Subject: Re: [PATCH for-rc] Revert "RDMA/efa: Use API to get contiguous memory blocks aligned to device supported page size"
On 20/01/2020 16:10, Gal Pressman wrote:
The cited commit leads to register MR failures and random hangs when running different MPI applications. The exact root cause for the issue is still not clear, this revert brings us back to a stable state.
This reverts commit 40ddb3f020834f9afb7aab31385994811f4db259.
Fixes: 40ddb3f02083 ("RDMA/efa: Use API to get contiguous memory blocks aligned to device supported page size") Cc: Shiraz Saleem shiraz.saleem@intel.com Cc: stable@vger.kernel.org # 5.3 Signed-off-by: Gal Pressman galpress@amazon.com
Shiraz, I think I found the root cause here. I'm noticing a register MR of size 32k, which is constructed from two sges, the first sge of size 12k and the second of 20k.
ib_umem_find_best_pgsz returns page shift 13 in the following way:
0x103dcb2000 0x103dcb5000 0x103dd5d000 0x103dd62000 +----------+ +------------------+ | | | | | 12k | | 20k | +----------+ +------------------+
+------+------+ +------+------+------+ | | | | | | | | 8k | 8k | | 8k | 8k | 8k | +------+------+ +------+------+------+0x103dcb2000 0x103dcb6000 0x103dd5c000 0x103dd62000
Gal - would be useful to know the IOVA (virt) and umem->addr also for this MR in ib_umem_find_best_pgsz