linux-stable.git/arch/powerpc/kernel/vmlinux.lds.S, branch v6.1.78 Linux kernel stable tree powerpc/vmlinux.lds: Don't discard .rela* for relocatable builds 2023-02-25T10:25:42+00:00 Michael Ellerman mpe@ellerman.id.au 2023-01-05T11:28:36+00:00 a783d7f7cb957c5b652b5456020ece4e39f61a29 commit 07b050f9290ee012a407a0f64151db902a1520f5 upstream. Relocatable kernels must not discard relocations, they need to be processed at runtime. As such they are included for CONFIG_RELOCATABLE builds in the powerpc linker script (line 340). However they are also unconditionally discarded later in the script (line 414). Previously that worked because the earlier inclusion superseded the discard. However commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") introduced an earlier use of DISCARD as part of the RO_DATA macro (line 137). With binutils < 2.36 that causes the DISCARD directives later in the script to be applied earlier, causing .rela* to actually be discarded at link time, leading to build warnings and a kernel that doesn't boot: ld: warning: discarding dynamic section .rela.init.rodata Fix it by conditionally discarding .rela* only when CONFIG_RELOCATABLE is disabled. Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230105132349.384666-2-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tom Saeger <tom.saeger@oracle.com> 
commit 07b050f9290ee012a407a0f64151db902a1520f5 upstream.

Relocatable kernels must not discard relocations, they need to be
processed at runtime. As such they are included for CONFIG_RELOCATABLE
builds in the powerpc linker script (line 340).

However they are also unconditionally discarded later in the
script (line 414). Previously that worked because the earlier inclusion
superseded the discard.

However commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and
riscv") introduced an earlier use of DISCARD as part of the RO_DATA
macro (line 137). With binutils < 2.36 that causes the DISCARD
directives later in the script to be applied earlier, causing .rela* to
actually be discarded at link time, leading to build warnings and a
kernel that doesn't boot:

  ld: warning: discarding dynamic section .rela.init.rodata

Fix it by conditionally discarding .rela* only when CONFIG_RELOCATABLE
is disabled.

Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230105132349.384666-2-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tom Saeger <tom.saeger@oracle.com>
powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT 2023-02-25T10:25:42+00:00 Michael Ellerman mpe@ellerman.id.au 2023-01-05T11:05:04+00:00 9c87fd4a3044b6950179669fbdde624e881bc669 commit 4b9880dbf3bdba3a7c56445137c3d0e30aaa0a40 upstream. The powerpc linker script explicitly includes .exit.text, because otherwise the link fails due to references from __bug_table and __ex_table. The code is freed (discarded) at runtime along with .init.text and data. That has worked in the past despite powerpc not defining RUNTIME_DISCARD_EXIT because DISCARDS appears late in the powerpc linker script (line 410), and the explicit inclusion of .exit.text earlier (line 280) supersedes the discard. However commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") introduced an earlier use of DISCARD as part of the RO_DATA macro (line 136). With binutils < 2.36 that causes the DISCARD directives later in the script to be applied earlier [1], causing .exit.text to actually be discarded at link time, leading to build errors: '.exit.text' referenced in section '__bug_table' of crypto/algboss.o: defined in discarded section '.exit.text' of crypto/algboss.o '.exit.text' referenced in section '__ex_table' of drivers/nvdimm/core.o: defined in discarded section '.exit.text' of drivers/nvdimm/core.o Fix it by defining RUNTIME_DISCARD_EXIT, which causes the generic DISCARDS macro to not include .exit.text at all. 1: https://lore.kernel.org/lkml/87fscp2v7k.fsf@igel.home/ Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230105132349.384666-1-mpe@ellerman.id.au Signed-off-by: Tom Saeger <tom.saeger@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 4b9880dbf3bdba3a7c56445137c3d0e30aaa0a40 upstream.

The powerpc linker script explicitly includes .exit.text, because
otherwise the link fails due to references from __bug_table and
__ex_table. The code is freed (discarded) at runtime along with
.init.text and data.

That has worked in the past despite powerpc not defining
RUNTIME_DISCARD_EXIT because DISCARDS appears late in the powerpc linker
script (line 410), and the explicit inclusion of .exit.text
earlier (line 280) supersedes the discard.

However commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and
riscv") introduced an earlier use of DISCARD as part of the RO_DATA
macro (line 136). With binutils < 2.36 that causes the DISCARD
directives later in the script to be applied earlier [1], causing
.exit.text to actually be discarded at link time, leading to build
errors:

  '.exit.text' referenced in section '__bug_table' of crypto/algboss.o: defined in
  discarded section '.exit.text' of crypto/algboss.o
  '.exit.text' referenced in section '__ex_table' of drivers/nvdimm/core.o: defined in
  discarded section '.exit.text' of drivers/nvdimm/core.o

Fix it by defining RUNTIME_DISCARD_EXIT, which causes the generic
DISCARDS macro to not include .exit.text at all.

1: https://lore.kernel.org/lkml/87fscp2v7k.fsf@igel.home/

Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230105132349.384666-1-mpe@ellerman.id.au
Signed-off-by: Tom Saeger <tom.saeger@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc: Fix writable sections being moved into the rodata region 2022-11-16T10:37:14+00:00 Nicholas Piggin npiggin@gmail.com 2022-11-16T04:39:53+00:00 eb761a1760bf30cf64e98ee8d914866e62ec9e8a .data.rel.ro* catches .data.rel.root_cpuacct, and the kernel crashes on a store in css_clear_dir. At least we know read-only data protection is working... Fixes: b6adc6d6d3272 ("powerpc/build: move .data.rel.ro, .sdata2 to read-only") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20221116043954.3307852-1-npiggin@gmail.com 
.data.rel.ro*  catches .data.rel.root_cpuacct, and the kernel crashes on
a store in css_clear_dir. At least we know read-only data protection is
working...

Fixes: b6adc6d6d3272 ("powerpc/build: move .data.rel.ro, .sdata2 to read-only")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221116043954.3307852-1-npiggin@gmail.com
powerpc: Drops STABS_DEBUG from linker scripts 2022-09-30T08:35:52+00:00 Michael Ellerman mpe@ellerman.id.au 2022-09-28T13:09:51+00:00 7673335e2a0b8e68a2a238773a34e287a089a8fe No toolchain we support should be generating stabs debug information anymore. Drop the sections entirely from our linker scripts. We removed all the manual stabs annotations in commit 12318163737c ("powerpc/32: Remove remaining .stabs annotations"). Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220928130951.1732983-1-mpe@ellerman.id.au 
No toolchain we support should be generating stabs debug information
anymore. Drop the sections entirely from our linker scripts.

We removed all the manual stabs annotations in commit
12318163737c ("powerpc/32: Remove remaining .stabs annotations").

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220928130951.1732983-1-mpe@ellerman.id.au
powerpc: Remove CONFIG_PPC_FSL_BOOK3E 2022-09-26T13:00:13+00:00 Christophe Leroy christophe.leroy@csgroup.eu 2022-09-19T17:01:38+00:00 3e7318584dfec11992f3ac45658c4bc1210b3778 CONFIG_PPC_FSL_BOOK3E is redundant with CONFIG_PPC_E500. Remove it. And rename five files accordingly. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Rename include guards to match new file names] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/795cb93b88c9a0279289712e674f39e3b108a1b4.1663606876.git.christophe.leroy@csgroup.eu 
CONFIG_PPC_FSL_BOOK3E is redundant with CONFIG_PPC_E500.

Remove it.

And rename five files accordingly.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Rename include guards to match new file names]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/795cb93b88c9a0279289712e674f39e3b108a1b4.1663606876.git.christophe.leroy@csgroup.eu
powerpc: Remove CONFIG_PPC_BOOK3E 2022-09-26T13:00:13+00:00 Christophe Leroy christophe.leroy@csgroup.eu 2022-09-19T17:01:33+00:00 e0d68273d7069537701bb91c51d90d1e12aacc33 CONFIG_PPC_BOOK3E is redundant with CONFIG_PPC_BOOK3E_64. The later is more explicit about the fact that it's a 64 bits target. Remove CONFIG_PPC_BOOK3E. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/5d0891490813c19cdcfc04678f512ea68cba3e64.1663606876.git.christophe.leroy@csgroup.eu 
CONFIG_PPC_BOOK3E is redundant with CONFIG_PPC_BOOK3E_64.

The later is more explicit about the fact that it's a 64 bits target.

Remove CONFIG_PPC_BOOK3E.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5d0891490813c19cdcfc04678f512ea68cba3e64.1663606876.git.christophe.leroy@csgroup.eu
powerpc/64/build: merge .got and .toc input sections 2022-09-26T10:58:17+00:00 Nicholas Piggin npiggin@gmail.com 2022-09-16T04:07:54+00:00 1e9eca485a840985a663080eb049c420272d4bdd Follow the binutils ld internal linker script and merge .got and .toc input sections in the .got output section. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220916040755.2398112-7-npiggin@gmail.com 
Follow the binutils ld internal linker script and merge .got and .toc
input sections in the .got output section.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220916040755.2398112-7-npiggin@gmail.com
powerpc/64/build: only include .opd with ELFv1 2022-09-26T10:58:17+00:00 Nicholas Piggin npiggin@gmail.com 2022-09-16T04:07:53+00:00 c787fed11890babda1e4882cd3b6efaf412e1bde ELFv2 does not use function descriptors so .opd is not required. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220916040755.2398112-6-npiggin@gmail.com 
ELFv2 does not use function descriptors so .opd is not required.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220916040755.2398112-6-npiggin@gmail.com
powerpc/build: move .data.rel.ro, .sdata2 to read-only 2022-09-26T10:58:17+00:00 Nicholas Piggin npiggin@gmail.com 2022-09-16T04:07:52+00:00 b6adc6d6d327229d75607a948cde2349d317f366 .sdata2 is a readonly small data section for ppc32, and .data.rel.ro is data that needs relocating but is read-only after that so these can both be moved to the read only memory region. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220916040755.2398112-5-npiggin@gmail.com 
.sdata2 is a readonly small data section for ppc32, and .data.rel.ro
is data that needs relocating but is read-only after that so these
can both be moved to the read only memory region.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220916040755.2398112-5-npiggin@gmail.com
powerpc/build: move got, toc, plt, branch_lt sections to read-only 2022-09-26T10:58:17+00:00 Nicholas Piggin npiggin@gmail.com 2022-09-16T04:07:51+00:00 f21ba4499a15b76ad6013ca0a60873dbcf164c7b This moves linker-related tables from .data to read-only area. Relocations are performed at early boot time before memory is protected, after which there should be no modifications required. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Don't use SPECIAL as reported by lkp@intel.com] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220916040755.2398112-4-npiggin@gmail.com 
This moves linker-related tables from .data to read-only area.
Relocations are performed at early boot time before memory is protected,
after which there should be no modifications required.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Don't use SPECIAL as reported by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220916040755.2398112-4-npiggin@gmail.com