/* If I don't overlap any segments I have found my hole! */
if (i == image->nr_segments) {
pages = pfn_to_page(hole_start >> PAGE_SHIFT);
+ image->control_page = hole_end;
break;
}
}
- if (pages)
- image->control_page = hole_end;
return pages;
}
static int __init crash_notes_memory_init(void)
{
/* Allocate memory for saving cpu registers. */
- crash_notes = alloc_percpu(note_buf_t);
+ size_t size, align;
+
+ /*
+ * crash_notes could be allocated across 2 vmalloc pages when percpu
+ * is vmalloc based . vmalloc doesn't guarantee 2 continuous vmalloc
+ * pages are also on 2 continuous physical pages. In this case the
+ * 2nd part of crash_notes in 2nd page could be lost since only the
+ * starting address and size of crash_notes are exported through sysfs.
+ * Here round up the size of crash_notes to the nearest power of two
+ * and pass it to __alloc_percpu as align value. This can make sure
+ * crash_notes is allocated inside one physical page.
+ */
+ size = sizeof(note_buf_t);
+ align = min(roundup_pow_of_two(sizeof(note_buf_t)), PAGE_SIZE);
+
+ /*
+ * Break compile if size is bigger than PAGE_SIZE since crash_notes
+ * definitely will be in 2 pages with that.
+ */
+ BUILD_BUG_ON(size > PAGE_SIZE);
+
+ crash_notes = __alloc_percpu(size, align);
if (!crash_notes) {
pr_warn("Kexec: Memory allocation for saving cpu register states failed\n");
return -ENOMEM;
#endif
VMCOREINFO_NUMBER(PG_head_mask);
VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
+#ifdef CONFIG_X86
+ VMCOREINFO_NUMBER(KERNEL_IMAGE_SIZE);
+#endif
#ifdef CONFIG_HUGETLBFS
VMCOREINFO_SYMBOL(free_huge_page);
#endif