On Wed, 1 Jul 2020 09:45:40 +0800 Lu Baolu <baolu...@linux.intel.com> wrote:
> Hi Jacob, > > On 7/1/20 1:34 AM, Jacob Pan wrote: > > On Thu, 25 Jun 2020 18:10:43 +0800 > > Lu Baolu<baolu...@linux.intel.com> wrote: > > > >> Hi, > >> > >> On 2020/6/23 23:43, Jacob Pan wrote: > >>> For guest requested IOTLB invalidation, address and mask are > >>> provided as part of the invalidation data. VT-d HW silently > >>> ignores any address bits below the mask. SW shall also allow such > >>> case but give warning if address does not align with the mask. > >>> This patch relax the fault handling from error to warning and > >>> proceed with invalidation request with the given mask. > >>> > >>> Signed-off-by: Jacob Pan<jacob.jun....@linux.intel.com> > >>> --- > >>> drivers/iommu/intel/iommu.c | 7 +++---- > >>> 1 file changed, 3 insertions(+), 4 deletions(-) > >>> > >>> diff --git a/drivers/iommu/intel/iommu.c > >>> b/drivers/iommu/intel/iommu.c index 5ea5732d5ec4..50fc62413a35 > >>> 100644 --- a/drivers/iommu/intel/iommu.c > >>> +++ b/drivers/iommu/intel/iommu.c > >>> @@ -5439,13 +5439,12 @@ intel_iommu_sva_invalidate(struct > >>> iommu_domain *domain, struct device *dev, > >>> switch (BIT(cache_type)) { > >>> case IOMMU_CACHE_INV_TYPE_IOTLB: > >>> + /* HW will ignore LSB bits based on > >>> address mask */ if (inv_info->granularity == IOMMU_INV_GRANU_ADDR > >>> && size && > >>> (inv_info->addr_info.addr & > >>> ((BIT(VTD_PAGE_SHIFT + size)) - 1))) { > >>> - pr_err_ratelimited("Address out > >>> of range, 0x%llx, size order %llu\n", > >>> - > >>> inv_info->addr_info.addr, size); > >>> - ret = -ERANGE; > >>> - goto out_unlock; > >>> + WARN_ONCE(1, "Address out of > >>> range, 0x%llx, size order %llu\n", > >>> + > >>> inv_info->addr_info.addr, size); > >> I don't think WARN_ONCE() is suitable here. It makes users think > >> it's a kernel bug. How about pr_warn_ratelimited()? > >> > > I think pr_warn_ratelimited might still be too chatty. There is no > > functional issues, we just don't to silently ignore it. Perhaps just > > say: > > WARN_ONCE(1, "User provided address not page aligned, alignment > > forced") ? > > > > WARN() is normally used for reporting a kernel bug. It dumps kernel > trace. And the users will report bug through bugzilla.kernel.org. > > In this case, it's actually an unexpected user input, we shouldn't > treat it as a kernel bug and pr_err_ratelimited() is enough? > Sounds good. I will leave it. Thanks, Jacob > Best regards, > baolu [Jacob Pan] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu