From:   Tom Saeger <tom.saeger@oracle.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Naresh Kamboju <naresh.kamboju@linaro.org>,
        John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>,
        Rich Felker <dalias@libc.org>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Ard Biesheuvel <ardb@kernel.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Dennis Gilmore <dennis@ausil.us>,
        Palmer Dabbelt <palmer@rivosinc.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        Tom Saeger <tom.saeger@oracle.com>, stable@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org
Subject: [PATCH 5.15 fix build id for arm64 4/5] s390: define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36
Date:   Fri, 27 Jan 2023 13:40:10 -0700
Message-Id: <178abde2262b22100aac5de018e92a6dc9d5bce6.1674851705.git.tom.saeger@oracle.com>
In-Reply-To: <cover.1674851705.git.tom.saeger@oracle.com>
References: <cover.1674851705.git.tom.saeger@oracle.com>
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ihD7Sk27bRjEphqziys2YR7cKjgLze5HKcYYe7eumlNK4XTj/fZH2nuUObDG?=
 =?us-ascii?Q?YcWsp+xSHrb0JDQnJu+/F71eAC90IAccaxj9ACyKCmzHloosqzV/BwQ+007J?=
 =?us-ascii?Q?6GrjjV0ewuVSxKhNalCMW8pAUIhN4a+sCJIL9EwRkuKn5M7ImjWaOkwr9uhs?=
 =?us-ascii?Q?EixVerNXKZc4eoMY2wiUwnVqtXJ1u73FGBZSHS0jxh+/xqyc0sRqbYLoHPfO?=
 =?us-ascii?Q?Lmb516gI2E7qYbnfKhMK6Q3TUCox11f2gDP/J/3V61Q1pPePRQr5ewMzZZlU?=
 =?us-ascii?Q?1mvvfqMVFXn8Lmskl9NMENHoSqYj+iiqkaAbtUUyamM/IBwbaXSJVfW0LTtm?=
 =?us-ascii?Q?wzRxgshq+MwZHOyC1geRGyrnrc6uaseVL48p9XYfwT1a8ixAaohGh4Uuhvzr?=
 =?us-ascii?Q?jCub/MFl+yzgrY4/SVpvHIXaZxi6DtPHBYL5iKhSyc16Oqmz05WcvGK0a9ig?=
 =?us-ascii?Q?bvsTK5ruuZpzx5hXaebmb1NHm2gXrYq2kN/Pp4WPNmnBl1r0SC15WPlE5SSt?=
 =?us-ascii?Q?zAYHj+uDUGJ3PJgaWRxKJodGcwyhoWr8X2m4GdLWvG0St8b//9DEYNs/xznf?=
 =?us-ascii?Q?UiqYZhqlLis5WgIQ7AzwDSeoDZDsfwyjVMsVJfSUbSZmkQwk/UPUvHLPjOmn?=
 =?us-ascii?Q?Umq40WYj4+B/Cunuo5j+Jpo5QOYRNPrLxRPA+cglphD5gj5fq+Qpwr7KgqGW?=
 =?us-ascii?Q?gBSN5sMu2nDqz5rJ4J5QB1h7uGo7oW3pTedhDcJFVpRqPoeH/eHRgGoyYF/t?=
 =?us-ascii?Q?5T7sdeCLE9sMvpX/rzX7Y1kRCFhzik02Po5QFNcrRg33g4epN3jhWPswYsbf?=
 =?us-ascii?Q?cEeTWEw8OQvN7YCJKIgb5Kr3h7ht+qpxlhz9WMHKLBC7zeERdU/My5L7r773?=
 =?us-ascii?Q?odGIquZDzKk9rYZMQ7Z9Gr67ZS9HOF5LRJ1ifDInU3Z7prk2lTTrsctyzt8S?=
 =?us-ascii?Q?4ZmSN8fUgno+AIqpmgfqbVQ9HgaWgr8ceIFQRtUh/rWn+WLQVWtid8ZLluEz?=
 =?us-ascii?Q?CGMOvjZNAgOFO35u1vteo/PPWxU7v/KmMH3sgso8LGSHYmEk0hD5g8OXonIK?=
 =?us-ascii?Q?qMLMmOdTHe2sUr1C3b4C/hhLnsPaZ3T9N0ig7f6YxsoeAyW6teEYnxp+VI9B?=
 =?us-ascii?Q?j6mBKCFxyKddFWWqEk/J8FMptGk0v4AnwsX5fTGZlKSlEPnAq8yIGqXIw+Nm?=
 =?us-ascii?Q?NKafnc9h9Nug1PQouyU88vMgLaVhdAe0+gNBi/zXanq/pBSdHYtxmlx5aEpk?=
 =?us-ascii?Q?qFaFAhOvgT71tQw9Z1QzilMkOgP7+l1SahErUFMxFgmIAG8X3wYER5Up3Z8G?=
 =?us-ascii?Q?ePOA+IQIQu31YCClg3iDgVDcnKDQJeDxxhwKiYulsyxl6P8X4xmcJ30biUZ5?=
 =?us-ascii?Q?gWTYRXuZ7JTYdXBlZCLwC2hy5W5KuWd+G3iC5LCW6xsw4mYLRfG2lsCbql9E?=
 =?us-ascii?Q?5xRGtNekg226S92LKnYs37hk1bo2SwQCbHpoQpx/11adLIYn04mSP0gFjxCR?=
 =?us-ascii?Q?cpZKdYABKJ5ZnrNgRJ9oY3ewEah4q16O2V2GaJWrajlDHvZkEhMp9fVpQaY8?=
 =?us-ascii?Q?SpGHf/PyqdN7vYaa5lZRkL/r+Id8O2bVFMGF5NaQFIX0dPmjKFizoy4EDVp7?=
 =?us-ascii?Q?13yPMgrrqTXqUHGgvWreOLE=3D?=
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: =?us-ascii?Q?xVU8w83qXbU5M9dokscxK2JH5bSeiATdDj7BU6ybz4iKdtHYHVjwR8LwcENY?=
 =?us-ascii?Q?EMoA1v1vcZTA4MRne+PeLogmMl14A3Wf72jh5pJ4sJzF+2IadUArGdOvoxtA?=
 =?us-ascii?Q?Le1HzPPhqwTFnkChzbhapTkSpimX9zMwOC0GJzoskkxcjXKvh4lYWouhPh6n?=
 =?us-ascii?Q?t8u7CGQzxlwaD3gJVKBIPly5cDdBqMOuEpPnwf1dP3Q5XR9AzMAAcupSrY4Z?=
 =?us-ascii?Q?gFmiSGpt6K1dzuSrnZjOc2v5TuoZbFJ6u6GmkJOup9U+zqJ1FC8dKdipSDRN?=
 =?us-ascii?Q?Xcb2q+EelQD+nbyic523kiHT9KyHneE0CFEp4YMY4XNgAByUw+ThfRpsZ10S?=
 =?us-ascii?Q?2E533xyAgn6Shqgf9RONeCyPZcHtUFkgyLgY5hH5UvDykgE/FdQZmWfpVm5F?=
 =?us-ascii?Q?YaRdUUwIsl+eItTxSJtvewFHkoQXDOezyE37vJOpNnxEjHmvBRTb73XdUuAb?=
 =?us-ascii?Q?E3yloNr+h3AZgboyym5ZGZe3vs8BVOxNneejsQiCkhnj80GLqBnzUbj3JEr0?=
 =?us-ascii?Q?Id6n0y2Wpx7txrjKpbq7dJ2QJbfhDfXJKBhdLtvZfPkJG3WrhPSHpOpIm+mx?=
 =?us-ascii?Q?p0jBrD6NdVhkOowKZ0dnh5gvlP8GyAnLCyNS6oHU34+uBV/FmY0VBZTgdl+U?=
 =?us-ascii?Q?I/3YBjZsonNdbl6hqcwRFIhANxARnTgQgRPz6ypt4j03bJK+pECudZnYdezU?=
 =?us-ascii?Q?UoGbpbmeWzlPwQQmRoRdxzA7EBmZwcDMOM4hOSAa7pelqt85nMqMIpjt6RkL?=
 =?us-ascii?Q?DMv6X2haQzXglv/Fg76R4ilFX+F0PBEpGGnXoeOHjtQx60XAP7lTX3oWMVpZ?=
 =?us-ascii?Q?M5aQWQq+etqKN2sG30wvTU+bY8ZVgGKWKrKZ4V3peG332AKM/bjCnCzOXY1g?=
 =?us-ascii?Q?pEZtsPz3O36ajoC/oadPmPNMAzkd3aZQbF5OJN4KD1JjA/cd9nF8ebVPyzKv?=
 =?us-ascii?Q?CwAhkRb/dNX5u/dvx2QsygTLDAA0m9HcvL1hEYfGgRBt1GO5tfxF3/+c4yxt?=
 =?us-ascii?Q?ndQOBe3O5Xkk3iSVxOOiFhXUdPDHJ0OGUhau7mb5+FaT8VCwF3J9Z1D3Gy1x?=
 =?us-ascii?Q?36mG4sopzEgKZh9hWnVR0xDMznWvOQ=3D=3D?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 80453183-c155-4cff-16f6-08db00a6ba82
X-MS-Exchange-CrossTenant-AuthSource: BY5PR10MB3794.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Jan 2023 20:40:29.8747
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: awxF1l1rojWfDbefa5xHk3/4Tkkkdtmh5K0bNriJSBbuP0tAGun64o7msi02QZiCCPpljcyqeRkUELf3YKIPXQ==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR10MB7459
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.219,Aquarius:18.0.930,Hydra:6.0.562,FMLib:17.11.122.1
 definitions=2023-01-27_13,2023-01-27_01,2022-06-22_01
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 mlxscore=0 spamscore=0
 bulkscore=0 mlxlogscore=999 malwarescore=0 adultscore=0 suspectscore=0
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2212070000
 definitions=main-2301270190
X-Proofpoint-ORIG-GUID: NaILmeKXaWiDE97CURorLlDwZUJxmHQM
X-Proofpoint-GUID: NaILmeKXaWiDE97CURorLlDwZUJxmHQM
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

From: Masahiro Yamada <masahiroy@kernel.org>

commit a494398bde273143c2352dd373cad8211f7d94b2 upstream.

Nathan Chancellor reports that the s390 vmlinux fails to link with
GNU ld < 2.36 since commit 99cb0d917ffa ("arch: fix broken BuildID
for arm64 and riscv").

It happens for defconfig, or more specifically for CONFIG_EXPOLINE=y.

  $ s390x-linux-gnu-ld --version | head -n1
  GNU ld (GNU Binutils for Debian) 2.35.2
  $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- allnoconfig
  $ ./scripts/config -e CONFIG_EXPOLINE
  $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- olddefconfig
  $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu-
  `.exit.text' referenced in section `.s390_return_reg' of drivers/base/dd.o: defined in discarded section `.exit.text' of drivers/base/dd.o
  make[1]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
  make: *** [Makefile:1252: vmlinux] Error 2

arch/s390/kernel/vmlinux.lds.S wants to keep EXIT_TEXT:

        .exit.text : {
                EXIT_TEXT
        }

But, at the same time, EXIT_TEXT is thrown away by DISCARD because
s390 does not define RUNTIME_DISCARD_EXIT.

I still do not understand why the latter wins after 99cb0d917ffa,
but defining RUNTIME_DISCARD_EXIT seems correct because the comment
line in arch/s390/kernel/vmlinux.lds.S says:

        /*
         * .exit.text is discarded at runtime, not link time,
         * to deal with references from __bug_table
         */

Nathan also found that binutils commit 21401fc7bf67 ("Duplicate output
sections in scripts") cured this issue, so we cannot reproduce it with
binutils 2.36+, but it is better to not rely on it.

Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
Link: https://lore.kernel.org/all/Y7Jal56f6UBh1abE@dev-arch.thelio-3990X/
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20230105031306.1455409-1-masahiroy@kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Tom Saeger <tom.saeger@oracle.com>
---
 arch/s390/kernel/vmlinux.lds.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index b508ccad4856..7582d5fa4cc1 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -17,6 +17,8 @@
 /* Handle ro_after_init data on our own. */
 #define RO_AFTER_INIT_DATA
 
+#define RUNTIME_DISCARD_EXIT
+
 #define EMITS_PT_NOTE
 
 #include <asm-generic/vmlinux.lds.h>
-- 
2.39.1