From 04b090366ca59e8a75837c822df261a8d0bd1a30 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 5 Jan 2021 13:17:54 +0100 Subject: [PATCH] x86/vPCI: tolerate (un)masking a disabled MSI-X entry MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit None of the four reasons causing vpci_msix_arch_mask_entry() to get called (there's just a single call site) are impossible or illegal prior to an entry actually having got set up: - the entry may remain masked (in this case, however, a prior masked -> unmasked transition would already not have worked), - MSI-X may not be enabled, - the global mask bit may be set, - the entry may not otherwise have been updated. Hence the function asserting that the entry was previously set up was simply wrong. Since the caller tracks the masked state (and setting up of an entry would only be effected when that software bit is clear), it's okay to skip both masking and unmasking requests in this case. Fixes: d6281be9d0145 ('vpci/msix: add MSI-X handlers') Reported-by: Manuel Bouyer Signed-off-by: Jan Beulich Reviewed-by: Roger Pau Monné Tested-by: Manuel Bouyer --- xen/arch/x86/hvm/vmsi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/hvm/vmsi.c b/xen/arch/x86/hvm/vmsi.c index 7ca19353ab..ddcfc6c229 100644 --- a/xen/arch/x86/hvm/vmsi.c +++ b/xen/arch/x86/hvm/vmsi.c @@ -840,8 +840,8 @@ void vpci_msi_arch_print(const struct vpci_msi *msi) void vpci_msix_arch_mask_entry(struct vpci_msix_entry *entry, const struct pci_dev *pdev, bool mask) { - ASSERT(entry->arch.pirq != INVALID_PIRQ); - vpci_mask_pirq(pdev->domain, entry->arch.pirq, mask); + if ( entry->arch.pirq != INVALID_PIRQ ) + vpci_mask_pirq(pdev->domain, entry->arch.pirq, mask); } int vpci_msix_arch_enable_entry(struct vpci_msix_entry *entry, -- 2.30.2