diff options
Diffstat (limited to 'kernel/kexec_core.c')
-rw-r--r-- | kernel/kexec_core.c | 37 |
1 files changed, 31 insertions, 6 deletions
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index 11b64a63c0f8..8dc659144869 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -310,12 +310,9 @@ static void kimage_free_pages(struct page *page) void kimage_free_page_list(struct list_head *list) { - struct list_head *pos, *next; + struct page *page, *next; - list_for_each_safe(pos, next, list) { - struct page *page; - - page = list_entry(pos, struct page, lru); + list_for_each_entry_safe(page, next, list, lru) { list_del(&page->lru); kimage_free_pages(page); } @@ -853,7 +850,12 @@ struct kimage *kexec_image; struct kimage *kexec_crash_image; int kexec_load_disabled; -void crash_kexec(struct pt_regs *regs) +/* + * No panic_cpu check version of crash_kexec(). This function is called + * only when panic_cpu holds the current CPU number; this is the only CPU + * which processes crash_kexec routines. + */ +void __crash_kexec(struct pt_regs *regs) { /* Take the kexec_mutex here to prevent sys_kexec_load * running on one cpu from replacing the crash kernel @@ -876,6 +878,29 @@ void crash_kexec(struct pt_regs *regs) } } +void crash_kexec(struct pt_regs *regs) +{ + int old_cpu, this_cpu; + + /* + * Only one CPU is allowed to execute the crash_kexec() code as with + * panic(). Otherwise parallel calls of panic() and crash_kexec() + * may stop each other. To exclude them, we use panic_cpu here too. + */ + this_cpu = raw_smp_processor_id(); + old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu); + if (old_cpu == PANIC_CPU_INVALID) { + /* This is the 1st CPU which comes here, so go ahead. */ + __crash_kexec(regs); + + /* + * Reset panic_cpu to allow another panic()/crash_kexec() + * call. + */ + atomic_set(&panic_cpu, PANIC_CPU_INVALID); + } +} + size_t crash_get_memory_size(void) { size_t size = 0; |