From e13886e3a790b52f0b2e93cb5e84fdc2ada5471a Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 28 Feb 2017 12:08:19 +0000 Subject: [PATCH] armv7m: Raise correct kind of UsageFault for attempts to execute ARM code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit M profile doesn't implement ARM, and the architecturally required behaviour for attempts to execute with the Thumb bit clear is to generate a UsageFault with the CFSR INVSTATE bit set. We were incorrectly implementing this as generating an UNDEFINSTR UsageFault; fix this. Signed-off-by: Peter Maydell Reviewed-by: Alex Bennée --- linux-user/main.c | 1 + target/arm/cpu.h | 1 + target/arm/helper.c | 4 ++++ target/arm/translate.c | 8 ++++++-- 4 files changed, 12 insertions(+), 2 deletions(-) diff --git a/linux-user/main.c b/linux-user/main.c index 9645122aa6..10a3bb3a12 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -574,6 +574,7 @@ void cpu_loop(CPUARMState *env) switch(trapnr) { case EXCP_UDEF: case EXCP_NOCP: + case EXCP_INVSTATE: { TaskState *ts = cs->opaque; uint32_t opcode; diff --git a/target/arm/cpu.h b/target/arm/cpu.h index 045830aeae..9e7b2dfc83 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -57,6 +57,7 @@ #define EXCP_VFIQ 15 #define EXCP_SEMIHOST 16 /* semihosting call */ #define EXCP_NOCP 17 /* v7M NOCP UsageFault */ +#define EXCP_INVSTATE 18 /* v7M INVSTATE UsageFault */ #define ARMV7M_EXCP_RESET 1 #define ARMV7M_EXCP_NMI 2 diff --git a/target/arm/helper.c b/target/arm/helper.c index 9081771656..3f4211b572 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -6245,6 +6245,10 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE); env->v7m.cfsr |= R_V7M_CFSR_NOCP_MASK; break; + case EXCP_INVSTATE: + armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE); + env->v7m.cfsr |= R_V7M_CFSR_INVSTATE_MASK; + break; case EXCP_SWI: /* The PC already points to the next instruction. */ armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_SVC); diff --git a/target/arm/translate.c b/target/arm/translate.c index abc1f77ee4..b859f10755 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -7990,9 +7990,13 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn) TCGv_i32 addr; TCGv_i64 tmp64; - /* M variants do not implement ARM mode. */ + /* M variants do not implement ARM mode; this must raise the INVSTATE + * UsageFault exception. + */ if (arm_dc_feature(s, ARM_FEATURE_M)) { - goto illegal_op; + gen_exception_insn(s, 4, EXCP_INVSTATE, syn_uncategorized(), + default_exception_el(s)); + return; } cond = insn >> 28; if (cond == 0xf){ -- GitLab