Since SMP is not yet supported, it is acceptable to implement
smp_send_event_check_mask() as a stub.

Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
---
 xen/arch/riscv/smp.c   | 8 ++++++++
 xen/arch/riscv/stubs.c | 5 -----
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/xen/arch/riscv/smp.c b/xen/arch/riscv/smp.c
index 4ca6a4e89200..e727fdb09612 100644
--- a/xen/arch/riscv/smp.c
+++ b/xen/arch/riscv/smp.c
@@ -1,3 +1,4 @@
+#include <xen/cpumask.h>
 #include <xen/smp.h>
 
 /*
@@ -13,3 +14,10 @@
 struct pcpu_info pcpu_info[NR_CPUS] = { [0 ... NR_CPUS - 1] = {
     .processor_id = NR_CPUS,
 }};
+
+void smp_send_event_check_mask(const cpumask_t *mask)
+{
+#if CONFIG_NR_CPUS > 1
+# error "smp_send_event_check_mask() unimplemented"
+#endif
+}
diff --git a/xen/arch/riscv/stubs.c b/xen/arch/riscv/stubs.c
index eab826e8c3ae..6ebb5139de69 100644
--- a/xen/arch/riscv/stubs.c
+++ b/xen/arch/riscv/stubs.c
@@ -65,11 +65,6 @@ int arch_monitor_domctl_event(struct domain *d,
 
 /* smp.c */
 
-void smp_send_event_check_mask(const cpumask_t *mask)
-{
-    BUG_ON("unimplemented");
-}
-
 void smp_send_call_function_mask(const cpumask_t *mask)
 {
     BUG_ON("unimplemented");
-- 
2.52.0

On 24.12.2025 18:03, Oleksii Kurochko wrote:
> --- a/xen/arch/riscv/smp.c
> +++ b/xen/arch/riscv/smp.c
> @@ -1,3 +1,4 @@
> +#include <xen/cpumask.h>
>  #include <xen/smp.h>
>  
>  /*
> @@ -13,3 +14,10 @@
>  struct pcpu_info pcpu_info[NR_CPUS] = { [0 ... NR_CPUS - 1] = {
>      .processor_id = NR_CPUS,
>  }};
> +
> +void smp_send_event_check_mask(const cpumask_t *mask)
> +{
> +#if CONFIG_NR_CPUS > 1
> +# error "smp_send_event_check_mask() unimplemented"
> +#endif
> +}

CONFIG_NR_CPUS is 64 by default for 64-bit arch-es, from all I can tell, also
for RISC-V. And there's no "override" in riscv64_defconfig. How is the above
going to work in CI? Then again I must be overlooking something, as the config
used in CI has CONFIG_NR_CPUS=1. Just that I can't tell why that is.

And no, I'm not meaning to ask that you override NR_CPUS (and wherever such an
override would live, I think it would better be dropped rather sooner than
later). Instead an option may be this:

void smp_send_event_check_mask(const cpumask_t *mask)
{
#if CONFIG_NR_CPUS > 1
    BUG_ON(!cpumask_subset(mask, cpumask_of(0)));
#endif
}

(I can't tell off the top of my head whether an empty mask may be passed to this
function. If not, cpumask_equal() could be used as well.)

Of course the #if may then not be necessary at all, and a TODO comment may want
putting there instead.

Jan