linux-kernel - Re: intel_pstate divide error with v3.13-rc4-256-gb7000ad

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sun, 29 Dec 2013 16:04:12 +0100
From:	"Rafael J. Wysocki" <rjw@...ysocki.net>
To:	Kashyap Chamarthy <kchamart@...hat.com>
Cc:	Gleb Natapov <gleb@...nel.org>,
	Josh Boyer <jwboyer@...oraproject.org>,
	One Thousand Gnomes <gnomes@...rguk.ukuu.org.uk>,
	Viresh Kumar <viresh.kumar@...aro.org>,
	Dirk Brandewie <dirk.brandewie@...il.com>,
	"cpufreq@...r.kernel.org" <cpufreq@...r.kernel.org>,
	Linux PM list <linux-pm@...r.kernel.org>,
	"Linux-Kernel@...r. Kernel. Org" <linux-kernel@...r.kernel.org>,
	"Richard W.M. Jones" <rjones@...hat.com>
Subject: Re: intel_pstate divide error with v3.13-rc4-256-gb7000ad

On Sunday, December 29, 2013 01:12:18 PM Kashyap Chamarthy wrote:
> [. . .]
> 
> >> Here's host dmesg: https://bugzilla.kernel.org/attachment.cgi?id=119751
> >>
> >>>> Can you ftrace the failure?
> >>
> >> Can try, need some time (rest of the day I'll be away travelling,
> >> will try to do it over the weekend, and update the Kernel
> >> bugzilla with observations).
> >>
> >>>>
> >>> Ugh, it looks like guest dmesg but there are KVM messages there too ("[
> >>> 281.443662] kvm [2452]: vcpu0 unhandled rdmsr: 0xe8" is unhandled access
> >>> to MSR_IA32_APERF I was talking about above), so I guess this is nested
> >>> guest invocation? 
> >>
> >> Yeah -- sorry, I forgot to note it's in a nested environment :(
> >>
> >>> Does it happen in non nested guest?
> >>
> >> I need to that.
> >>
> >> Note to self: Also try with a newer Kernel on the host.
> > 
> > Please try the patch I posted earlier today when you're at it:
> > 
> > https://patchwork.kernel.org/patch/3411991/
> 
> I applied the patch & tried to build the Kernel, it failed with:
> 
> =======
> .
> .
> .
> Generating a 4096 bit RSA private key
> ............................................................................................................drivers/cpufreq/intel_pstate.c:
> In function 'intel_pstate_init_cpu':
> drivers/cpufreq/intel_pstate.c:617:18: error: 'struct pstate_data' has no member named
> 'current_state'
>   if (!cpu->pstate.current_state) {

My bad, that should have been current_pstate.  Updated patch is appended.

Thanks,
Rafael


---
 drivers/cpufreq/intel_pstate.c |    5 +++++
 1 file changed, 5 insertions(+)

Index: linux-pm/drivers/cpufreq/intel_pstate.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/intel_pstate.c
+++ linux-pm/drivers/cpufreq/intel_pstate.c
@@ -614,6 +614,11 @@ static int intel_pstate_init_cpu(unsigne
 	cpu = all_cpu_data[cpunum];
 
 	intel_pstate_get_cpu_pstates(cpu);
+	if (!cpu->pstate.current_pstate) {
+		all_cpu_data[cpunum] = NULL;
+		kfree(cpu);
+		return -ENODATA;
+	}
 
 	cpu->cpu = cpunum;
 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/