From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8883F2F549C; Wed, 4 Feb 2026 17:11:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770225082; cv=none; b=DrqewoBSOQUcIOkgtz5GUQDLXuSM36fnle7Oa1z6kdRF29n1rlNu/3MTn4FjQ3Q47SAKVvJITlT3Il8rTkDqCgWdwfhlQI9k5xEZZJw0VwPrmBf3ROrrIxLGmUevsoIOHxNJUgnUoMpHGj8ceAxw+OnhmY7VJOaj7FmyEAMKfiQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770225082; c=relaxed/simple; bh=DZr3xv+GzJNH7jtIzuWqZrotOseXwfU3NNhVN3urNoA=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=tYL0hVDfkamYtXR/nQKrkz6n5yS65DbtNl0hKsU0dKPZPwSuWWVlwkmPkxDfs06K9py4f9R5munXEiL4yEG3Ayu5I+8kA0nN0+Es16Fhkf7BGjPvNle6gCgSMxMJk3Fe8O0UvwEbY7rcvLy7WVRWe++8bdu8uj+Y+Sk/CTHIXH4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Eua5x8TM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Eua5x8TM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0968C116C6; Wed, 4 Feb 2026 17:11:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770225082; bh=DZr3xv+GzJNH7jtIzuWqZrotOseXwfU3NNhVN3urNoA=; h=Date:Subject:To:References:From:In-Reply-To:From; b=Eua5x8TMYdeA8rsjLKIAY7KFDuKGSosJKc9WzNWn/H3XEwUroNzMuRL9bkUMMsjrk Y+uHsZgcgMqS6Wm0LrIZ7EcC5qc7O7tXo30ui563EElDWqyapz64W/xhoC7CHc4hIr /rk1iVI/tlG0zPXRBn8X+Ez4BbdLGNJBpswbI+Z9Vg9nwOXpkCa49MjsrEQdum8P5G 2tjYO2p9LglFje12n7lVze6IgrPbMDGpgsJ/oeCWI6GNt/KioZncq1PBnQ5NSTIFls J3tz1UpJ1MNxlJ1ENLB/+6dhZSGBhZ/eELez8eNmtKpgFwmFuff5o9YOPrwR67jxdN FFA2w5wr42DXA== Message-ID: Date: Wed, 4 Feb 2026 18:11:13 +0100 Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] powerpc: Enable Rust for ppc64le To: "Mukesh Kumar Chaurasiya (IBM)" , maddy@linux.ibm.com, mpe@ellerman.id.au, npiggin@gmail.com, peterz@infradead.org, jpoimboe@kernel.org, jbaron@akamai.com, rostedt@goodmis.org, ardb@kernel.org, ojeda@kernel.org, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, lossin@kernel.org, a.hindborg@kernel.org, aliceryhl@google.com, tmgross@umich.edu, dakr@kernel.org, nathan@kernel.org, nick.desaulniers+lkml@gmail.com, morbo@google.com, justinstitt@google.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, llvm@lists.linux.dev, Link Mauve References: <20260204042417.83903-1-mkchauras@gmail.com> Content-Language: fr-FR From: "Christophe Leroy (CS GROUP)" In-Reply-To: <20260204042417.83903-1-mkchauras@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi Mukesh, hi Link, Le 04/02/2026 à 05:24, Mukesh Kumar Chaurasiya (IBM) a écrit : > [Vous ne recevez pas souvent de courriers de mkchauras@gmail.com. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ] > > Enabling rust support for ppc64 only. Link Mauve has sent a patch for rust support on PPC32 a few hours before you, see https://lore.kernel.org/r/20260204030507.8203-1-linkmauve@linkmauve.fr Could you coordinate together to provide something supporting both PPC32 and PPC64 ? I see the following conflicts at the time being. I also have a few comments down. diff --git a/Documentation/rust/arch-support.rst b/Documentation/rust/arch-support.rst index 6e6a515d0899..70b9e192a7a0 100644 --- a/Documentation/rust/arch-support.rst +++ b/Documentation/rust/arch-support.rst @@ -18,6 +18,7 @@ Architecture Level of support Constraints ``arm`` Maintained ARMv7 Little Endian only. ``arm64`` Maintained Little Endian only. ``loongarch`` Maintained \- +``powerpc`` Maintained 32-bit Big Endian only. ``riscv`` Maintained ``riscv64`` and LLVM/Clang only. ``um`` Maintained \- ``x86`` Maintained ``x86_64`` only. diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index b8d36a261009..80b2666fc5af 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -283,8 +283,10 @@ config PPC select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RELIABLE_STACKTRACE select HAVE_RSEQ + select HAVE_RUST if PPC32 select HAVE_SAMPLE_FTRACE_DIRECT if HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_SAMPLE_FTRACE_DIRECT_MULTI if HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + select HAVE_RUST if PPC64 select HAVE_SETUP_PER_CPU_AREA if PPC64 select HAVE_SOFTIRQ_ON_OWN_STACK select HAVE_STACKPROTECTOR if PPC32 && $(cc-option,$(m32-flag) -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=0) diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index a58b1029592c..ac6fe8cc4ece 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -61,6 +61,8 @@ else KBUILD_LDFLAGS_MODULE += $(objtree)/arch/powerpc/lib/crtsavres.o endif +KBUILD_RUSTFLAGS += --target=powerpc-unknown-linux-gnu + ifdef CONFIG_CPU_LITTLE_ENDIAN KBUILD_CPPFLAGS += -mlittle-endian KBUILD_LDFLAGS += -EL @@ -172,10 +174,11 @@ CFLAGS-y += $(CONFIG_TUNE_CPU) asinstr := $(call as-instr,lis 9$(comma)foo@high,-DHAVE_AS_ATHIGH=1) -KBUILD_CPPFLAGS += -I $(srctree)/arch/powerpc $(asinstr) -KBUILD_AFLAGS += $(AFLAGS-y) -KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU) -KBUILD_CFLAGS += $(CFLAGS-y) +KBUILD_CPPFLAGS += -I $(srctree)/arch/powerpc $(asinstr) +KBUILD_AFLAGS += $(AFLAGS-y) +KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU) +KBUILD_CFLAGS += $(CFLAGS-y) +KBUILD_RUSTFLAGS += -Ctarget-feature=-mma,-vsx,-hard-float,-altivec CHECKFLAGS += -m$(BITS) -D__powerpc__ -D__powerpc$(BITS)__ ifdef CONFIG_CPU_BIG_ENDIAN diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/asm/jump_label.h index d4eaba459a0e..d2284c72d21b 100644 --- a/arch/powerpc/include/asm/jump_label.h +++ b/arch/powerpc/include/asm/jump_label.h @@ -15,14 +15,35 @@ #define JUMP_ENTRY_TYPE stringify_in_c(FTR_ENTRY_LONG) #define JUMP_LABEL_NOP_SIZE 4 +<<<<<<< HEAD +/* This macro is also expanded on the Rust side. */ +#define ARCH_STATIC_BRANCH_ASM(key, label) \ + "1:\n\t" \ + "nop # arch_static_branch\n\t" \ + ".pushsection __jump_table, \"aw\"\n\t" \ + ".long 1b - ., " label " - .\n\t" \ + JUMP_ENTRY_TYPE key " - .\n\t" \ + ".popsection \n\t" + static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { - asm goto("1:\n\t" - "nop # arch_static_branch\n\t" - ".pushsection __jump_table, \"aw\"\n\t" - ".long 1b - ., %l[l_yes] - .\n\t" - JUMP_ENTRY_TYPE "%c0 - .\n\t" - ".popsection \n\t" + asm goto(ARCH_STATIC_BRANCH_ASM("%c0", "%l[l_yes]") +======= +#define JUMP_TABLE_ENTRY(key, label) \ + ".pushsection __jump_table, \"aw\" \n\t" \ + ".long 1b - ., " label " - . \n\t" \ + JUMP_ENTRY_TYPE key " - . \n\t" \ + ".popsection \n\t" + +#define ARCH_STATIC_BRANCH_ASM(key, label) \ + "1: nop \n\t" \ + JUMP_TABLE_ENTRY(key,label) + +static __always_inline bool arch_static_branch(struct static_key *key, bool branch) +{ + asm goto( + ARCH_STATIC_BRANCH_ASM("%c0", "%l[l_yes]") +>>>>>>> rust64 : : "i" (&((char *)key)[branch]) : : l_yes); return false; @@ -34,10 +55,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool { asm goto("1:\n\t" "b %l[l_yes] # arch_static_branch_jump\n\t" - ".pushsection __jump_table, \"aw\"\n\t" - ".long 1b - ., %l[l_yes] - .\n\t" - JUMP_ENTRY_TYPE "%c0 - .\n\t" - ".popsection \n\t" + JUMP_TABLE_ENTRY("%c0", "%l[l_yes]") : : "i" (&((char *)key)[branch]) : : l_yes); return false; diff --git a/rust/Makefile b/rust/Makefile index 5d357dce1704..9b72c1e96191 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -383,13 +383,19 @@ bindgen_skip_c_flags := -mno-fp-ret-in-387 -mpreferred-stack-boundary=% \ -fno-inline-functions-called-once -fsanitize=bounds-strict \ -fstrict-flex-arrays=% -fmin-function-alignment=% \ -fzero-init-padding-bits=% -mno-fdpic \ - --param=% --param asan-% -fno-isolate-erroneous-paths-dereference + --param=% --param asan-% -fno-isolate-erroneous-paths-dereference \ + -ffixed-r2 -mmultiple -mno-readonly-in-sdata # Derived from `scripts/Makefile.clang`. BINDGEN_TARGET_x86 := x86_64-linux-gnu BINDGEN_TARGET_arm64 := aarch64-linux-gnu BINDGEN_TARGET_arm := arm-linux-gnueabi BINDGEN_TARGET_loongarch := loongarch64-linux-gnusf +<<<<<<< HEAD +BINDGEN_TARGET_powerpc := powerpc-linux-gnu +======= +BINDGEN_TARGET_powerpc := powerpc64le-linux-gnu +>>>>>>> rust64 BINDGEN_TARGET_um := $(BINDGEN_TARGET_$(SUBARCH)) BINDGEN_TARGET := $(BINDGEN_TARGET_$(SRCARCH)) diff --git a/scripts/generate_rust_target.rs b/scripts/generate_rust_target.rs index 38b3416bb979..1860af50b926 100644 --- a/scripts/generate_rust_target.rs +++ b/scripts/generate_rust_target.rs @@ -188,6 +188,16 @@ fn main() { panic!("arm uses the builtin rustc target"); } else if cfg.has("ARM64") { panic!("arm64 uses the builtin rustc aarch64-unknown-none target"); + } else if cfg.has("PPC32") { + ts.push("arch", "powerpc"); + ts.push("data-layout", "E-m:e-p:32:32-Fn32-i64:64-n32"); + ts.push("features", "+soft-float"); + ts.push("llvm-target", "powerpc-unknown-eabi"); + if cfg.rustc_version_atleast(1, 91, 0) { + ts.push("target-pointer-width", 32); + } else { + ts.push("target-pointer-width", "32"); + } } else if cfg.has("RISCV") { if cfg.has("64BIT") { panic!("64-bit RISC-V uses the builtin rustc riscv64-unknown-none-elf target"); @@ -256,6 +266,30 @@ fn main() { } } else if cfg.has("LOONGARCH") { panic!("loongarch uses the builtin rustc loongarch64-unknown-none-softfloat target"); + } else if cfg.has("PPC64") { + ts.push("arch", "powerpc64"); + ts.push( + "data-layout", + if cfg.has("CPU_LITTLE_ENDIAN") { + "e-m:e-Fn32-i64:64-n32:64-S128-v256:256:256-v512:512:512" + } else { + "E-m:e-Fn32-i64:64-n32:64-S128-v256:256:256-v512:512:512" + }, + ); + ts.push("features", "-mma,-altivec,-vsx,-hard-float"); + ts.push( + "llvm-target", + if cfg.has("CPU_LITTLE_ENDIAN") { + "powerpc64le-linux-gnu" + } else { + "powerpc64-linux-gnu" + }, + ); + if cfg.rustc_version_atleast(1, 91, 0) { + ts.push("target-pointer-width", 64); + } else { + ts.push("target-pointer-width", "64"); + } } else { panic!("Unsupported architecture"); } [...] > --- > arch/powerpc/Kconfig | 1 + > arch/powerpc/Makefile | 9 +++++---- > arch/powerpc/include/asm/jump_label.h | 23 +++++++++++++---------- > rust/Makefile | 1 + > scripts/generate_rust_target.rs | 24 ++++++++++++++++++++++++ > 5 files changed, 44 insertions(+), 14 deletions(-) > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 9537a61ebae0..e9b8d761ed52 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -285,6 +285,7 @@ config PPC > select HAVE_RSEQ > select HAVE_SAMPLE_FTRACE_DIRECT if HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS > select HAVE_SAMPLE_FTRACE_DIRECT_MULTI if HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS > + select HAVE_RUST if PPC64 Keep in alphabetic order > select HAVE_SETUP_PER_CPU_AREA if PPC64 > select HAVE_SOFTIRQ_ON_OWN_STACK > select HAVE_STACKPROTECTOR if PPC32 && $(cc-option,$(m32-flag) -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=0) > diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile > index a58b1029592c..7ad28cf0fd35 100644 > --- a/arch/powerpc/Makefile > +++ b/arch/powerpc/Makefile > @@ -172,10 +172,11 @@ CFLAGS-y += $(CONFIG_TUNE_CPU) > > asinstr := $(call as-instr,lis 9$(comma)foo@high,-DHAVE_AS_ATHIGH=1) > > -KBUILD_CPPFLAGS += -I $(srctree)/arch/powerpc $(asinstr) > -KBUILD_AFLAGS += $(AFLAGS-y) > -KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU) > -KBUILD_CFLAGS += $(CFLAGS-y) > +KBUILD_CPPFLAGS += -I $(srctree)/arch/powerpc $(asinstr) > +KBUILD_AFLAGS += $(AFLAGS-y) > +KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU) > +KBUILD_CFLAGS += $(CFLAGS-y) > +KBUILD_RUSTFLAGS += -Ctarget-feature=-mma,-vsx,-hard-float,-altivec > > CHECKFLAGS += -m$(BITS) -D__powerpc__ -D__powerpc$(BITS)__ > ifdef CONFIG_CPU_BIG_ENDIAN > diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/asm/jump_label.h > index d4eaba459a0e..a6b211502bfe 100644 > --- a/arch/powerpc/include/asm/jump_label.h > +++ b/arch/powerpc/include/asm/jump_label.h > @@ -15,14 +15,20 @@ > #define JUMP_ENTRY_TYPE stringify_in_c(FTR_ENTRY_LONG) > #define JUMP_LABEL_NOP_SIZE 4 > > +#define JUMP_TABLE_ENTRY(key, label) \ > + ".pushsection __jump_table, \"aw\" \n\t" \ > + ".long 1b - ., " label " - . \n\t" \ > + JUMP_ENTRY_TYPE key " - . \n\t" \ > + ".popsection \n\t" > + > +#define ARCH_STATIC_BRANCH_ASM(key, label) \ > + "1: nop \n\t" \ > + JUMP_TABLE_ENTRY(key,label) > + > static __always_inline bool arch_static_branch(struct static_key *key, bool branch) > { > - asm goto("1:\n\t" > - "nop # arch_static_branch\n\t" > - ".pushsection __jump_table, \"aw\"\n\t" > - ".long 1b - ., %l[l_yes] - .\n\t" > - JUMP_ENTRY_TYPE "%c0 - .\n\t" > - ".popsection \n\t" > + asm goto( > + ARCH_STATIC_BRANCH_ASM("%c0", "%l[l_yes]") > : : "i" (&((char *)key)[branch]) : : l_yes); > > return false; > @@ -34,10 +40,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool > { > asm goto("1:\n\t" > "b %l[l_yes] # arch_static_branch_jump\n\t" > - ".pushsection __jump_table, \"aw\"\n\t" > - ".long 1b - ., %l[l_yes] - .\n\t" > - JUMP_ENTRY_TYPE "%c0 - .\n\t" > - ".popsection \n\t" > + JUMP_TABLE_ENTRY("%c0", "%l[l_yes]") > : : "i" (&((char *)key)[branch]) : : l_yes); > > return false; > diff --git a/rust/Makefile b/rust/Makefile > index 5d357dce1704..7a6daa822cbc 100644 > --- a/rust/Makefile > +++ b/rust/Makefile > @@ -390,6 +390,7 @@ BINDGEN_TARGET_x86 := x86_64-linux-gnu > BINDGEN_TARGET_arm64 := aarch64-linux-gnu > BINDGEN_TARGET_arm := arm-linux-gnueabi > BINDGEN_TARGET_loongarch := loongarch64-linux-gnusf > +BINDGEN_TARGET_powerpc := powerpc64le-linux-gnu This needs to depend on CONFIG_PPC64 and CONFIG_CPU_LITTLE_ENDIAN. > BINDGEN_TARGET_um := $(BINDGEN_TARGET_$(SUBARCH)) > BINDGEN_TARGET := $(BINDGEN_TARGET_$(SRCARCH)) > > diff --git a/scripts/generate_rust_target.rs b/scripts/generate_rust_target.rs > index 38b3416bb979..875579b37424 100644 > --- a/scripts/generate_rust_target.rs > +++ b/scripts/generate_rust_target.rs > @@ -256,6 +256,30 @@ fn main() { > } > } else if cfg.has("LOONGARCH") { > panic!("loongarch uses the builtin rustc loongarch64-unknown-none-softfloat target"); > + } else if cfg.has("PPC64") { Shouldn't this be done closer to PPC32 ? > + ts.push("arch", "powerpc64"); > + ts.push( > + "data-layout", > + if cfg.has("CPU_LITTLE_ENDIAN") { > + "e-m:e-Fn32-i64:64-n32:64-S128-v256:256:256-v512:512:512" > + } else { > + "E-m:e-Fn32-i64:64-n32:64-S128-v256:256:256-v512:512:512" > + }, > + ); > + ts.push("features", "-mma,-altivec,-vsx,-hard-float"); > + ts.push( > + "llvm-target", > + if cfg.has("CPU_LITTLE_ENDIAN") { > + "powerpc64le-linux-gnu" > + } else { > + "powerpc64-linux-gnu" > + }, > + ); > + if cfg.rustc_version_atleast(1, 91, 0) { > + ts.push("target-pointer-width", 64); > + } else { > + ts.push("target-pointer-width", "64"); > + } > } else { > panic!("Unsupported architecture"); > } > -- > 2.52.0 >