On 03/06/23 at 11:22am, Eric DeVolder wrote: ...... > +static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu) > +{ > + /* Obtain lock while changing crash information */ > + if (kexec_trylock()) { > + > + /* Check kdump is loaded */ > + if (kexec_crash_image) { > + struct kimage *image = kexec_crash_image; > + > + if (hp_action == KEXEC_CRASH_HP_ADD_CPU || > + hp_action == KEXEC_CRASH_HP_REMOVE_CPU) > + pr_debug("hp_action %u, cpu %u\n", hp_action, cpu); > + else > + pr_debug("hp_action %u\n", hp_action); > + > + /* > + * When the struct kimage is allocated, the elfcorehdr_index > + * is set to -1. Find the segment containing the elfcorehdr, > + * if not already found. This works for both the kexec_load > + * and kexec_file_load paths. > + */ > + if (image->elfcorehdr_index < 0) { > + unsigned long mem; > + unsigned char *ptr; > + unsigned int n; > + > + for (n = 0; n < image->nr_segments; n++) { > + mem = image->segment[n].mem; > + ptr = kmap_local_page(pfn_to_page(mem >> PAGE_SHIFT)); > + if (ptr) { > + /* The segment containing elfcorehdr */ > + if (memcmp(ptr, ELFMAG, SELFMAG) == 0) { > + image->elfcorehdr_index = (int)n; > + } > + kunmap_local(ptr); > + } > + } > + } > + > + if (image->elfcorehdr_index < 0) { > + pr_err("unable to locate elfcorehdr segment"); > + goto out; > + } > + > + /* Needed in order for the segments to be updated */ > + arch_kexec_unprotect_crashkres(); > + > + /* Differentiate between normal load and hotplug update */ > + image->hp_action = hp_action; > + > + /* Now invoke arch-specific update handler */ > + arch_crash_handle_hotplug_event(image); > + > + /* No longer handling a hotplug event */ > + image->hp_action = KEXEC_CRASH_HP_NONE; > + image->elfcorehdr_updated = true; It's good to initialize the image->hp_action here, however where do you check it? Do you plan to add some check somewhere? > + > + /* Change back to read-only */ > + arch_kexec_protect_crashkres(); > + } > + > +out: > + /* Release lock now that update complete */ > + kexec_unlock(); > + } > +} ...... _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec