From: Cédric Le Goater clg@kaod.org
commit 8e80a73fa9a7747e3e8255cb149c543aabf65a24 upstream.
Commit 4f86a06e2d6e ("irqdomain: Make normal and nomap irqdomains exclusive") introduced an IRQ_DOMAIN_FLAG_NO_MAP flag to isolate the 'nomap' domains still in use under the powerpc arch. With this new flag, the revmap_tree of the IRQ domain is not used anymore. This change broke the support of shared LSIs [1] in the XIVE driver because it was relying on a lookup in the revmap_tree to query previously mapped interrupts. Linux now creates two distinct IRQ mappings on the same HW IRQ which can lead to unexpected behavior in the drivers.
The XIVE IRQ domain is not a direct mapping domain and its HW IRQ interrupt number space is rather large : 1M/socket on POWER9 and POWER10, change the XIVE driver to use a 'tree' domain type instead.
[1] For instance, a linux KVM guest with virtio-rng and virtio-balloon devices.
Fixes: 4f86a06e2d6e ("irqdomain: Make normal and nomap irqdomains exclusive") Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Cédric Le Goater clg@kaod.org Tested-by: Greg Kurz groug@kaod.org Acked-by: Marc Zyngier maz@kernel.org Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20211116134022.420412-1-clg@kaod.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/sysdev/xive/Kconfig | 1 - arch/powerpc/sysdev/xive/common.c | 3 +-- 2 files changed, 1 insertion(+), 3 deletions(-)
--- a/arch/powerpc/sysdev/xive/Kconfig +++ b/arch/powerpc/sysdev/xive/Kconfig @@ -3,7 +3,6 @@ config PPC_XIVE bool select PPC_SMP_MUXED_IPI select HARDIRQS_SW_RESEND - select IRQ_DOMAIN_NOMAP
config PPC_XIVE_NATIVE bool --- a/arch/powerpc/sysdev/xive/common.c +++ b/arch/powerpc/sysdev/xive/common.c @@ -1443,8 +1443,7 @@ static const struct irq_domain_ops xive_
static void __init xive_init_host(struct device_node *np) { - xive_irq_domain = irq_domain_add_nomap(np, XIVE_MAX_IRQ, - &xive_irq_domain_ops, NULL); + xive_irq_domain = irq_domain_add_tree(np, &xive_irq_domain_ops, NULL); if (WARN_ON(xive_irq_domain == NULL)) return; irq_set_default_host(xive_irq_domain);