Add test_generic_15.sh to verify that async partition scan prevents IO hang when reading partition tables. The test creates ublk devices with fault_inject target and very large delay (60s) to simulate blocked partition table reads, then kills the daemon to verify proper state transitions without hanging: 1. Without recovery support: - Create device with fault_inject and 60s delay - Kill daemon while partition scan may be blocked - Verify device transitions to DEAD state 2. With recovery support (-r 1): - Create device with fault_inject, 60s delay, and recovery - Kill daemon while partition scan may be blocked - Verify device transitions to QUIESCED state Before the async partition scan fix, killing the daemon during partition scan would cause deadlock as partition scan held ub->mutex while waiting for IO. With the async fix, partition scan happens in a work function and flush_work() ensures proper synchronization. Add _add_ublk_dev_no_settle() helper function to skip udevadm settle, which would otherwise hang waiting for partition scan events to complete when partition table read is delayed. Signed-off-by: Ming Lei --- tools/testing/selftests/ublk/Makefile | 1 + tools/testing/selftests/ublk/test_common.sh | 16 +++-- .../testing/selftests/ublk/test_generic_15.sh | 68 +++++++++++++++++++ 3 files changed, 81 insertions(+), 4 deletions(-) create mode 100755 tools/testing/selftests/ublk/test_generic_15.sh diff --git a/tools/testing/selftests/ublk/Makefile b/tools/testing/selftests/ublk/Makefile index 837977b62417..eb0e6cfb00ad 100644 --- a/tools/testing/selftests/ublk/Makefile +++ b/tools/testing/selftests/ublk/Makefile @@ -22,6 +22,7 @@ TEST_PROGS += test_generic_11.sh TEST_PROGS += test_generic_12.sh TEST_PROGS += test_generic_13.sh TEST_PROGS += test_generic_14.sh +TEST_PROGS += test_generic_15.sh TEST_PROGS += test_null_01.sh TEST_PROGS += test_null_02.sh diff --git a/tools/testing/selftests/ublk/test_common.sh b/tools/testing/selftests/ublk/test_common.sh index 6f1c042de40e..ea9a5f3eb70a 100755 --- a/tools/testing/selftests/ublk/test_common.sh +++ b/tools/testing/selftests/ublk/test_common.sh @@ -178,8 +178,9 @@ _have_feature() _create_ublk_dev() { local dev_id; local cmd=$1 + local settle=$2 - shift 1 + shift 2 if [ ! -c /dev/ublk-control ]; then return ${UBLK_SKIP_CODE} @@ -194,7 +195,10 @@ _create_ublk_dev() { echo "fail to add ublk dev $*" return 255 fi - udevadm settle + + if [ "$settle" = "yes" ]; then + udevadm settle + fi if [[ "$dev_id" =~ ^[0-9]+$ ]]; then echo "${dev_id}" @@ -204,14 +208,18 @@ _create_ublk_dev() { } _add_ublk_dev() { - _create_ublk_dev "add" "$@" + _create_ublk_dev "add" "yes" "$@" +} + +_add_ublk_dev_no_settle() { + _create_ublk_dev "add" "no" "$@" } _recover_ublk_dev() { local dev_id local state - dev_id=$(_create_ublk_dev "recover" "$@") + dev_id=$(_create_ublk_dev "recover" "yes" "$@") for ((j=0;j<20;j++)); do state=$(_get_ublk_dev_state "${dev_id}") [ "$state" == "LIVE" ] && break diff --git a/tools/testing/selftests/ublk/test_generic_15.sh b/tools/testing/selftests/ublk/test_generic_15.sh new file mode 100755 index 000000000000..76379362e0a2 --- /dev/null +++ b/tools/testing/selftests/ublk/test_generic_15.sh @@ -0,0 +1,68 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +. "$(cd "$(dirname "$0")" && pwd)"/test_common.sh + +TID="generic_15" +ERR_CODE=0 + +_test_partition_scan_no_hang() +{ + local recovery_flag=$1 + local expected_state=$2 + local dev_id + local state + local daemon_pid + local start_time + local elapsed + + # Create ublk device with fault_inject target and very large delay + # to simulate hang during partition table read + # --delay_us 60000000 = 60 seconds delay + # Use _add_ublk_dev_no_settle to avoid udevadm settle hang waiting + # for partition scan events to complete + if [ "$recovery_flag" = "yes" ]; then + echo "Testing partition scan with recovery support..." + dev_id=$(_add_ublk_dev_no_settle -t fault_inject -q 1 -d 1 --delay_us 60000000 -r 1) + else + echo "Testing partition scan without recovery..." + dev_id=$(_add_ublk_dev_no_settle -t fault_inject -q 1 -d 1 --delay_us 60000000) + fi + + _check_add_dev "$TID" $? + + # The add command should return quickly because partition scan is async. + # Now sleep briefly to let the async partition scan work start and hit + # the delay in the fault_inject handler. + sleep 1 + + # Kill the ublk daemon while partition scan is potentially blocked + # And check state transitions properly + start_time=${SECONDS} + daemon_pid=$(_get_ublk_daemon_pid "${dev_id}") + state=$(__ublk_kill_daemon "${dev_id}" "${expected_state}") + elapsed=$((SECONDS - start_time)) + + # Verify the device transitioned to expected state + if [ "$state" != "${expected_state}" ]; then + echo "FAIL: Device state is $state, expected ${expected_state}" + ERR_CODE=255 + ${UBLK_PROG} del -n "${dev_id}" > /dev/null 2>&1 + return + fi + echo "PASS: Device transitioned to ${expected_state} in ${elapsed}s without hanging" + + # Clean up the device + ${UBLK_PROG} del -n "${dev_id}" > /dev/null 2>&1 +} + +_prep_test "partition_scan" "verify async partition scan prevents IO hang" + +# Test 1: Without recovery support - should transition to DEAD +_test_partition_scan_no_hang "no" "DEAD" + +# Test 2: With recovery support - should transition to QUIESCED +_test_partition_scan_no_hang "yes" "QUIESCED" + +_cleanup_test "partition_scan" +_show_result $TID $ERR_CODE -- 2.47.0