kernel/linux.git/arch/riscv/include/uapi/asm, branch v6.1.174

asm-generic: partially revert "Unify uapi bitsperlong.h for arm64, riscv and loongarch"

2025-12-06T21:12:36+00:00

commit 6e8d96909a23c8078ee965bd48bb31cbef2de943 upstream. Unifying the asm-generic headers across 32-bit and 64-bit architectures based on the compiler provided macros was a good idea and appears to work with all user space, but it caused a regression when building old kernels on systems that have the new headers installed in /usr/include, as this combination trips an inconsistency in the kernel's own tools/include headers that are a mix of userspace and kernel-internal headers. This affects kernel builds on arm64, riscv64 and loongarch64 systems that might end up using the "#define __BITS_PER_LONG 32" default from the old tools headers. Backporting the commit into stable kernels would address this, but it would still break building kernels without that backport, and waste time for developers trying to understand the problem. arm64 build machines are rather common, and on riscv64 this can also happen in practice, but loongarch64 is probably new enough to not be used much for building old kernels, so only revert the bits for arm64 and riscv. Link: https://lore.kernel.org/all/20230731160402.GB1823389@dev-arch.thelio-3990X/ Reported-by: Nathan Chancellor Fixes: 8386f58f8deda ("asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch") Acked-by: Catalin Marinas Acked-by: Palmer Dabbelt Tested-by: Nathan Chancellor Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman

asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch

2025-12-06T21:12:34+00:00

[ Upstream commit 8386f58f8deda81110283798a387fb53ec21957c ] Now we specify the minimal version of GCC as 5.1 and Clang/LLVM as 11.0.0 in Documentation/process/changes.rst, __CHAR_BIT__ and __SIZEOF_LONG__ are usable, it is probably fine to unify the definition of __BITS_PER_LONG as (__CHAR_BIT__ * __SIZEOF_LONG__) in asm-generic uapi bitsperlong.h. In order to keep safe and avoid regression, only unify uapi bitsperlong.h for some archs such as arm64, riscv and loongarch which are using newer toolchains that have the definitions of __CHAR_BIT__ and __SIZEOF_LONG__. Suggested-by: Xi Ruoyao Link: https://lore.kernel.org/all/d3e255e4746de44c9903c4433616d44ffcf18d1b.camel@xry111.site/ Suggested-by: Arnd Bergmann Link: https://lore.kernel.org/linux-arch/a3a4f48a-07d4-4ed9-bc53-5d383428bdd2@app.fastmail.com/ Signed-off-by: Tiezhu Yang Signed-off-by: Arnd Bergmann Signed-off-by: Sasha Levin

riscv: Bump COMMAND_LINE_SIZE value to 1024

2023-03-30T10:49:16+00:00

[ Upstream commit 61fc1ee8be26bc192d691932b0a67eabee45d12f ] Increase COMMAND_LINE_SIZE as the current default value is too low for syzbot kernel command line. There has been considerable discussion on this patch that has led to a larger patch set removing COMMAND_LINE_SIZE from the uapi headers on all ports. That's not quite done yet, but it's gotten far enough we're confident this is not a uABI change so this is safe. Reported-by: Dmitry Vyukov Signed-off-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20210316193420.904-1-alex@ghiti.fr [Palmer: it's not uabi] Link: https://lore.kernel.org/linux-riscv/874b8076-b0d1-4aaa-bcd8-05d523060152@app.fastmail.com/#t Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

Merge tag 'riscv-for-linus-6.1-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

2022-10-14T18:21:11+00:00

Pull more RISC-V updates from Palmer Dabbelt: - DT updates for the PolarFire SOC - a fix to correct the handling of write-only mappings - m{vetndor,arcd,imp}id is now in /proc/cpuinfo - the SiFive L2 cache controller support has been refactored to also support L3 caches - misc fixes, cleanups and improvements throughout the tree * tag 'riscv-for-linus-6.1-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (42 commits) MAINTAINERS: add RISC-V's patchwork RISC-V: Make port I/O string accessors actually work riscv: enable software resend of irqs RISC-V: Re-enable counter access from userspace riscv: vdso: fix NULL deference in vdso_join_timens() when vfork riscv: Add cache information in AUX vector soc: sifive: ccache: define the macro for the register shifts soc: sifive: ccache: use pr_fmt() to remove CCACHE: prefixes soc: sifive: ccache: reduce printing on init soc: sifive: ccache: determine the cache level from dts soc: sifive: ccache: Rename SiFive L2 cache to Composable cache. dt-bindings: sifive-ccache: change Sifive L2 cache to Composable cache riscv: check for kernel config option in t-head memory types errata riscv: use BIT() marco for cpufeature probing riscv: use BIT() macros in t-head errata init riscv: drop some idefs from CMO initialization riscv: cleanup svpbmt cpufeature probing riscv: Pass -mno-relax only on lld < 15.0.0 RISC-V: Avoid dereferening NULL regs in die() dt-bindings: riscv: add new riscv,isa strings for emulators ...

riscv: Add cache information in AUX vector

2022-10-13T18:06:56+00:00

There are no standard CSR registers to provide cache information, the way for RISC-V is to get this information from DT. sysconf syscall could use them to get information of cache through AUX vector. The result of 'getconf -a|grep -i cache' as follows: LEVEL1_ICACHE_SIZE 32768 LEVEL1_ICACHE_ASSOC 2 LEVEL1_ICACHE_LINESIZE 64 LEVEL1_DCACHE_SIZE 32768 LEVEL1_DCACHE_ASSOC 4 LEVEL1_DCACHE_LINESIZE 64 LEVEL2_CACHE_SIZE 524288 LEVEL2_CACHE_ASSOC 8 LEVEL2_CACHE_LINESIZE 64 LEVEL3_CACHE_SIZE 4194304 LEVEL3_CACHE_ASSOC 16 LEVEL3_CACHE_LINESIZE 64 LEVEL4_CACHE_SIZE 0 LEVEL4_CACHE_ASSOC 0 LEVEL4_CACHE_LINESIZE 0 Signed-off-by: Greentime Hu Signed-off-by: Zong Li Suggested-by: Zong Li Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20220913061817.22564-8-zong.li@sifive.com Signed-off-by: Palmer Dabbelt

RISC-V: KVM: Expose Zicbom to the guest

2022-10-02T04:49:05+00:00

Guests may use the cbo.inval,clean,flush instructions when the CPU has the Zicbom extension and the hypervisor sets henvcfg.CBIE (for cbo.inval) and henvcfg.CBCFE (for cbo.clean,flush). Add Zicbom support for KVM guests which may be enabled and disabled from KVM userspace using the ISA extension ONE_REG API. Also opportunistically switch the other isa extension checks in kvm_riscv_vcpu_update_config() to riscv_isa_extension_available(). Signed-off-by: Andrew Jones Reviewed-by: Conor Dooley Reviewed-by: Atish Patra Signed-off-by: Anup Patel

RISC-V: KVM: Provide UAPI for Zicbom block size

2022-10-02T04:48:59+00:00

We're about to allow guests to use the Zicbom extension. KVM userspace needs to know the cache block size in order to properly advertise it to the guest. Provide a virtual config register for userspace to get it with the GET_ONE_REG API, but setting it cannot be supported, so disallow SET_ONE_REG. Signed-off-by: Andrew Jones Reviewed-by: Conor Dooley Reviewed-by: Atish Patra Signed-off-by: Anup Patel

RISC-V: KVM: Allow Guest use Zihintpause extension

2022-10-02T04:48:48+00:00

We should advertise Zihintpause ISA extension to KVM user-space whenever host supports it. This will allow KVM user-space (i.e. QEMU or KVMTOOL) to pass on this information to Guest via ISA string. Signed-off-by: Mayuresh Chitale Reviewed-by: Andrew Jones Signed-off-by: Anup Patel

RISC-V: KVM: Allow Guest use Svinval extension

2022-10-02T04:48:42+00:00

We should advertise Svinval ISA extension to KVM user-space whenever host supports it. This will allow KVM user-space (i.e. QEMU or KVMTOOL) to pass on this information to Guest via ISA string. Signed-off-by: Anup Patel Reviewed-by: Andrew Jones Signed-off-by: Anup Patel

RISC-V: KVM: Support sstc extension

2022-08-12T14:43:57+00:00

Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel Signed-off-by: Atish Patra Acked-by: Anup Patel Link: https://lore.kernel.org/all/CAAhSdy2mb6wyqy0NAn9BcTWKMYEc0Z4zU3s3j7oNqBz6eDQ9sg@mail.gmail.com/ Signed-off-by: Palmer Dabbelt