From: Thomas Gleixner tglx@linutronix.de
commit 9c8e9c9681a0f3f1ae90a90230d059c7a1dece5a upstream.
The recent rework of PCI/MSI[X] masking moved the non-mask checks from the low level accessors into the higher level mask/unmask functions.
This missed the fact that these accessors can be invoked from other places as well. The missing checks break XEN-PV which sets pci_msi_ignore_mask and also violates the virtual MSIX and the msi_attrib.maskbit protections.
Instead of sprinkling checks all over the place, lift them back into the low level accessor functions. To avoid checking three different conditions combine them into one property of msi_desc::msi_attrib.
[ josef: Fixed the missed conversion in the core code ]
Fixes: fcacdfbef5a1 ("PCI/MSI: Provide a new set of mask and unmask functions") Reported-by: Josef Johansson josef@oderland.se Signed-off-by: Thomas Gleixner tglx@linutronix.de Tested-by: Josef Johansson josef@oderland.se Cc: Bjorn Helgaas helgaas@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pci/msi.c | 26 ++++++++++++++------------ include/linux/msi.h | 2 +- kernel/irq/msi.c | 4 ++-- 3 files changed, 17 insertions(+), 15 deletions(-)
--- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -148,6 +148,9 @@ static noinline void pci_msi_update_mask raw_spinlock_t *lock = &desc->dev->msi_lock; unsigned long flags;
+ if (!desc->msi_attrib.can_mask) + return; + raw_spin_lock_irqsave(lock, flags); desc->msi_mask &= ~clear; desc->msi_mask |= set; @@ -181,7 +184,8 @@ static void pci_msix_write_vector_ctrl(s { void __iomem *desc_addr = pci_msix_desc_addr(desc);
- writel(ctrl, desc_addr + PCI_MSIX_ENTRY_VECTOR_CTRL); + if (desc->msi_attrib.can_mask) + writel(ctrl, desc_addr + PCI_MSIX_ENTRY_VECTOR_CTRL); }
static inline void pci_msix_mask(struct msi_desc *desc) @@ -200,23 +204,17 @@ static inline void pci_msix_unmask(struc
static void __pci_msi_mask_desc(struct msi_desc *desc, u32 mask) { - if (pci_msi_ignore_mask || desc->msi_attrib.is_virtual) - return; - if (desc->msi_attrib.is_msix) pci_msix_mask(desc); - else if (desc->msi_attrib.maskbit) + else pci_msi_mask(desc, mask); }
static void __pci_msi_unmask_desc(struct msi_desc *desc, u32 mask) { - if (pci_msi_ignore_mask || desc->msi_attrib.is_virtual) - return; - if (desc->msi_attrib.is_msix) pci_msix_unmask(desc); - else if (desc->msi_attrib.maskbit) + else pci_msi_unmask(desc, mask); }
@@ -484,7 +482,8 @@ msi_setup_entry(struct pci_dev *dev, int entry->msi_attrib.is_64 = !!(control & PCI_MSI_FLAGS_64BIT); entry->msi_attrib.is_virtual = 0; entry->msi_attrib.entry_nr = 0; - entry->msi_attrib.maskbit = !!(control & PCI_MSI_FLAGS_MASKBIT); + entry->msi_attrib.can_mask = !pci_msi_ignore_mask && + !!(control & PCI_MSI_FLAGS_MASKBIT); entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */ entry->msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1; entry->msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec)); @@ -495,7 +494,7 @@ msi_setup_entry(struct pci_dev *dev, int entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_32;
/* Save the initial mask status */ - if (entry->msi_attrib.maskbit) + if (entry->msi_attrib.can_mask) pci_read_config_dword(dev, entry->mask_pos, &entry->msi_mask);
out: @@ -638,10 +637,13 @@ static int msix_setup_entries(struct pci entry->msi_attrib.is_virtual = entry->msi_attrib.entry_nr >= vec_count;
+ entry->msi_attrib.can_mask = !pci_msi_ignore_mask && + !entry->msi_attrib.is_virtual; + entry->msi_attrib.default_irq = dev->irq; entry->mask_base = base;
- if (!entry->msi_attrib.is_virtual) { + if (entry->msi_attrib.can_mask) { addr = pci_msix_desc_addr(entry); entry->msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL); } --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -148,7 +148,7 @@ struct msi_desc { u8 is_msix : 1; u8 multiple : 3; u8 multi_cap : 3; - u8 maskbit : 1; + u8 can_mask : 1; u8 is_64 : 1; u8 is_virtual : 1; u16 entry_nr; --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -529,10 +529,10 @@ static bool msi_check_reservation_mode(s
/* * Checking the first MSI descriptor is sufficient. MSIX supports - * masking and MSI does so when the maskbit is set. + * masking and MSI does so when the can_mask attribute is set. */ desc = first_msi_entry(dev); - return desc->msi_attrib.is_msix || desc->msi_attrib.maskbit; + return desc->msi_attrib.is_msix || desc->msi_attrib.can_mask; }
int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,