diff options
Diffstat (limited to 'kernel/crash_core.c')
| -rw-r--r-- | kernel/crash_core.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/kernel/crash_core.c b/kernel/crash_core.c index 40388ad51034..34dc7bddfd77 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -740,6 +740,33 @@ subsys_initcall(crash_notes_memory_init); #ifdef CONFIG_CRASH_HOTPLUG #undef pr_fmt #define pr_fmt(fmt) "crash hp: " fmt + +/* + * This routine utilized when the crash_hotplug sysfs node is read. + * It reflects the kernel's ability/permission to update the crash + * elfcorehdr directly. + */ +int crash_check_update_elfcorehdr(void) +{ + int rc = 0; + + /* Obtain lock while reading crash information */ + if (!kexec_trylock()) { + pr_info("kexec_trylock() failed, elfcorehdr may be inaccurate\n"); + return 0; + } + if (kexec_crash_image) { + if (kexec_crash_image->file_mode) + rc = 1; + else + rc = kexec_crash_image->update_elfcorehdr; + } + /* Release lock now that update complete */ + kexec_unlock(); + + return rc; +} + /* * To accurately reflect hot un/plug changes of cpu and memory resources * (including onling and offlining of those resources), the elfcorehdr @@ -770,6 +797,10 @@ static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu) image = kexec_crash_image; + /* Check that updating elfcorehdr is permitted */ + if (!(image->file_mode || image->update_elfcorehdr)) + goto out; + 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); |