[PATCH 5.7 077/112] nvme: fix identify error status silent ignore

Greg Kroah-Hartman
2020-07-07T15:25:36Z

From: Sagi Grimberg <sagi@grimberg.me>

[ Upstream commit ea43d9709f727e728e933a8157a7a7ca1a868281 ]

Commit 59c7c3caaaf8 intended to only silently ignore non retry-able
errors (DNR bit set) such that we can still identify misbehaving
controllers, and in the other hand propagate retry-able errors (DNR bit
cleared) so we don't wrongly abandon a namespace just because it happens
to be temporarily inaccessible.

The goal remains the same as the original commit where this was
introduced but unfortunately had the logic backwards.

Fixes: 59c7c3caaaf8 ("nvme: fix possible hang when ns scanning fails during error recovery")
Reported-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/nvme/host/core.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 85ce6c682849e..71d63ed62071e 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1120,10 +1120,16 @@ static int nvme_identify_ns_descs(struct nvme_ctrl *ctrl, unsigned nsid,
dev_warn(ctrl->device,
"Identify Descriptors failed (%d)\n", status);
/*
- * Don't treat an error as fatal, as we potentially already
- * have a NGUID or EUI-64.
+ * Don't treat non-retryable errors as fatal, as we potentially
+ * already have a NGUID or EUI-64. If we failed with DNR set,
+ * we want to silently ignore the error as we can still
+ * identify the device, but if the status has DNR set, we want
+ * to propagate the error back specifically for the disk
+ * revalidation flow to make sure we don't abandon the
+ * device just because of a temporal retry-able error (such
+ * as path of transport errors).
*/
- if (status > 0 && !(status & NVME_SC_DNR))
+ if (status > 0 && (status & NVME_SC_DNR))
status = 0;
goto free_data;
}
--
2.25.1