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| author | Yijing Wang <wangyijing@huawei.com> | 2015-01-28 02:52:17 +0100 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2015-01-28 16:25:57 +0100 |
| commit | 6a878e5085fe97bd1e222b7883a1b815fcbbe4ed (patch) | |
| tree | 2ffcc34c8799f2c387c46c3441aa8c1072000e03 /arch/x86/pci | |
| parent | Linux 3.19-rc1 (diff) | |
| download | linux-6a878e5085fe97bd1e222b7883a1b815fcbbe4ed.tar.xz linux-6a878e5085fe97bd1e222b7883a1b815fcbbe4ed.zip | |
PCI: Fail MSI-X mappings if there's no space assigned to MSI-X BAR
Unlike MSI, which is configured via registers in the MSI capability in
Configuration Space, MSI-X is configured via tables in Memory Space.
These MSI-X tables are mapped by a device BAR, and if no Memory Space
has been assigned to the BAR, MSI-X cannot be used.
Fail MSI-X setup if no space has been assigned for the BAR.
Previously, we ioremapped the MSI-X table even if the resource hadn't been
assigned. In this case, the resource address is undefined (and is often
zero), which may lead to warnings or oopses in this path:
pci_enable_msix
msix_capability_init
msix_map_region
ioremap_nocache
The PCI core sets resource flags to zero when it can't assign space for the
resource (see reset_resource()). There are also some cases where it sets
the IORESOURCE_UNSET flag, e.g., pci_reassigndev_resource_alignment(),
pci_assign_resource(), etc. So we must check for both cases.
[bhelgaas: changelog]
Reported-by: Zhang Jukuo <zhangjukuo@huawei.com>
Tested-by: Zhang Jukuo <zhangjukuo@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'arch/x86/pci')
| -rw-r--r-- | arch/x86/pci/xen.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c index c489ef2c1a39..34fc4189ebf0 100644 --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -298,12 +298,16 @@ static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) map_irq.entry_nr = nvec; } else if (type == PCI_CAP_ID_MSIX) { int pos; + unsigned long flags; u32 table_offset, bir; pos = dev->msix_cap; pci_read_config_dword(dev, pos + PCI_MSIX_TABLE, &table_offset); bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR); + flags = pci_resource_flags(dev, bir); + if (!flags || (flags & IORESOURCE_UNSET)) + return -EINVAL; map_irq.table_base = pci_resource_start(dev, bir); map_irq.entry_nr = msidesc->msi_attrib.entry_nr; |