| Message ID | 1447345251-22625-4-git-send-email-alex.bennee@linaro.org |
|---|---|
| State | New |
| Headers | show |
On 12 November 2015 at 16:20, Alex Bennée <alex.bennee@linaro.org> wrote: > This adds support for single-step. There isn't much to do on the QEMU > side as after we set-up the request for single step via the debug ioctl > it is all handled within the kernel. > > Signed-off-by: Alex Bennée <alex.bennee@linaro.org> > > --- > v2 > - convert to using HSR_EC > v3 > - use internals.h definitions > --- > target-arm/kvm.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/target-arm/kvm.c b/target-arm/kvm.c > index 50f70ef..d505a7e 100644 > --- a/target-arm/kvm.c > +++ b/target-arm/kvm.c > @@ -535,6 +535,13 @@ static int kvm_handle_debug(CPUState *cs, struct kvm_run *run) > kvm_cpu_synchronize_state(cs); > > switch (hsr_ec) { > + case EC_SOFTWARESTEP: > + if (cs->singlestep_enabled) { > + return true; > + } else { > + error_report("Came out of SINGLE STEP when not enabled"); > + } > + break; > case EC_AA64_BKPT: > if (kvm_find_sw_breakpoint(cs, env->pc)) { > return true; > @@ -595,6 +602,9 @@ int kvm_arch_on_sigbus(int code, void *addr) > > void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg) > { > + if (cs->singlestep_enabled) { > + dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP; > + } Doesn't kvm_update_guest_debug() already set these bits, or am I misreading it? > if (kvm_sw_breakpoints_active(cs)) { > dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP; > } > -- > 2.6.3 thanks -- PMM
Peter Maydell <peter.maydell@linaro.org> writes: > On 12 November 2015 at 16:20, Alex Bennée <alex.bennee@linaro.org> wrote: >> This adds support for single-step. There isn't much to do on the QEMU >> side as after we set-up the request for single step via the debug ioctl >> it is all handled within the kernel. >> >> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> >> >> --- >> v2 >> - convert to using HSR_EC >> v3 >> - use internals.h definitions >> --- >> target-arm/kvm.c | 10 ++++++++++ >> 1 file changed, 10 insertions(+) >> >> diff --git a/target-arm/kvm.c b/target-arm/kvm.c >> index 50f70ef..d505a7e 100644 >> --- a/target-arm/kvm.c >> +++ b/target-arm/kvm.c >> @@ -535,6 +535,13 @@ static int kvm_handle_debug(CPUState *cs, struct kvm_run *run) >> kvm_cpu_synchronize_state(cs); >> >> switch (hsr_ec) { >> + case EC_SOFTWARESTEP: >> + if (cs->singlestep_enabled) { >> + return true; >> + } else { >> + error_report("Came out of SINGLE STEP when not enabled"); >> + } >> + break; >> case EC_AA64_BKPT: >> if (kvm_find_sw_breakpoint(cs, env->pc)) { >> return true; >> @@ -595,6 +602,9 @@ int kvm_arch_on_sigbus(int code, void *addr) >> >> void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg) >> { >> + if (cs->singlestep_enabled) { >> + dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP; >> + } > > Doesn't kvm_update_guest_debug() already set these bits, or am > I misreading it? Yeah. This raises an interesting problem about what to do when we don't have the capability. I could suppress those bits in the update function but that seems a bit hacky. Looking at the GDB capability code there doesn't seem to report breakpoint capability short of just failing when you try to set one. > >> if (kvm_sw_breakpoints_active(cs)) { >> dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP; >> } >> -- >> 2.6.3 > > thanks > -- PMM -- Alex Bennée
diff --git a/target-arm/kvm.c b/target-arm/kvm.c index 50f70ef..d505a7e 100644 --- a/target-arm/kvm.c +++ b/target-arm/kvm.c @@ -535,6 +535,13 @@ static int kvm_handle_debug(CPUState *cs, struct kvm_run *run) kvm_cpu_synchronize_state(cs); switch (hsr_ec) { + case EC_SOFTWARESTEP: + if (cs->singlestep_enabled) { + return true; + } else { + error_report("Came out of SINGLE STEP when not enabled"); + } + break; case EC_AA64_BKPT: if (kvm_find_sw_breakpoint(cs, env->pc)) { return true; @@ -595,6 +602,9 @@ int kvm_arch_on_sigbus(int code, void *addr) void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg) { + if (cs->singlestep_enabled) { + dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP; + } if (kvm_sw_breakpoints_active(cs)) { dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP; }
This adds support for single-step. There isn't much to do on the QEMU side as after we set-up the request for single step via the debug ioctl it is all handled within the kernel. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> --- v2 - convert to using HSR_EC v3 - use internals.h definitions --- target-arm/kvm.c | 10 ++++++++++ 1 file changed, 10 insertions(+)