This is a note to let you know that I've just added the patch titled
riscv: fix detection of toolchain Zicbom support
to the 6.0-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-fix-detection-of-toolchain-zicbom-support.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 749ab02eb698ee8a549b0e8667022a6528e19b20
Author: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Date: Thu Oct 6 18:35:20 2022 +0100
riscv: fix detection of toolchain Zicbom support
[ Upstream commit b8c86872d1dc171d8f1c137917d6913cae2fa4f2 ]
It is not sufficient to check if a toolchain supports a particular
extension without checking if the linker supports that extension too.
For example, Clang 15 supports Zicbom but GNU bintutils 2.35.2 does
not, leading build errors like so:
riscv64-linux-gnu-ld: -march=rv64i2p0_m2p0_a2p0_c2p0_zicbom1p0_zihintpause2p0: Invalid or unknown z ISA extension: 'zicbom'
Convert CC_HAS_ZICBOM to TOOLCHAIN_HAS_ZICBOM & check if the linker
also supports Zicbom.
Reported-by: Kevin Hilman <khilman@xxxxxxxxxxxx>
Link: https://github.com/ClangBuiltLinux/linux/issues/1714
Link: https://storage.kernelci.org/next/master/next-20220920/riscv/defconfig+CONFIG_EFI=n/clang-16/logs/kernel.log
Fixes: 1631ba1259d6 ("riscv: Add support for non-coherent devices using zicbom extension")
Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Reviewed-by: Heiko Stuebner <heiko@xxxxxxxxx>
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221006173520.1785507-2-conor@xxxxxxxxxx
[Palmer: Check for ld-2.38, not 2.39, as 2.38 no longer errors.]
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index cea22ccb57cb..e646298d2d65 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -402,14 +402,16 @@ config RISCV_ISA_SVPBMT
If you don't know what to do here, say Y.
-config CC_HAS_ZICBOM
+config TOOLCHAIN_HAS_ZICBOM
bool
- default y if 64BIT && $(cc-option,-mabi=lp64 -march=rv64ima_zicbom)
- default y if 32BIT && $(cc-option,-mabi=ilp32 -march=rv32ima_zicbom)
+ default y
+ depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicbom)
+ depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicbom)
+ depends on LLD_VERSION >= 150000 || LD_VERSION >= 23800
config RISCV_ISA_ZICBOM
bool "Zicbom extension support for non-coherent DMA operation"
- depends on CC_HAS_ZICBOM
+ depends on TOOLCHAIN_HAS_ZICBOM
depends on !XIP_KERNEL && MMU
select RISCV_DMA_NONCOHERENT
select RISCV_ALTERNATIVE
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
index e7d52a2301e2..d1dbbe0fb0f8 100644
--- a/arch/riscv/Makefile
+++ b/arch/riscv/Makefile
@@ -59,8 +59,7 @@ toolchain-need-zicsr-zifencei := $(call cc-option-yn, -march=$(riscv-march-y)_zi
riscv-march-$(toolchain-need-zicsr-zifencei) := $(riscv-march-y)_zicsr_zifencei
# Check if the toolchain supports Zicbom extension
-toolchain-supports-zicbom := $(call cc-option-yn, -march=$(riscv-march-y)_zicbom)
-riscv-march-$(toolchain-supports-zicbom) := $(riscv-march-y)_zicbom
+riscv-march-$(CONFIG_TOOLCHAIN_HAS_ZICBOM) := $(riscv-march-y)_zicbom
# Check if the toolchain supports Zihintpause extension
toolchain-supports-zihintpause := $(call cc-option-yn, -march=$(riscv-march-y)_zihintpause)
