Re: [PATCH 2/2] hw/riscv/virt.c: fix non-KVM --enable-debug build

[Daniel Henrique Barboza <dbarboza@ventanamicro.com>]

On 8/29/23 11:18, Philippe Mathieu-Daudé wrote:
> On 29/8/23 14:21, Daniel Henrique Barboza wrote:
>> A build with --enable-debug and without KVM will fail as follows:
>>
>> /usr/bin/ld: libqemu-riscv64-softmmu.fa.p/hw_riscv_virt.c.o: in function `virt_machine_init':
>> ./qemu/build/../hw/riscv/virt.c:1465: undefined reference to `kvm_riscv_aia_create'
>>
>> This happens because the code block with "if virt_use_kvm_aia(s)" isn't
>> being ignored by the debug build, resulting in an undefined reference to
>> a KVM only function.
>>
>> Add a stub for kvm_riscv_aia_create() in kvm_riscv.h when CONFIG_KVM is
>> false. Adding it as an inline instead of using kvm-stubs.c will make it
>> easier in the future to remember to add stubs for kvm functions that are
>> used in multiple accelerator code.
>>
>> Fixes: dbdb99948e ("target/riscv: select KVM AIA in riscv virt machine")
>> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
>> ---
>>   target/riscv/kvm_riscv.h | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
> 
> Similarly:
> 
> -- >8 --
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> @@ -79,7 +79,9 @@
>   /* KVM AIA only supports APLIC MSI. APLIC Wired is always emulated by QEMU. */
>   static bool virt_use_kvm_aia(RISCVVirtState *s)
>   {
> -    return kvm_irqchip_in_kernel() && s->aia_type == VIRT_AIA_TYPE_APLIC_IMSIC;
> +    return kvm_enabled()
> +        && kvm_irqchip_in_kernel()
> +        && s->aia_type == VIRT_AIA_TYPE_APLIC_IMSIC;
>   }
> ---

It doesn't work. Same error:

diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index 388e52a294..ac710006e7 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -79,7 +79,8 @@
  /* KVM AIA only supports APLIC MSI. APLIC Wired is always emulated by QEMU. */
  static bool virt_use_kvm_aia(RISCVVirtState *s)
  {
-    return kvm_irqchip_in_kernel() && s->aia_type == VIRT_AIA_TYPE_APLIC_IMSIC;
+    return kvm_enabled() &&
+           kvm_irqchip_in_kernel() && s->aia_type == VIRT_AIA_TYPE_APLIC_IMSIC;
  }
  
  static const MemMapEntry virt_memmap[] = {
diff --git a/target/riscv/kvm_riscv.h b/target/riscv/kvm_riscv.h
index 01be45cc69..7d4b7c60e2 100644
--- a/target/riscv/kvm_riscv.h
+++ b/target/riscv/kvm_riscv.h
@@ -22,19 +22,9 @@
  void kvm_riscv_init_user_properties(Object *cpu_obj);
  void kvm_riscv_reset_vcpu(RISCVCPU *cpu);
  void kvm_riscv_set_irq(RISCVCPU *cpu, int irq, int level);
-
-#ifdef CONFIG_KVM
  void kvm_riscv_aia_create(MachineState *machine, uint64_t group_shift,
                            uint64_t aia_irq_num, uint64_t aia_msi_num,
                            uint64_t aplic_base, uint64_t imsic_base,
                            uint64_t guest_num);
-#else
-static inline void kvm_riscv_aia_create(MachineState *machine,
-                                uint64_t group_shift, uint64_t aia_irq_num,
-                                uint64_t aia_msi_num, uint64_t aplic_base,
-                                uint64_t imsic_base, uint64_t guest_num) {
-    g_assert_not_reached();
-}
-#endif



/usr/bin/ld: libqemu-riscv64-softmmu.fa.p/hw_riscv_virt.c.o: in function `virt_machine_init':
/home/danielhb/work/qemu/build/../hw/riscv/virt.c:1466: undefined reference to `kvm_riscv_aia_create'
collect2: error: ld returned 1 exit status


I'm no compiler expert by any means but it seems that the --enable-debug build does not strip things
out like the usual build does, e.g. it won't elide a 'if kvm_enabled()' block out by checking that
kvm_enabled() is always false.


Thanks,

Daniel


> 
> ?