Looks like more of an EFI issue where it called efi_mem_reserve_persistent(). > Sent: Thursday, November 08, 2018 at 11:23 AM > From: "Qian Cai" <cai@xxxxxx> > To: linux-kernel@xxxxxxxxxxxxxxx > Cc: linux-mm@xxxxxxxxx > Subject: BUG: sleeping function called from invalid context at mm/slab.h:421 > > Just booting up the latest git master (b00d209) on an aarch64 server and saw this. > > Nov 8 11:06:36 huawei-t2280-03 kernel: BUG: sleeping function called from invalid context at mm/slab.h:421 > Nov 8 11:06:36 huawei-t2280-03 kernel: in_atomic(): 1, irqs_disabled(): 128, pid: 0, name: swapper/1 > Nov 8 11:06:36 huawei-t2280-03 kernel: no locks held by swapper/1/0. > Nov 8 11:06:36 huawei-t2280-03 kernel: irq event stamp: 0 > Nov 8 11:06:36 huawei-t2280-03 kernel: hardirqs last enabled at (0): [<0000000000000000>] (null) > Nov 8 11:06:36 huawei-t2280-03 kernel: hardirqs last disabled at (0): [<ffff2000080e24ec>] copy_process.isra.32.part.33+0x460/0x1534 > Nov 8 11:06:36 huawei-t2280-03 kernel: softirqs last enabled at (0): [<ffff2000080e24ec>] copy_process.isra.32.part.33+0x460/0x1534 > Nov 8 11:06:36 huawei-t2280-03 kernel: softirqs last disabled at (0): [<0000000000000000>] (null) > Nov 8 11:06:36 huawei-t2280-03 kernel: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.20.0-rc1+ #3 > Nov 8 11:06:36 huawei-t2280-03 kernel: Call trace: > Nov 8 11:06:36 huawei-t2280-03 kernel: dump_backtrace+0x0/0x190 > Nov 8 11:06:36 huawei-t2280-03 kernel: show_stack+0x24/0x2c > Nov 8 11:06:36 huawei-t2280-03 kernel: dump_stack+0xa4/0xe0 > Nov 8 11:06:36 huawei-t2280-03 kernel: ___might_sleep+0x208/0x234 > Nov 8 11:06:36 huawei-t2280-03 kernel: __might_sleep+0x58/0x8c > Nov 8 11:06:36 huawei-t2280-03 kernel: kmem_cache_alloc_trace+0x29c/0x420 > Nov 8 11:06:36 huawei-t2280-03 kernel: efi_mem_reserve_persistent+0x50/0xe8 > Nov 8 11:06:36 huawei-t2280-03 kernel: its_cpu_init_lpis+0x298/0x2e0 > Nov 8 11:06:36 huawei-t2280-03 kernel: its_cpu_init+0x7c/0x1a8 > Nov 8 11:06:36 huawei-t2280-03 kernel: gic_starting_cpu+0x28/0x34 > Nov 8 11:06:36 huawei-t2280-03 kernel: cpuhp_invoke_callback+0x104/0xd04 > Nov 8 11:06:36 huawei-t2280-03 kernel: notify_cpu_starting+0x60/0xa0 > Nov 8 11:06:36 huawei-t2280-03 kernel: secondary_start_kernel+0xcc/0x178 > > Any idea?