Re: Suspend/resume with FTRACE enabled doesn’t work anymore

[Paul Menzel <pmenzel+linux-ftrace@molgen.mpg.de>]

[-- Attachment #1: Type: text/plain, Size: 1337 bytes --]

Dear Linux folks,


On 01/17/18 15:20, Paul Menzel wrote:

> Testing Linux 4.15-rc8 on a Lenovo T60 (32 bit) and Dell XPS 13 9360 (64 
> bit) suspend to and resume from ACPI S3 doesn’t work anymore. 
> `./sleepgraph.py -config config/suspend-callgraph.cfg` [1] is used to 
> enable the FTRACE framework.
> 
> On the Lenovo T60 the system seems to enter ACPI S3 state just fine, but 
> doesn’t wake up.
> 
> On the Dell XPS 13 9360 the system doesn’t enter ACPI S3 and just 
> freezes with the display still on, and the messages below.
> 
> ```
> […]
> INITIALIZING FTRACE...
> Setting trace buffers to 3145728 kB (786432 kB per cpu)
> ```
> 
> Please find the configuration file used for the Lenovo T60 attached.

I first thought it might be related to the UBSAN enabled, but it’s not it.

Here the results for the Dell XPS 13 9360.

Trying Linux 4.13.0-26-generic shipped with Ubuntu 16.04 everything 
works as expected with `sleepgraph`. The system suspends and resumes. 
(Though it wakes up before the power button LED turns off.)

Using their mainline Linux kernel 4.15-rc8 build from [1], Linux 
4.15-rc8 also freezes during suspend as originally reported.


Kind regards,

Paul


> [1] https://01.org/suspendresume
[2] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15-rc8/


[-- Attachment #2: S/MIME Cryptographic Signature --]
[-- Type: application/pkcs7-signature, Size: 5174 bytes --]