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Date:   Thu, 23 Mar 2023 11:34:23 -0700
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Sachin Sant <sachinp@linux.ibm.com>
Cc:     linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        linux-next@vger.kernel.org,
        open list <linux-kernel@vger.kernel.org>,
        Zqiang <qiang1.zhang@intel.com>
Subject: Re: [next-20230322] Kernel WARN at kernel/workqueue.c:3182
 (rcutorture)
Message-ID: <ae015179-03b5-4e4b-86dd-cbab75230c7f@paulmck-laptop>
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 <233B28DA-70DD-4AD8-9C72-1FFCA6EFE56D@linux.ibm.com>
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On Thu, Mar 23, 2023 at 11:00:59PM +0530, Sachin Sant wrote:
> 
> >> [ 3629.243407] NIP [00007fff8cd39558] 0x7fff8cd39558
> >> [ 3629.243410] LR [000000010d800398] 0x10d800398
> >> [ 3629.243413] --- interrupt: c00
> >> [ 3629.243415] Code: 419dffa4 e93a0078 39400001 552907be 2f890000 7d20579e 0b090000 e95a0078 e91a0080 39200001 7fa85000 7d204f9e <0b090000> 7f23cb78 4bfffd65 0b030000 
> >> [ 3629.243430] ---[ end trace 0000000000000000 ]—
> >> 
> >> These warnings are repeated few times. The LTP test is marked as PASS.
> >> 
> >> Git bisect point to the following patch
> >> commit f46a5170e6e7d5f836f2199fe82cdb0b4363427f
> >>    srcu: Use static init for statically allocated in-module srcu_struct
> > 
> > Hello, Sachin, and it looks like you hit something that Zqiang and I
> > have been tracking down.  I am guessing that you were using modprobe
> > and rmmod to make this happen, and that this happened at rmmod time.
> > 
> Yes, the LTP test script rcu_torture.sh relies on modprobe to load/unload
> the rcutorture module.
> 
> > Whatever the reproducer, does the following patch help?
> 
> Thank you for the patch. Yes, with this patch applied, the test completes
> successfully without the reported warning.

Very good, thank you!  May we have your Tested-by?

							Thanx, Paul