From f9fdf9077c2a6d7d2bfc5ccfcd961f60d311218d Mon Sep 17 00:00:00 2001 From: Deepak Gupta Date: Tue, 8 Oct 2024 15:50:02 -0700 Subject: [PATCH] target/riscv: tb flag for shadow stack instructions Shadow stack instructions can be decoded as zimop / zcmop or shadow stack instructions depending on whether shadow stack are enabled at current privilege. This requires a TB flag so that correct TB generation and correct TB lookup happens. `DisasContext` gets a field indicating whether bcfi is enabled or not. Signed-off-by: Deepak Gupta Co-developed-by: Jim Shu Co-developed-by: Andy Chiu Reviewed-by: Richard Henderson Reviewed-by: Alistair Francis Message-ID: <20241008225010.1861630-13-debug@rivosinc.com> Signed-off-by: Alistair Francis --- target/riscv/cpu.h | 2 ++ target/riscv/cpu_helper.c | 4 ++++ target/riscv/translate.c | 3 +++ 3 files changed, 9 insertions(+) diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 195eac81c0..47e7a91667 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -628,6 +628,8 @@ FIELD(TB_FLAGS, AXL, 26, 2) /* zicfilp needs a TB flag to track indirect branches */ FIELD(TB_FLAGS, FCFI_ENABLED, 28, 1) FIELD(TB_FLAGS, FCFI_LP_EXPECTED, 29, 1) +/* zicfiss needs a TB flag so that correct TB is located based on tb flags */ +FIELD(TB_FLAGS, BCFI_ENABLED, 30, 1) #ifdef TARGET_RISCV32 #define riscv_cpu_mxl(env) ((void)(env), MXL_RV32) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index b42abedf9e..8a30031872 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -171,6 +171,10 @@ void cpu_get_tb_cpu_state(CPURISCVState *env, vaddr *pc, flags = FIELD_DP32(flags, TB_FLAGS, FCFI_ENABLED, 1); } + if (cpu_get_bcfien(env)) { + flags = FIELD_DP32(flags, TB_FLAGS, BCFI_ENABLED, 1); + } + #ifdef CONFIG_USER_ONLY fs = EXT_STATUS_DIRTY; vs = EXT_STATUS_DIRTY; diff --git a/target/riscv/translate.c b/target/riscv/translate.c index b5c0511b4b..afa2ed4e3a 100644 --- a/target/riscv/translate.c +++ b/target/riscv/translate.c @@ -119,6 +119,8 @@ typedef struct DisasContext { /* zicfilp extension. fcfi_enabled, lp expected or not */ bool fcfi_enabled; bool fcfi_lp_expected; + /* zicfiss extension, if shadow stack was enabled during TB gen */ + bool bcfi_enabled; } DisasContext; static inline bool has_ext(DisasContext *ctx, uint32_t ext) @@ -1241,6 +1243,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs) ctx->pm_base_enabled = FIELD_EX32(tb_flags, TB_FLAGS, PM_BASE_ENABLED); ctx->ztso = cpu->cfg.ext_ztso; ctx->itrigger = FIELD_EX32(tb_flags, TB_FLAGS, ITRIGGER); + ctx->bcfi_enabled = FIELD_EX32(tb_flags, TB_FLAGS, BCFI_ENABLED); ctx->fcfi_lp_expected = FIELD_EX32(tb_flags, TB_FLAGS, FCFI_LP_EXPECTED); ctx->fcfi_enabled = FIELD_EX32(tb_flags, TB_FLAGS, FCFI_ENABLED); ctx->zero = tcg_constant_tl(0);