Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 681cc360 authored by Bart Van Assche's avatar Bart Van Assche Committed by Doug Ledford
Browse files

IB/srp: Fix infinite loop when FMR sg[0].offset != 0 



Avoid that mapping an sg-list in which the first element has a
non-zero offset triggers an infinite loop when using FMR. This
patch makes the FMR mapping code similar to that of ib_sg_to_pages().

Note: older Mellanox HCAs do not support non-zero offsets for FMR.
See also commit 8c4037b5 ("IB/srp: always avoid non-zero offsets
into an FMR").

Reported-by: default avatarAlex Estrin <alex.estrin@intel.com>
Signed-off-by: default avatarBart Van Assche <bart.vanassche@sandisk.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
parent 52bb8c62

drivers/infiniband/ulp/srp/ib_srp.c

+5 −3
Original line number Diff line number Diff line
@@ -1402,7 +1402,9 @@ static int srp_map_sg_entry(struct srp_map_state *state, 


	while (dma_len) {

		unsigned offset = dma_addr & ~dev->mr_page_mask;

		if (state->npages == dev->max_pages_per_mr || offset != 0) {



		if (state->npages == dev->max_pages_per_mr ||

		    (state->npages > 0 && offset != 0)) {

			ret = srp_map_finish_fmr(state, ch);

			if (ret)

				return ret;
@@ -1419,12 +1421,12 @@ static int srp_map_sg_entry(struct srp_map_state *state, 
	}



	/*

	 * If the last entry of the MR wasn't a full page, then we need to

	 * If the end of the MR is not on a page boundary then we need to

	 * close it out and start a new one -- we can only merge at page

	 * boundaries.

	 */

	ret = 0;

	if (len != dev->mr_page_size)

	if ((dma_addr & ~dev->mr_page_mask) != 0)

		ret = srp_map_finish_fmr(state, ch);

	return ret;

}