From: Gaurav Batra gbatra@linux.vnet.ibm.com
commit 1f7aacc5eb9ed2cc17be7a90da5cd559effb9d59 upstream.
For an SR-IOV device, while enabling DDW, a new table is created and added at index 1 in the group. In the below 2 scenarios, the table is incorrectly referenced at index 0 (which is where the table is for default DMA window).
1. When adding DDW
This issue is exposed with "slub_debug". Error thrown out from dma_iommu_dma_supported()
Warning: IOMMU offset too big for device mask mask: 0xffffffff, table offset: 0x800000000000000
2. During Dynamic removal of the PCI device.
Error is from iommu_tce_table_put() since a NULL table pointer is passed in.
Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping") Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Gaurav Batra gbatra@linux.vnet.ibm.com Reviewed-by: Brian King brking@linux.vnet.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://msgid.link/20230505184701.91613-1-gbatra@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/kernel/dma-iommu.c | 4 +++- arch/powerpc/platforms/pseries/iommu.c | 13 +++++++++---- 2 files changed, 12 insertions(+), 5 deletions(-)
--- a/arch/powerpc/kernel/dma-iommu.c +++ b/arch/powerpc/kernel/dma-iommu.c @@ -144,7 +144,7 @@ static bool dma_iommu_bypass_supported(s /* We support DMA to/from any memory page via the iommu */ int dma_iommu_dma_supported(struct device *dev, u64 mask) { - struct iommu_table *tbl = get_iommu_table_base(dev); + struct iommu_table *tbl;
if (dev_is_pci(dev) && dma_iommu_bypass_supported(dev, mask)) { /* @@ -162,6 +162,8 @@ int dma_iommu_dma_supported(struct devic return 1; }
+ tbl = get_iommu_table_base(dev); + if (!tbl) { dev_err(dev, "Warning: IOMMU dma not supported: mask 0x%08llx, table unavailable\n", mask); return 0; --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -85,19 +85,24 @@ static struct iommu_table_group *iommu_p static void iommu_pseries_free_group(struct iommu_table_group *table_group, const char *node_name) { - struct iommu_table *tbl; - if (!table_group) return;
- tbl = table_group->tables[0]; #ifdef CONFIG_IOMMU_API if (table_group->group) { iommu_group_put(table_group->group); BUG_ON(table_group->group); } #endif - iommu_tce_table_put(tbl); + + /* Default DMA window table is at index 0, while DDW at 1. SR-IOV + * adapters only have table on index 1. + */ + if (table_group->tables[0]) + iommu_tce_table_put(table_group->tables[0]); + + if (table_group->tables[1]) + iommu_tce_table_put(table_group->tables[1]);
kfree(table_group); }