loop/001: verify all partitions are removed

loop/001 does not test whether all partitions are removed successfully
during loop device partition scanning. As a result, the regression
introduced by 0da03cab87e6 ("loop: Fix deadlock when calling
blkdev_reread_part()") can not be detected.

The regression will generate below message in dmesg:

[  464.414043] __loop_clr_fd: partition scan of loop0 failed (rc=-22)

and leave orphan partitions like below:

- /dev/loop0p1
- /sys/block/loop0/loop0p1

This patch verifies all partitions are removed by checking if there is
/sys/block/loopX/loopXpY left. The expected number of partitions left is 0.

Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
[Omar: check devices and sysfs for both before and after]
Signed-off-by: Omar Sandoval <osandov@fb.com>

diff --git a/tests/loop/001 b/tests/loop/001
index 47f760a08859760016914123046c05561db2197c..db225f9277c2a36ac8fa35209738599e8b36c0cf 100755 (executable)
--- a/tests/loop/001
+++ b/tests/loop/001
@@ -3,7 +3,8 @@
 # Copyright (C) 2017 Omar Sandoval
 #
 # Test loop device partition scanning. Regression test for commit e02898b42380
-# ("loop: fix LO_FLAGS_PARTSCAN hang").
+# ("loop: fix LO_FLAGS_PARTSCAN hang") and commit 758a58d0bc67 ("loop: set
+# GENHD_FL_NO_PART_SCAN after blkdev_reread_part()").
 
 . tests/loop/rc
 
@@ -14,6 +15,15 @@ requires() {
        _have_program parted
 }
 
+find_loop_partition_devices() {
+       lsblk -lno NAME | sed -n "s/^${1}p//p" | sort
+}
+
+find_loop_partition_sysfs() {
+       find "$sysfs/" -mindepth 1 -maxdepth 1 -name "$1"'p*' -printf '%f\n' |
+               sed -n "s/^${1}p//p" | sort
+}
+
 test() {
        echo "Running ${TEST_NAME}"
 
@@ -23,10 +33,25 @@ test() {
                mkpart primary 0% 50% \
                mkpart primary 50% 100%
 
+       local loop_device name sysfs
        loop_device="$(losetup -P -f --show "$TMPDIR/img")"
-       lsblk -ln "$loop_device" | wc -l
+       udevadm settle
+       name="$(basename "$loop_device")"
+       sysfs="/sys/block/$name"
+
+       echo "Partition devices"
+       find_loop_partition_devices "$name"
+       echo "Partition sysfs nodes"
+       find_loop_partition_sysfs "$name"
 
        losetup -d "$loop_device"
+       udevadm settle
+
+       echo "Partition devices after detach"
+       find_loop_partition_devices "$name"
+       echo "Partition sysfs nodes after detach"
+       find_loop_partition_sysfs "$name"
+
        rm "$TMPDIR/img"
        echo "Test complete"
 }

diff --git a/tests/loop/001.out b/tests/loop/001.out
index 75979f08c80ffac39a154f5c65a0bf09a3b778f3..2c65264bb6580ad0a0d72901b8a3b2e3e65ba4b7 100644 (file)
--- a/tests/loop/001.out
+++ b/tests/loop/001.out
@@ -1,3 +1,10 @@
 Running loop/001
-3
+Partition devices
+1
+2
+Partition sysfs nodes
+1
+2
+Partition devices after detach
+Partition sysfs nodes after detach
 Test complete