linux-kernel - Wrong module .text address in 4.16.0

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Message-Id: <7e17e3b1-25c3-cb61-ae94-dcbb1bf3473e@linux.ibm.com>
Date:   Mon, 16 Apr 2018 07:51:47 +0200
From:   Thomas-Mich Richter <tmricht@...ux.ibm.com>
To:     Christian Borntraeger <borntraeger@...ibm.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Cc:     Martin Schwidefsky <schwidefsky@...ibm.com>,
        Hendrik Brueckner <brueckner@...ux.vnet.ibm.com>,
        Heiko Carstens <heiko.carstens@...ibm.com>
Subject: Wrong module .text address in 4.16.0

I just installed 4.16.0 and discovered the module .text address is
wrong. It happens on s390 and x86 platforms. I have not tested others.

Here is the issue, I have used module qeth_l2 on s390 which is the
ethernet device driver:

root@...lp76 ~]# lsmod
Module                  Size  Used by
qeth_l2                94208  1
...

[root@...lp76 ~]# cat /proc/modules | egrep '^qeth_l2'
qeth_l2 94208 1 - Live 0x000003ff80401000   <---- This is the correct address in memory
[root@...lp76 ~]# cat /sys/module/qeth_l2/sections/.text 
0x0000000018ea8363      <---- This is the wrong address
[root@...lp76 ~]# 

File /sys/module/qeth_l2/sections/.text displays a very strange
address which is definitely wrong. It should be something like
0x000003ff80401xxx.

Same on x86.

I have checked file kernel/module.c function add_sect_attrs()
and it calls module_sect_show() when the sysfs file is read.
And module_sect_show() uses 

  sprintf(buf, "0x%pK\n", (void *)sattr->address);

and my sysctl setting should be correct:
[root@...lp76 linux]# sysctl -a | fgrep kernel.kptr_restrict
kernel.kptr_restrict = 0
[root@...lp76 linux]#

I wonder if somebody else has seen this issue?
Ideas how to fix this?

Thanks
-- 
Thomas Richter, Dept 3303, IBM LTC Boeblingen Germany
--
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Geschäftsführung: Dirk Wittkopp
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