From 6c796996ee7033bcbbc3cd733513eb43f8160f5e Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 16 Jan 2023 19:11:32 +0100 Subject: [PATCH] x86/pci/xen: Fixup fallout from the PCI/MSI overhaul David reported that the recent PCI/MSI rework results in MSI descriptor leakage under XEN. This is caused by: 1) The missing MSI_FLAG_FREE_MSI_DESCS flag in the XEN MSI domain info, which is required now that PCI/MSI delegates descriptor freeing to the core MSI code. 2) Not disassociating the interrupts on teardown, by setting the msi_desc::irq to 0. This was not required before because the teardown was unconditional and did not check whether a MSI descriptor was still connected to a Linux interrupt. On further inspection it came to light that the MSI_FLAG_DEV_SYSFS is missing in the XEN MSI domain info as well to restore the pre 6.2 status quo. Add the missing MSI flags and disassociate the MSI descriptor from the Linux interrupt in the XEN specific teardown function. Fixes: b2bdda205c0c ("PCI/MSI: Let the MSI core free descriptors") Fixes: 2f2940d16823 ("genirq/msi: Remove filter from msi_free_descs_free_range()") Fixes: ffd84485e6be ("PCI/MSI: Let the irq code handle sysfs groups") Reported-by: David Woodhouse Signed-off-by: Thomas Gleixner Tested-by: David Woodhouse Link: https://lore.kernel.org/r/871qnunycr.ffs@tglx --- arch/x86/pci/xen.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c index 790550479831..8babce71915f 100644 --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -392,6 +392,7 @@ static void xen_teardown_msi_irqs(struct pci_dev *dev) msi_for_each_desc(msidesc, &dev->dev, MSI_DESC_ASSOCIATED) { for (i = 0; i < msidesc->nvec_used; i++) xen_destroy_irq(msidesc->irq + i); + msidesc->irq = 0; } } @@ -433,7 +434,7 @@ static struct msi_domain_ops xen_pci_msi_domain_ops = { }; static struct msi_domain_info xen_pci_msi_domain_info = { - .flags = MSI_FLAG_PCI_MSIX, + .flags = MSI_FLAG_PCI_MSIX | MSI_FLAG_FREE_MSI_DESCS | MSI_FLAG_DEV_SYSFS, .ops = &xen_pci_msi_domain_ops, };