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+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright 2020 Google LLC
+#
+# Trigger the blk_mq_realloc_hw_ctxs() error path.
+
+. tests/block/rc
+. common/null_blk
+
+DESCRIPTION="trigger the blk_mq_realloc_hw_ctxs() error path"
+QUICK=1
+
+requires() {
+ _have_null_blk || return $?
+ _have_module_param null_blk init_hctx || return $?
+}
+
+# Configure one null_blk instance.
+configure_null_blk() {
+ local nullb0="/sys/kernel/config/nullb/nullb0"
+
+ mkdir "$nullb0" &&
+ echo 0 > "$nullb0/completion_nsec" &&
+ echo 512 > "$nullb0/blocksize" &&
+ echo 16 > "$nullb0/size" &&
+ nproc > "$nullb0/submit_queues" &&
+ echo 1 > "$nullb0/memory_backed" &&
+ echo 1 > "$nullb0/power" &&
+ ls -l /dev/nullb* &>>"$FULL"
+}
+
+test() {
+ local i sq=/sys/kernel/config/nullb/nullb0/submit_queues
+
+ : "${TIMEOUT:=30}"
+ if ! _init_null_blk nr_devices=0 queue_mode=2 "init_hctx=$(nproc),100,0,0"; then
+ echo "Loading null_blk failed"
+ return 1
+ fi
+ if ! configure_null_blk; then
+ echo "Configuring null_blk failed"
+ return 1
+ fi
+ if { echo "$(<"$sq")" >$sq; } 2>/dev/null; then
+ for ((i=0;i<100;i++)); do
+ echo 1 >$sq
+ nproc >$sq
+ done
+ else
+ echo "Skipping test because $sq cannot be modified" >>"$FULL"
+ fi
+ rmdir /sys/kernel/config/nullb/nullb0
+ _exit_null_blk
+ echo Passed
+}
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+Passed
Add a test that triggers the code touched by commit d0930bb8f46b ("blk-mq: Fix a recently introduced regression in blk_mq_realloc_hw_ctxs()"). This test only runs if a recently added fault injection feature is available, namely commit 596444e75705 ("null_blk: Add support for init_hctx() fault injection"). Cc: Ming Lei <ming.lei@redhat.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- tests/block/030 | 55 +++++++++++++++++++++++++++++++++++++++++++++ tests/block/030.out | 1 + 2 files changed, 56 insertions(+) create mode 100755 tests/block/030 create mode 100644 tests/block/030.out