Re: [Qemu-devel] [PATCH 5/8] [PATCH RFC v3] s390-qemu: cpu hotplug - ipi_states enhancements

[Alexander Graf]

On 01.08.2013, at 16:12, Jason J. Herne wrote:

> From: "Jason J. Herne" <address@hidden>
> 
> Modify s390_cpu_addr2state to allow fetching state information for cpu 
> addresses
> above smp_cpus.  Hotplug requires this capability.
> 
> Also add s390_cpu_set_state function to allow modification of ipi_state 
> entries
> during hotplug.
> 
> Signed-off-by: Jason J. Herne <address@hidden>
> ---
> hw/s390x/s390-virtio.c |    9 +++++----
> target-s390x/cpu.h     |    2 +-
> 2 files changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/s390x/s390-virtio.c b/hw/s390x/s390-virtio.c
> index 21e9124..5ad9cf3 100644
> --- a/hw/s390x/s390-virtio.c
> +++ b/hw/s390x/s390-virtio.c
> @@ -54,12 +54,13 @@
> static VirtIOS390Bus *s390_bus;
> static S390CPU **ipi_states;
> 
> -S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
> +void s390_cpu_set_ipistate(uint16_t cpu_addr, S390CPU *state)
> {
> -    if (cpu_addr >= smp_cpus) {
> -        return NULL;
> -    }
> +    ipi_states[cpu_addr] = state;

We should still ensure that we don't access anything beyond the size of the 
array, no?


Alex

> +}
> 
> +S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
> +{
>     return ipi_states[cpu_addr];
> }
> 
> diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
> index 877eac7..62eb810 100644
> --- a/target-s390x/cpu.h
> +++ b/target-s390x/cpu.h
> @@ -377,7 +377,7 @@ static inline void kvm_s390_interrupt_internal(S390CPU 
> *cpu, int type,
> 
> uint8_t *s390_get_storage_keys(void);
> void s390_alloc_storage_keys(ram_addr_t ram_size);
> -
> +void s390_cpu_set_ipistate(uint16_t cpu_addr, S390CPU *state);
> S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
> void s390_add_running_cpu(S390CPU *cpu);
> unsigned s390_del_running_cpu(S390CPU *cpu);
> -- 
> 1.7.10.4
>