Patch "cpufreq: Avoid crash in resume on SMP without OPP" has been added to the 3.17-stable tree

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

 



This is a note to let you know that I've just added the patch titled

    cpufreq: Avoid crash in resume on SMP without OPP

to the 3.17-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     cpufreq-avoid-crash-in-resume-on-smp-without-opp.patch
and it can be found in the queue-3.17 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 09712f557b31838092e1f22a5f2dd131a843a3de Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Date: Tue, 4 Nov 2014 17:05:25 +0100
Subject: cpufreq: Avoid crash in resume on SMP without OPP

From: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

commit 09712f557b31838092e1f22a5f2dd131a843a3de upstream.

When resuming from s2ram on an SMP system without cpufreq operating
points (e.g. there's no "operating-points" property for the CPU node in
DT, or the platform doesn't use DT yet), the kernel crashes when
bringing CPU 1 online:

    Enabling non-boot CPUs ...
    CPU1: Booted secondary processor
    Unable to handle kernel NULL pointer dereference at virtual address 0000003c
    pgd = ee5e6b00
    [0000003c] *pgd=6e579003, *pmd=6e588003, *pte=00000000
    Internal error: Oops: a07 [#1] SMP ARM
    Modules linked in:
    CPU: 0 PID: 1246 Comm: s2ram Tainted: G        W      3.18.0-rc3-koelsch-01614-g0377af242bb175c8-dirty #589
    task: eeec5240 ti: ee704000 task.ti: ee704000
    PC is at __cpufreq_add_dev.isra.24+0x24c/0x77c
    LR is at __cpufreq_add_dev.isra.24+0x244/0x77c
    pc : [<c0298efc>]    lr : [<c0298ef4>]    psr: 60000153
    sp : ee705d48  ip : ee705d48  fp : ee705d84
    r10: c04e0450  r9 : 00000000  r8 : 00000001
    r7 : c05426a8  r6 : 00000001  r5 : 00000001  r4 : 00000000
    r3 : 00000000  r2 : 00000000  r1 : 20000153  r0 : c0542734

Verify that policy is not NULL before dereferencing it to fix this.

Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Fixes: 8414809c6a1e (cpufreq: Preserve policy structure across suspend/resume)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/cpufreq/cpufreq.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1022,7 +1022,8 @@ static struct cpufreq_policy *cpufreq_po
 
 	read_unlock_irqrestore(&cpufreq_driver_lock, flags);
 
-	policy->governor = NULL;
+	if (policy)
+		policy->governor = NULL;
 
 	return policy;
 }


Patches currently in stable-queue which might be from geert+renesas@xxxxxxxxx are

queue-3.17/cpufreq-avoid-crash-in-resume-on-smp-without-opp.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]