On Tue, 15 Oct 2019 17:16:50 +0200 Joerg Roedel <joro@xxxxxxxxxx> wrote: > From: Joerg Roedel <jroedel@xxxxxxx> > > After enabling CONFIG_IOMMU_DMA on X86 a new warning appears when > compiling vfio: > > drivers/vfio/vfio_iommu_type1.c: In function ‘vfio_iommu_type1_attach_group’: > drivers/vfio/vfio_iommu_type1.c:1827:7: warning: ‘resv_msi_base’ may be used uninitialized in this function [-Wmaybe-uninitialized] > ret = iommu_get_msi_cookie(domain->domain, resv_msi_base); > ~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > The warning is a false positive, because the call to iommu_get_msi_cookie() > only happens when vfio_iommu_has_sw_msi() returned true. And that only > happens when it also set resv_msi_base. > > But initialize the variable anyway to get rid of the warning. > > Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> > --- > drivers/vfio/vfio_iommu_type1.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c > index 96fddc1dafc3..d864277ea16f 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -1658,7 +1658,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data, > struct bus_type *bus = NULL; > int ret; > bool resv_msi, msi_remap; > - phys_addr_t resv_msi_base; > + phys_addr_t resv_msi_base = 0; > struct iommu_domain_geometry geo; > LIST_HEAD(iova_copy); > LIST_HEAD(group_resv_regions); Thanks Joerg! Added to vfio for-linus branch with Connie and Eric's reviews for v5.4. Thanks, Alex