kpatch_ctl: page allocation failure: order:6, mode:0x40cc0(GFP_KERNEL|__GFP_COMP), nodemask=(null),cpuset=/,mems_allowed=0

Issue

• KernelCare update fails with the error on AWS kernel:

  kpatch_ctl: page allocation failure: order:6, mode:0x40cc0(GFP_KERNEL|__GFP_COMP), nodemask=(null),cpuset=/,mems_allowed=0

• The following can be seen in dmesg

  [57924504.394302] CPU: 0 PID: 2408676 Comm: kpatch_ctl Tainted: G           OE     5.4.0-1032-aws #33~18.04.1-Ubuntu
  [57924504.394303] Hardware name: Xen HVM domU, BIOS 4.2.amazon 08/24/2006
  [57924504.394304] Call Trace:
  [57924504.394312]  dump_stack+0x6d/0x95
  [57924504.394316]  warn_alloc+0xfe/0x160
  [57924504.394318]  __alloc_pages_slowpath+0xe19/0xe50
  [57924504.394321]  ? __switch_to_asm+0x34/0x70
  [57924504.394323]  ? __switch_to_asm+0x40/0x70
  [57924504.394324]  ? __schedule+0x29b/0x720
  [57924504.394326]  __alloc_pages_nodemask+0x2cd/0x320
  [57924504.394329]  alloc_pages_current+0x6a/0xe0
  [57924504.394331]  kmalloc_order+0x1e/0x80
  [57924504.394332]  kmalloc_order_trace+0x24/0xb0
  [57924504.394337]  ? vprintk_func+0x47/0xc0
  [57924504.394341]  ? _cond_resched+0x19/0x40
  [57924504.394342]  ? mutex_lock+0x12/0x40
  [57924504.394346]  ? kcare_ioctl+0x6dc/0x850 [kcare]
  [57924504.394349]  ? do_vfs_ioctl+0xa9/0x640
  [57924504.394353]  ? __audit_syscall_entry+0xdd/0x130
  [57924504.394354]  ? ksys_ioctl+0x75/0x80
  [57924504.394356]  ? __x64_sys_ioctl+0x1a/0x20
  [57924504.394359]  ? do_syscall_64+0x57/0x190
  [57924504.394361]  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [57924504.394363] Mem-Info:
  [57924504.394366] active_anon:2241862 inactive_anon:723542 isolated_anon:14
                     active_file:428479 inactive_file:260656 isolated_file:31
                     unevictable:0 dirty:1186 writeback:0 unstable:0
                     slab_reclaimable:131951 slab_unreclaimable:28217
                     mapped:54697 shmem:24117 pagetables:10538 bounce:0
                     free:54756 free_pcp:0 free_cma:0

Environment

• AWS
• KernelCare

Solution

The problem has been fixed in this task - KCARE-12403 which was released on 20 April 2023 

Please make sure that you are using the latest version of the KernelCare tool and that the latest patches have been applied.