On 11/29/2017 09:09 AM, Ingo Molnar wrote:
> 
> * Jarkko Nikula <jarkko.nikula@linux.intel.com> wrote:
> 
>> Hi
>> 
>> Suspend-to-ram and resume stopped working on v4.15-rc1 and I 
>> bisected it to commit ca37e57bbe0c ("x86/entry/64: Add missing 
>> irqflags tracing to native_load_gs_index()").
>> 
>> I noticed it on Intel Kabylake (core) and Apollolake (atom) based 
>> prototype machines. Symptoms are that machine appears to enter
>> into suspend but resumes instantly and hangs. Unfortunately no
>> logs.
>> 
>> If I revert ca37e57bbe0c on v4.15-rc1 it works as expected.
> 
> Hm, that commit looks broken with irq-tracing enabled. Does the
> patch below fix it?
> 
No, it makes the machine not to boot at all :-(

Log below when I used my config (now attached). With x86_64_defconfig it 
booted twice but didn't survive suspend/resume. However several other 
boot attempts with x86_64_defconfig failed somewhat similarly. Not in 
the same place but hanging anyway. With my own config it seems to always 
end up failing in trace_hardirqs_off_caller.

Then I noticed suspend/resume is not working on v4.14 either when I use 
the x86_64_defconfig. Maybe unrelated issue.

...
[    1.917851] clocksource: tsc: mask: 0xffffffffffffffff max_cycles:
0x19f2297dd97, max_idle_ns: 440795236593 ns
[    1.929795] workingset: timestamp_bits=62 max_order=21 bucket_order=0
[    1.939699] BUG: stack guard page was hit at ffffc90000233ff8 (stack
is ffffc90000234000..ffffc90000237fff)
** 606 printk messages dropped **
[    1.940339]  ? native_iret+0x7/0x7
[    1.940340]  ? error_entry+0x6f/0xc0
[    1.940341]  error_entry+0x6f/0xc0
[    1.940342] RIP: 0010:trace_hardirqs_off_caller+0x8/0xc0
[    1.940342] RSP: 0000:ffffc90000257048 EFLAGS: 00010093 ORIG_RAX:
0000000000000000
[    1.940343] RAX: 000000008168ad47 RBX: 0000000000000001 RCX:
ffffffff8168ad47
[    1.940343] RDX: ffff8802b505bb28 RSI: 0000000000000000 RDI:
ffffffff8168b5ef
[    1.940344] RBP: ffffc900002570a0 R08: 00000000ebddc52a R09:
0000000000000001
[    1.940344] R10: 0000000000000000 R11: 0000000000000000 R12:
ffff8802b505a840
[    1.940345] R13: ffff8802b505b048 R14: ffff8802b39dc800 R15:
ffff8802b505a840
[    1.940346]  ? page_fault+0xc/0x30
[    1.940347]  ? native_iret+0x7/0x7
[    1.940348]  ? error_entry+0x6f/0xc0
[    1.940349]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[    1.940350]  ? native_iret+0x7/0x7
[    1.940351]  ? error_entry+0x6f/0xc0
[    1.940352]  error_entry+0x6f/0xc0
[    1.940353] RIP: 0010:trace_hardirqs_off_caller+0x8/0xc0
[    1.940353] RSP: 0000:ffffc90000257168 EFLAGS: 00010093 ORIG_RAX:
0000000000000000
[    1.940354] RAX: 000000008168ad47 RBX: 0000000000000001 RCX:
ffffffff8168ad47
[    1.940354] RDX: ffff8802b505bb28 RSI: 0000000000000000 RDI:
ffffffff8168b5ef
[    1.940355] RBP: ffffc900002571c0 R08: 00000000ebddc52a R09:
0000000000000001
[    1.940355] R10: 0000000000000000 R11: 0000000000000000 R12:
ffff8802b505a840
[    1.940356] R13: ffff8802b505b048 R14: ffff8802b39dc800 R15:
ffff8802b505a840
[    1.940357]  ? page_fault+0xc/0x30
[    1.940358]  ? native_iret+0x7/0x7
[    1.940359]  ? error_entry+0x6f/0xc0
[    1.940360]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[    1.940361]  ? native_iret+0x7/0x7
[    1.940362]  ? error_entry+0x6f/0xc0
[    1.940363]  error_entry+0x6f/0xc0

and this continues.

-- 
Jarkko