Re: [Qemu-devel] [PATCH] hw/iommu: Fix problems reported by Coverity scan

[Stefan Weil]

Hi,

On 10/01/16 17:57, David Kiarie wrote:
> Signed-off-by: David Kiarie <address@hidden>
> ---
>  hw/i386/amd_iommu.c | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
> index 023de52..815d45f 100644
> --- a/hw/i386/amd_iommu.c
> +++ b/hw/i386/amd_iommu.c
> @@ -144,7 +144,7 @@ static void amdvi_assign_andq(AMDVIState *s, hwaddr addr, 
> uint64_t val)
>  static void amdvi_generate_msi_interrupt(AMDVIState *s)
>  {
>      MSIMessage msg;
> -    MemTxAttrs attrs;
> +    MemTxAttrs attrs = {0, 0};
>
>      attrs.requester_id = pci_requester_id(&s->pci.dev);
>
> @@ -185,7 +185,7 @@ static void amdvi_setevent_bits(uint64_t *buffer, uint64_t 
> value, int start,
>                                  int length)
>  {
>      int index = start / 64, bitpos = start % 64;
> -    uint64_t mask = ((1 << length) - 1) << bitpos;
> +    uint64_t mask = ((1UL << length) - 1) << bitpos;
>      buffer[index] &= ~mask;
>      buffer[index] |= (value << bitpos) & mask;
>  }
> @@ -334,7 +334,7 @@ static void amdvi_update_iotlb(AMDVIState *s, uint16_t 
> devid,
>                                 uint16_t domid)
>  {
>      AMDVIIOTLBEntry *entry = g_malloc(sizeof(*entry));
> -    uint64_t *key = g_malloc(sizeof(key));
> +    uint64_t *key = g_malloc(sizeof(*key));

I suggest using g_new(uint64_t, 1) here.

>      uint64_t gfn = gpa >> AMDVI_PAGE_SHIFT_4K;
>
>      /* don't cache erroneous translations */
> @@ -1135,6 +1135,7 @@ static void amdvi_reset(DeviceState *dev)
>
>  static void amdvi_realize(DeviceState *dev, Error **err)
>  {
> +    int ret = 0;
>      AMDVIState *s = AMD_IOMMU_DEVICE(dev);
>      X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
>      PCIBus *bus = PC_MACHINE(qdev_get_machine())->bus;
> @@ -1147,8 +1148,11 @@ static void amdvi_realize(DeviceState *dev, Error **err)
>      object_property_set_bool(OBJECT(&s->pci), true, "realized", err);
>      s->capab_offset = pci_add_capability(&s->pci.dev, AMDVI_CAPAB_ID_SEC, 0,
>                                           AMDVI_CAPAB_SIZE);
> -    pci_add_capability(&s->pci.dev, PCI_CAP_ID_MSI, 0, AMDVI_CAPAB_REG_SIZE);
> +    assert(s->capab_offset > 0);
> +    ret = pci_add_capability(&s->pci.dev, PCI_CAP_ID_MSI, 0, 
> AMDVI_CAPAB_REG_SIZE);
> +    assert(ret > 0);
>      pci_add_capability(&s->pci.dev, PCI_CAP_ID_HT, 0, AMDVI_CAPAB_REG_SIZE);

Did you forget to assign the result to ret here? Without that, the 
following assertion does not make sense, and coverity will still complain.

> +    assert(ret > 0);
>
>      /* set up MMIO */
>      memory_region_init_io(&s->mmio, OBJECT(s), &mmio_mem_ops, s, "amdvi-mmio",

Stefan