add tests for file system on devices using protection information v2

add tests for file system on devices using protection information v2

[Christoph Hellwig]

Hi all,

this series adds support to exercise I/O on file systems using protection
information in the device, including that corruption is properly
reported.

The second test requires a patch to inject corruption into scsi_debug
that was posted to the linux-scsi list.

Changes since v1:
 - fix various requirements
 - use _exit
 - cleanup up the scsi_debug options building
 - add a new PI group
 - mark one of the new tests dangerous as it can crash Linux 7.2 and earlier

[PATCH 1/5] common/scsi_debug: don't slow down I/O

[Christoph Hellwig]

scsi_debug by defaults delays I/O and doesn't support multi-page I/O.
Flipping these defaults speed up each test using scsi_debug by more than
an order of magnitute on my test systems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 common/scsi_debug | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/common/scsi_debug b/common/scsi_debug
index c3fe7be623fa..af51905dc4ba 100644
--- a/common/scsi_debug
+++ b/common/scsi_debug
@@ -59,9 +59,19 @@ _get_scsi_debug_dev()
 		let physical=physical/2
 		let phys_exp=phys_exp+1
 	done
-	opts="sector_size=$logical physblk_exp=$phys_exp lowest_aligned=$unaligned dev_size_mb=$size $@"
-	echo "scsi_debug options $opts" >> $seqres.full
-	modprobe scsi_debug $opts
+
+	local opts=(
+		"sector_size=$logical"
+		"physblk_exp=$phys_exp"
+		"lowest_aligned=$unaligned"
+		"dev_size_mb=$size"
+		"delay=0"
+		"clustering=1"
+	)
+	opts+=("$@")
+
+	echo "scsi_debug options ${opts[*]}" >> $seqres.full
+	modprobe scsi_debug "${opts[@]}"
 	[ $? -eq 0 ] || _fail "scsi_debug modprobe failed"
 	$UDEV_SETTLE_PROG
 	device=`grep -wl scsi_debug /sys/block/sd*/device/model | awk -F / '{print $4}'`
-- 
2.53.0

[PATCH 2/5] common: add a _sysfs_block_integrity_path helper

[Christoph Hellwig]

Add a helper function to find the sysfs integrity directory for a given
block device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 common/rc | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/common/rc b/common/rc
index 02bdb31a76a6..61a899da3bd7 100644
--- a/common/rc
+++ b/common/rc
@@ -5257,6 +5257,31 @@ _sysfs_queue_path()
 	fi
 }
 
+# Get the sysfs block device integrity/ path for a block device, handling
+# partitions correctly.
+_sysfs_block_integrity_path()
+{
+	local dev parent
+	dev=$(_short_dev "$1")
+
+	# For partitions, integrity details are in the parent device's sysfs dir
+	if [ -e "/sys/class/block/$dev/partition" ]; then
+		parent=$(basename "$(readlink -f /sys/class/block/$dev/..)")
+	else
+		parent="$dev"
+	fi
+
+	local integrity_path="/sys/block/$parent/integrity"
+
+	# Verify the path exists before returning
+	if [ -e "$integrity_path" ]; then
+		echo "$integrity_path"
+		return 0
+	fi
+
+	return 1
+}
+
 # Get the minimum block size of a file.  Usually this is the
 # minimum fs block size, but some filesystems (ocfs2) do block
 # mappings in larger units.
-- 
2.53.0

[PATCH 3/5] add a "pi" group

[Christoph Hellwig]

Add a group for tests exercising T10 protection information.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 doc/group-names.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/doc/group-names.txt b/doc/group-names.txt
index 424e2c4a1ca6..ef6b8f51cf87 100644
--- a/doc/group-names.txt
+++ b/doc/group-names.txt
@@ -137,6 +137,7 @@ tape			dump and restore with a tape
 tempfsid		temporary fsid
 thin			thin provisioning
 trim			FITRIM ioctl
+pi			Protection Information
 udf			UDF functionality tests
 union			tests from the unionmount test suite
 unlink			O_TMPFILE unlinked files
-- 
2.53.0

[PATCH 4/5] generic: test I/O on devices with T10 protection information

[Christoph Hellwig]

Add a test that runs fsx in buffered and direct I/O mode on T10 PI
type 1, 2, 3 with and without strip/insert using scsi_debug.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 tests/generic/2301     | 91 ++++++++++++++++++++++++++++++++++++++++++
 tests/generic/2301.out | 73 +++++++++++++++++++++++++++++++++
 2 files changed, 164 insertions(+)
 create mode 100755 tests/generic/2301
 create mode 100644 tests/generic/2301.out

diff --git a/tests/generic/2301 b/tests/generic/2301
new file mode 100755
index 000000000000..ba6952855f55
--- /dev/null
+++ b/tests/generic/2301
@@ -0,0 +1,91 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2026 Christoph Hellwig
+#
+# FS QA Test No. 2301
+#
+# Basix FSX sanity check when using T10 protection information
+#
+. ./common/preamble
+_begin_fstest auto rw pi dangerous
+
+_cleanup()
+{
+	cd /
+	rm -r -f $tmp.*
+	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
+	_put_scsi_debug_dev
+}
+
+. ./common/scsi_debug
+
+_require_debugfs
+_require_scsi_debug
+# If TEST_DEV is block device, make sure current fs is a localfs which can be
+# written on scsi_debug device
+_require_test
+_require_block_device $TEST_DEV
+_require_odirect
+
+size=$(_small_fs_size_mb 256)
+
+# like run_fsx(), but using a custom path
+fsx_run()
+{
+	_run_fsx_on_file $SCSI_DEBUG_MNT/junk $@ || _exit 1
+}
+
+test_dif()
+{
+	local pi_type=$1
+	local pi_enable="$2"
+
+	scsi_debug_pi_opts="write_same_length=0 dif=${pi_type} dix=1"
+	SCSI_DEBUG_DEV=`_get_scsi_debug_dev 512 512 0 $size $scsi_debug_pi_opts`
+
+	SCSI_DEBUG_MNT="$TEST_DIR/scsi_debug_$seq"
+	rm -rf $SCSI_DEBUG_MNT
+	mkdir $SCSI_DEBUG_MNT
+
+	_mkfs_dev $SCSI_DEBUG_DEV || \
+		_fail "Can't make $FSTYP on DIF-enabled scsi_debug device"
+	run_check _mount $SCSI_DEBUG_DEV $SCSI_DEBUG_MNT
+	bsize=$($here/src/min_dio_alignment $SCSI_DEBUG_MNT $SCSI_DEBUG_DEV)
+
+	local integrity_path="$(_sysfs_block_integrity_path $SCSI_DEBUG_DEV)"
+	echo $pi_enable > $integrity_path/read_verify
+	echo $pi_enable > $integrity_path/write_generate
+
+	# fsx load similar to generic/091
+	echo "Testing direct I/O for DIF type $pi_type (enabled: $pi_enable)"
+	local dio_opts="-r PSIZE -t BSIZE -w BSIZE"
+	fsx_run -N 10000            -l 500000 -r BSIZE -w BSIZE -Z -R -W
+	fsx_run -N 10000  -o 8192   -l 500000 -r BSIZE -w BSIZE -Z -R -W
+	fsx_run -N 10000  -o 32768  -l 500000 -r BSIZE -w BSIZE -Z -R -W
+	fsx_run -N 10000  -o 8192   -l 500000 -r BSIZE -w BSIZE -Z -R -W
+	fsx_run -N 10000  -o 32768  -l 500000 -r BSIZE -w BSIZE -Z -R -W
+	fsx_run -N 10000  -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
+
+	# fsx load similar to generic/091 but using buffered I/O
+	echo "Testing buffered I/O for DIF type $pi_type (enabled: $pi_enable)"
+	fsx_run -N 10000            -l 500000
+	fsx_run -N 10000  -o 8192   -l 500000
+	fsx_run -N 10000  -o 32768  -l 500000
+	fsx_run -N 10000  -o 128000 -l 500000
+
+	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
+	_put_scsi_debug_dev
+}
+
+# Test with PI fully enabled
+test_dif 1 1
+test_dif 2 1
+test_dif 3 1
+
+# Test with strip / insert in the HBA
+test_dif 1 0
+test_dif 2 0
+test_dif 3 0
+
+# success, all done
+_exit 0
diff --git a/tests/generic/2301.out b/tests/generic/2301.out
new file mode 100644
index 000000000000..dda88676a219
--- /dev/null
+++ b/tests/generic/2301.out
@@ -0,0 +1,73 @@
+QA output created by 2301
+Testing direct I/O for DIF type 1 (enabled: 1)
+fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
+Testing buffered I/O for DIF type 1 (enabled: 1)
+fsx -N 10000 -l 500000
+fsx -N 10000 -o 8192 -l 500000
+fsx -N 10000 -o 32768 -l 500000
+fsx -N 10000 -o 128000 -l 500000
+Testing direct I/O for DIF type 2 (enabled: 1)
+fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
+Testing buffered I/O for DIF type 2 (enabled: 1)
+fsx -N 10000 -l 500000
+fsx -N 10000 -o 8192 -l 500000
+fsx -N 10000 -o 32768 -l 500000
+fsx -N 10000 -o 128000 -l 500000
+Testing direct I/O for DIF type 3 (enabled: 1)
+fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
+Testing buffered I/O for DIF type 3 (enabled: 1)
+fsx -N 10000 -l 500000
+fsx -N 10000 -o 8192 -l 500000
+fsx -N 10000 -o 32768 -l 500000
+fsx -N 10000 -o 128000 -l 500000
+Testing direct I/O for DIF type 1 (enabled: 0)
+fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
+Testing buffered I/O for DIF type 1 (enabled: 0)
+fsx -N 10000 -l 500000
+fsx -N 10000 -o 8192 -l 500000
+fsx -N 10000 -o 32768 -l 500000
+fsx -N 10000 -o 128000 -l 500000
+Testing direct I/O for DIF type 2 (enabled: 0)
+fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
+Testing buffered I/O for DIF type 2 (enabled: 0)
+fsx -N 10000 -l 500000
+fsx -N 10000 -o 8192 -l 500000
+fsx -N 10000 -o 32768 -l 500000
+fsx -N 10000 -o 128000 -l 500000
+Testing direct I/O for DIF type 3 (enabled: 0)
+fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
+fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
+Testing buffered I/O for DIF type 3 (enabled: 0)
+fsx -N 10000 -l 500000
+fsx -N 10000 -o 8192 -l 500000
+fsx -N 10000 -o 32768 -l 500000
+fsx -N 10000 -o 128000 -l 500000
-- 
2.53.0

[PATCH 5/5] generic: test corruption detection using T10 protection information

[Christoph Hellwig]

Add a test that simulates bit flips in data and misdirected writes and
checks that file systems detect it when run on devices using protection
information.

This requires the new scsi_debug corruption injection.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 tests/generic/2302     | 128 +++++++++++++++++++++++++++++++++++++++++
 tests/generic/2302.out |  21 +++++++
 2 files changed, 149 insertions(+)
 create mode 100755 tests/generic/2302
 create mode 100644 tests/generic/2302.out

diff --git a/tests/generic/2302 b/tests/generic/2302
new file mode 100755
index 000000000000..4a9d9165174b
--- /dev/null
+++ b/tests/generic/2302
@@ -0,0 +1,128 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2026 Christoph Hellwig
+#
+# FS QA Test No. 2302
+#
+# Test that T10 DIF detects bitflips and misplaced writes.
+#
+. ./common/preamble
+_begin_fstest auto rw pi
+
+_cleanup()
+{
+	cd /
+	rm -r -f $tmp.*
+	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
+	_put_scsi_debug_dev
+}
+
+. ./common/scsi_debug
+. ./common/filter
+
+_require_debugfs
+_require_scsi_debug
+# If TEST_DEV is block device, make sure current fs is a localfs which can be
+# written on scsi_debug device
+_require_test
+_require_block_device $TEST_DEV
+_require_xfs_io_command fiemap
+_require_odirect
+
+# FIEMAP on Btrfs returns logical addresses within the filesystem's address
+# space, not physical device offsets. Writing to these offsets on $SCRATCH_DEV
+# would corrupt the filesystem in multi-device setups.
+_exclude_fs btrfs
+
+size=$(_small_fs_size_mb 256)
+
+test_dif()
+{
+	local pi_type=$1
+	local last=$2
+	local bit_errors=$3
+	local reftag_adjust=$4
+
+	echo -n "Testing DIF type $pi_type "
+	if [ "$bit_errors" -gt "0" ]; then
+		echo -n "bit errors ($bit_errors) in "
+	fi
+	if [ "$reftag_adjust" -ne "0" ]; then
+		echo -n "reftag adjustment by $reftag_adjust in "
+	fi
+	if [ "$last" -eq 1 ]; then
+		echo "last sector"
+	else
+		echo "first sector"
+	fi
+
+	scsi_debug_pi_opts="write_same_length=0 dif=${pi_type} dix=1"
+	SCSI_DEBUG_DEV=`_get_scsi_debug_dev 512 512 0 $size $scsi_debug_pi_opts`
+
+	SCSI_DEBUG_MNT="$TEST_DIR/scsi_debug_$seq"
+	rm -rf $SCSI_DEBUG_MNT
+	mkdir $SCSI_DEBUG_MNT
+
+	_mkfs_dev $SCSI_DEBUG_DEV || \
+		_fail "Can't make $FSTYP on DIF-enabled scsi_debug device"
+	run_check _mount $SCSI_DEBUG_DEV $SCSI_DEBUG_MNT
+
+	local blksz=$(_get_block_size $SCSI_DEBUG_MNT)
+	local testfile="$SCSI_DEBUG_MNT/test"
+
+	$XFS_IO_PROG -d -f \
+		-c "pwrite -S 0x66 0 $((128 * blksz))" \
+		-c fsync \
+		$testfile >> $seqres.full 2>&1
+
+	local phys_blk=$(_get_file_extent_sector $testfile 0)
+	if [ -z "$phys_blk" ]; then
+		_fail "$test_name: failed to get physical block offset via fiemap"
+	fi
+
+	local dev=$(_short_dev $SCSI_DEBUG_DEV)
+	local debugfs_dir=$(ls /sys/block/$dev/device/scsi_device/)
+	local debugfs_file="/sys/kernel/debug/scsi_debug/$debugfs_dir/corrupt"
+
+	if [ ! -f "$debugfs_file" ]; then
+		_notrun "scsi_debug corruption injection not supported"
+	fi
+
+	if [ "$last" -eq 1 ]; then
+		echo "adding to $phys_blk" >> $seqres.full
+		phys_blk=$((phys_blk + 127))
+	fi
+
+	echo "lba=$phys_blk,num=1,bit_errors=$bit_errors,reftag_adjust=$reftag_adjust" \
+		 > $debugfs_file
+
+	$XFS_IO_PROG -d -f \
+		-c "pread 0 $((128 * blksz))" \
+		$testfile
+
+	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
+	_put_scsi_debug_dev
+}
+
+# test data corruption in first block
+test_dif 1 0 2 0
+test_dif 2 0 2 0
+test_dif 3 0 2 0
+
+# test data corruption in last block
+test_dif 1 1 2 0
+test_dif 2 1 2 0
+test_dif 3 1 2 0
+
+
+# Note: Type 3 doesn't have a refrag, so don't test it
+
+# reftag mismatch in first block
+test_dif 1 0 0 8
+test_dif 2 0 0 8
+
+# reftag mismatch in last block
+test_dif 1 1 0 8
+test_dif 2 1 0 8
+
+_exit 0
diff --git a/tests/generic/2302.out b/tests/generic/2302.out
new file mode 100644
index 000000000000..03b68d904943
--- /dev/null
+++ b/tests/generic/2302.out
@@ -0,0 +1,21 @@
+QA output created by 2302
+Testing DIF type 1 bit errors (2) in first sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 2 bit errors (2) in first sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 3 bit errors (2) in first sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 1 bit errors (2) in last sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 2 bit errors (2) in last sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 3 bit errors (2) in last sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 1 reftag adjustment by 8 in first sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 2 reftag adjustment by 8 in first sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 1 reftag adjustment by 8 in last sector
+pread: Invalid or incomplete multibyte or wide character
+Testing DIF type 2 reftag adjustment by 8 in last sector
+pread: Invalid or incomplete multibyte or wide character
-- 
2.53.0

Re: [PATCH 1/5] common/scsi_debug: don't slow down I/O

[John Garry]

On 21/08/2026 06:11, Christoph Hellwig wrote:
> scsi_debug by defaults delays I/O 

Maybe we can just make delay=0 default for that driver. Or use ndelay > 0.

> and doesn't support multi-page I/O.
> Flipping these defaults speed up each test using scsi_debug by more than
> an order of magnitute on my test systems.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

FWIW:

Reviewed-by: John Garry <john.g.garry@oracle.com>

> ---
>   common/scsi_debug | 16 +++++++++++++---
>   1 file changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/common/scsi_debug b/common/scsi_debug
> index c3fe7be623fa..af51905dc4ba 100644
> --- a/common/scsi_debug
> +++ b/common/scsi_debug
> @@ -59,9 +59,19 @@ _get_scsi_debug_dev()
>   		let physical=physical/2
>   		let phys_exp=phys_exp+1
>   	done
> -	opts="sector_size=$logical physblk_exp=$phys_exp lowest_aligned=$unaligned dev_size_mb=$size $@"
> -	echo "scsi_debug options $opts" >> $seqres.full
> -	modprobe scsi_debug $opts
> +
> +	local opts=(
> +		"sector_size=$logical"
> +		"physblk_exp=$phys_exp"
> +		"lowest_aligned=$unaligned"
> +		"dev_size_mb=$size"
> +		"delay=0"
> +		"clustering=1"
> +	)
> +	opts+=("$@")
> +
> +	echo "scsi_debug options ${opts[*]}" >> $seqres.full
> +	modprobe scsi_debug "${opts[@]}"
>   	[ $? -eq 0 ] || _fail "scsi_debug modprobe failed"
>   	$UDEV_SETTLE_PROG
>   	device=`grep -wl scsi_debug /sys/block/sd*/device/model | awk -F / '{print $4}'`

Re: [PATCH 1/5] common/scsi_debug: don't slow down I/O

[Bart Van Assche]

On 8/21/26 12:41 AM, John Garry wrote:
> On 21/08/2026 06:11, Christoph Hellwig wrote:
>> scsi_debug by defaults delays I/O 
> 
> Maybe we can just make delay=0 default for that driver. Or use ndelay > 0.

I'm in favor of changing the default delay to zero. It's what most users
need and it's easy to forget to specify delay=0 when loading scsi_debug.

Thanks,

Bart.

Re: [PATCH 1/5] common/scsi_debug: don't slow down I/O

[Darrick J. Wong]

On Fri, Aug 21, 2026 at 09:14:29AM -0700, Bart Van Assche wrote:
> On 8/21/26 12:41 AM, John Garry wrote:
> > On 21/08/2026 06:11, Christoph Hellwig wrote:
> > > scsi_debug by defaults delays I/O
> > 
> > Maybe we can just make delay=0 default for that driver. Or use ndelay > 0.
> 
> I'm in favor of changing the default delay to zero. It's what most users
> need and it's easy to forget to specify delay=0 when loading scsi_debug.

I didn't even *know* that you had to do that!

I agree with these changes.
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

> Thanks,
> 
> Bart.
> 

Re: [PATCH 2/5] common: add a _sysfs_block_integrity_path helper

[Darrick J. Wong]

On Fri, Aug 21, 2026 at 07:11:27AM +0200, Christoph Hellwig wrote:
> Add a helper function to find the sysfs integrity directory for a given
> block device.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  common/rc | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/common/rc b/common/rc
> index 02bdb31a76a6..61a899da3bd7 100644
> --- a/common/rc
> +++ b/common/rc
> @@ -5257,6 +5257,31 @@ _sysfs_queue_path()
>  	fi
>  }
>  
> +# Get the sysfs block device integrity/ path for a block device, handling
> +# partitions correctly.
> +_sysfs_block_integrity_path()
> +{
> +	local dev parent
> +	dev=$(_short_dev "$1")
> +
> +	# For partitions, integrity details are in the parent device's sysfs dir
> +	if [ -e "/sys/class/block/$dev/partition" ]; then
> +		parent=$(basename "$(readlink -f /sys/class/block/$dev/..)")
> +	else
> +		parent="$dev"
> +	fi

I wonder if this part should get pulled out into a _sysfs_block_path
helper, since the code is already in _sysfs_queue_path?

--D

> +
> +	local integrity_path="/sys/block/$parent/integrity"
> +
> +	# Verify the path exists before returning
> +	if [ -e "$integrity_path" ]; then
> +		echo "$integrity_path"
> +		return 0
> +	fi
> +
> +	return 1
> +}
> +
>  # Get the minimum block size of a file.  Usually this is the
>  # minimum fs block size, but some filesystems (ocfs2) do block
>  # mappings in larger units.
> -- 
> 2.53.0
> 
> 

Re: [PATCH 3/5] add a "pi" group

[Darrick J. Wong]

On Fri, Aug 21, 2026 at 07:11:28AM +0200, Christoph Hellwig wrote:
> Add a group for tests exercising T10 protection information.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks good,
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

> ---
>  doc/group-names.txt | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/doc/group-names.txt b/doc/group-names.txt
> index 424e2c4a1ca6..ef6b8f51cf87 100644
> --- a/doc/group-names.txt
> +++ b/doc/group-names.txt
> @@ -137,6 +137,7 @@ tape			dump and restore with a tape
>  tempfsid		temporary fsid
>  thin			thin provisioning
>  trim			FITRIM ioctl
> +pi			Protection Information
>  udf			UDF functionality tests
>  union			tests from the unionmount test suite
>  unlink			O_TMPFILE unlinked files
> -- 
> 2.53.0
> 
> 

Re: [PATCH 4/5] generic: test I/O on devices with T10 protection information

[Darrick J. Wong]

On Fri, Aug 21, 2026 at 07:11:29AM +0200, Christoph Hellwig wrote:
> Add a test that runs fsx in buffered and direct I/O mode on T10 PI
> type 1, 2, 3 with and without strip/insert using scsi_debug.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  tests/generic/2301     | 91 ++++++++++++++++++++++++++++++++++++++++++
>  tests/generic/2301.out | 73 +++++++++++++++++++++++++++++++++
>  2 files changed, 164 insertions(+)
>  create mode 100755 tests/generic/2301
>  create mode 100644 tests/generic/2301.out
> 
> diff --git a/tests/generic/2301 b/tests/generic/2301
> new file mode 100755
> index 000000000000..ba6952855f55
> --- /dev/null
> +++ b/tests/generic/2301
> @@ -0,0 +1,91 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2026 Christoph Hellwig
> +#
> +# FS QA Test No. 2301
> +#
> +# Basix FSX sanity check when using T10 protection information
> +#
> +. ./common/preamble
> +_begin_fstest auto rw pi dangerous

Why dangerous?  Can this crash the system?

> +
> +_cleanup()
> +{
> +	cd /
> +	rm -r -f $tmp.*
> +	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
> +	_put_scsi_debug_dev
> +}
> +
> +. ./common/scsi_debug
> +
> +_require_debugfs
> +_require_scsi_debug
> +# If TEST_DEV is block device, make sure current fs is a localfs which can be
> +# written on scsi_debug device
> +_require_test
> +_require_block_device $TEST_DEV
> +_require_odirect
> +
> +size=$(_small_fs_size_mb 256)
> +
> +# like run_fsx(), but using a custom path
> +fsx_run()
> +{
> +	_run_fsx_on_file $SCSI_DEBUG_MNT/junk $@ || _exit 1
> +}
> +
> +test_dif()
> +{
> +	local pi_type=$1
> +	local pi_enable="$2"
> +
> +	scsi_debug_pi_opts="write_same_length=0 dif=${pi_type} dix=1"
> +	SCSI_DEBUG_DEV=`_get_scsi_debug_dev 512 512 0 $size $scsi_debug_pi_opts`
> +
> +	SCSI_DEBUG_MNT="$TEST_DIR/scsi_debug_$seq"
> +	rm -rf $SCSI_DEBUG_MNT
> +	mkdir $SCSI_DEBUG_MNT
> +
> +	_mkfs_dev $SCSI_DEBUG_DEV || \
> +		_fail "Can't make $FSTYP on DIF-enabled scsi_debug device"

I wonder, wouldn't it help to broaden feature testing coverage if we
could inject the scratch device's mkfs/mount options here?  With just a
bare _mkfs_dev you only test the mkfs defaults.  For example, you won't
be testing xfs with metadir and t10 until mkfs.xfs turns that on by
default.

That said, the big problem with that is that there's only one scsi-debug
device and multi-device scratch fs options won't work with that.  I'm
not ride-or-die for this, but I thought it was worth mentioning.

--D

> +	run_check _mount $SCSI_DEBUG_DEV $SCSI_DEBUG_MNT
> +	bsize=$($here/src/min_dio_alignment $SCSI_DEBUG_MNT $SCSI_DEBUG_DEV)
> +
> +	local integrity_path="$(_sysfs_block_integrity_path $SCSI_DEBUG_DEV)"
> +	echo $pi_enable > $integrity_path/read_verify
> +	echo $pi_enable > $integrity_path/write_generate
> +
> +	# fsx load similar to generic/091
> +	echo "Testing direct I/O for DIF type $pi_type (enabled: $pi_enable)"
> +	local dio_opts="-r PSIZE -t BSIZE -w BSIZE"
> +	fsx_run -N 10000            -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +	fsx_run -N 10000  -o 8192   -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +	fsx_run -N 10000  -o 32768  -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +	fsx_run -N 10000  -o 8192   -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +	fsx_run -N 10000  -o 32768  -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +	fsx_run -N 10000  -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
> +
> +	# fsx load similar to generic/091 but using buffered I/O
> +	echo "Testing buffered I/O for DIF type $pi_type (enabled: $pi_enable)"
> +	fsx_run -N 10000            -l 500000
> +	fsx_run -N 10000  -o 8192   -l 500000
> +	fsx_run -N 10000  -o 32768  -l 500000
> +	fsx_run -N 10000  -o 128000 -l 500000
> +
> +	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
> +	_put_scsi_debug_dev
> +}
> +
> +# Test with PI fully enabled
> +test_dif 1 1
> +test_dif 2 1
> +test_dif 3 1
> +
> +# Test with strip / insert in the HBA
> +test_dif 1 0
> +test_dif 2 0
> +test_dif 3 0
> +
> +# success, all done
> +_exit 0
> diff --git a/tests/generic/2301.out b/tests/generic/2301.out
> new file mode 100644
> index 000000000000..dda88676a219
> --- /dev/null
> +++ b/tests/generic/2301.out
> @@ -0,0 +1,73 @@
> +QA output created by 2301
> +Testing direct I/O for DIF type 1 (enabled: 1)
> +fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
> +Testing buffered I/O for DIF type 1 (enabled: 1)
> +fsx -N 10000 -l 500000
> +fsx -N 10000 -o 8192 -l 500000
> +fsx -N 10000 -o 32768 -l 500000
> +fsx -N 10000 -o 128000 -l 500000
> +Testing direct I/O for DIF type 2 (enabled: 1)
> +fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
> +Testing buffered I/O for DIF type 2 (enabled: 1)
> +fsx -N 10000 -l 500000
> +fsx -N 10000 -o 8192 -l 500000
> +fsx -N 10000 -o 32768 -l 500000
> +fsx -N 10000 -o 128000 -l 500000
> +Testing direct I/O for DIF type 3 (enabled: 1)
> +fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
> +Testing buffered I/O for DIF type 3 (enabled: 1)
> +fsx -N 10000 -l 500000
> +fsx -N 10000 -o 8192 -l 500000
> +fsx -N 10000 -o 32768 -l 500000
> +fsx -N 10000 -o 128000 -l 500000
> +Testing direct I/O for DIF type 1 (enabled: 0)
> +fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
> +Testing buffered I/O for DIF type 1 (enabled: 0)
> +fsx -N 10000 -l 500000
> +fsx -N 10000 -o 8192 -l 500000
> +fsx -N 10000 -o 32768 -l 500000
> +fsx -N 10000 -o 128000 -l 500000
> +Testing direct I/O for DIF type 2 (enabled: 0)
> +fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
> +Testing buffered I/O for DIF type 2 (enabled: 0)
> +fsx -N 10000 -l 500000
> +fsx -N 10000 -o 8192 -l 500000
> +fsx -N 10000 -o 32768 -l 500000
> +fsx -N 10000 -o 128000 -l 500000
> +Testing direct I/O for DIF type 3 (enabled: 0)
> +fsx -N 10000 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 8192 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 32768 -l 500000 -r BSIZE -w BSIZE -Z -R -W
> +fsx -N 10000 -o 128000 -l 500000 -r BSIZE -w BSIZE -Z -W
> +Testing buffered I/O for DIF type 3 (enabled: 0)
> +fsx -N 10000 -l 500000
> +fsx -N 10000 -o 8192 -l 500000
> +fsx -N 10000 -o 32768 -l 500000
> +fsx -N 10000 -o 128000 -l 500000
> -- 
> 2.53.0
> 
> 

Re: [PATCH 5/5] generic: test corruption detection using T10 protection information

[Darrick J. Wong]

On Fri, Aug 21, 2026 at 07:11:30AM +0200, Christoph Hellwig wrote:
> Add a test that simulates bit flips in data and misdirected writes and
> checks that file systems detect it when run on devices using protection
> information.
> 
> This requires the new scsi_debug corruption injection.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks good to me (this patch and the previous one), so
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

> ---
>  tests/generic/2302     | 128 +++++++++++++++++++++++++++++++++++++++++
>  tests/generic/2302.out |  21 +++++++
>  2 files changed, 149 insertions(+)
>  create mode 100755 tests/generic/2302
>  create mode 100644 tests/generic/2302.out
> 
> diff --git a/tests/generic/2302 b/tests/generic/2302
> new file mode 100755
> index 000000000000..4a9d9165174b
> --- /dev/null
> +++ b/tests/generic/2302
> @@ -0,0 +1,128 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2026 Christoph Hellwig
> +#
> +# FS QA Test No. 2302
> +#
> +# Test that T10 DIF detects bitflips and misplaced writes.
> +#
> +. ./common/preamble
> +_begin_fstest auto rw pi
> +
> +_cleanup()
> +{
> +	cd /
> +	rm -r -f $tmp.*
> +	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
> +	_put_scsi_debug_dev
> +}
> +
> +. ./common/scsi_debug
> +. ./common/filter
> +
> +_require_debugfs
> +_require_scsi_debug
> +# If TEST_DEV is block device, make sure current fs is a localfs which can be
> +# written on scsi_debug device
> +_require_test
> +_require_block_device $TEST_DEV
> +_require_xfs_io_command fiemap
> +_require_odirect
> +
> +# FIEMAP on Btrfs returns logical addresses within the filesystem's address
> +# space, not physical device offsets. Writing to these offsets on $SCRATCH_DEV
> +# would corrupt the filesystem in multi-device setups.
> +_exclude_fs btrfs
> +
> +size=$(_small_fs_size_mb 256)
> +
> +test_dif()
> +{
> +	local pi_type=$1
> +	local last=$2
> +	local bit_errors=$3
> +	local reftag_adjust=$4
> +
> +	echo -n "Testing DIF type $pi_type "
> +	if [ "$bit_errors" -gt "0" ]; then
> +		echo -n "bit errors ($bit_errors) in "
> +	fi
> +	if [ "$reftag_adjust" -ne "0" ]; then
> +		echo -n "reftag adjustment by $reftag_adjust in "
> +	fi
> +	if [ "$last" -eq 1 ]; then
> +		echo "last sector"
> +	else
> +		echo "first sector"
> +	fi
> +
> +	scsi_debug_pi_opts="write_same_length=0 dif=${pi_type} dix=1"
> +	SCSI_DEBUG_DEV=`_get_scsi_debug_dev 512 512 0 $size $scsi_debug_pi_opts`
> +
> +	SCSI_DEBUG_MNT="$TEST_DIR/scsi_debug_$seq"
> +	rm -rf $SCSI_DEBUG_MNT
> +	mkdir $SCSI_DEBUG_MNT
> +
> +	_mkfs_dev $SCSI_DEBUG_DEV || \
> +		_fail "Can't make $FSTYP on DIF-enabled scsi_debug device"
> +	run_check _mount $SCSI_DEBUG_DEV $SCSI_DEBUG_MNT
> +
> +	local blksz=$(_get_block_size $SCSI_DEBUG_MNT)
> +	local testfile="$SCSI_DEBUG_MNT/test"
> +
> +	$XFS_IO_PROG -d -f \
> +		-c "pwrite -S 0x66 0 $((128 * blksz))" \
> +		-c fsync \
> +		$testfile >> $seqres.full 2>&1
> +
> +	local phys_blk=$(_get_file_extent_sector $testfile 0)
> +	if [ -z "$phys_blk" ]; then
> +		_fail "$test_name: failed to get physical block offset via fiemap"
> +	fi
> +
> +	local dev=$(_short_dev $SCSI_DEBUG_DEV)
> +	local debugfs_dir=$(ls /sys/block/$dev/device/scsi_device/)
> +	local debugfs_file="/sys/kernel/debug/scsi_debug/$debugfs_dir/corrupt"
> +
> +	if [ ! -f "$debugfs_file" ]; then
> +		_notrun "scsi_debug corruption injection not supported"
> +	fi
> +
> +	if [ "$last" -eq 1 ]; then
> +		echo "adding to $phys_blk" >> $seqres.full
> +		phys_blk=$((phys_blk + 127))
> +	fi
> +
> +	echo "lba=$phys_blk,num=1,bit_errors=$bit_errors,reftag_adjust=$reftag_adjust" \
> +		 > $debugfs_file
> +
> +	$XFS_IO_PROG -d -f \
> +		-c "pread 0 $((128 * blksz))" \
> +		$testfile
> +
> +	[ -d "$SCSI_DEBUG_MNT" ] && _unmount $SCSI_DEBUG_MNT 2>/dev/null
> +	_put_scsi_debug_dev
> +}
> +
> +# test data corruption in first block
> +test_dif 1 0 2 0
> +test_dif 2 0 2 0
> +test_dif 3 0 2 0
> +
> +# test data corruption in last block
> +test_dif 1 1 2 0
> +test_dif 2 1 2 0
> +test_dif 3 1 2 0
> +
> +
> +# Note: Type 3 doesn't have a refrag, so don't test it
> +
> +# reftag mismatch in first block
> +test_dif 1 0 0 8
> +test_dif 2 0 0 8
> +
> +# reftag mismatch in last block
> +test_dif 1 1 0 8
> +test_dif 2 1 0 8
> +
> +_exit 0
> diff --git a/tests/generic/2302.out b/tests/generic/2302.out
> new file mode 100644
> index 000000000000..03b68d904943
> --- /dev/null
> +++ b/tests/generic/2302.out
> @@ -0,0 +1,21 @@
> +QA output created by 2302
> +Testing DIF type 1 bit errors (2) in first sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 2 bit errors (2) in first sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 3 bit errors (2) in first sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 1 bit errors (2) in last sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 2 bit errors (2) in last sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 3 bit errors (2) in last sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 1 reftag adjustment by 8 in first sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 2 reftag adjustment by 8 in first sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 1 reftag adjustment by 8 in last sector
> +pread: Invalid or incomplete multibyte or wide character
> +Testing DIF type 2 reftag adjustment by 8 in last sector
> +pread: Invalid or incomplete multibyte or wide character
> -- 
> 2.53.0
> 
>