Rewrite kdumpctl reset-crashkernel KERNEL_PATH as
kdumpctl reset-crashkernel [--fadump=[on|off|nocma]] [--kernel=path_to_kernel] [--reboot]
This interface would reset a specific kernel to the default crashkernel value
given the kernel path. And it also supports grubby's syntax so there are the
following special cases,
- if --kernel not specified,
- use KDUMP_KERNELVER if it's defined in /etc/sysconfig/kdump
- otherwise use current running kernel, i.e. `uname -r`
- if --kernel=DEFAULT, the default boot kernel is chosen
- if --kernel=ALL, all kernels would have its crashkernel reset to the
default value and the /etc/default/grub is updated as well
--fadump=[on|off|nocma] toggles fadump on/off for the kernel provided
in KERNEL_PATH. If --fadump is omitted, the dump mode is determined by
parsing the kernel command line for the kernel(s) to update.
CoreOS/Atomic/Silverblue needs to be treated as a special case because,
- "rpm-ostree kargs" is used to manage kernel command line parameters
so --kernel doesn't make sense and there is no need to find current
running kernel
- "rpm-ostree kargs" itself would prompt the user to reboot the system
after modify the kernel command line parameter
- POWER is not supported so we can assume the dump mode is always kdump
This interface will also be called by kexec-tools RPM scriptlets [1]
to reset crashkernel.
Note the support of crashkenrel.default is dropped.
[1] https://docs.fedoraproject.org/en-US/packaging-guidelines/Scriptlets/
Reviewed-by: Pingfan Liu <piliu@redhat.com>
Reviewed-by: Philipp Rudo <prudo@redhat.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>
In newer kernel, crashkernel.default will contain the default
crashkernel value of a kernel build. So introduce a new sub command
to help user reset kernel crashkernel size to the default value.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Add a rough esitimation support, currently, following memory usage are
checked by this sub command:
- System RAM
- Kdump Initramfs size
- Kdump Kernel image size
- Kdump Kernel module size
- Kdump userspace user and other runtime allocated memory (currently
simply using a fixed value: 64M)
- LUKS encryption memory usage
The output of kdumpctl estimate looks like this:
# kdumpctl estimate
Reserved crashkernel: 256M
Recommanded crashkernel: 160M
Kernel image size: 47M
Kernel modules size: 12M
Initramfs size: 19M
Runtime reservation: 64M
Large modules:
xfs: 1892352
nouveau: 2318336
And if the kdump target is encrypted:
# kdumpctl estimate
Encrypted kdump target requires extra memory, assuming using the keyslot with minimun memory requirement
Reserved crashkernel: 256M
Recommanded crashkernel: 655M
Kernel image size: 47M
Kernel modules size: 12M
Initramfs size: 19M
Runtime reservation: 64M
LUKS required size: 512M
Large modules:
xfs: 1892352
nouveau: 2318336
WARNING: Current crashkernel size is lower than recommanded size 655M.
The "Recommanded" value is calculated based on memory usages mentioned
above, and will be adjusted accodingly to be no less than the value provided
by kdump_get_arch_recommend_size.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
These two command are not documented, update the man page to let user
know how to use them.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
port from rhel, original patch is contributed by Minfei Huang:
Using /sys to determines crashkernel actual size is confusing since
there is no unit of measure.
Add a new command "kdumpctl showmem" to show the reserved memory kindly.
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Signed-off-by: Minfei Huang <mhuang@redhat.com>
Acked-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
kdumpctl is useful sometimes when users want to debug or setup ssh key
authentication. So add a man page for it.
Signed-off-by: Dangyi Liu <dliu@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Pratyush Anand <panand@redhat.com>
Coiby Xu
Kairui Song
Pingfan Liu
Dangyi Liu