Re: [Xen-devel] Regression, host crash with 4.5rc1

2015-03-02 Thread Jan Beulich
On 27.02.15 at 18:50, len.br...@intel.com wrote: If this issue were to happen on Linux/bare-metal, this is how I'd debug it. Hopefully some of this will translate to Xen in one way or another. Sadly not really - the kernel plays only a minor role (forwarding ACPI data to the hypervisor) in

Re: [Xen-devel] Regression, host crash with 4.5rc1

2015-02-27 Thread Dugger, Donald D
2:28 AM To: Steve Freitas; Dugger, Donald D; Nakajima, Jun Cc: xen-devel@lists.xen.org; Don Slutz Subject: Re: [Xen-devel] Regression, host crash with 4.5rc1 On 27.11.14 at 06:29, sfl...@ihonk.com wrote: On 11/25/2014 03:00 AM, Jan Beulich wrote: Okay, so it's not really the mwait-idle driver

Re: [Xen-devel] Regression, host crash with 4.5rc1

2015-02-27 Thread Brown, Len
(Please forgive my lack of Xen-fu knowledge in advance) If this issue were to happen on Linux/bare-metal, this is how I'd debug it. Hopefully some of this will translate to Xen in one way or another. dmesg | grep idle will tell us what idle driver is running (on Dom0 kernel) and if it is

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-12-03 Thread Dugger, Donald D
; Dugger, Donald D; Nakajima, Jun Cc: xen-devel@lists.xen.org; Don Slutz Subject: Re: [Xen-devel] Regression, host crash with 4.5rc1 On 27.11.14 at 06:29, sfl...@ihonk.com wrote: On 11/25/2014 03:00 AM, Jan Beulich wrote: Okay, so it's not really the mwait-idle driver causing the regression

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-28 Thread Steve Freitas
On 11/27/2014 01:27 AM, Jan Beulich wrote: This was precisely the reason why I told you that the numbering differs (and is confusing and has nothing to do with actual C state numbers): What max_cstate refers to in the mwait-idle driver is what above is listed as type[Cx], i.e. the state at index

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-28 Thread Steve Freitas
On Nov 28, 2014, at 00:50, Jan Beulich jbeul...@suse.com wrote: On 28.11.14 at 09:24, sfl...@ihonk.com wrote: And with 6 errata documented it's not all that unlikely that there's a 7th one with MONITOR/MWAIT behavior. The commit you bisected to (and which you had verified to be the culprit

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-27 Thread Jan Beulich
On 27.11.14 at 06:29, sfl...@ihonk.com wrote: On 11/25/2014 03:00 AM, Jan Beulich wrote: Okay, so it's not really the mwait-idle driver causing the regression, but it is C-state related. Hence we're now down to seeing whether all or just the deeper C states are affected, i.e. I now need to

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-26 Thread Steve Freitas
On 11/25/2014 03:00 AM, Jan Beulich wrote: Okay, so it's not really the mwait-idle driver causing the regression, but it is C-state related. Hence we're now down to seeing whether all or just the deeper C states are affected, i.e. I now need to ask you to play with max_cstate=. For that you'll

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-25 Thread Jan Beulich
On 24.11.14 at 23:17, sfl...@ihonk.com wrote: I'm combining this action with your patch, see below. Please let me know if this was incorrect. Thanks, that's perfectly fine. (XEN) 'c' pressed - printing ACPI Cx structures (XEN) ==cpu0== (XEN) active state:C0 (XEN) max_cstate:

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-25 Thread Steve Freitas
On 11/25/2014 12:16 AM, Jan Beulich wrote: (XEN) 'c' pressed - printing ACPI Cx structures (XEN) ==cpu0== (XEN) active state:C0 (XEN) max_cstate:C7 (XEN) states: (XEN) C1:type[C1] latency[001] usage[5664] method[ FFH] duration[4042540627] (XEN) C2:type[C3]

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-25 Thread Jan Beulich
On 25.11.14 at 10:38, sfl...@ihonk.com wrote: On 11/25/2014 12:16 AM, Jan Beulich wrote: Interesting, so other than for me (perhaps due to other patches I have in my tree) the change resulted in C states now being used again despite mwait-idle=0, which is good. Question now is - with this

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-24 Thread Jan Beulich
On 23.11.14 at 02:28, sfl...@ihonk.com wrote: With mwait-idle=0: (XEN) 'c' pressed - printing ACPI Cx structures (XEN) ==cpu0== (XEN) active state: C0 (XEN) max_cstate: C7 (XEN) states: (XEN) C1: type[C1] latency[001] usage[] method[ FFH]

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-24 Thread Steve Freitas
On Nov 24, 2014, at 00:45, Jan Beulich jbeul...@suse.com wrote: On 23.11.14 at 02:28, sfl...@ihonk.com wrote: With mwait-idle=0: (XEN) 'c' pressed - printing ACPI Cx structures (XEN) ==cpu0== (XEN) active state: C0 (XEN) max_cstate: C7 (XEN) states: (XEN)

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-24 Thread Jan Beulich
On 24.11.14 at 10:08, sfl...@ihonk.com wrote: On Nov 24, 2014, at 00:45, Jan Beulich jbeul...@suse.com wrote: On 23.11.14 at 02:28, sfl...@ihonk.com wrote: With mwait-idle=0: (XEN) 'c' pressed - printing ACPI Cx structures (XEN) ==cpu0== (XEN) active state: C0 (XEN)

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-21 Thread Jan Beulich
On 20.11.14 at 21:07, sfl...@ihonk.com wrote: Running with mwait-idle=0 solves (hides?) the problem. Next step is to fiddle with the C states? So this also prompted me to go over the list of errata. Just to confirm - your CPU is family 6 model 44? What stepping? And what nominal frequency?

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-20 Thread Jan Beulich
On 20.11.14 at 02:23, sfl...@ihonk.com wrote: On 11/17/2014 23:54, Jan Beulich wrote: Another thing - now that serial logging appears to be working for you, did you try whether the host, once hung, still reacts to serial input (perhaps force input to go to Xen right at boot via the

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-20 Thread Steve Freitas
Hi Jan, Thanks for all your help so far! Here's my latest update. On 11/17/2014 23:54, Jan Beulich wrote: Plus, without said adjustment, first just disable the MWAIT CPU idle driver (mwait-idle=0) and then, if that didn't make a difference, use of C states altogether (cpuidle=0). If any of

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-19 Thread Steve Freitas
On 11/17/2014 23:54, Jan Beulich wrote: On 17.11.14 at 20:21, sfl...@ihonk.com wrote: Okay, I did a bisection and was not able to correlate the above error message with the problem I'm seeing. Not saying it's not related, but I had plenty of successful test runs in the presence of that error.

Re: [Xen-devel] Regression, host crash with 4.5rc1

2014-11-10 Thread Steve Freitas
On 11/10/2014 0:51, Jan Beulich wrote: On 10.11.14 at 09:03, sfl...@ihonk.com wrote: Sorry for the delay, took some debugging on another computer to get serial logging working. Due to its size, I've posted the entire log of a crashed session here: http://pastebin.com/AiPHUZRH In this case I