Hi Robin, On Fri, Feb 28, 2020 at 02:18:55PM +0000, Robin Murphy wrote: > Since we ony support the TTB1 quirk for AArch64 contexts, and > consequently only for 64-bit builds, the sign-extension aspect of the > "are all bits above IAS consistent?" check should implicitly only apply > to 64-bit IOVAs. Change the type of the cast to ensure that 32-bit longs > don't inadvertently get sign-extended, and thus considered invalid, if > they happen to be above 2GB in the TTB0 region. > > Reported-by: Stephan Gerhold <step...@gerhold.net> > Signed-off-by: Robin Murphy <robin.mur...@arm.com> >
Thanks for the patch! Just wanted to report that this patch does indeed fix the problem I had with qcom-venus on ARM32. It's probably too late now, but FWIW: Tested-by: Stephan Gerhold <step...@gerhold.net> > --- > > Logically there may also have been a UBSAN "shift greater than size of > type" warning too, but arch/arm doesn't support UBSAN_SANITIZE_ALL, > and that's now my only easy "spin up a 32-bit VM" option to hand :) > > drivers/iommu/io-pgtable-arm.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c > index 983b08477e64..04fbd4bf0ff9 100644 > --- a/drivers/iommu/io-pgtable-arm.c > +++ b/drivers/iommu/io-pgtable-arm.c > @@ -468,7 +468,7 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, > unsigned long iova, > arm_lpae_iopte *ptep = data->pgd; > int ret, lvl = data->start_level; > arm_lpae_iopte prot; > - long iaext = (long)iova >> cfg->ias; > + long iaext = (s64)iova >> cfg->ias; > > /* If no access, then nothing to do */ > if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE))) > @@ -645,7 +645,7 @@ static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, > unsigned long iova, > struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops); > struct io_pgtable_cfg *cfg = &data->iop.cfg; > arm_lpae_iopte *ptep = data->pgd; > - long iaext = (long)iova >> cfg->ias; > + long iaext = (s64)iova >> cfg->ias; > > if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size)) > return 0; > -- > 2.23.0.dirty > _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
