6.5-stable review patch. If anyone has any objections, please let me know.
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From: Andy Chiu andy.chiu@sifive.com
commit 9300f00439743c4a34d735e1a27118eb68a1504e upstream.
This patch add back the ptrace support with the following fix: - Define NT_RISCV_CSR and re-number NT_RISCV_VECTOR to prevent conflicting with gdb's NT_RISCV_CSR. - Use struct __riscv_v_regset_state to handle ptrace requests
Since gdb does not directly include the note description header in Linux and has already defined NT_RISCV_CSR as 0x900, we decide to sync with gdb and renumber NT_RISCV_VECTOR to solve and prevent future conflicts.
Fixes: 0c59922c769a ("riscv: Add ptrace vector support") Signed-off-by: Andy Chiu andy.chiu@sifive.com Link: https://lore.kernel.org/r/20230825050248.32681-1-andy.chiu@sifive.com [Palmer: Drop the unused "size" variable in riscv_vr_set().] Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/riscv/include/uapi/asm/ptrace.h | 13 +++-- arch/riscv/kernel/ptrace.c | 79 ++++++++++++++++++++++++++++ include/uapi/linux/elf.h | 2 + 3 files changed, 90 insertions(+), 4 deletions(-)
diff --git a/arch/riscv/include/uapi/asm/ptrace.h b/arch/riscv/include/uapi/asm/ptrace.h index 283800130614..575e95bb1bc3 100644 --- a/arch/riscv/include/uapi/asm/ptrace.h +++ b/arch/riscv/include/uapi/asm/ptrace.h @@ -103,13 +103,18 @@ struct __riscv_v_ext_state { * In signal handler, datap will be set a correct user stack offset * and vector registers will be copied to the address of datap * pointer. - * - * In ptrace syscall, datap will be set to zero and the vector - * registers will be copied to the address right after this - * structure. */ };
+struct __riscv_v_regset_state { + unsigned long vstart; + unsigned long vl; + unsigned long vtype; + unsigned long vcsr; + unsigned long vlenb; + char vreg[]; +}; + /* * According to spec: The number of bits in a single vector register, * VLEN >= ELEN, which must be a power of 2, and must be no greater than diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 487303e3ef22..2afe460de16a 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -25,6 +25,9 @@ enum riscv_regset { #ifdef CONFIG_FPU REGSET_F, #endif +#ifdef CONFIG_RISCV_ISA_V + REGSET_V, +#endif };
static int riscv_gpr_get(struct task_struct *target, @@ -81,6 +84,71 @@ static int riscv_fpr_set(struct task_struct *target, } #endif
+#ifdef CONFIG_RISCV_ISA_V +static int riscv_vr_get(struct task_struct *target, + const struct user_regset *regset, + struct membuf to) +{ + struct __riscv_v_ext_state *vstate = &target->thread.vstate; + struct __riscv_v_regset_state ptrace_vstate; + + if (!riscv_v_vstate_query(task_pt_regs(target))) + return -EINVAL; + + /* + * Ensure the vector registers have been saved to the memory before + * copying them to membuf. + */ + if (target == current) + riscv_v_vstate_save(current, task_pt_regs(current)); + + ptrace_vstate.vstart = vstate->vstart; + ptrace_vstate.vl = vstate->vl; + ptrace_vstate.vtype = vstate->vtype; + ptrace_vstate.vcsr = vstate->vcsr; + ptrace_vstate.vlenb = vstate->vlenb; + + /* Copy vector header from vstate. */ + membuf_write(&to, &ptrace_vstate, sizeof(struct __riscv_v_regset_state)); + + /* Copy all the vector registers from vstate. */ + return membuf_write(&to, vstate->datap, riscv_v_vsize); +} + +static int riscv_vr_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + struct __riscv_v_ext_state *vstate = &target->thread.vstate; + struct __riscv_v_regset_state ptrace_vstate; + + if (!riscv_v_vstate_query(task_pt_regs(target))) + return -EINVAL; + + /* Copy rest of the vstate except datap */ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ptrace_vstate, 0, + sizeof(struct __riscv_v_regset_state)); + if (unlikely(ret)) + return ret; + + if (vstate->vlenb != ptrace_vstate.vlenb) + return -EINVAL; + + vstate->vstart = ptrace_vstate.vstart; + vstate->vl = ptrace_vstate.vl; + vstate->vtype = ptrace_vstate.vtype; + vstate->vcsr = ptrace_vstate.vcsr; + + /* Copy all the vector registers. */ + pos = 0; + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate->datap, + 0, riscv_v_vsize); + return ret; +} +#endif + static const struct user_regset riscv_user_regset[] = { [REGSET_X] = { .core_note_type = NT_PRSTATUS, @@ -100,6 +168,17 @@ static const struct user_regset riscv_user_regset[] = { .set = riscv_fpr_set, }, #endif +#ifdef CONFIG_RISCV_ISA_V + [REGSET_V] = { + .core_note_type = NT_RISCV_VECTOR, + .align = 16, + .n = ((32 * RISCV_MAX_VLENB) + + sizeof(struct __riscv_v_regset_state)) / sizeof(__u32), + .size = sizeof(__u32), + .regset_get = riscv_vr_get, + .set = riscv_vr_set, + }, +#endif };
static const struct user_regset_view riscv_user_native_view = { diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index e0e159138331..20e285fdbc46 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -443,6 +443,8 @@ typedef struct elf64_shdr { #define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */ #define NT_MIPS_FP_MODE 0x801 /* MIPS floating-point mode */ #define NT_MIPS_MSA 0x802 /* MIPS SIMD registers */ +#define NT_RISCV_CSR 0x900 /* RISC-V Control and Status Registers */ +#define NT_RISCV_VECTOR 0x901 /* RISC-V vector registers */ #define NT_LOONGARCH_CPUCFG 0xa00 /* LoongArch CPU config registers */ #define NT_LOONGARCH_CSR 0xa01 /* LoongArch control and status registers */ #define NT_LOONGARCH_LSX 0xa02 /* LoongArch Loongson SIMD Extension registers */