On Tue, Dec 03, 2024 at 05:50:13PM +0100, Thomas Gleixner wrote: > On Tue, Dec 03 2024 at 17:27, Andrew Jones wrote: > > On Tue, Dec 03, 2024 at 02:53:45PM +0100, Thomas Gleixner wrote: > >> On Thu, Nov 14 2024 at 17:18, Andrew Jones wrote: > >> The whole IMSIC MSI support can be moved over to MSI LIB which makes all > >> of this indirection go away and your intermediate domain will just fit > >> in. > >> > >> Uncompiled patch below. If that works, it needs to be split up properly. > > > > Thanks Thomas. I gave your patch below a go, but we now fail to have an > > msi domain set up when probing devices which go through aplic_msi_setup(), > > resulting in an immediate NULL deference in > > msi_create_device_irq_domain(). I'll look closer tomorrow. > > Duh! I forgot to update the .select callback. I don't know how you fixed that > compile fail up. Delta patch below. > > Thanks, > > tglx > --- > --- a/drivers/irqchip/irq-riscv-imsic-platform.c > +++ b/drivers/irqchip/irq-riscv-imsic-platform.c > @@ -180,7 +180,7 @@ static void imsic_irq_debug_show(struct > static const struct irq_domain_ops imsic_base_domain_ops = { > .alloc = imsic_irq_domain_alloc, > .free = imsic_irq_domain_free, > - .select = imsic_irq_domain_select, > + .select = msi_lib_irq_domain_select, > #ifdef CONFIG_GENERIC_IRQ_DEBUGFS > .debug_show = imsic_irq_debug_show, > #endif Hi Thomas, With this select fix and replacing patch 03/15 of this series with the following diff, this irqbypass PoC still works. Based on what Anup said, I kept imsic_msi_update_msg(), which means I kept this entire patch (01/15) as is. Anup is working on a series to fix the non-atomic MSI message writes to the device and will likely pick this patch up along with your changes to convert IMSIC to msi-lib. I'd like to know your opinion on patch 02/15 of this series and the diff below. afaict, x86 does something similar with the DOMAIN_BUS_DMAR and DOMAIN_BUS_AMDVI tokens in x86_init_dev_msi_info(). Thanks, drew diff --git a/drivers/irqchip/irq-msi-lib.c b/drivers/irqchip/irq-msi-lib.c index 51464c6257f3..cc18516a4e82 100644 --- a/drivers/irqchip/irq-msi-lib.c +++ b/drivers/irqchip/irq-msi-lib.c @@ -36,14 +36,14 @@ bool msi_lib_init_dev_msi_info(struct device *dev, struct irq_domain *domain, return false; /* - * MSI parent domain specific settings. For now there is only the - * root parent domain, e.g. NEXUS, acting as a MSI parent, but it is - * possible to stack MSI parents. See x86 vector -> irq remapping + * MSI parent domain specific settings. There may be only the root + * parent domain, e.g. NEXUS, acting as a MSI parent, or there may + * be stacked MSI parents, typically used for remapping. */ if (domain->bus_token == pops->bus_select_token) { if (WARN_ON_ONCE(domain != real_parent)) return false; - } else { + } else if (real_parent->bus_token != DOMAIN_BUS_MSI_REMAP) { WARN_ON_ONCE(1); return false; }