The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: 70245f86c109e0eafb92ea9653184c0e44b4b35c Gitweb: https://git.kernel.org/tip/70245f86c109e0eafb92ea9653184c0e44b4b35c Author: Thomas Gleixner tglx@linutronix.de AuthorDate: Wed, 10 Feb 2021 16:27:41 +01:00 Committer: Thomas Gleixner tglx@linutronix.de CommitterDate: Wed, 10 Feb 2021 22:06:47 +01:00

x86/pci: Create PCI/MSI irqdomain after x86_init.pci.arch_init()

Invoking x86_init.irqs.create_pci_msi_domain() before x86_init.pci.arch_init() breaks XEN PV.

The XEN_PV specific pci.arch_init() function overrides the default create_pci_msi_domain() which is obviously too late.

As a consequence the XEN PV PCI/MSI allocation goes through the native path which runs out of vectors and causes malfunction.

Invoke it after x86_init.pci.arch_init().

Fixes: 6b15ffa07dc3 ("x86/irq: Initialize PCI/MSI domain at PCI init time") Reported-by: Juergen Gross jgross@suse.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Tested-by: Juergen Gross jgross@suse.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/87pn18djte.fsf@nanos.tec.linutronix.de --- arch/x86/pci/init.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/x86/pci/init.c b/arch/x86/pci/init.c index 00bfa1e..0bb3b8b 100644 --- a/arch/x86/pci/init.c +++ b/arch/x86/pci/init.c @@ -9,16 +9,23 @@ in the right sequence from here. */ static __init int pci_arch_init(void) { - int type; - - x86_create_pci_msi_domain(); + int type, pcbios = 1;

type = pci_direct_probe();

if (!(pci_probe & PCI_PROBE_NOEARLY)) pci_mmcfg_early_init();

- if (x86_init.pci.arch_init && !x86_init.pci.arch_init()) + if (x86_init.pci.arch_init) + pcbios = x86_init.pci.arch_init(); + + /* + * Must happen after x86_init.pci.arch_init(). Xen sets up the + * x86_init.irqs.create_pci_msi_domain there. + */ + x86_create_pci_msi_domain(); + + if (!pcbios) return 0;

pci_pcbios_init();