[PATCH v2 1/6] ACPI: RISC-V: Fix riscv_acpi_irq_get_dep() loop termination

[Lorenzo Pieralisi]

On Mon, Jun 08, 2026 at 09:54:28PM +0530, Sunil V L wrote:
> Hi Lorenzo,
> 
> On Wed, Jun 3, 2026 at 1:51 PM Lorenzo Pieralisi <lpieralisi at kernel.org> wrote:
> >
> > In riscv_acpi_add_irq_dep() the main loop condition would currently stop
> > the loop if an interrupt descriptor contains an interrupt for which the
> > respective GSI handle is NULL, which is not correct because subsequent
> > interrupts in the interrupt descriptor might still have a GSI dependency
> > that must not be skipped.
> >
> > Rework riscv_acpi_add_irq_dep() and the riscv_acpi_irq_get_dep() call chain
> > to fix it - by not forcing the loop to stop in order to guarantee
> > dependency detection for all the interrupt entries in the CRS descriptor.
> >
> > Signed-off-by: Lorenzo Pieralisi <lpieralisi at kernel.org>
> > Cc: "Rafael J. Wysocki" <rafael at kernel.org>
> > Cc: Sunil V L <sunilvl at ventanamicro.com>
> > ---
> >  drivers/acpi/riscv/irq.c | 10 ++++++----
> >  1 file changed, 6 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/acpi/riscv/irq.c b/drivers/acpi/riscv/irq.c
> > index 9b88d0993e88..cd83c3035cf6 100644
> > --- a/drivers/acpi/riscv/irq.c
> > +++ b/drivers/acpi/riscv/irq.c
> > @@ -299,6 +299,7 @@ static acpi_status riscv_acpi_irq_get_parent(struct acpi_resource *ares, void *c
> >                         return AE_OK;
> >
> >                 ctx->handle = riscv_acpi_get_gsi_handle(eirq->interrupts[ctx->index]);
> > +               ctx->rc = 0;
> >                 return AE_CTRL_TERMINATE;
> >         }
> >
> > @@ -314,10 +315,8 @@ static int riscv_acpi_irq_get_dep(acpi_handle handle, unsigned int index, acpi_h
> >
> >         acpi_walk_resources(handle, METHOD_NAME__CRS, riscv_acpi_irq_get_parent, &ctx);
> >         *gsi_handle = ctx.handle;
> > -       if (*gsi_handle)
> > -               return 1;
> >
> > -       return 0;
> > +       return ctx.rc;
> >  }
> >
> >  static u32 riscv_acpi_add_prt_dep(acpi_handle handle)
> > @@ -381,8 +380,11 @@ static u32 riscv_acpi_add_irq_dep(acpi_handle handle)
> >         int i;
> >
> >         for (i = 0;
> > -            riscv_acpi_irq_get_dep(handle, i, &gsi_handle);
> > +            !riscv_acpi_irq_get_dep(handle, i, &gsi_handle);
> >              i++) {
> > +               if (!gsi_handle)
> > +                       continue;
> > +
> >                 dep_devices.count = 1;
> >                 dep_devices.handles = kzalloc_objs(*dep_devices.handles, 1);
> >                 if (!dep_devices.handles) {
> >
> Do these fixes need the Fixes tag?

I can add a Fixes: tag but I wanted first some help testing them, it
is code perusal that got me there.

> Otherwise, LGTM.
> Reviewed-by: Sunil V L <sunilvl at oss.qualcomm.com>

Thanks,
Lorenzo