Help needed in getting kernel dump in QEMU VM

Help needed in getting kernel dump in QEMU VM

[Dongliang Mu]

[-- Attachment #1: Type: text/plain, Size: 3365 bytes --]

Hi all KDUMP maintainers,

I would like to generate a kernel dump within QEMU VM.

1. I reproduced the kernel crash [1] in QEMU VM. The QEMU startup
script is as follows:

qemu-system-x86_64 \
  -kernel $KERNEL/arch/x86/boot/bzImage \
  -append "console=ttyS0 root=/dev/sda debug earlyprintk=serial slub_debug=QUZ"\
  -hda $IMAGE/stretch.img \
  -net user,hostfwd=tcp::10021-:22 -net nic \
  -enable-kvm \
  -nographic \
  -m 2G \
  -smp 2 \
  -pidfile vm.pid \
  2>&1 | tee vm.log

The stretch.img is generated by Syzkaller script [1]. -kernel option
is convenient for loading any other kernels.

2. As the .config already has the essential
configuration(CONFIG_KEXEC, CONFIG_CRASH_DUMP, CONFIG_DEBUG_INFO), I
did not change this configuration file.

3. I installed kdump-tools crash kexec-tools makedumpfile
linux-image-4.9.0-13-amd64 in the stretch.img. Here I installed
linux-image-4.9.0-13-amd64 because there is no default kernel in /boot
directory. And to make kdump-tools working, I modify
/etc/default/kdump-tools in the following:

KDUMP_INITRD=/boot/initrd.img-4.9.0-13-amd64
KDUMP_KERNEL=/boot/vmlinuz-4.9.0-13-amd64

4. I append "crashkernel=384M-:128M" to the command line in the
startup script of QEMU.

5. After rebooting, kdump service can start successfully, and the
kdump-config shows:

root@syzkaller:~# kdump-config show
DUMP_MODE:        kdump
USE_KDUMP:        1
KDUMP_SYSCTL:     kernel.panic_on_oops=1
KDUMP_COREDIR:    /var/crash
crashkernel addr: 0x77000000
   /boot/vmlinuz-4.9.0-13-amd64
kdump initrd:
   /boot/initrd.img-4.9.0-13-amd64
current state:    ready to kdump

kexec command:
  /sbin/kexec -p --command-line="earlyprintk=serial oops=panic
panic_on_warn=1 nmi_watchdog=panic panic=86400 net.ifnames=0
sysctl.kernel.hung_task_all_cpu_backtrace=1 ima_policy=tcb
kvm-intel.nested=1 nf-conntrack-ftp.ports=20000
nf-conntrack-tftp.ports=20000 nf-conntrack-sip.ports=20000
nf-conntrack-irc.ports=20000 nf-conntrack-sane.ports=20000
vivid.n_devs=16 vivid.multiplanar=1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2
netrom.nr_ndevs=16 rose.rose_ndevs=16 spec_store_bypass_disable=prctl
numa=fake=2 nopcid dummy_hcd.num=8 binder.debug_mask=0
rcupdate.rcu_expedited=1 root=/dev/sda console=ttyS0 vsyscall=native
watchdog_thresh=55 workqueue.watchdog_thresh=140 console=ttyS0
root=/dev/sda debug earlyprintk=serial slub_debug=QUZ irqpoll
nr_cpus=1 nousb systemd.unit=kdump-tools.service
ata_piix.prefer_ms_hyperv=0" --initrd=/boot/initrd.img-4.9.0-13-amd64
/boot/vmlinuz-4.9.0-13-amd64

6. When I execute the PoC, the current kernel crashes and then reboots
into the dump-capture kernel. However, the kernel log shows, it is in
emergency mode,

You are in emergency mode. After logging in, type "journalctl -xb" to view
system logs, "systemctl reboot" to reboot, "systemctl default" or ^D to
try again to boot into default mode.

Finally, I would like to ask several questions:
1) is the emergency mode due to the incorrect command line?
2) is this the right way to generate kernel dump from QEMU VM?
3) Any comments on the above procedures?

Thanks very much in advance.

[1] general protection fault in reiserfs_security_init
(https://syzkaller.appspot.com/bug?id=8abaedbdeb32c861dc5340544284167dd0e46cde)

[2] https://github.com/google/syzkaller/blob/master/tools/create-image.sh

--
My best regards to you.

     No System Is Safe!
     Dongliang Mu

[-- Attachment #2: log --]
[-- Type: application/octet-stream, Size: 4310 bytes --]

[  OK  ] Mounted POSIX Message Queue File System.
[  OK  ] Mounted Huge Pages File System.
[  OK  ] Mounted /sys/kernel/debug.
[  OK  ] Mounted /sys/kernel/config.
[  OK  ] Mounted /proc/sys/fs/binfmt_misc.
[  OK  ] Started Create Static Device Nodes in /dev.
[  OK  ] Started Load Kernel Modules.
[  OK  ] Started Remount Root and Kernel File Systems.
         Starting Load/Save Random Seed...
         Starting udev Coldplug all Devices...
         Mounting FUSE Control File System...
         Starting Apply Kernel Variables...
[  OK  ] Reached target Local File Systems (Pre).
         Starting udev Kernel Device Manager...
[  OK  ] Reached target Local File Systems.
[  OK  ] Mounted FUSE Control File System.
[  OK  ] Started Load/Save Random Seed.
[  OK  ] Started Apply Kernel Variables.
         Starting Raise network interfaces...
[  OK  ] Started udev Kernel Device Manager.
[  OK  ] Started Journal Service.
         Starting Flush Journal to Persistent Storage...
[  OK  ] Started Flush Journal to Persistent Storage.
         Starting Create Volatile Files and Directories...
[  OK  ] Started Create Volatile Files and Directories.
[   20.324774][   T20] e1000: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
[   20.331467][ T4801] 8021q: adding VLAN 0 to HW filter on device eth0
[   20.332426][   T20] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
         Starting Network Time Synchronization...
         Starting Update UTMP about System Boot/Shutdown...
[  OK  ] Started Update UTMP about System Boot/Shutdown.
[  OK  ] Started Network Time Synchronization.
[  OK  ] Reached target System Time Synchronized.
[  OK  ] Started Raise network interfaces.
[  OK  ] Reached target Network.
[  OK  ] Reached target Network is Online.
[  OK  ] Started udev Coldplug all Devices.
[  OK  ] Reached target System Initialization.
[  OK  ] Reached target Basic System.
[   40.833223][    C0] random: crng init done
[   40.833825][    C0] random: 7 urandom warning(s) missed due to ratelimiting
         Starting Kernel crash dump capture service...
         Starting OpenBSD Secure Shell server...
[  OK  ] Started irqbalance daemon.
[  OK  ] Started Daily Cleanup of Temporary Directories.
[  OK  ] Started Daily apt download activities.
[  OK  ] Started Daily apt upgrade and clean activities.
[  OK  ] Reached target Timers.
         Starting LSB: Execute the kexec -e command to reboot system...
[  OK  ] Started Regular background program processing daemon.
         Starting getty on tty2-tty6 if dbus and logind are not available...
         Starting Permit User Sessions...
         Starting System Logging Service...
[  OK  ] Started Permit User Sessions.
[  OK  ] Started System Logging Service.
[  OK  ] Started OpenBSD Secure Shell server.
[  OK  ] Started LSB: Execute the kexec -e command to reboot system.
[  OK  ] Started Getty on tty5.
[  OK  ] Started Getty on tty4.
[   43.594174] kdump-tools[7751]: Starting kdump-tools: Invalid symlink : /var/lib/kdump/initrd.img ... failed!
[   43.603486] kdump-tools[7751]: Creating symlink /var/lib/kdump/initrd.img.
[  OK  ] Started Getty on tty3.
[   43.705095] kdump-tools[7751]: Invalid symlink : /var/lib/kdump/vmlinuz ... failed!
[   43.711412] kdump-tools[7751]: Creating symlink /var/lib/kdump/vmlinuz.
         Starting LSB: Load kernel image with kexec...
[  OK  ] Started Getty on tty2.
[  OK  ] Started Getty on tty1.
[  OK  ] Started getty on tty2-tty6 if dbus and logind are not available.
[   45.163925][ T2795] blk_update_request: I/O error, dev fd0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
[   45.164995][ T2795] floppy: error 10 while reading block 0
[  OK  ] Started LSB: Load kernel image with kexec.
[  OK  ] Started Getty on tty6.
[  OK  ] Reached target Sound Card.
[   47.511332][ T7829] kexec (7829) used greatest stack depth: 22208 bytes left
[   47.501875] kdump-tools[7751]: loaded kdump kernel.
[  OK  ] Started Kernel crash dump capture service.
[  OK  ] Found device /dev/ttyS0.
[  OK  ] Started Serial Getty on ttyS0.
[  OK  ] Reached target Login Prompts.
[  OK  ] Reached target Multi-User System.
[  OK  ] Reached target Graphical Interface.
         Starting Update UTMP about System Runlevel Changes...
[  OK  ] Started Update UTMP about System Runlevel Changes.


[-- Attachment #3: Type: text/plain, Size: 170 bytes --]

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Re: Help needed in getting kernel dump in QEMU VM

[Baoquan He]

Hi,

On 11/13/21 at 10:40am, Dongliang Mu wrote:
> Hi all KDUMP maintainers,
> 
> I would like to generate a kernel dump within QEMU VM.
> 
> 1. I reproduced the kernel crash [1] in QEMU VM. The QEMU startup
> script is as follows:
> 
> qemu-system-x86_64 \
>   -kernel $KERNEL/arch/x86/boot/bzImage \
>   -append "console=ttyS0 root=/dev/sda debug earlyprintk=serial slub_debug=QUZ"\
>   -hda $IMAGE/stretch.img \
>   -net user,hostfwd=tcp::10021-:22 -net nic \
>   -enable-kvm \
>   -nographic \
>   -m 2G \
>   -smp 2 \
>   -pidfile vm.pid \
>   2>&1 | tee vm.log
> 
> The stretch.img is generated by Syzkaller script [1]. -kernel option
> is convenient for loading any other kernels.
> 
> 2. As the .config already has the essential
> configuration(CONFIG_KEXEC, CONFIG_CRASH_DUMP, CONFIG_DEBUG_INFO), I
> did not change this configuration file.
> 
> 3. I installed kdump-tools crash kexec-tools makedumpfile
> linux-image-4.9.0-13-amd64 in the stretch.img. Here I installed
> linux-image-4.9.0-13-amd64 because there is no default kernel in /boot
> directory. And to make kdump-tools working, I modify
> /etc/default/kdump-tools in the following:
> 
> KDUMP_INITRD=/boot/initrd.img-4.9.0-13-amd64
> KDUMP_KERNEL=/boot/vmlinuz-4.9.0-13-amd64

What distros are you using? Asking this because I am sure you are not
using Fedora/RHEL OS. The implementation of kdump tools is different in
each distros, even though the mechanims in kdump code is the same.

When we try to get help from upstream, considering and asking good question
is very important for getting quick response and effective help.

Thanks
Baoquan

> 
> 4. I append "crashkernel=384M-:128M" to the command line in the
> startup script of QEMU.
> 
> 5. After rebooting, kdump service can start successfully, and the
> kdump-config shows:
> 
> root@syzkaller:~# kdump-config show
> DUMP_MODE:        kdump
> USE_KDUMP:        1
> KDUMP_SYSCTL:     kernel.panic_on_oops=1
> KDUMP_COREDIR:    /var/crash
> crashkernel addr: 0x77000000
>    /boot/vmlinuz-4.9.0-13-amd64
> kdump initrd:
>    /boot/initrd.img-4.9.0-13-amd64
> current state:    ready to kdump
> 
> kexec command:
>   /sbin/kexec -p --command-line="earlyprintk=serial oops=panic
> panic_on_warn=1 nmi_watchdog=panic panic=86400 net.ifnames=0
> sysctl.kernel.hung_task_all_cpu_backtrace=1 ima_policy=tcb
> kvm-intel.nested=1 nf-conntrack-ftp.ports=20000
> nf-conntrack-tftp.ports=20000 nf-conntrack-sip.ports=20000
> nf-conntrack-irc.ports=20000 nf-conntrack-sane.ports=20000
> vivid.n_devs=16 vivid.multiplanar=1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2
> netrom.nr_ndevs=16 rose.rose_ndevs=16 spec_store_bypass_disable=prctl
> numa=fake=2 nopcid dummy_hcd.num=8 binder.debug_mask=0
> rcupdate.rcu_expedited=1 root=/dev/sda console=ttyS0 vsyscall=native
> watchdog_thresh=55 workqueue.watchdog_thresh=140 console=ttyS0
> root=/dev/sda debug earlyprintk=serial slub_debug=QUZ irqpoll
> nr_cpus=1 nousb systemd.unit=kdump-tools.service
> ata_piix.prefer_ms_hyperv=0" --initrd=/boot/initrd.img-4.9.0-13-amd64
> /boot/vmlinuz-4.9.0-13-amd64
> 
> 6. When I execute the PoC, the current kernel crashes and then reboots
> into the dump-capture kernel. However, the kernel log shows, it is in
> emergency mode,
> 
> You are in emergency mode. After logging in, type "journalctl -xb" to view
> system logs, "systemctl reboot" to reboot, "systemctl default" or ^D to
> try again to boot into default mode.
> 
> Finally, I would like to ask several questions:
> 1) is the emergency mode due to the incorrect command line?
> 2) is this the right way to generate kernel dump from QEMU VM?
> 3) Any comments on the above procedures?
> 
> Thanks very much in advance.
> 
> [1] general protection fault in reiserfs_security_init
> (https://syzkaller.appspot.com/bug?id=8abaedbdeb32c861dc5340544284167dd0e46cde)
> 
> [2] https://github.com/google/syzkaller/blob/master/tools/create-image.sh
> 
> --
> My best regards to you.
> 
>      No System Is Safe!
>      Dongliang Mu



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Re: Help needed in getting kernel dump in QEMU VM

[Dongliang Mu]

On Mon, Nov 15, 2021 at 3:27 PM Baoquan He <bhe@redhat.com> wrote:
>
> Hi,
>
> On 11/13/21 at 10:40am, Dongliang Mu wrote:
> > Hi all KDUMP maintainers,
> >
> > I would like to generate a kernel dump within QEMU VM.
> >
> > 1. I reproduced the kernel crash [1] in QEMU VM. The QEMU startup
> > script is as follows:
> >
> > qemu-system-x86_64 \
> >   -kernel $KERNEL/arch/x86/boot/bzImage \
> >   -append "console=ttyS0 root=/dev/sda debug earlyprintk=serial slub_debug=QUZ"\
> >   -hda $IMAGE/stretch.img \
> >   -net user,hostfwd=tcp::10021-:22 -net nic \
> >   -enable-kvm \
> >   -nographic \
> >   -m 2G \
> >   -smp 2 \
> >   -pidfile vm.pid \
> >   2>&1 | tee vm.log
> >
> > The stretch.img is generated by Syzkaller script [1]. -kernel option
> > is convenient for loading any other kernels.
> >
> > 2. As the .config already has the essential
> > configuration(CONFIG_KEXEC, CONFIG_CRASH_DUMP, CONFIG_DEBUG_INFO), I
> > did not change this configuration file.
> >
> > 3. I installed kdump-tools crash kexec-tools makedumpfile
> > linux-image-4.9.0-13-amd64 in the stretch.img. Here I installed
> > linux-image-4.9.0-13-amd64 because there is no default kernel in /boot
> > directory. And to make kdump-tools working, I modify
> > /etc/default/kdump-tools in the following:
> >
> > KDUMP_INITRD=/boot/initrd.img-4.9.0-13-amd64
> > KDUMP_KERNEL=/boot/vmlinuz-4.9.0-13-amd64
>
> What distros are you using? Asking this because I am sure you are not
> using Fedora/RHEL OS. The implementation of kdump tools is different in
> each distros, even though the mechanims in kdump code is the same.
>

I am using Debian stretch as the guest OS. So kdump-tools kexec
makedumpfile is all from Debian.

> When we try to get help from upstream, considering and asking good question
> is very important for getting quick response and effective help.
>
> Thanks
> Baoquan
>
> >
> > 4. I append "crashkernel=384M-:128M" to the command line in the
> > startup script of QEMU.
> >
> > 5. After rebooting, kdump service can start successfully, and the
> > kdump-config shows:
> >
> > root@syzkaller:~# kdump-config show
> > DUMP_MODE:        kdump
> > USE_KDUMP:        1
> > KDUMP_SYSCTL:     kernel.panic_on_oops=1
> > KDUMP_COREDIR:    /var/crash
> > crashkernel addr: 0x77000000
> >    /boot/vmlinuz-4.9.0-13-amd64
> > kdump initrd:
> >    /boot/initrd.img-4.9.0-13-amd64
> > current state:    ready to kdump
> >
> > kexec command:
> >   /sbin/kexec -p --command-line="earlyprintk=serial oops=panic
> > panic_on_warn=1 nmi_watchdog=panic panic=86400 net.ifnames=0
> > sysctl.kernel.hung_task_all_cpu_backtrace=1 ima_policy=tcb
> > kvm-intel.nested=1 nf-conntrack-ftp.ports=20000
> > nf-conntrack-tftp.ports=20000 nf-conntrack-sip.ports=20000
> > nf-conntrack-irc.ports=20000 nf-conntrack-sane.ports=20000
> > vivid.n_devs=16 vivid.multiplanar=1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2
> > netrom.nr_ndevs=16 rose.rose_ndevs=16 spec_store_bypass_disable=prctl
> > numa=fake=2 nopcid dummy_hcd.num=8 binder.debug_mask=0
> > rcupdate.rcu_expedited=1 root=/dev/sda console=ttyS0 vsyscall=native
> > watchdog_thresh=55 workqueue.watchdog_thresh=140 console=ttyS0
> > root=/dev/sda debug earlyprintk=serial slub_debug=QUZ irqpoll
> > nr_cpus=1 nousb systemd.unit=kdump-tools.service
> > ata_piix.prefer_ms_hyperv=0" --initrd=/boot/initrd.img-4.9.0-13-amd64
> > /boot/vmlinuz-4.9.0-13-amd64
> >
> > 6. When I execute the PoC, the current kernel crashes and then reboots
> > into the dump-capture kernel. However, the kernel log shows, it is in
> > emergency mode,
> >
> > You are in emergency mode. After logging in, type "journalctl -xb" to view
> > system logs, "systemctl reboot" to reboot, "systemctl default" or ^D to
> > try again to boot into default mode.
> >
> > Finally, I would like to ask several questions:
> > 1) is the emergency mode due to the incorrect command line?
> > 2) is this the right way to generate kernel dump from QEMU VM?
> > 3) Any comments on the above procedures?
> >
> > Thanks very much in advance.
> >
> > [1] general protection fault in reiserfs_security_init
> > (https://syzkaller.appspot.com/bug?id=8abaedbdeb32c861dc5340544284167dd0e46cde)
> >
> > [2] https://github.com/google/syzkaller/blob/master/tools/create-image.sh
> >
> > --
> > My best regards to you.
> >
> >      No System Is Safe!
> >      Dongliang Mu
>
>

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Kernelnewbies@kernelnewbies.org
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Re: Help needed in getting kernel dump in QEMU VM

[Baoquan He]

On 11/15/21 at 03:49pm, Dongliang Mu wrote:
> On Mon, Nov 15, 2021 at 3:27 PM Baoquan He <bhe@redhat.com> wrote:
> >
> > Hi,
> >
> > On 11/13/21 at 10:40am, Dongliang Mu wrote:
> > > Hi all KDUMP maintainers,
> > >
> > > I would like to generate a kernel dump within QEMU VM.
> > >
> > > 1. I reproduced the kernel crash [1] in QEMU VM. The QEMU startup
> > > script is as follows:
> > >
> > > qemu-system-x86_64 \
> > >   -kernel $KERNEL/arch/x86/boot/bzImage \
> > >   -append "console=ttyS0 root=/dev/sda debug earlyprintk=serial slub_debug=QUZ"\
> > >   -hda $IMAGE/stretch.img \
> > >   -net user,hostfwd=tcp::10021-:22 -net nic \
> > >   -enable-kvm \
> > >   -nographic \
> > >   -m 2G \
> > >   -smp 2 \
> > >   -pidfile vm.pid \
> > >   2>&1 | tee vm.log
> > >
> > > The stretch.img is generated by Syzkaller script [1]. -kernel option
> > > is convenient for loading any other kernels.
> > >
> > > 2. As the .config already has the essential
> > > configuration(CONFIG_KEXEC, CONFIG_CRASH_DUMP, CONFIG_DEBUG_INFO), I
> > > did not change this configuration file.
> > >
> > > 3. I installed kdump-tools crash kexec-tools makedumpfile
> > > linux-image-4.9.0-13-amd64 in the stretch.img. Here I installed
> > > linux-image-4.9.0-13-amd64 because there is no default kernel in /boot
> > > directory. And to make kdump-tools working, I modify
> > > /etc/default/kdump-tools in the following:
> > >
> > > KDUMP_INITRD=/boot/initrd.img-4.9.0-13-amd64
> > > KDUMP_KERNEL=/boot/vmlinuz-4.9.0-13-amd64
> >
> > What distros are you using? Asking this because I am sure you are not
> > using Fedora/RHEL OS. The implementation of kdump tools is different in
> > each distros, even though the mechanims in kdump code is the same.
> >
> 
> I am using Debian stretch as the guest OS. So kdump-tools kexec
> makedumpfile is all from Debian.

Then I would sugest asking in a Debian/ubuntu forum or mailing list, figure
out if the configuration or setting is correct. 

I never try Debian OS, can't help, sorry.

> 
> > When we try to get help from upstream, considering and asking good question
> > is very important for getting quick response and effective help.
> >
> > Thanks
> > Baoquan
> >
> > >
> > > 4. I append "crashkernel=384M-:128M" to the command line in the
> > > startup script of QEMU.
> > >
> > > 5. After rebooting, kdump service can start successfully, and the
> > > kdump-config shows:
> > >
> > > root@syzkaller:~# kdump-config show
> > > DUMP_MODE:        kdump
> > > USE_KDUMP:        1
> > > KDUMP_SYSCTL:     kernel.panic_on_oops=1
> > > KDUMP_COREDIR:    /var/crash
> > > crashkernel addr: 0x77000000
> > >    /boot/vmlinuz-4.9.0-13-amd64
> > > kdump initrd:
> > >    /boot/initrd.img-4.9.0-13-amd64
> > > current state:    ready to kdump
> > >
> > > kexec command:
> > >   /sbin/kexec -p --command-line="earlyprintk=serial oops=panic
> > > panic_on_warn=1 nmi_watchdog=panic panic=86400 net.ifnames=0
> > > sysctl.kernel.hung_task_all_cpu_backtrace=1 ima_policy=tcb
> > > kvm-intel.nested=1 nf-conntrack-ftp.ports=20000
> > > nf-conntrack-tftp.ports=20000 nf-conntrack-sip.ports=20000
> > > nf-conntrack-irc.ports=20000 nf-conntrack-sane.ports=20000
> > > vivid.n_devs=16 vivid.multiplanar=1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2
> > > netrom.nr_ndevs=16 rose.rose_ndevs=16 spec_store_bypass_disable=prctl
> > > numa=fake=2 nopcid dummy_hcd.num=8 binder.debug_mask=0
> > > rcupdate.rcu_expedited=1 root=/dev/sda console=ttyS0 vsyscall=native
> > > watchdog_thresh=55 workqueue.watchdog_thresh=140 console=ttyS0
> > > root=/dev/sda debug earlyprintk=serial slub_debug=QUZ irqpoll
> > > nr_cpus=1 nousb systemd.unit=kdump-tools.service
> > > ata_piix.prefer_ms_hyperv=0" --initrd=/boot/initrd.img-4.9.0-13-amd64
> > > /boot/vmlinuz-4.9.0-13-amd64
> > >
> > > 6. When I execute the PoC, the current kernel crashes and then reboots
> > > into the dump-capture kernel. However, the kernel log shows, it is in
> > > emergency mode,
> > >
> > > You are in emergency mode. After logging in, type "journalctl -xb" to view
> > > system logs, "systemctl reboot" to reboot, "systemctl default" or ^D to
> > > try again to boot into default mode.
> > >
> > > Finally, I would like to ask several questions:
> > > 1) is the emergency mode due to the incorrect command line?
> > > 2) is this the right way to generate kernel dump from QEMU VM?
> > > 3) Any comments on the above procedures?
> > >
> > > Thanks very much in advance.
> > >
> > > [1] general protection fault in reiserfs_security_init
> > > (https://syzkaller.appspot.com/bug?id=8abaedbdeb32c861dc5340544284167dd0e46cde)
> > >
> > > [2] https://github.com/google/syzkaller/blob/master/tools/create-image.sh
> > >
> > > --
> > > My best regards to you.
> > >
> > >      No System Is Safe!
> > >      Dongliang Mu
> >
> >
> 


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