Re: git: bed65d85c631 - main - linux64: Fix the build on arm64 with bti checking

> On 5 Jun 2024, at 16:37, Cy Schubert <Cy.Schubert@cschubert.com> wrote:
> 
> In message <202406050929.4559TFj0027386@gitrepo.freebsd.org>, Andrew Turner 
> wri
> tes:
>> The branch main has been updated by andrew:
>> 
>> URL: https://cgit.FreeBSD.org/src/commit/?id=bed65d85c631c3a8e60a81a15a5a745c
>> 8ef92fbe
>> 
>> commit bed65d85c631c3a8e60a81a15a5a745c8ef92fbe
>> Author:     Andrew Turner <andrew@FreeBSD.org>
>> AuthorDate: 2024-06-04 12:47:52 +0000
>> Commit:     Andrew Turner <andrew@FreeBSD.org>
>> CommitDate: 2024-06-05 09:23:40 +0000
>> 
>>    linux64: Fix the build on arm64 with bti checking
>> 
>>    When we enable checking for BTI on arm64 we need to include an ELF
>>    note in all object files linked into a module.
>> 
>>    As using objcopy from a binary to an ELF object file doesn't add the
>>    note switch to using .incbin from an assembly file. This allows us to
>>    add the needed note without affecting the included object.
>> 
>>    Reviewed by:    imp, kib, emaste
>>    Sponsored by:   Arm Ltd
>>    Differential Revision:  https://reviews.freebsd.org/D45468
>> ---
>> sys/arm64/linux/linux_support.S   |  4 ++++
>> sys/compat/linux/linux_vdso_inc.S | 39 +++++++++++++++++++++++++++++++++++++
>> ++
>> sys/modules/linux64/Makefile      | 17 +++--------------
>> 3 files changed, 46 insertions(+), 14 deletions(-)
>> 
>> diff --git a/sys/arm64/linux/linux_support.S b/sys/arm64/linux/linux_support.
>> S
>> index 151ede7e1c19..3b16583e9d54 100644
>> --- a/sys/arm64/linux/linux_support.S
>> +++ b/sys/arm64/linux/linux_support.S
>> @@ -26,6 +26,8 @@
>>  * SUCH DAMAGE.
>>  */
>> 
>> +#include <sys/elf_common.h>
>> +
>> #include <machine/asm.h>
>> #include <machine/param.h>
>> #include <machine/vmparam.h>
>> @@ -172,3 +174,5 @@ ENTRY(futex_xorl)
>> str w4, [x2]
>> ret
>> END(futex_xorl)
>> +
>> +GNU_PROPERTY_AARCH64_FEATURE_1_NOTE(GNU_PROPERTY_AARCH64_FEATURE_1_VAL)
>> diff --git a/sys/compat/linux/linux_vdso_inc.S b/sys/compat/linux/linux_vdso_
>> inc.S
>> new file mode 100644
>> index 000000000000..af10907f0b60
>> --- /dev/null
>> +++ b/sys/compat/linux/linux_vdso_inc.S
>> @@ -0,0 +1,39 @@
>> +/*-
>> + * SPDX-License-Identifier: BSD-2-Clause
>> + *
>> + * Copyright (C) 2020 Arm Ltd
>> + *
>> + * Redistribution and use in source and binary forms, with or without
>> + * modification, are permitted provided that the following conditions
>> + * are met:
>> + * 1. Redistributions of source code must retain the above copyright
>> + *    notice, this list of conditions and the following disclaimer.
>> + * 2. Redistributions in binary form must reproduce the above copyright
>> + *    notice, this list of conditions and the following disclaimer in the
>> + *    documentation and/or other materials provided with the distribution.
>> + *
>> + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
>> + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>> + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOS
>> E
>> + * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
>> + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIA
>> L
>> + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
>> + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
>> + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRIC
>> T
>> + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
>> + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
>> + * SUCH DAMAGE.
>> + */
>> +
>> + .section .rodata
>> + .globl _binary_linux_vdso_so_o_start
>> +_binary_linux_vdso_so_o_start:
>> + .incbin "linux_vdso.so.o"
>> + .globl _binary_linux_vdso_so_o_end
>> +_binary_linux_vdso_so_o_end:
>> +
>> +#if defined(__aarch64__)
>> +#include <sys/elf_common.h>
>> +#include <machine/asm.h>
>> +GNU_PROPERTY_AARCH64_FEATURE_1_NOTE(GNU_PROPERTY_AARCH64_FEATURE_1_VAL)
>> +#endif
>> diff --git a/sys/modules/linux64/Makefile b/sys/modules/linux64/Makefile
>> index 62e3b464d39f..beed5ec59c4b 100644
>> --- a/sys/modules/linux64/Makefile
>> +++ b/sys/modules/linux64/Makefile
>> @@ -35,7 +35,8 @@ SRCS= linux_dummy_machdep.c \
>> bus_if.h \
>> device_if.h \
>> vnode_if.h \
>> - linux_support.S
>> + linux_support.S \
>> + linux_vdso_inc.S
>> .if ${MACHINE_CPUARCH} == "amd64"
>> SRCS+= linux_dummy_x86.c
>> .endif
>> @@ -47,7 +48,6 @@ SRCS+=  opt_kstack_pages.h opt_nfs.h opt_hwpmc_hooks.h
>> CLEANFILES= linux_assym.h linux_genassym.o linux_locore.o \
>> genassym.o linux_vdso_gtod.o linux_vdso.so.o
>> 
>> -OBJS= linux_vdso.so
>> 
>> linux_assym.h: linux_genassym.o
>> sh ${SYSDIR}/kern/genassym.sh linux_genassym.o > ${.TARGET}
>> @@ -83,18 +83,7 @@ linux_vdso.so.o: linux_locore.o linux_vdso_gtod.o
>> -T${SRCTOP}/sys/${MACHINE}/linux/linux_vdso.lds.s \
>> -o ${.TARGET} ${.ALLSRC:M*.o}
>> 
>> -.if ${MACHINE_CPUARCH} == "aarch64"
>> -OBJCOPY_TARGET=--output-target elf64-littleaarch64 --binary-architecture aar
>> ch64
>> -.elif ${MACHINE_CPUARCH} == "amd64"
>> -OBJCOPY_TARGET=--output-target elf64-x86-64 --binary-architecture i386:x86-6
>> 4
>> -.else
>> -.error ${MACHINE_CPUARCH} not yet supported by linux64
>> -.endif
>> -
>> -linux_vdso.so: linux_vdso.so.o
>> - ${OBJCOPY} --input-target binary ${OBJCOPY_TARGET} \
>> -    linux_vdso.so.o ${.TARGET}
>> - ${STRIPBIN} -N _binary_linux_vdso_so_o_size ${.TARGET}
>> +linux_vdso_inc.o: linux_vdso.so.o
>> 
>> linux_support.o: linux_support.S assym.inc linux_assym.h
>> ${CC} -c -x assembler-with-cpp -DLOCORE ${CFLAGS} \
>> 
> 
> kldload linux64.ko results in the following panic on amd64. Reverting this 
> revision addresses the regression.
> 

Does the attached patch fix it? I didn’t see this when testing.

Andrew