Dracut get_persistent_dev function don't recognize UUID= or LABEL=
format, so caller should conver it to the path to the block device
before calling it. There is already such a helper
"kdump_get_persistent_dev", just move it to kdump-lib.sh and rename
it to reuse it,
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
This patch adds the binary and script files in /etc/kdump/{pre.d,post.d}
to modified checklist in order to update kdump initramfs when one adds
new scripts or binaries or removes the existing ones under
/etc/kdump/{pre.d, post.d}.
Signed-off-by: Shinichi Onitsuka <onitsuka.shinic@fujitsu.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
Use get_mount_info so that fstab is used as a failback when look for
mount info.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
Ignore mount check in kdumpctl, mkdumprd will still fail building and
exit if target is not mounted.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
Use is_mounted helper instaed of calling findmnt directly or checking if
"mount" value is empty.
If findmnt looks for fstab as well, some non mounted entry will also
return value. Required to support non-mounted target.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
User a helper to get the path to mount dump target in kdump kernel, and
fix duplicated '/' in the mount path problem.
Fixes: bz1785371
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
It's basically same with is_user_configured_dump_target and only have
one caller. And the name is confusing, the dump target is always
configured, it's either user configured or path based.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Lianbo Jiang <lijiang@redhat.com>
Now modinfo will return "(builtin)" instead of empty string for builtin
module. Sync the code logic.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
Since Dracut commit a0d9ad6 loaded-kernel-modules is renamed to
hostonly-kernel-modules and contains all hostonly modules. So check
hostonly-kernel-modules instead for module change.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
With FADump support added on POWERNV paltform, enable the scripts to
capture /proc/vmcore. Also, if CONFIG_OPAL_CORE is enabled, OPAL core
is preserved and exported on POWERNV platform. So, offload OPAL core,
if it is available.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Kairui Song <kasong@redhat.com>
UEFI Secure boot is a signature verification mechanism, designed to
prevent malicious code being loaded and executed at the early boot
stage. This makes sure that code executed is trusted by firmware.
Previously, with kexec_file_load() interface, kernel prevents unsigned
kernel image from being loaded if secure boot is enabled. So kdump will
detect whether secure boot is enabled firstly, then decide which interface
is chosen to execute, kexec_load() or kexec_file_load(). Otherwise unsigned
kernel loading will fail if secure boot enabled, and kexec_file_load() is
entered.
Now, the implementation of kexec_file_load() is adjusted in below commit.
With this change, if CONFIG_KEXEC_SIG_FORCE is not set, unsigned kernel
still has a chance to be allowed to load under some conditions.
commit 99d5cadfde2b ("kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG
and KEXEC_SIG_FORCE")
And in the current Fedora, the CONFIG_KEXEC_SIG_FORCE is not set, only the
CONFIG_KEXEC_SIG and CONFIG_BZIMAGE_VERIFY_SIG are set on x86_64 by default.
It's time to spread kexec_file_load() onto all systems of x86_64, including
Secure-boot platforms and legacy platforms. Please refer to the following
form.
.----------------------------------------------------------------------.
| . | signed kernel | unsigned kernel |
| . types |-----------------------|-----------------------|
| . |Secure boot| Legacy |Secure boot| Legacy |
| . |-----------|-----------|-----------|-----------|
| options . | prev| now | prev| now | | | prev| now |
| . |(file|(file|(only|(file| prev| now |(only|(file|
| . |load)|load)|load)|load)| | |load)|load)|
|----------------------|-----|-----|-----|-----|-----|-----|-----|-----|
|KEXEC_SIG=y | | | | | | | | |
|SIG_FORCE is not set |succ |succ |succ |succ | X | X |succ |succ |
|BZIMAGE_VERIFY_SIG=y | | | | | | | | |
|----------------------|-----|-----|-----|-----|-----|-----|-----|-----|
|KEXEC_SIG=y | | | | | | | | |
|SIG_FORCE is not set | | | | | | | | |
|BZIMAGE_VERIFY_SIG is |fail |fail |succ |fail | X | X |succ |fail |
|not set | | | | | | | | |
|----------------------|-----|-----|-----|-----|-----|-----|-----|-----|
|KEXEC_SIG=y | | | | | | | | |
|SIG_FORCE=y |succ |succ |succ |fail | X | X |succ |fail |
|BZIMAGE_VERIFY_SIG=y | | | | | | | | |
|----------------------|-----|-----|-----|-----|-----|-----|-----|-----|
|KEXEC_SIG=y | | | | | | | | |
|SIG_FORCE=y | | | | | | | | |
|BZIMAGE_VERIFY_SIG is |fail |fail |succ |fail | X | X |succ |fail |
|not set | | | | | | | | |
|----------------------|-----|-----|-----|-----|-----|-----|-----|-----|
|KEXEC_SIG is not set | | | | | | | | |
|SIG_FORCE is not set | | | | | | | | |
|BZIMAGE_VERIFY_SIG is |fail |fail |succ |succ | X | X |succ |succ |
|not set | | | | | | | | |
----------------------------------------------------------------------
Note:
[1] The 'X' indicates that the 1st kernel(unsigned) can not boot when the
Secure boot is enabled.
Hence, in this patch, if on x86_64, let's use the kexec_file_load() only.
See if anything wrong happened in this case, in Fedora firstly for the
time being.
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
When large amount of memory, about 1TB, is removed with DLPAR memory
remove operation, kdump reload could fail due to race condition with
device tree property update. In such scenario, the subsequent kdump
reload requests would also fail as reload() only proceeds if current
load status is active. Since the possibility of this race condition
couldn't be wished away due to the nature of the scenario, workaround
it by proceeding to load even if current load status is not active as
long as kdump service is active, which kdump udev rules already check
for.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Kairui Song <kasong@redhat.com>
In kdump.conf, if sshkey points to an invalid ssh key, 'kdumpctl restart'
can bail out immediately instead of retry.
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
Print some message during the long wait period to reflect the process.
The message will look like:
Network dump target is not usable, waiting for it to be ready
...
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
On a host with ipaddr not ready before kdump service, ssh return errno 255.
While if no ssh-key, ssh also return errno 255. For both of cases, the
current kdump code promote user to run 'kdumpctl propagate'. This confuses
user who already installs ssh-key.
In order to tell these two cases from each other, the ssh warning message
should be involved, and parsed.
For the no ssh-key case , warning message is "Permission denied" or "No
such file or directory". For the other, warning message is "Network
Unreachable"
This patch also does a slight change to enlarge the timeout from 60s to
180s. This value can meet test at the time being
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
If dump target is ipv6 address, a host should have ipv6 address ready
before starting kdump service. Otherwise, kdump service fails to start due
to the failure "ssh dump_server_ip mkdir -p $SAVE_PATH".
And user can see message like:
"Could not create root@2620:52:0:10da:46a8:42ff:fe23:3272/var/crash"
I observe a long period (about 30s) on some machine before they got ipv6
address dynamiclly, which is never seen on ipv4 host.
Hence kdump service has a dependency on ipv6 address. But there is no good
way to resolve it. One way is asking user to run the cmd "nmcli connection
modify eth0 ipv6.may-fail false". But this will block systemd until ipv6
address is ready. Despite doing so, kdump can try its best (wait 1 minutes
after it starts up) before failure.
How to implement the wait is arguable. It will involve too many technique
details if explicitly waiting on ipv6 address, instead, just lean on 'ssh'
return value to see the availability of network.
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
Currently kdumpctl rebuild will simply rebuild the initramfs, and
only perform basic config syntax check. But it should also check if the
target path is available when using SSH target, else kdump may fail.
is second kernel. kdumpctl rebuild should cover this case, and create
the path if it doesn't exist.
This patch make rebuild and restart behaves the same, rebuild is
now equal to restart, except it won't check config change or reload
kdump resource.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Although "kdumpctl rebuild" is introduced to help user rebuild the
initramfs without modifying the kdump.conf, if the kdump.conf is
modified and "kdumpctl rebuild" is called, a initramfs with a faulty
kdump.conf will be built.
Kdump will refuse to load the initramfs when restarted, but kdumpctl
reload may load the faulty initramfs. So need to make sure the faulty
build won't be generate in the first place.
Check for kdump.conf error before building the initramfs to ensure such
failure won't happen.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
We don't necessarily have to always rebuild the initramfs when
extra_modules is set. Instead, just detect if any module is updated,
and only rebuild initramfs if found any updated kernel module.
Tested with in-tree kernel modules, out-of-tree kernel modules, weak
modules, all worked as expected.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Previously only the symlink's timestamp is used for checking if file are
modified, this will not trigger a rebuild if the symlink target it
modified.
So check both symlink timestamp and symlink target timestamp, rebuild
the initramfs on both symlink changed and target changed.
Also give a proper error message if the file doesn't exist.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
When reading kdump configs, a single parsing should be enough and this
saves a lot of duplicated striping call which speed up the total load
speed.
Speed up about 2 second when building and 0.1 second for reload in my
tests.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Early kdump inherits the settings of normal kdump, so any changes that
caused normal kdump rebuilding also require rebuilding the system initramfs
to make sure that the changes take effect for early kdump.
Therefore, when the early kdump is enabled, provide a prompt message after
the rebuilding of kdump initramfs is completed.
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Previous we rebuild the initramfs when kenrel load module list changed,
but this is not very stable as some async services may load/unload
kernel modules, and cause unnecessary initramfs rebuild.
Instead, it's better to just check if the module required to dump to
the dump target is loaded or not, and rebuild if not loaded. This
avoids most false-positives, and ensure local target change is always
covered.
Currently only local fs dump target is covered, because this check
requires the dump target to be mounted when building the initramfs,
this guarantee that the module is in the loaded kernel module list,
else we may still get some false positive.
dracut-install could be leveraged to combine the modalias list with
kernel loaded module list as a more stable module list in the initramfs,
but upstream dracut change need to be done first.
Passed test on a KVM VM, changing the storage between SATA/USB/VirtIO
will trigger initramfs rebuild and didn't notice any false-positive.
Also passed test on my laptop with no false-positive.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
This reverts commit 6b479b6572.
Check initramfs rebuild by looking at if there is any change of load
kernel modules list is not very stable after all. Previously we are
counting on udev to settle before kdump is started to ensure all modules
is ready, but actually any service may cause a kernel module load, even
after udev is settled.
The previous commit is trying to workaround an issue that VM created
with disk snapshot may fail in the kdump initramfs. The better fix is to
not include the kdump initramfs in the disk snapshot at all, as the
kdump initramfs is not generated for a generic use. And With new added
"kdumpctl reload" command, admins could rebuild the image easily, and
should rebuild the initramfs on hardware change manually.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Use "kdumpctl rebuild" to rebuild the image directly. This could help
admins to rebuild kdump image directly.
Also merge fadump related initramfs backup/restore into setup_initrd,
and do permission only when actually trying to rebuild the image.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
With kernel commit 0823c68b054b ("powerpc/fadump: re-register firmware-
assisted dump if already registered") support is enabled to re-register
when FADump is alredy registered. Leverage that option in kdump scripts.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Kairui Song <kasong@redhat.com>
The idea behind adding support for dracut '--rebuild' option was to
ensure the initrd built for fadump takes into consideration all the
build parameters passed to original initrd. Pass original initrd
instead of current default initrd for rebuild as current initrd
might already have build parameters from original initrd along
with parameters from previous fadump intird build making the
build parameters look like this after a few iterations:
-H --persistent-policy 'by-uuid' -f --quiet --hostonly --hostonly-
cmdline --hostonly-i18n --hostonly-mode 'strict' -o 'plymouth dash
resume ifcfg' --mount '/dev/mapper/rhel_zzfp219--lp3-home /kdumproot
//home xfs defaults' -f --kver '4.18.0-60.el8.ppc64le' --quiet
--hostonly --hostonly-cmdline --hostonly-i18n --hostonly-mode 'strict'
-o 'plymouth dash resume ifcfg' --mount '/dev/mapper/rhel_zzfp219--lp3-home
/kdumproot//home xfs defaults' -f --kver '4.18.0-60.el8.ppc64le' --quiet
--hostonly --hostonly-cmdline --hostonly-i18n --hostonly-mode 'strict'
-o 'plymouth dash resume ifcfg' --mount '/dev/mapper/rhel_zzfp219--lp3-home
/kdumproot//home xfs defaults' -f --kver '4.18.0-60.el8.ppc64le' --include
'/tmp/fadump.initramfs' '/etc/fadump.initramfs' --include
'/tmp/fadump.initramfs' '/etc/fadump.initramfs' --include
'/tmp/fadump.initramfs' '/etc/fadump.initramfs'
--
Since it is not desirable to build initrd with stale and/or duplicate
build parameters, use original initrd (backed up) to rebuild fadump
initrd, instead of current default initrd.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
If a crash occurs repeatedly after enabling kdump, the system goes
into a crash loop and the dump target may get filled up by vmcores.
This is likely especially with early kdump.
This patch introduces 'final_action' option to kdump.conf, in order
for users to be able to power off the system even after capturing
a vmcore successfully.
Signed-off-by: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Kairui Song <kasong@redhat.com>
In preparation for adding 'final_action' option, since it's confusing
to have the 'final_action' and 'default' options at the same time,
this patch introduces 'failure_action' as an alias of the 'default'
option to /etc/kdump.conf, and makes 'default' obsolete to be removed
in the future.
Also, the "default action" term is renamed to "failure action".
Signed-off-by: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Kairui Song <kasong@redhat.com>
In commit b34ce3a reload support was added to kdumpctl but the usage
info is not updated. Now add reload to usage output to let user aware
of the new command.
Signed-off-by: Kairui Song <kasong@redhat.com>
Add reload support to kdumpctl, reload will simply unload current
loaded kexec crash kernel and initramfs, and load it again.
Changes in /etc/sysconfig/kdump will take effect with kdumpctl
reload, but reloading will not check the content of
/etc/kdump.conf and won't rebuild anything. reload is fast, the only
time-consuming part of kdumpctl reload is loading kernel and initramfs
with kexec which is always necessary.
Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Currently the kdumpctl script doesn't check if the raw device is
formatted which might destroy existing data at the time of dump
capture.
This patch addresses this issue, by ensuring kdumpctl prints
a warning in case it finds the raw device to be formatted.
Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
Currently the kdumpctl script doesn't check if the path option is
set more than once due to which a vmcore is not captured.
This patch addresses this issue by ensuring that only one path
is specified in /etc/kdump.conf file.
Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
Currently, we only rebuilt kdump initramfs on config file change,
fs change, or watchdog related change. This will not cover the case
that hardware changed but fs layout and other configurations still
stays the same, and kdump may fail.
To cover such case, we can detect and compare loaded kernel modules,
if a hardware change requires the image to be rebuilt, loaded kernel
modules must have changed.
Starting from commit 7047294 dracut will record loaded kernel modules
when the image is built if hostonly mode is enabled. With this patch,
kdumpctl will compare the recorded value with currently loaded kernel
modules, and rebuild the image on change.
"kdumpctl start" will be a bit slower, as we have to call lsinitrd one
more time to get the loaded kernel modules list. I measure the time
consumption and we have an overall 0.2s increased loading time.
Time consumption of command "kdumpctl restart":
Before:
real 0m0.587s
user 0m0.481s
sys 0m0.102s
After:
real 0m0.731s
user 0m0.591s
sys 0m0.133s
Time comsumption of command "kdumpctl restart" with image rebuild:
Before (force rebuild):
real 0m10.972s
user 0m8.966s
sys 0m1.318s
After (inserted ~100 new modules):
real 0m11.220s
user 0m9.387s
sys 0m1.337s
Signed-off-by: Kairui Song <kasong@redhat.com>
we move some common functions from kdumpctl to kdump-lib.sh, the
functions could be used in other modules, such as early kdump.
It has no bad effect.
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Reviewed-by: Kazuhito Hagio <khagio@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>
When core_collector is changed, the kdump initramfs needs to
be rebuilt before it is loaded.
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
When using "dracut_args --mount" to specify dump target, e.g. nfs like:
path /
core_collector makedumpfile -d 31
dracut_args --mount "host:/path /var/crash nfs defaults"
kdump service should neither guarantees the correctness, nor relabels it.
For current code, since dracut_args dump targets are likely not mounted
so kdump service mistakenly relabel the rootfs, which is meanless and
takes very long time.
Signed-off-by: Pingfan Liu <piliu@redhat.com>
This reverts commit 2040103bd7.
Reason is it's based on the environment of 1st kernel where all
present devices could be active and initialized during bootup.
Then all pci devices will request irqs. While kdump only brings
up those devices which are necessary for vmcore dumping. So this
commit is not meaningful and helpless to very large extent. And
it will print out 'Warning' when calculated result is larger than
1 cpu, actually it's a false positive report most of the time.
So revert the commit, and can check the git history for later
reference.
[dyoung]: on some machine this warning message shows up but
later we found the irq numbers with and without nr_cpus=1 is
quite different so this need more investigation since
the formula is not accurate.
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Resolves: BZ1484945
https://bugzilla.redhat.com/show_bug.cgi?id=1484945
Currently the kdumpctl script doesn't handle
whitespaces (including TABs) which might be there before
an option name in the kdump.conf
This patch addresses this issue, by ensuring that the
kdumpctl errors out in case it finds any stray space(s)
or tab(s) before a option name.
Reported-by: Kenneth D'souza <kdsouza@redhat.com>
Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Pratyush Anand <panand@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
As default initrd is used for booting fadump capture kernel, it must be
rebuilt with dump capture capability when dump mode is fadump. Check if
default initrd is already fadump capable and rebuild, if necessary.
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Reviewed-by: Xunlei Pang <xlpang@redhat.com>
Now with the help of "--hostonly-cmdline", dracut will generate
the needed cmdlines for the dump target, so we can avoid the
corresponding duplicate or unnecessary inheritage.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Currently, we kept "root=X" for the dump_to_rootfs case, this
patch consolidates to use "--mount" for all the kdump mounts.
One advantage of this way is that dracut can correctly mark root
(in case of dump_to_rootfs is specified) as the host device when
"--no-hostonly-default-device" is added in the following patch.
Changed the code style in passing, as shellcheck tool reported:
Use $(..) instead of deprecated `..`
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Make is_fadump_capable() a library function, as we will need
it in mkdumprd.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
This reverts commit cb38b32dfc.
We are going to add "--hostonly-cmdline" dracut argument in
the following patch.
With the help of "--hostonly-cmdline", dracut will generate
"rd.lvm.lv=X" for us, no need to implement here again.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
This reverts commit 54a5bcc4ee.
We are going to add "--no-hostonly-default-device" dracut argument
in the following patch.
With the help of "--no-hostonly-default-device", dracut only
adds the dump target as host devices, which naturally guarantees
only required dracut modules being selected.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
We met a problem on AMD machines, when using "nr_cpus=4" for
kdump, and crash happens on cpus other than cpu0, kdump kernel
will fail to boot and eventually reset.
After some debugging, we found that it stuck at the kernel path
do_boot_cpu()-> ... ->wakeup_secondary_cpu_via_init():
apic_icr_write(APIC_INT_LEVELTRIG|APIC_INT_ASSERT|APIC_DM_INIT,
phys_apicid);
that is, it stuck at sending INIT from AP to BP and reset, which
is actually what "disable_cpu_apicid=X" tries to solve. Printing
the value of @phys_apicid showed that it was the value of "apicid"
other that of "initial apicid" showed by /proc/cpuinfo.
As described in x86 specification:
"In MP systems, the local APIC ID is also used as a processor ID by the
BIOS and the operating system. Some processors permit software to modify
the APIC ID. However, the ability of software to modify the APIC ID is
processor model specific. Because of this, operating system software
should avoid writing to the local APIC ID register. The value returned by
bits 31-24 of the EBX register (when the CPUID instruction is executed with a
source operand value of 1 in the EAX register) is always the Initial APIC ID
(determined by the platform initialization). This is true even if software
has changed the value in the Local APIC ID register."
From kernel commit 151e0c7de("x86, apic, kexec: Add disable_cpu_apicid
kernel parameter"), we can see in generic_processor_info(), it uses
a)read_apic_id() and b)@apicid to compare with @disabled_cpu_apicid.
a)@apicid which is actually @phys_apicid above-mentioned is from the
following calltrace(on the problematic AMD machine):
generic_processor_info+0x37/0x300
acpi_register_lapic+0x30/0x90
acpi_parse_lapic+0x40/0x50
acpi_table_parse_entries_array+0x171/0x1de
acpi_boot_init+0xed/0x50f
The value of @apicid(from acpi MADT) is equal to the value of "apicid"
showed by /proc/cpuinfo as proved by our debug printk.
b)read_apic_id() gets the value from LAPIC ID register which is "apicid"
as well.
While the value of "initial apicid" is from cpuid instruction.
One example of "apicid" and "initial apicid" of cpu0 from /proc/cpuinfo
on AMD machine:
apicid : 32
initial apicid : 0
Therefore, we should assign /proc/cpuifo "apicid" to "disable_cpu_apicid=X".
We've never met such issue before, because we usually tested "nr_cpus=1",
and mostly on Intel machines, and "apicid" and "initial apicid" have the
same value in most cases on Intel machines.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Resolves: bz1451717
https://bugzilla.redhat.com/1451717
When there is no crypt related kdump target, we can safely
omit "crypt" dracut module, this can avoid the pop asking
disk password during kdump boot in some cases.
This patch introduces omit_dracut_modules() before calling
dracut, we can omit more modules to reduce initrd size in
the future.
We don't want to omit any module for fadump, thus we move
is_fadump_capable() into kdump-lib.sh as a helper to use.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
