On 2011-10-17 13:10, Michael S. Tsirkin wrote: > On Mon, Oct 17, 2011 at 11:27:40AM +0200, Jan Kiszka wrote: >> Only accesses to the MSI-X table must trigger a call to >> msix_handle_mask_update or a notifier invocation. >> >> Signed-off-by: Jan Kiszka <jan.kis...@siemens.com> > > Why would msix_mmio_write be called on an access > outside the table?
Because it handles both the table and the PBA. > >> --- >> hw/msix.c | 16 ++++++++++------ >> 1 files changed, 10 insertions(+), 6 deletions(-) >> >> diff --git a/hw/msix.c b/hw/msix.c >> index 2c4de21..33cb716 100644 >> --- a/hw/msix.c >> +++ b/hw/msix.c >> @@ -264,18 +264,22 @@ static void msix_mmio_write(void *opaque, >> target_phys_addr_t addr, >> { >> PCIDevice *dev = opaque; >> unsigned int offset = addr & (MSIX_PAGE_SIZE - 1) & ~0x3; >> - int vector = offset / PCI_MSIX_ENTRY_SIZE; >> + unsigned int vector = offset / PCI_MSIX_ENTRY_SIZE; > > Why the int/unsigned change? this has no chance to overflow, and using > unsigned causes signed/unsigned comparison below, > and unsigned/signed conversion on calls such as msix_is_masked. Vectors should be unsigned int, this is just one step in that direction as we are at it. Even if the overflow is practically impossible, this remains cleaner. > >> int was_masked = msix_is_masked(dev, vector); >> pci_set_long(dev->msix_table_page + offset, val); >> if (kvm_enabled() && kvm_irqchip_in_kernel()) { >> kvm_msix_update(dev, vector, was_masked, msix_is_masked(dev, >> vector)); >> } > > I would say if we need to check the address, check it first thing > and return if the address is out of a sensible range. Will do that later when generalized MSI-X support. > For example, are you worried about kvm_msix_update calls with > a sensible mask? No, that kvm code will die anyway. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html