From: Claudio Fontana <cfont...@suse.de> cc->do_interrupt is in theory a TCG callback used in accel/tcg only, to prepare the emulated architecture to take an interrupt as defined in the hardware specifications,
but in reality the _do_interrupt style of functions in targets are also occasionally reused by KVM to prepare the architecture state in a similar way where userspace code has identified that it needs to deliver an exception to the guest. In the case of ARM, that includes: 1) the vcpu thread got a SIGBUS indicating a memory error, and we need to deliver a Synchronous External Abort to the guest to let it know about the error. 2) the kernel told us about a debug exception (breakpoint, watchpoint) but it is not for one of QEMU's own gdbstub breakpoints/watchpoints so it must be a breakpoint the guest itself has set up, therefore we need to deliver it to the guest. So in order to reuse code, the same arm_do_interrupt function is used. This is all fine, but we need to avoid calling it using the callback registered in CPUClass, since that one is now TCG-only. Fortunately this is easily solved by replacing calls to CPUClass::do_interrupt() with explicit calls to arm_do_interrupt(). Signed-off-by: Claudio Fontana <cfont...@suse.de> Reviewed-by: Alex Bennée <alex.ben...@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com> Reviewed-by: Richard Henderson <richard.hender...@linaro.org> Cc: Peter Maydell <peter.mayd...@linaro.org> Message-Id: <20210204163931.7358-9-cfont...@suse.de> Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- target/arm/helper.c | 4 ++++ target/arm/kvm64.c | 6 ++---- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/target/arm/helper.c b/target/arm/helper.c index 47e266d7e6..1a64bd748c 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -9969,6 +9969,10 @@ static void handle_semihosting(CPUState *cs) * Do any appropriate logging, handle PSCI calls, and then hand off * to the AArch64-entry or AArch32-entry function depending on the * target exception level's register width. + * + * Note: this is used for both TCG (as the do_interrupt tcg op), + * and KVM to re-inject guest debug exceptions, and to + * inject a Synchronous-External-Abort. */ void arm_cpu_do_interrupt(CPUState *cs) { diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c index 3c37fc4fb6..dff85f6db9 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -946,7 +946,6 @@ static void kvm_inject_arm_sea(CPUState *c) { ARMCPU *cpu = ARM_CPU(c); CPUARMState *env = &cpu->env; - CPUClass *cc = CPU_GET_CLASS(c); uint32_t esr; bool same_el; @@ -962,7 +961,7 @@ static void kvm_inject_arm_sea(CPUState *c) env->exception.syndrome = esr; - cc->do_interrupt(c); + arm_cpu_do_interrupt(c); } #define AARCH64_CORE_REG(x) (KVM_REG_ARM64 | KVM_REG_SIZE_U64 | \ @@ -1493,7 +1492,6 @@ bool kvm_arm_handle_debug(CPUState *cs, struct kvm_debug_exit_arch *debug_exit) { int hsr_ec = syn_get_ec(debug_exit->hsr); ARMCPU *cpu = ARM_CPU(cs); - CPUClass *cc = CPU_GET_CLASS(cs); CPUARMState *env = &cpu->env; /* Ensure PC is synchronised */ @@ -1547,7 +1545,7 @@ bool kvm_arm_handle_debug(CPUState *cs, struct kvm_debug_exit_arch *debug_exit) env->exception.vaddress = debug_exit->far; env->exception.target_el = 1; qemu_mutex_lock_iothread(); - cc->do_interrupt(cs); + arm_cpu_do_interrupt(cs); qemu_mutex_unlock_iothread(); return false; -- 2.25.1