From: Marc Zyngier <maz@kernel.org> stable inclusion from stable-5.10.81 commit f28c620e1ac1b7312519516217240556193c2618 bugzilla: 185832 https://gitee.com/openeuler/kernel/issues/I4L9CF Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 2226667a145db2e1f314d7f57fd644fe69863ab9 upstream. It appears that some devices are lying about their mask capability, pretending that they don't have it, while they actually do. The net result is that now that we don't enable MSIs on such endpoint. Add a new per-device flag to deal with this. Further patches will make use of it, sadly. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20211104180130.3825416-2-maz@kernel.org Cc: Bjorn Helgaas <helgaas@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/pci/msi.c | 3 +++ include/linux/pci.h | 2 ++ 2 files changed, 5 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 2982403e3213..db7475dc601f 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -592,6 +592,9 @@ msi_setup_entry(struct pci_dev *dev, int nvec, struct irq_affinity *affd) goto out; pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); + /* Lies, damned lies, and MSIs */ + if (dev->dev_flags & PCI_DEV_FLAGS_HAS_MSI_MASKING) + control |= PCI_MSI_FLAGS_MASKBIT; entry->msi_attrib.is_msix = 0; entry->msi_attrib.is_64 = !!(control & PCI_MSI_FLAGS_64BIT); diff --git a/include/linux/pci.h b/include/linux/pci.h index 9ed3d45ccb82..774cf41565a5 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -227,6 +227,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_NO_FLR_RESET = (__force pci_dev_flags_t) (1 << 10), /* Don't use Relaxed Ordering for TLPs directed at this device */ PCI_DEV_FLAGS_NO_RELAXED_ORDERING = (__force pci_dev_flags_t) (1 << 11), + /* Device does honor MSI masking despite saying otherwise */ + PCI_DEV_FLAGS_HAS_MSI_MASKING = (__force pci_dev_flags_t) (1 << 12), }; enum pci_irq_reroute_variant { -- 2.20.1