[linux-pm] [patch/rft 2.6.17-rc2] swsusp resume must not device_suspend()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, 27 Apr 2006, Pavel Machek wrote:

> Hi!
> 
> > The right way to solve this is to make sure that the resuming kernel can
> > correctly determine whether the power session (way back from the original
> > sw-suspend) is still intact.  It's expected that in many cases it won't
> > be, because most systems won't provide suspend current while the machine
> > is off.  We have to guarantee that the boot kernel's actions won't end up
> > fooling the resuming kernel into thinking that the power sessions are
> > intact when in fact they aren't.  (Furthermore, in an ideal world, we
> > would also make sure that the boot kernel won't destroy any power sessions
> > that still _are_ intact.  Right now we have no way to do this, because the
> > drivers in the boot kernel don't know that it _is_ a boot kernel.)
> 
> You don't know if it is boot or resume until you read the disk, sorry.

According to David this shouldn't matter.  During swsusp the system is
supposed to be completely off, with no suspend power available.  Hence all
the power sessions are guaranteed to be interrupted, and the boot kernel
doesn't have to worry about destroying any of them.

Alan Stern


[Index of Archives]     [Linux ACPI]     [Netdev]     [Ethernet Bridging]     [Linux Wireless]     [CPU Freq]     [Kernel Newbies]     [Fedora Kernel]     [Security]     [Linux for Hams]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux Admin]     [Samba]

  Powered by Linux