "$cmd" &&
ls -ld "${mount_dir}/encrypted/file" &&
read -r -a after <"/sys/class/block/${zdev_basename}/stat" &&
report_stats "zdev:" "${before[*]}" "${after[*]}"
} >>"$FULL" 2>&1 || fail=true
umount "${mount_dir}" >>"${FULL}" 2>&1
[ -n "${trace_pid}" ] && kill "${trace_pid}"
_exit_null_blk
if [ -z "$fail" ]; then
echo "Test complete"
else
echo "Test failed"
return 1
fi
}
