diff options
| author | Gerd Rausch <gerd.rausch@oracle.com> | 2021-08-17 10:04:37 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-08-18 15:35:50 -0700 |
| commit | fb4b1373dcab086d0619c29310f0466a0b2ceb8a (patch) | |
| tree | 0a8689b6c5ad58ba5fc7dcaa608d24b66cba51d3 | |
| parent | c1930148a3941f891ddbd76fceaa4e10a957ccf2 (diff) | |
net/rds: dma_map_sg is entitled to merge entries
Function "dma_map_sg" is entitled to merge adjacent entries
and return a value smaller than what was passed as "nents".
Subsequently "ib_map_mr_sg" needs to work with this value ("sg_dma_len")
rather than the original "nents" parameter ("sg_len").
This old RDS bug was exposed and reliably causes kernel panics
(using RDMA operations "rds-stress -D") on x86_64 starting with:
commit c588072bba6b ("iommu/vt-d: Convert intel iommu driver to the iommu ops")
Simply put: Linux 5.11 and later.
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Link: https://lore.kernel.org/r/60efc69f-1f35-529d-a7ef-da0549cad143@oracle.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/rds/ib_frmr.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/rds/ib_frmr.c b/net/rds/ib_frmr.c index 9b6ffff72f2d..28c1b0022178 100644 --- a/net/rds/ib_frmr.c +++ b/net/rds/ib_frmr.c @@ -131,9 +131,9 @@ static int rds_ib_post_reg_frmr(struct rds_ib_mr *ibmr) cpu_relax(); } - ret = ib_map_mr_sg_zbva(frmr->mr, ibmr->sg, ibmr->sg_len, + ret = ib_map_mr_sg_zbva(frmr->mr, ibmr->sg, ibmr->sg_dma_len, &off, PAGE_SIZE); - if (unlikely(ret != ibmr->sg_len)) + if (unlikely(ret != ibmr->sg_dma_len)) return ret < 0 ? ret : -EINVAL; if (cmpxchg(&frmr->fr_state, |