On Thu, Jul 14, 2016 at 04:29:42PM +0800, Feng Tang wrote: > if you only want it to work, you can try an old patch > https://bugzilla.kernel.org/attachment.cgi?id=76071 from a similar bug > https://bugzilla.kernel.org/show_bug.cgi?id=41932 > > Alistair Buxton confirmed it work for 3.18 at least > https://bugzilla.kernel.org/show_bug.cgi?id=107151#c16 That patch is a bit too ripe by now. Would need a fresh squeezed one. > > Thanks, > Feng > > On Wed, Jul 13, 2016 at 10:54 PM, Ville Syrjälä > <ville.syrjala@xxxxxxxxxxxxxxx> wrote: > > On Tue, May 31, 2016 at 10:26:50AM +0300, Ville Syrjälä wrote: > >> On Mon, May 30, 2016 at 10:43:51PM +0200, Rafael J. Wysocki wrote: > >> > On Thu, May 26, 2016 at 8:32 PM, Ville Syrjälä > >> > <ville.syrjala@xxxxxxxxxxxxxxx> wrote: > >> > > On Wed, May 18, 2016 at 10:24:24AM +0300, Ville Syrjälä wrote: > >> > >> On Wed, May 18, 2016 at 01:14:42AM +0200, Rafael J. Wysocki wrote: > >> > >> > On 5/16/2016 9:39 PM, Ville Syrjälä wrote: > >> > >> > > On Wed, May 11, 2016 at 04:34:06PM +0300, Ville Syrjälä wrote: > >> > >> > >> On Wed, May 11, 2016 at 08:44:45AM -0400, Steven Rostedt wrote: > >> > >> > >>> On Wed, 11 May 2016 15:21:16 +0300 > >> > >> > >>> Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> wrote: > >> > >> > >>> > >> > >> > >>>> Yeah can't get anything from the machine at that point. netconsole > >> > >> > >>>> didn't help either, and no serial on this machine. And IIRC I've > >> > >> > >>>> tried ramoops on this thing in the past but unfortunately the memory > >> > >> > >>>> got cleared on reboot. > >> > >> > >>>> > >> > >> > >>> Can you look at the documentation in the kernel code at > >> > >> > >>> > >> > >> > >>> Documentation/power/basic-pm-debugging.txt And follow the procedures > >> > >> > >>> for testing suspend to RAM (although it requires mostly running the > >> > >> > >>> same tests as for hibernation suspending). > >> > >> > >>> > >> > >> > >>> You can also use the tool s2ram for this as well. > >> > >> > >>> > >> > >> > >>> See Documentation/power/s2ram.txt > >> > >> > >>> > >> > >> > >>> Perhaps this can give us a bit more light onto the problem. > >> > >> > >>> > >> > >> > >>> Basically the above does partial suspend and resume, and can pinpoint > >> > >> > >>> problem areas down to a more select location. > >> > >> > >> All the pm_test modes work fine. The only difference between them was > >> > >> > >> that 'platform' required me to manually wake up the machine (hitting a > >> > >> > >> key was sufficient), whereas the others woke up without help. > >> > >> > >> > >> > >> > >> pm_trace gave me > >> > >> > >> [ 1.306633] Magic number: 0:185:178 > >> > >> > >> [ 1.322880] hash matches ../drivers/base/power/main.c:1070 > >> > >> > >> [ 1.339270] acpi device:0e: hash matches > >> > >> > >> [ 1.355414] platform: hash matches > >> > >> > >> > >> > >> > >> which is the TRACE_SUSPEND in __device_suspend_noirq(), so no help > >> > >> > >> there. > >> > >> > >> > >> > >> > >> I guess I could try to sprinkle more TRACE_RESUMEs around into some > >> > >> > >> early resume code. If anyone has good ideas where to put them it > >> > >> > >> might speed things up a bit. > >> > >> > > So I did a bunch of that and found that it gets stuck somewhere > >> > >> > > around executing the _WAK method: > >> > >> > > platform_resume_noirq > >> > >> > > acpi_pm_finish > >> > >> > > acpi_leave_sleep_state > >> > >> > > acpi_hw_sleep_dispatch > >> > >> > > acpi_hw_legacy_wake > >> > >> > > acpi_hw_execute_sleep_method > >> > >> > > acpi_evaluate_object > >> > >> > > acpi_ns_evaluate > >> > >> > > acpi_ps_execute_method > >> > >> > > acpi_ps_parse_aml > >> > >> > > > >> > >> > > It also seesm that adding a few TRACE_RESUME()s or an msleep() right > >> > >> > > after enable_nonboot_cpus() can avoid the hang, sometimes. > >> > >> > > > >> > >> > > I've attached the DSDT in case anyone is interested in looking at it. > >> > >> > > > >> > >> > > >> > >> > What if you comment out the execution of _WAK (line 318 of > >> > >> > drivers/acpi/acpica/hwsleep.c in 4.6)? Does that make any difference? > >> > >> > >> > >> Indeed it does. Tried with acpi_idle and intel_idle, and both appear to > >> > >> resume just fine with that hack. > >> > >> > >> > >> - acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state); > >> > >> + //acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state); > >> > >> + printk(KERN_CRIT "skipping _WAK\n"); > >> > > > >> > > Continuing with my detective work a bit, I decided to hack the DSDT a > >> > > bit to see if I can narrow the it down further, and looks like I found > >> > > it on the first guess. The following change stops it from hanging. > >> > > > >> > > @ -5056,7 +5056,7 @@ > >> > > If (LEqual (Arg0, 0x03)) > >> > > { > >> > > Store (0x01, \SPNF) > >> > > - TRAP (0x46) > >> > > + //TRAP (0x46) > >> > > P8XH (0x00, 0x03) > >> > > } > >> > > > >> > > So what does that do? Let's see: > >> > > > >> > > OperationRegion (IO_T, SystemIO, 0x0800, 0x10) > >> > > Field (IO_T, ByteAcc, NoLock, Preserve) > >> > > { > >> > > Offset (0x08), > >> > > TRP0, 8 > >> > > } > >> > > > >> > > OperationRegion (GNVS, SystemMemory, 0x3F5E0C7C, 0x0200) > >> > > Field (GNVS, AnyAcc, Lock, Preserve) > >> > > { > >> > > OSYS, 16, > >> > > SMIF, 8, > >> > > ... > >> > > > >> > > Method (TRAP, 1, Serialized) > >> > > { > >> > > Store (Arg0, SMIF) /* \SMIF */ > >> > > Store (0x00, TRP0) /* \TRP0 */ > >> > > Return (SMIF) /* \SMIF */ > >> > > } > >> > > > >> > > and a dump of the IOTR registers shows: > >> > > > >> > > 0x1e80: 0x0000fe01 > >> > > 0x1e84: 0x00020001 > >> > > 0x1e98: 0x000c0801 > >> > > 0x1e9c: 0x000200f0 > >> > > > >> > > which seems to be telling me that ports 0x800-0x80f and > >> > > 0xfe00-0xfe03 would trigger an SMI. > >> > > >> > Well, the name of the method kind of suggests that it triggers an SMM trap. :-) > >> > >> Which is why I wanted confirm that by looking at the IOTR regs ;) > >> > >> > > >> > > So the next question is how do the idle drivers and cpu hotplug > >> > > fit into this picture. Do we need to force the second HT into > >> > > a specific C state before the SMI or something? > >> > > >> > Or you can ask why exactly someone put that SMM trap into _WAK. > >> > > >> > Apparently, it was regarded as necessary or no one would have > >> > bothered. The only reason I can see why it might be regarded as > >> > necessary was that Windows did something Linux doesn't do on that > >> > platform, or, which to me is far more interesting, that Windows didn't > >> > do something actually done by Linux. > >> > > >> > My theory would be that Windows didn't reinitialize the second HT > >> > properly during resume and the trap was added to let SMM do that. If > >> > that's the case, the trap may trigger by the time the second HT > >> > already executes code in Linux and then it will mess up with it and > >> > crash. > >> > > >> > Now, what do idles states have to do with that? IIRC, Windows puts > >> > nonboot CPUs into idle states before suspend, so the SMM code > >> > triggered by the trap may make assumptions about the CPU being in such > >> > a state or similar. > >> > >> BTW I also tried to move the enable_nonboot_cpus() after _WAK, and I > >> tried to boot with nosmp, but neither trick helped. If someone could > >> throw some patches my way to force things into a specific state > >> before suspend/_WAK I'd be happy to test them out. > > > > Ping. Anyone have any ideas what to try here? Would be nice to get this > > machine working again... > > > > -- > > Ville Syrjälä > > Intel OTC > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Ville Syrjälä Intel OTC -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
