Bug 202511 - amdgpu fails to load saying "Could not allocate 8192 bytes percpu data"

[Bjorn Helgaas]

https://bugzilla.kernel.org/show_bug.cgi?id=202511

>From reporter (Michael):

> Working on 4.17.19 (which is what I use) but any kernel 4.19* 4.20* I try has this issue. Built amdgpu as a module, when it tries to load it (or I try to modprobe it) I get
> 
>   amdgpu: Could not allocate 8192 bytes percpu data
>   ath10k_pci 0000:02:00.0: board_file api 2 bmi_id N/A crc32 8aedfa4a
>   percpu: allocation failed, size=8192 align=4096 atomic=0, alloc from reserved chunk failed
>   CPU: 1 PID: 2620 Comm: systemd-udevd Not tainted 4.20.6-gentoo #1
>   Hardware name: Acer Aspire A315-41/Metapod_RR, BIOS V1.11 10/30/2018
>   Call Trace:
>    dump_stack+0x46/0x5b
>    pcpu_alloc+0x56e/0x590
>    ? find_module_all+0x4c/0x80
>    load_module+0xb51/0x1e80
>    ? wait_woken+0x80/0x80
>    __se_sys_finit_module+0xe0/0xf0
>    do_syscall_64+0x4a/0x100
>    entry_SYSCALL_64_after_hwframe+0x44/0xa9
>   RIP: 0033:0x7fb64cd77fb9
>   Code: 00 00 00 75 05 48 83 c4 18 c3 e8 42 a5 01 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 9f 4e 2c 00 f7 d8 64 89 01 48
>   RSP: 002b:00007ffe5fe76eb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
>   RAX: ffffffffffffffda RBX: 00005615a81b2c10 RCX: 00007fb64cd77fb9
>   RDX: 0000000000000000 RSI: 00007fb64dd3c1c5 RDI: 000000000000000f
>   RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
>   R10: 000000000000000f R11: 0000000000000246 R12: 00005615a81d0290
>   R13: 00007fb64dd3c1c5 R14: 0000000000020000 R15: 0000000003938700

Full dmesg and bisection info in the bugzilla.  Any help is welcome.