This is a note to let you know that I've just added the patch titled ntb: transport shouldn't disable link due to bogus values in SPADs to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ntb-transport-shouldn-t-disable-link-due-to-bogus-values-in-spads.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From f3fd2afed8eee91620d05b69ab94c14793c849d7 Mon Sep 17 00:00:00 2001 From: Dave Jiang <dave.jiang@xxxxxxxxx> Date: Fri, 28 Jul 2017 15:10:48 -0700 Subject: ntb: transport shouldn't disable link due to bogus values in SPADs From: Dave Jiang <dave.jiang@xxxxxxxxx> commit f3fd2afed8eee91620d05b69ab94c14793c849d7 upstream. It seems that under certain scenarios the SPAD can have bogus values caused by an agent (i.e. BIOS or other software) that is not the kernel driver, and that causes memory window setup failure. This should not cause the link to be disabled because if we do that, the driver will never recover again. We have verified in testing that this issue happens and prevents proper link recovery. Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx> Acked-by: Allen Hubbe <Allen.Hubbe@xxxxxxxx> Signed-off-by: Jon Mason <jdmason@xxxxxxxx> Fixes: 84f766855f61 ("ntb: stop link work when we do not have memory") Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/ntb/ntb_transport.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -921,10 +921,8 @@ out1: ntb_free_mw(nt, i); /* if there's an actual failure, we should just bail */ - if (rc < 0) { - ntb_link_disable(ndev); + if (rc < 0) return; - } out: if (ntb_link_is_up(ndev, NULL, NULL) == 1) Patches currently in stable-queue which might be from dave.jiang@xxxxxxxxx are queue-4.9/ntb-no-sleep-in-ntb_async_tx_submit.patch queue-4.9/ntb-transport-shouldn-t-disable-link-due-to-bogus-values-in-spads.patch