[PATCH v11 1/7] crash: move crash_prepare_elf64_headers

At the outcome of this patch set, the crash_prepare_elf64_headers() is utilized on both the kexec_file_load and kexec_load paths. As such, need to move this function out of kexec_file.c and into a common location crash_core.c. No functionality change. Signed-off-by: Eric DeVolder ---

[PATCH v11 4/7] kexec: exclude elfcorehdr from the segment digest

When a crash kernel is loaded via the kexec_file_load syscall, the kernel places the various segments (ie crash kernel, crash initrd, boot_params, elfcorehdr, purgatory, etc) in memory. For those architectures that utilize purgatory, a hash digest of the segments is calculated for integrity

[PATCH v11 5/7] kexec: exclude hot remove cpu from elfcorehdr notes

Due to use of CPUHP_AP_ONLINE_DYN, upon CPU unplug, the CPU is still in the for_each_present_cpu() list when within the handle_hotplug_event(). Thus the CPU must be explicitly excluded when building the new list of CPUs. This change identifies in handle_hotplug_event() the CPU to be excluded, and

[PATCH v11 6/7] crash: memory and cpu hotplug sysfs attributes

This introduces the crash_hotplug attribute for memory and CPUs for use by userspace. This change directly facilitates the udev rule for managing userspace re-loading of the crash kernel upon hot un/plug changes. For memory, this changeset introduces the crash_hotplug attribute to the

[PATCH v11 3/7] crash: add generic infrastructure for crash hotplug support

CPU and memory change notifications are received in order to regenerate the elfcorehdr. To support cpu hotplug, a callback is registered to capture the CPUHP_AP_ONLINE_DYN online and offline events via cpuhp_setup_state_nocalls(). To support memory hotplug, a notifier is registered to capture

[PATCH v11 0/7] crash: Kernel handling of CPU and memory hot un/plug

When the kdump service is loaded, if a CPU or memory is hot un/plugged, the crash elfcorehdr, which describes the CPUs and memory in the system, must also be updated, else the resulting vmcore is inaccurate (eg. missing either CPU context or memory regions). The current solution utilizes udev to

[PATCH v11 2/7] crash: prototype change for crash_prepare_elf64_headers

>From within crash_prepare_elf64_headers() there is a need to reference the struct kimage hotplug members. As such, this change passes the struct kimage as a parameter to the crash_prepare_elf64_headers(). The hotplug members are added in "crash: add generic infrastructure for crash hotplug

[PATCH v11 7/7] x86/crash: Add x86 crash hotplug support

For x86_64, when CPU or memory is hot un/plugged, the crash elfcorehdr, which describes the CPUs and memory in the system, must also be updated. When loading the crash kernel via kexec_load or kexec_file_load, the elfcorehdr is identified at run time in crash_core:handle_hotplug_event(). To

Re: [PATCH RFC 1/2] coding-style.rst: document BUG() and WARN() rules ("do not crash the kernel")

On 26.08.22 03:43, Dave Young wrote: > Hi David, > > [Added more people in cc] > Hi Dave, thanks for your input! [...] >> Side note: especially with kdump() I feel like we might see much more >> widespread use of panic_on_warn to be able to actually extract debug >> information in a

Re: linux-next: Tree for Aug 25 (kunit: virt/nitro_enclaves; also kexec)

On 8/24/22 22:44, Stephen Rothwell wrote: > Hi all, > > Changes since 20220824: > on x86_64: ld: vmlinux.o: in function `kunit_kcalloc': include/kunit/test.h:369: undefined reference to `kunit_kmalloc_array' ld: vmlinux.o: in function `ne_misc_dev_test_merge_phys_contig_memory_regions':