This is a note to let you know that I've just added the patch titled
riscv: hwprobe: do not produce frtace relocation
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
riscv-hwprobe-do-not-produce-frtace-relocation.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f0cb64532dc375910c53c762ed1ced93a5094bd8
Author: Vladimir Isaev <vladimir.isaev@xxxxxxxxxxxxx>
Date: Wed Mar 13 10:35:46 2024 +0300
riscv: hwprobe: do not produce frtace relocation
[ Upstream commit ad14f7ca9f0d9fdf73d1fd61aaf8248d46ffc849 ]
Such relocation causes crash of android linker similar to one
described in commit e05d57dcb8c7
("riscv: Fixup __vdso_gettimeofday broke dynamic ftrace").
Looks like this relocation is added by CONFIG_DYNAMIC_FTRACE which is
disabled in the default android kernel.
Before:
readelf -rW arch/riscv/kernel/vdso/vdso.so:
Relocation section '.rela.dyn' at offset 0xd00 contains 1 entry:
Offset Info Type
0000000000000d20 0000000000000003 R_RISCV_RELATIVE
objdump:
0000000000000c86 <__vdso_riscv_hwprobe@@LINUX_4.15>:
c86: 0001 nop
c88: 0001 nop
c8a: 0001 nop
c8c: 0001 nop
c8e: e211 bnez a2,c92 <__vdso_riscv_hwprobe...
After:
readelf -rW arch/riscv/kernel/vdso/vdso.so:
There are no relocations in this file.
objdump:
0000000000000c86 <__vdso_riscv_hwprobe@@LINUX_4.15>:
c86: e211 bnez a2,c8a <__vdso_riscv_hwprobe...
c88: c6b9 beqz a3,cd6 <__vdso_riscv_hwprobe...
c8a: e739 bnez a4,cd8 <__vdso_riscv_hwprobe...
c8c: ffffd797 auipc a5,0xffffd
Also disable SCS since it also should not be available in vdso.
Fixes: aa5af0aa90ba ("RISC-V: Add hwprobe vDSO function and data")
Signed-off-by: Roman Artemev <roman.artemev@xxxxxxxxxxxxx>
Signed-off-by: Vladimir Isaev <vladimir.isaev@xxxxxxxxxxxxx>
Reviewed-by: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>
Reviewed-by: Guo Ren <guoren@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240313085843.17661-1-vladimir.isaev@xxxxxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index 9b517fe1b8a8e..272c431ac5b9f 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -37,6 +37,7 @@ endif
# Disable -pg to prevent insert call site
CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
+CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
# Disable profiling and instrumentation for VDSO code
GCOV_PROFILE := n
