This is a note to let you know that I've just added the patch titled
cxl/region: Fix passthrough-decoder detection
to the 6.1-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:
cxl-region-fix-passthrough-decoder-detection.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 711442e29f16f0d39dd0e2460c9baacfccb9d5a7 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@xxxxxxxxx>
Date: Tue, 7 Feb 2023 11:04:30 -0800
Subject: cxl/region: Fix passthrough-decoder detection
From: Dan Williams <dan.j.williams@xxxxxxxxx>
commit 711442e29f16f0d39dd0e2460c9baacfccb9d5a7 upstream.
A passthrough decoder is a decoder that maps only 1 target. It is a
special case because it does not impose any constraints on the
interleave-math as compared to a decoder with multiple targets. Extend
the passthrough case to multi-target-capable decoders that only have one
target selected. I.e. the current code was only considering passthrough
*ports* which are only a subset of the potential passthrough decoder
scenarios.
Fixes: e4f6dfa9ef75 ("cxl/region: Fix 'distance' calculation with passthrough ports")
Cc: <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Link: https://lore.kernel.org/r/167564540422.847146.13816934143225777888.stgit@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/cxl/core/region.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 02275e6b621b..940f805b1534 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -993,10 +993,10 @@ static int cxl_port_setup_targets(struct cxl_port *port,
int i, distance;
/*
- * Passthrough ports impose no distance requirements between
+ * Passthrough decoders impose no distance requirements between
* peers
*/
- if (port->nr_dports == 1)
+ if (cxl_rr->nr_targets == 1)
distance = 0;
else
distance = p->nr_targets / cxl_rr->nr_targets;
--
2.39.1
Patches currently in stable-queue which might be from dan.j.williams@xxxxxxxxx are
queue-6.1/cxl-region-fix-passthrough-decoder-detection.patch
queue-6.1/nvdimm-support-sizeof-struct-page-max_struct_page_size.patch
queue-6.1/cxl-region-fix-null-pointer-dereference-for-resetting-decoder.patch
