lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 23 Oct 2020 02:53:20 +0800 From: Chen Yu <yu.c.chen@...el.com> To: Andy Shevchenko <andy.shevchenko@...il.com> Cc: "Rafael J. Wysocki" <rjw@...ysocki.net>, Len Brown <len.brown@...el.com>, Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Andy Shevchenko <andriy.shevchenko@...ux.intel.com>, Linux PM <linux-pm@...r.kernel.org>, Linux Kernel Mailing List <linux-kernel@...r.kernel.org> Subject: Re: [PATCH][v2] PM / sysfs: Expose suspend resume driver flags in sysfs Hi Andy, On Thu, Oct 22, 2020 at 04:36:25PM +0300, Andy Shevchenko wrote: > On Thu, Oct 22, 2020 at 12:24 PM Chen Yu <yu.c.chen@...el.com> wrote: > > > > Currently there are 4 driver flags to control system suspend/resume > > behavior: DPM_FLAG_NO_DIRECT_COMPLETE, DPM_FLAG_SMART_PREPARE, > > DPM_FLAG_SMART_SUSPEND and DPM_FLAG_MAY_SKIP_RESUME. Make these flags > > visible in sysfs as read-only to get a brief understanding of the > > expected behavior of each device during suspend/resume, so as to > > facilitate suspend/resume debugging/tuning. > > > > For example: > > /sys/devices/pci0000:00/0000:00:15.1/power/driver_flags:4 > > (DPM_FLAG_SMART_SUSPEND) > > > > /sys/devices/pci0000:00/0000:00:07.3/power/driver_flags:5 > > (DPM_FLAG_NO_DIRECT_COMPLETE | DPM_FLAG_SMART_SUSPEND) > > ... > > > +What: /sys/devices/.../power/driver_flags > > +Date: October 2020 > > +Contact: Chen Yu <yu.c.chen@...el.com> > > +Description: > > + The /sys/devices/.../driver_flags attribute contains the driver > > + flags to control system suspend/resume. The flag is a combination > > + of DPM_FLAG_NO_DIRECT_COMPLETE, DPM_FLAG_SMART_PREPARE, > > + DPM_FLAG_SMART_SUSPEND and DPM_FLAG_MAY_SKIP_RESUME, or 0 if the > > + driver has not set any flag. > > > This attribute is read-only. If > > + CONFIG_PM_ADVANCED_DEBUG is not set this attribute is empty. > > Which makes me wonder why we even expose this if the above is not set. > > ... > It will not be exposed if the config is disabled. 'empty' means 'not present' I think. > > +static struct attribute *pm_driver_flags_attrs[] = { > > +#ifdef CONFIG_PM_ADVANCED_DEBUG > > +#ifdef CONFIG_PM_SLEEP > > + &dev_attr_driver_flags.attr, > > +#endif > > +#endif > > > + NULL, > > No comma here, please. I think I commented on this internally. > Sorry I misunderstood your point previously, I can change in next version. But might need to wait for Greg to decide if this item should be exposed or not first. Thanks, Chenyu > > +}; > > -- > With Best Regards, > Andy Shevchenko
Powered by blists - more mailing lists