Bug#929531: grub-pc: grub2 fat_test fails with 4.19.0-5-amd64 kernel if one ensure it does not gets auto-skipped

Sat May 25 20:50:33 BST 2019

Package: grub-pc
Version: 2.02+dfsg1-18
Severity: serious
Tags: ftbfs
Justification: fails to build from source (but built successfully in the past)

Dear Maintainer,

while grub2 build fine as common users, i.e., the one created by the
Debian Installer with the addition that it's added to the 'kvm' group,
it does currently not as root depending on the Linux Kernel booted as
with some the fat_test fail.

Reproducer:

* installing Debian from recent weekly testing ISO, boot, install
  build-essentials and devscripts
* # uname -a
  Linux bussard 4.19.0-5-amd64 #1 SMP Debian 4.19.37-3 (2019-05-15)
  x86_64 GNU/Linux
* # apt source grub2
* # apt buil-dep grub2
* # cd grub2-2.02+dfsg1/
* # debuild -b -uc -us
  ...
   mkdir: cannot create directory
   ‘/tmp/tmp.gfJAxp7sgv/vfat12a_rw///0//1/2/3//4/5’: Input/output error

  (full test-suite.log inlined below)

kernel logged:
> May 25 20:27:51 bussard kernel: FAT-fs (loop0): error, corrupted directory (invalid entries)
> May 25 20:27:51 bussard kernel: FAT-fs (loop0): Filesystem has been set read-only
> May 25 20:27:51 bussard kernel: FAT-fs (loop0): error, fat_get_cluster: invalid cluster chain (i_pos 0)

I tried multiple times, most of them with a reboot plus a complete
cleanup and re-download of the source inbetween, but did not always saw
the same error, different directories

As I had build this in the past sucessfully I was a bit thrown-off
first, reverting back to and older Kernel (first one I had lying arround
was linux-image-4.16.0-1-amd64) it worked again, and build successfully.

So, IMHO, there's an issue with either VFAT in the kernel itself, or how
GRUB2 (test) uses VFAT under current Kernels, which just does not shows
up as those FS test get skipped as common, unpriviledged, user, as the
mkfs and loop device handling is normally not allowed for them.

While yes, building as root is far from nice, it's the simplest way to
actually ensure those FS test get run and thus show up an issue.

I tested out some Kernels, most from the Ubuntu Mainline kernel ppa:
https://kernel.ubuntu.com/~kernel-ppa/mainline/

I had varying results, it seems that 4.19.1-041901-generic always
worked, but 4.19.37-041937-generic worked once, then on two different
VMs I got errors too, so a bit strange, a 4.19.28-041928-generic failed
to here, I did not invest more time into bisectin the issue because I
had not much available and was a bit confused by the behaviour..

Below the test-suite log output. I hope I got this to the correct
package people, as may have suited better on the kernel package, but as
I only could trigger this by building grub with the test running I
choose to initially report it here, sorry if it wasn't correct.

### BEGIN /root/grub2-2.02+dfsg1/obj/grub-pc/test-suite.log ###
==========================================
   GRUB 2.02+dfsg1-18: ./test-suite.log
   ==========================================

   # TOTAL: 81
   # PASS:  63
   # SKIP:  17
   # XFAIL: 0
   # FAIL:  1
   # XPASS: 0
   # ERROR: 0

   .. contents:: :depth: 2

   SKIP: squashfs_test
   ===================

   mksquashfs not installed; cannot test squashfs.

   SKIP: hfsplus_test
   ==================

   mkfs.hfsplus not installed; cannot test hfsplus.

   SKIP: ntfs_test
   ===============

   mkfs.ntfs not installed; cannot test ntfs.

   SKIP: reiserfs_test
   ===================

   mkfs.reiserfs not installed; cannot test reiserfs.

   FAIL: fat_test
   ==============

   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 30000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.wcIfohU4Fn/vfat16a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 30000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.wcIfohU4Fn/vfat16a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 60000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.wcIfohU4Fn/vfat16a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 120000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.wcIfohU4Fn/vfat16a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 240000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.wcIfohU4Fn/vfat16a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 1500KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 3000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 5000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 10000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 20000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 30000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 3000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 5000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 10000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 20000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 40000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 60000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 5000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 10000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 20000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 40000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   Device proc: Filesystem type procfs - Sector size 512B - Total size
   0KiB
   Device loop0: Filesystem type fat - Label `GRUBTEST ;_', UUID
   0000-0000 - Sector size 512B - Total size 80000KiB
   Device host: Filesystem type hostfs - Sector size 512B - Total size
   0KiB

   umount: /tmp/tmp.gfJAxp7sgv/vfat12a_rw: not mounted.
   mkfs.fat 4.1 (2017-01-24)
   Warning: More than 32765 sector need TOS 1.04 or higher.
   mkdir: cannot create directory
   ‘/tmp/tmp.gfJAxp7sgv/vfat12a_rw///0//1/2/3//4/5’: Input/output error

   SKIP: minixfs_test
   ==================

   mkfs.minix doesn't support variable block size; cannot test minix*fs.

   SKIP: xfs_test
   ==============

   mkfs.xfs not installed; cannot test xfs.

   SKIP: nilfs2_test
   =================

   mkfs.nilfs2 not installed; cannot test nilfs2.

   SKIP: romfs_test
   ================

   genromfs not installed; cannot test romfs.

   SKIP: exfat_test
   ================

   mkfs.exfat not installed; cannot test exFAT.

   SKIP: udf_test
   ==============

   mkudffs not installed; cannot test UDF.

   SKIP: hfs_test
   ==============

   mkfs.hfs not installed; cannot test HFS.

   SKIP: jfs_test
   ==============

   mkfs.jfs not installed; cannot test JFS.

   SKIP: btrfs_test
   ================

   mkfs.btrfs not installed; cannot test btrfs.

   SKIP: zfs_test
   ==============

   zpool not installed; cannot test zfs.

   SKIP: gettext_strings_test
   ==========================

   Skipping upstream maintenance check.

   SKIP: grub_cmd_set_date
   =======================

   Skipping flaky test.

   SKIP: lzocompress_test
   ======================

   lzop not installed; cannot test lzo compression.

### END /root/grub2-2.02+dfsg1/obj/grub-pc/test-suite.log ###

-- Package-specific info:

*********************** BEGIN /proc/mounts
/dev/sda1 / ext4 rw,relatime,errors=remount-ro 0 0
/dev/loop0 /tmp/tmp.gfJAxp7sgv/vfat12a_rw vfat ro,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=utf8,shortname=mixed,utf8,errors=remount-ro 0 0
*********************** END /proc/mounts

*********************** BEGIN /boot/grub/grub.cfg
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
  set have_grubenv=true
  load_env
fi
if [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
else
  menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}
function load_video {
  if [ x$feature_all_video_module = xy ]; then
    insmod all_video
  else
    insmod efi_gop
    insmod efi_uga
    insmod ieee1275_fb
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
  fi
}

if [ x$feature_default_font_path = xy ] ; then
   font=unicode
else
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1  ccff1e50-b5e2-46c0-9976-d97e7c47b10d
else
  search --no-floppy --fs-uuid --set=root ccff1e50-b5e2-46c0-9976-d97e7c47b10d
fi
    font="/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
  set locale_dir=$prefix/locale
  set lang=en_US
  insmod gettext
fi
terminal_output gfxterm
if [ "${recordfail}" = 1 ] ; then
  set timeout=30
else
  if [ x$feature_timeout_style = xy ] ; then
    set timeout_style=menu
    set timeout=5
  # Fallback normal timeout code in case the timeout_style feature is
  # unavailable.
  else
    set timeout=5
  fi
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=cyan/blue
set menu_color_highlight=white/blue
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
function gfxmode {
	set gfxpayload="${1}"
}
set linux_gfx_mode=
export linux_gfx_mode
menuentry 'Debian GNU/Linux' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-ccff1e50-b5e2-46c0-9976-d97e7c47b10d' {
	load_video
	insmod gzio
	if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
	insmod part_msdos
	insmod ext2
	set root='hd0,msdos1'
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1  ccff1e50-b5e2-46c0-9976-d97e7c47b10d
	else
	  search --no-floppy --fs-uuid --set=root ccff1e50-b5e2-46c0-9976-d97e7c47b10d
	fi
	echo	'Loading Linux 4.19.0-5-amd64 ...'
	linux	/boot/vmlinuz-4.19.0-5-amd64 root=UUID=ccff1e50-b5e2-46c0-9976-d97e7c47b10d ro  quiet
	echo	'Loading initial ramdisk ...'
	initrd	/boot/initrd.img-4.19.0-5-amd64
}
submenu 'Advanced options for Debian GNU/Linux' $menuentry_id_option 'gnulinux-advanced-ccff1e50-b5e2-46c0-9976-d97e7c47b10d' {
	menuentry 'Debian GNU/Linux, with Linux 4.19.0-5-amd64' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.19.0-5-amd64-advanced-ccff1e50-b5e2-46c0-9976-d97e7c47b10d' {
		load_video
		insmod gzio
		if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
		insmod part_msdos
		insmod ext2
		set root='hd0,msdos1'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1  ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		else
		  search --no-floppy --fs-uuid --set=root ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		fi
		echo	'Loading Linux 4.19.0-5-amd64 ...'
		linux	/boot/vmlinuz-4.19.0-5-amd64 root=UUID=ccff1e50-b5e2-46c0-9976-d97e7c47b10d ro  quiet
		echo	'Loading initial ramdisk ...'
		initrd	/boot/initrd.img-4.19.0-5-amd64
	}
	menuentry 'Debian GNU/Linux, with Linux 4.19.0-5-amd64 (recovery mode)' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.19.0-5-amd64-recovery-ccff1e50-b5e2-46c0-9976-d97e7c47b10d' {
		load_video
		insmod gzio
		if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
		insmod part_msdos
		insmod ext2
		set root='hd0,msdos1'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1  ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		else
		  search --no-floppy --fs-uuid --set=root ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		fi
		echo	'Loading Linux 4.19.0-5-amd64 ...'
		linux	/boot/vmlinuz-4.19.0-5-amd64 root=UUID=ccff1e50-b5e2-46c0-9976-d97e7c47b10d ro single 
		echo	'Loading initial ramdisk ...'
		initrd	/boot/initrd.img-4.19.0-5-amd64
	}
	menuentry 'Debian GNU/Linux, with Linux 4.19.0-4-amd64' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.19.0-4-amd64-advanced-ccff1e50-b5e2-46c0-9976-d97e7c47b10d' {
		load_video
		insmod gzio
		if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
		insmod part_msdos
		insmod ext2
		set root='hd0,msdos1'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1  ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		else
		  search --no-floppy --fs-uuid --set=root ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		fi
		echo	'Loading Linux 4.19.0-4-amd64 ...'
		linux	/boot/vmlinuz-4.19.0-4-amd64 root=UUID=ccff1e50-b5e2-46c0-9976-d97e7c47b10d ro  quiet
		echo	'Loading initial ramdisk ...'
		initrd	/boot/initrd.img-4.19.0-4-amd64
	}
	menuentry 'Debian GNU/Linux, with Linux 4.19.0-4-amd64 (recovery mode)' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.19.0-4-amd64-recovery-ccff1e50-b5e2-46c0-9976-d97e7c47b10d' {
		load_video
		insmod gzio
		if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
		insmod part_msdos
		insmod ext2
		set root='hd0,msdos1'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1  ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		else
		  search --no-floppy --fs-uuid --set=root ccff1e50-b5e2-46c0-9976-d97e7c47b10d
		fi
		echo	'Loading Linux 4.19.0-4-amd64 ...'
		linux	/boot/vmlinuz-4.19.0-4-amd64 root=UUID=ccff1e50-b5e2-46c0-9976-d97e7c47b10d ro single 
		echo	'Loading initial ramdisk ...'
		initrd	/boot/initrd.img-4.19.0-4-amd64
	}
}

### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###

### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/30_os-prober ###
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/30_uefi-firmware ###
### END /etc/grub.d/30_uefi-firmware ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f  ${config_directory}/custom.cfg ]; then
  source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f  $prefix/custom.cfg ]; then
  source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###
*********************** END /boot/grub/grub.cfg

*********************** BEGIN /proc/mdstat
cat: /proc/mdstat: No such file or directory
*********************** END /proc/mdstat

*********************** BEGIN /dev/disk/by-id
total 0
lrwxrwxrwx 1 root root  9 May 25 18:30 ata-QEMU_DVD-ROM_QM00003 -> ../../sr0
lrwxrwxrwx 1 root root  9 May 25 18:30 scsi-0QEMU_QEMU_HARDDISK_drive-scsi0 -> ../../sda
lrwxrwxrwx 1 root root 10 May 25 18:30 scsi-0QEMU_QEMU_HARDDISK_drive-scsi0-part1 -> ../../sda1
*********************** END /dev/disk/by-id

*********************** BEGIN /dev/disk/by-uuid
total 0
lrwxrwxrwx 1 root root  9 May 25 18:30 2019-05-16-09-22-57-00 -> ../../sr0
lrwxrwxrwx 1 root root 10 May 25 18:30 ccff1e50-b5e2-46c0-9976-d97e7c47b10d -> ../../sda1
*********************** END /dev/disk/by-uuid

-- System Information:
Debian Release: 10.0
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.19.0-5-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en (charmap=UTF-8)
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages grub-pc depends on:
ii  debconf [debconf-2.0]  1.5.71
ii  grub-common            2.02+dfsg1-18
ii  grub-pc-bin            2.02+dfsg1-18
ii  grub2-common           2.02+dfsg1-18
ii  ucf                    3.0038+nmu1

grub-pc recommends no packages.

grub-pc suggests no packages.

-- debconf information excluded