Hey Andy, On Fri, Feb 24, 2023 at 05:01:09PM +0000, Andy Chiu wrote: > Vector unit is disabled by default for all user processes. Thus, a > process will take a trap (illegal instruction) into kernel at the first > time when it uses Vector. Only after then, the kernel allocates V > context and starts take care of the context for that user process. > > Suggested-by: Richard Henderson <richard.henderson@xxxxxxxxxx> > Link: https://lore.kernel.org/r/3923eeee-e4dc-0911-40bf-84c34aee962d@xxxxxxxxxx > Signed-off-by: Andy Chiu <andy.chiu@xxxxxxxxxx> > --- > diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c > index 082baf2a061f..585e2c51b28e 100644 > --- a/arch/riscv/kernel/vector.c > +++ b/arch/riscv/kernel/vector.c > @@ -4,9 +4,19 @@ > * Author: Andy Chiu <andy.chiu@xxxxxxxxxx> > */ > #include <linux/export.h> > +#include <linux/sched/signal.h> > +#include <linux/types.h> > +#include <linux/slab.h> > +#include <linux/sched.h> > +#include <linux/uaccess.h> > > +#include <asm/thread_info.h> > +#include <asm/processor.h> > +#include <asm/insn.h> > #include <asm/vector.h> > #include <asm/csr.h> > +#include <asm/ptrace.h> > +#include <asm/bug.h> > > unsigned long riscv_v_vsize __read_mostly; > EXPORT_SYMBOL_GPL(riscv_v_vsize); > @@ -19,3 +29,84 @@ void riscv_v_setup_vsize(void) > riscv_v_disable(); > } > > +static bool insn_is_vector(u32 insn_buf) > +{ > + u32 opcode = insn_buf & __INSN_OPCODE_MASK; > + bool is_vector = false; > + > + /* > + * All V-related instructions, including CSR operations are 4-Byte. So, > + * do not handle if the instruction length is not 4-Byte. > + */ > + if (unlikely(GET_INSN_LENGTH(insn_buf) != 4)) > + return false; > + > + switch (opcode) { > + case RVV_OPCODE_VECTOR: > + is_vector = true; > + break; > + case RVV_OPCODE_VL: > + case RVV_OPCODE_VS: > + u32 width = RVV_EXRACT_VL_VS_WIDTH(insn_buf); > + > + if (width == RVV_VL_VS_WIDTH_8 || width == RVV_VL_VS_WIDTH_16 || > + width == RVV_VL_VS_WIDTH_32 || width == RVV_VL_VS_WIDTH_64) > + is_vector = true; > + break; > + case RVG_OPCODE_SYSTEM: > + u32 csr = RVG_EXTRACT_SYSTEM_CSR(insn_buf); > + > + if ((csr >= CSR_VSTART && csr <= CSR_VCSR) || > + (csr >= CSR_VL && csr <= CSR_VLENB)) > + is_vector = true; > + break; > + } Unfortunately, this is not valid code: /stuff/linux/arch/riscv/kernel/vector.c:50:3: error: expected expression u32 width = RVV_EXRACT_VL_VS_WIDTH(insn_buf); ^ /stuff/linux/arch/riscv/kernel/vector.c:52:7: error: use of undeclared identifier 'width' if (width == RVV_VL_VS_WIDTH_8 || width == RVV_VL_VS_WIDTH_16 || ^ /stuff/linux/arch/riscv/kernel/vector.c:52:37: error: use of undeclared identifier 'width' if (width == RVV_VL_VS_WIDTH_8 || width == RVV_VL_VS_WIDTH_16 || ^ /stuff/linux/arch/riscv/kernel/vector.c:53:7: error: use of undeclared identifier 'width' width == RVV_VL_VS_WIDTH_32 || width == RVV_VL_VS_WIDTH_64) ^ /stuff/linux/arch/riscv/kernel/vector.c:53:38: error: use of undeclared identifier 'width' width == RVV_VL_VS_WIDTH_32 || width == RVV_VL_VS_WIDTH_64) ^ /stuff/linux/arch/riscv/kernel/vector.c:57:3: error: expected expression u32 csr = RVG_EXTRACT_SYSTEM_CSR(insn_buf); ^ /stuff/linux/arch/riscv/kernel/vector.c:59:8: error: use of undeclared identifier 'csr' if ((csr >= CSR_VSTART && csr <= CSR_VCSR) || ^ /stuff/linux/arch/riscv/kernel/vector.c:59:29: error: use of undeclared identifier 'csr' if ((csr >= CSR_VSTART && csr <= CSR_VCSR) || ^ /stuff/linux/arch/riscv/kernel/vector.c:60:8: error: use of undeclared identifier 'csr' (csr >= CSR_VL && csr <= CSR_VLENB)) ^ /stuff/linux/arch/riscv/kernel/vector.c:60:25: error: use of undeclared identifier 'csr' (csr >= CSR_VL && csr <= CSR_VLENB)) ^ 10 errors generated. make[5]: *** [/stuff/linux/scripts/Makefile.build:252: arch/riscv/kernel/vector.o] Error 1 :/
Attachment:
signature.asc
Description: PGP signature
