* [PATCH v1 0/2] RISC-V: avoid build issues for clang/llvm-17 with binutils 2.35 @ 2023-02-23 22:05 Conor Dooley 2023-02-23 22:05 ` [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig Conor Dooley 2023-02-23 22:05 ` [PATCH v1 2/2] RISC-V: make TOOLCHAIN_NEEDS_SPEC_20191213 gas only Conor Dooley 0 siblings, 2 replies; 9+ messages in thread From: Conor Dooley @ 2023-02-23 22:05 UTC (permalink / raw) To: palmer; +Cc: conor, Conor Dooley, nathan, naresh.kamboju, linux-riscv, llvm From: Conor Dooley <conor.dooley@microchip.com> Hey, Here's an attempted (interim?) fix for issues on v5.10 due to the presence of zifencei & zicsr in object files. I'm seeing another issue that only appears with ld from binutils-2.35 & not with ld from binutils-2.37 on riscv/for-next: /stuff/toolchains/binutils-2.35/bin/riscv64-linux-gnu-ld: .init.data has both ordered [`__patchable_function_entries' in init/main.o] and unordered [`.meminit.data' in mm/sparse.o] sections /stuff/toolchains/binutils-2.35/bin/riscv64-linux-gnu-ld: final link failed: bad value But that's far far further on in the build than we were getting before these patches. Even if we end up dealing with the emitted strings a different way [1], I think the first patch here has some value in moving the check to Kconfig so that it's far easier to tell if the toolchain does need/use these extensions from someone's build artifacts. Cheers, Conor. 1 - https://lore.kernel.org/linux-riscv/20230223195112.10489-1-palmer@rivosinc.com/ cc: nathan@kernel.org cc: palmer@dabbelt.com cc: naresh.kamboju@linaro.org cc: linux-riscv@lists.infradead.org cc: llvm@lists.linux.dev Conor Dooley (2): RISC-V: move zicsr/zifencei spec version check to Kconfig RISC-V: make TOOLCHAIN_NEEDS_SPEC_20191213 gas only arch/riscv/Kconfig | 9 +++++++++ arch/riscv/Makefile | 5 +---- 2 files changed, 10 insertions(+), 4 deletions(-) -- 2.39.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig 2023-02-23 22:05 [PATCH v1 0/2] RISC-V: avoid build issues for clang/llvm-17 with binutils 2.35 Conor Dooley @ 2023-02-23 22:05 ` Conor Dooley 2023-02-24 16:37 ` Nathan Chancellor 2023-02-23 22:05 ` [PATCH v1 2/2] RISC-V: make TOOLCHAIN_NEEDS_SPEC_20191213 gas only Conor Dooley 1 sibling, 1 reply; 9+ messages in thread From: Conor Dooley @ 2023-02-23 22:05 UTC (permalink / raw) To: palmer; +Cc: conor, Conor Dooley, nathan, naresh.kamboju, linux-riscv, llvm From: Conor Dooley <conor.dooley@microchip.com> Checking whether binutils defaults to using a version of the spec requiring zicsr/zifencei being done in our Makefile is functionally sufficient at present, but makes it harder to tell after the fact which extensions are enabled. By moving it to Kconfig, it's easy to tell from standard build artifacts what has been done & the road is paved for dealing with this differently for both binutils and LLVM. Signed-off-by: Conor Dooley <conor.dooley@microchip.com> --- arch/riscv/Kconfig | 10 ++++++++++ arch/riscv/Makefile | 5 +---- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index cebf0c5f8824..4eb0ef8314b3 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -288,6 +288,16 @@ config ARCH_RV64I endchoice +config TOOLCHAIN_NEEDS_SPEC_20191213 + bool + default y + depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicsr_zifencei) + depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicsr_zifencei) + help + Newer binutils versions default to ISA spec version 20191213 which + moves some instructions from the I extension to the Zicsr and Zifencei + extensions. + # We must be able to map all physical memory into the kernel, but the compiler # is still a bit more efficient when generating code if it's setup in a manner # such that it can only map 2GiB of memory. diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 12d91b0a73d8..7e1267b0e73f 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -53,10 +53,7 @@ riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c -# Newer binutils versions default to ISA spec version 20191213 which moves some -# instructions from the I extension to the Zicsr and Zifencei extensions. -toolchain-need-zicsr-zifencei := $(call cc-option-yn, -march=$(riscv-march-y)_zicsr_zifencei) -riscv-march-$(toolchain-need-zicsr-zifencei) := $(riscv-march-y)_zicsr_zifencei +riscv-march-$(CONFIG_TOOLCHAIN_NEEDS_SPEC_20191213) := $(riscv-march-y)_zicsr_zifencei # Check if the toolchain supports Zicbom extension riscv-march-$(CONFIG_TOOLCHAIN_HAS_ZICBOM) := $(riscv-march-y)_zicbom -- 2.39.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig 2023-02-23 22:05 ` [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig Conor Dooley @ 2023-02-24 16:37 ` Nathan Chancellor 2023-02-24 17:00 ` Conor Dooley 0 siblings, 1 reply; 9+ messages in thread From: Nathan Chancellor @ 2023-02-24 16:37 UTC (permalink / raw) To: Conor Dooley; +Cc: palmer, Conor Dooley, naresh.kamboju, linux-riscv, llvm On Thu, Feb 23, 2023 at 10:05:45PM +0000, Conor Dooley wrote: > From: Conor Dooley <conor.dooley@microchip.com> > > Checking whether binutils defaults to using a version of the spec > requiring zicsr/zifencei being done in our Makefile is functionally > sufficient at present, but makes it harder to tell after the fact > which extensions are enabled. > By moving it to Kconfig, it's easy to tell from standard build artifacts > what has been done & the road is paved for dealing with this differently > for both binutils and LLVM. > > Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> > --- > arch/riscv/Kconfig | 10 ++++++++++ > arch/riscv/Makefile | 5 +---- > 2 files changed, 11 insertions(+), 4 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index cebf0c5f8824..4eb0ef8314b3 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -288,6 +288,16 @@ config ARCH_RV64I > > endchoice > > +config TOOLCHAIN_NEEDS_SPEC_20191213 This symbol's name is a little confusing to me, how does the toolchain need spec version 20191213. Maybe 'SPEC_20191213' should be something like 'EXPLICIT_ZICSR_ZIFENCEI'? Otherwise, maybe it should be something like 'TOOLCHAIN_HAS_DEFAULT_SPEC_20191213'? Sorry for the bikeshed but I think most Kconfig symbols should be self describing. > + bool > + default y > + depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicsr_zifencei) > + depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicsr_zifencei) > + help > + Newer binutils versions default to ISA spec version 20191213 which > + moves some instructions from the I extension to the Zicsr and Zifencei > + extensions. > + > # We must be able to map all physical memory into the kernel, but the compiler > # is still a bit more efficient when generating code if it's setup in a manner > # such that it can only map 2GiB of memory. > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile > index 12d91b0a73d8..7e1267b0e73f 100644 > --- a/arch/riscv/Makefile > +++ b/arch/riscv/Makefile > @@ -53,10 +53,7 @@ riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima > riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd > riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c > > -# Newer binutils versions default to ISA spec version 20191213 which moves some > -# instructions from the I extension to the Zicsr and Zifencei extensions. > -toolchain-need-zicsr-zifencei := $(call cc-option-yn, -march=$(riscv-march-y)_zicsr_zifencei) > -riscv-march-$(toolchain-need-zicsr-zifencei) := $(riscv-march-y)_zicsr_zifencei > +riscv-march-$(CONFIG_TOOLCHAIN_NEEDS_SPEC_20191213) := $(riscv-march-y)_zicsr_zifencei > > # Check if the toolchain supports Zicbom extension > riscv-march-$(CONFIG_TOOLCHAIN_HAS_ZICBOM) := $(riscv-march-y)_zicbom > -- > 2.39.1 > _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig 2023-02-24 16:37 ` Nathan Chancellor @ 2023-02-24 17:00 ` Conor Dooley 2023-03-06 23:52 ` Palmer Dabbelt 0 siblings, 1 reply; 9+ messages in thread From: Conor Dooley @ 2023-02-24 17:00 UTC (permalink / raw) To: Nathan Chancellor; +Cc: palmer, Conor Dooley, naresh.kamboju, linux-riscv, llvm [-- Attachment #1.1: Type: text/plain, Size: 1101 bytes --] On Fri, Feb 24, 2023 at 09:37:28AM -0700, Nathan Chancellor wrote: > On Thu, Feb 23, 2023 at 10:05:45PM +0000, Conor Dooley wrote: > > --- > > arch/riscv/Kconfig | 10 ++++++++++ > > arch/riscv/Makefile | 5 +---- > > 2 files changed, 11 insertions(+), 4 deletions(-) > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > index cebf0c5f8824..4eb0ef8314b3 100644 > > --- a/arch/riscv/Kconfig > > +++ b/arch/riscv/Kconfig > > @@ -288,6 +288,16 @@ config ARCH_RV64I > > > > endchoice > > > > +config TOOLCHAIN_NEEDS_SPEC_20191213 > > This symbol's name is a little confusing to me, how does the toolchain > need spec version 20191213. Maybe 'SPEC_20191213' should be something > like 'EXPLICIT_ZICSR_ZIFENCEI'? Otherwise, maybe it should be something > like 'TOOLCHAIN_HAS_DEFAULT_SPEC_20191213'? Sorry for the bikeshed but I > think most Kconfig symbols should be self describing. Yah I can do that. I actually had this as the DEFAULT_SPEC variant before and changed it - I'll switch it to the EXPLICIT one. Thanks for taking a look Nathan :) Conor. [-- Attachment #1.2: signature.asc --] [-- Type: application/pgp-signature, Size: 228 bytes --] [-- Attachment #2: Type: text/plain, Size: 161 bytes --] _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig 2023-02-24 17:00 ` Conor Dooley @ 2023-03-06 23:52 ` Palmer Dabbelt 2023-03-07 19:14 ` Conor Dooley 0 siblings, 1 reply; 9+ messages in thread From: Palmer Dabbelt @ 2023-03-06 23:52 UTC (permalink / raw) To: Conor Dooley; +Cc: nathan, Conor Dooley, naresh.kamboju, linux-riscv, llvm On Fri, 24 Feb 2023 09:00:09 PST (-0800), Conor Dooley wrote: > On Fri, Feb 24, 2023 at 09:37:28AM -0700, Nathan Chancellor wrote: >> On Thu, Feb 23, 2023 at 10:05:45PM +0000, Conor Dooley wrote: > >> > --- >> > arch/riscv/Kconfig | 10 ++++++++++ >> > arch/riscv/Makefile | 5 +---- >> > 2 files changed, 11 insertions(+), 4 deletions(-) >> > >> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig >> > index cebf0c5f8824..4eb0ef8314b3 100644 >> > --- a/arch/riscv/Kconfig >> > +++ b/arch/riscv/Kconfig >> > @@ -288,6 +288,16 @@ config ARCH_RV64I >> > >> > endchoice >> > >> > +config TOOLCHAIN_NEEDS_SPEC_20191213 >> >> This symbol's name is a little confusing to me, how does the toolchain >> need spec version 20191213. Maybe 'SPEC_20191213' should be something >> like 'EXPLICIT_ZICSR_ZIFENCEI'? Otherwise, maybe it should be something >> like 'TOOLCHAIN_HAS_DEFAULT_SPEC_20191213'? Sorry for the bikeshed but I >> think most Kconfig symbols should be self describing. > > Yah I can do that. I actually had this as the DEFAULT_SPEC variant > before and changed it - I'll switch it to the EXPLICIT one. > Thanks for taking a look Nathan :) Another option here would be to use the `-misa-spec` argument for GCC, to make it match LLVM's spec version. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig 2023-03-06 23:52 ` Palmer Dabbelt @ 2023-03-07 19:14 ` Conor Dooley 2023-03-07 19:24 ` Palmer Dabbelt 0 siblings, 1 reply; 9+ messages in thread From: Conor Dooley @ 2023-03-07 19:14 UTC (permalink / raw) To: Palmer Dabbelt; +Cc: nathan, Conor Dooley, naresh.kamboju, linux-riscv, llvm [-- Attachment #1.1: Type: text/plain, Size: 2090 bytes --] On Mon, Mar 06, 2023 at 03:52:27PM -0800, Palmer Dabbelt wrote: > On Fri, 24 Feb 2023 09:00:09 PST (-0800), Conor Dooley wrote: > > On Fri, Feb 24, 2023 at 09:37:28AM -0700, Nathan Chancellor wrote: > > > On Thu, Feb 23, 2023 at 10:05:45PM +0000, Conor Dooley wrote: > > > > > > --- > > > > arch/riscv/Kconfig | 10 ++++++++++ > > > > arch/riscv/Makefile | 5 +---- > > > > 2 files changed, 11 insertions(+), 4 deletions(-) > > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > > > index cebf0c5f8824..4eb0ef8314b3 100644 > > > > --- a/arch/riscv/Kconfig > > > > +++ b/arch/riscv/Kconfig > > > > @@ -288,6 +288,16 @@ config ARCH_RV64I > > > > > endchoice > > > > > +config TOOLCHAIN_NEEDS_SPEC_20191213 > > > > > > This symbol's name is a little confusing to me, how does the toolchain > > > need spec version 20191213. Maybe 'SPEC_20191213' should be something > > > like 'EXPLICIT_ZICSR_ZIFENCEI'? Otherwise, maybe it should be something > > > like 'TOOLCHAIN_HAS_DEFAULT_SPEC_20191213'? Sorry for the bikeshed but I > > > think most Kconfig symbols should be self describing. > > > > Yah I can do that. I actually had this as the DEFAULT_SPEC variant > > before and changed it - I'll switch it to the EXPLICIT one. > > Thanks for taking a look Nathan :) > > Another option here would be to use the `-misa-spec` argument for GCC, to > make it match LLVM's spec version. I'm not entirely sure what you're getting at. You're the toolchain guy, but my understanding was that gas and gcc have that option, but not ld, which rules out my initial interpretation. Are you suggesting that we always pass -misa-spec=<pre-zicsr_zifencei> to gcc so that we are using the same misa-spec for both gnu and llvm toolchain bits? My instinctive thought was that that is kinda fragile to things misaligning between gcc/llvm, but given I seem to end up looking at this every month, we're really fragile to changes in either camp anyway... I can go spin an alternative v2 of this up if I have understood you correctly. Thanks, Conor. [-- Attachment #1.2: signature.asc --] [-- Type: application/pgp-signature, Size: 228 bytes --] [-- Attachment #2: Type: text/plain, Size: 161 bytes --] _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig 2023-03-07 19:14 ` Conor Dooley @ 2023-03-07 19:24 ` Palmer Dabbelt 0 siblings, 0 replies; 9+ messages in thread From: Palmer Dabbelt @ 2023-03-07 19:24 UTC (permalink / raw) To: Conor Dooley; +Cc: nathan, Conor Dooley, naresh.kamboju, linux-riscv, llvm On Tue, 07 Mar 2023 11:14:54 PST (-0800), Conor Dooley wrote: > On Mon, Mar 06, 2023 at 03:52:27PM -0800, Palmer Dabbelt wrote: >> On Fri, 24 Feb 2023 09:00:09 PST (-0800), Conor Dooley wrote: >> > On Fri, Feb 24, 2023 at 09:37:28AM -0700, Nathan Chancellor wrote: >> > > On Thu, Feb 23, 2023 at 10:05:45PM +0000, Conor Dooley wrote: >> > >> > > > --- >> > > > arch/riscv/Kconfig | 10 ++++++++++ >> > > > arch/riscv/Makefile | 5 +---- >> > > > 2 files changed, 11 insertions(+), 4 deletions(-) >> > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig >> > > > index cebf0c5f8824..4eb0ef8314b3 100644 >> > > > --- a/arch/riscv/Kconfig >> > > > +++ b/arch/riscv/Kconfig >> > > > @@ -288,6 +288,16 @@ config ARCH_RV64I >> > > > > endchoice >> > > > > +config TOOLCHAIN_NEEDS_SPEC_20191213 >> > > >> > > This symbol's name is a little confusing to me, how does the toolchain >> > > need spec version 20191213. Maybe 'SPEC_20191213' should be something >> > > like 'EXPLICIT_ZICSR_ZIFENCEI'? Otherwise, maybe it should be something >> > > like 'TOOLCHAIN_HAS_DEFAULT_SPEC_20191213'? Sorry for the bikeshed but I >> > > think most Kconfig symbols should be self describing. >> > >> > Yah I can do that. I actually had this as the DEFAULT_SPEC variant >> > before and changed it - I'll switch it to the EXPLICIT one. >> > Thanks for taking a look Nathan :) >> >> Another option here would be to use the `-misa-spec` argument for GCC, to >> make it match LLVM's spec version. > > I'm not entirely sure what you're getting at. > You're the toolchain guy, but my understanding was that gas and gcc have > that option, but not ld, which rules out my initial interpretation. > Are you suggesting that we always pass -misa-spec=<pre-zicsr_zifencei> to > gcc so that we are using the same misa-spec for both gnu and llvm > toolchain bits? Pretty much, I think just $(cc-option -misa-spec=2.2) should do it. That should also cover older GCC versions, as we added the argument long before we changed the default. > My instinctive thought was that that is kinda fragile to things > misaligning between gcc/llvm, but given I seem to end up looking at this > every month, we're really fragile to changes in either camp anyway... Pretty much, but in this case we're essentially just disabling a form of change by sticking to an ISA spec version. > I can go spin an alternative v2 of this up if I have understood you > correctly. Thanks > > Thanks, > Conor. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v1 2/2] RISC-V: make TOOLCHAIN_NEEDS_SPEC_20191213 gas only 2023-02-23 22:05 [PATCH v1 0/2] RISC-V: avoid build issues for clang/llvm-17 with binutils 2.35 Conor Dooley 2023-02-23 22:05 ` [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig Conor Dooley @ 2023-02-23 22:05 ` Conor Dooley 2023-02-24 16:32 ` Nathan Chancellor 1 sibling, 1 reply; 9+ messages in thread From: Conor Dooley @ 2023-02-23 22:05 UTC (permalink / raw) To: palmer Cc: conor, Conor Dooley, nathan, naresh.kamboju, linux-riscv, llvm, stable From: Conor Dooley <conor.dooley@microchip.com> Quoting the llvm docs: > Between versions 2.0 and 2.1 of the base I specification, a backwards > incompatible change was made to remove selected instructions and CSRs > from the base ISA. These instructions were grouped into a set of new > extensions, but were no longer required by the base ISA. (snip) LLVM > currently implements version 2.0 of the base specification. Thus, > instructions from these extensions are accepted as part of the base > ISA. There is therefore no need (at present!) to carry out a $cc-option check, and instead just gate presence of zicsr and zifencei in march on the version of binutils that commit 6df2a016c0c8 ("riscv: fix build with binutils 2.38") highlights as the introduction of the requirement. In fact, the status quo creates some issues with mixed llvm/binutils builds, specifically building with llvm-17 and ld from binutils-2.35. Odd combo you may think, but this is what tuxsuite's debian stable uses while testing 5.10 stable kernels as doesn't support LLD. CC: stable@vger.kernel.org # needs RISC-V: move zicsr/zifencei spec version check to Kconfi Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Link: https://lore.kernel.org/all/CA+G9fYt9T=ELCLaB9byxaLW2Qf4pZcDO=huCA0D8ug2V2+irJQ@mail.gmail.com/ Suggested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> --- arch/riscv/Kconfig | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 4eb0ef8314b3..c6902f4c5650 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -291,8 +291,7 @@ endchoice config TOOLCHAIN_NEEDS_SPEC_20191213 bool default y - depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicsr_zifencei) - depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicsr_zifencei) + depends on AS_IS_GNU && AS_VERSION >= 23800 help Newer binutils versions default to ISA spec version 20191213 which moves some instructions from the I extension to the Zicsr and Zifencei -- 2.39.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH v1 2/2] RISC-V: make TOOLCHAIN_NEEDS_SPEC_20191213 gas only 2023-02-23 22:05 ` [PATCH v1 2/2] RISC-V: make TOOLCHAIN_NEEDS_SPEC_20191213 gas only Conor Dooley @ 2023-02-24 16:32 ` Nathan Chancellor 0 siblings, 0 replies; 9+ messages in thread From: Nathan Chancellor @ 2023-02-24 16:32 UTC (permalink / raw) To: Conor Dooley Cc: palmer, Conor Dooley, naresh.kamboju, linux-riscv, llvm, stable Hi Conor, On Thu, Feb 23, 2023 at 10:05:46PM +0000, Conor Dooley wrote: > From: Conor Dooley <conor.dooley@microchip.com> > > Quoting the llvm docs: > > Between versions 2.0 and 2.1 of the base I specification, a backwards > > incompatible change was made to remove selected instructions and CSRs > > from the base ISA. These instructions were grouped into a set of new > > extensions, but were no longer required by the base ISA. (snip) LLVM > > currently implements version 2.0 of the base specification. Thus, > > instructions from these extensions are accepted as part of the base > > ISA. > > There is therefore no need (at present!) to carry out a $cc-option > check, and instead just gate presence of zicsr and zifencei in march > on the version of binutils that commit 6df2a016c0c8 ("riscv: fix build > with binutils 2.38") highlights as the introduction of the requirement. > > In fact, the status quo creates some issues with mixed llvm/binutils > builds, specifically building with llvm-17 and ld from binutils-2.35. > Odd combo you may think, but this is what tuxsuite's debian stable uses > while testing 5.10 stable kernels as doesn't support LLD. > > CC: stable@vger.kernel.org # needs RISC-V: move zicsr/zifencei spec version check to Kconfi I think it would be better to drop this comment and just mark patch 1 for stable directly. However, if it remains, 'Kconfi' -> 'Kconfig' :) > Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> > Link: https://lore.kernel.org/all/CA+G9fYt9T=ELCLaB9byxaLW2Qf4pZcDO=huCA0D8ug2V2+irJQ@mail.gmail.com/ > Suggested-by: Nathan Chancellor <nathan@kernel.org> > Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Thanks for helping getting down to the bottom of this! > --- > arch/riscv/Kconfig | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 4eb0ef8314b3..c6902f4c5650 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -291,8 +291,7 @@ endchoice > config TOOLCHAIN_NEEDS_SPEC_20191213 > bool > default y > - depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicsr_zifencei) > - depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicsr_zifencei) > + depends on AS_IS_GNU && AS_VERSION >= 23800 > help > Newer binutils versions default to ISA spec version 20191213 which > moves some instructions from the I extension to the Zicsr and Zifencei > -- > 2.39.1 > _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2023-03-07 19:24 UTC | newest] Thread overview: 9+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2023-02-23 22:05 [PATCH v1 0/2] RISC-V: avoid build issues for clang/llvm-17 with binutils 2.35 Conor Dooley 2023-02-23 22:05 ` [PATCH v1 1/2] RISC-V: move zicsr/zifencei spec version check to Kconfig Conor Dooley 2023-02-24 16:37 ` Nathan Chancellor 2023-02-24 17:00 ` Conor Dooley 2023-03-06 23:52 ` Palmer Dabbelt 2023-03-07 19:14 ` Conor Dooley 2023-03-07 19:24 ` Palmer Dabbelt 2023-02-23 22:05 ` [PATCH v1 2/2] RISC-V: make TOOLCHAIN_NEEDS_SPEC_20191213 gas only Conor Dooley 2023-02-24 16:32 ` Nathan Chancellor
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