This is a note to let you know that I've just added the patch titled

    of/address: Return an error when no valid dma-ranges are found

to the 5.10-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:
     of-address-return-an-error-when-no-valid-dma-ranges-are-found.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <sta...@vger.kernel.org> know about it.


>From f6933c01e42d2fc83b9133ed755609e4aac6eadd Mon Sep 17 00:00:00 2001
From: Mark Brown <broo...@kernel.org>
Date: Sat, 28 Jan 2023 17:47:50 +0000
Subject: of/address: Return an error when no valid dma-ranges are found

From: Mark Brown <broo...@kernel.org>

commit f6933c01e42d2fc83b9133ed755609e4aac6eadd upstream.

Commit 7a8b64d17e35 ("of/address: use range parser for of_dma_get_range")
converted the parsing of dma-range properties to use code shared with the
PCI range parser. The intent was to introduce no functional changes however
in the case where we fail to translate the first resource instead of
returning -EINVAL the new code we return 0. Restore the previous behaviour
by returning an error if we find no valid ranges, the original code only
handled the first range but subsequently support for parsing all supplied
ranges was added.

This avoids confusing code using the parsed ranges which doesn't expect to
successfully parse ranges but have only a list terminator returned, this
fixes breakage with so far as I can tell all DMA for on SoC devices on the
Socionext Synquacer platform which has a firmware supplied DT. A bisect
identified the original conversion as triggering the issues there.

Fixes: 7a8b64d17e35 ("of/address: use range parser for of_dma_get_range")
Signed-off-by: Mark Brown <broo...@kernel.org>
Cc: Luca Di Stefano <luca.distef...@linaro.org>
Cc: 993...@bugs.debian.org
Cc: sta...@kernel.org
Link: 
https://lore.kernel.org/r/20230126-synquacer-boot-v2-1-cb80fd23c...@kernel.org
Signed-off-by: Rob Herring <r...@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/of/address.c |   21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -990,8 +990,19 @@ int of_dma_get_range(struct device_node
        }
 
        of_dma_range_parser_init(&parser, node);
-       for_each_of_range(&parser, &range)
+       for_each_of_range(&parser, &range) {
+               if (range.cpu_addr == OF_BAD_ADDR) {
+                       pr_err("translation of DMA address(%llx) to CPU address 
failed node(%pOF)\n",
+                              range.bus_addr, node);
+                       continue;
+               }
                num_ranges++;
+       }
+
+       if (!num_ranges) {
+               ret = -EINVAL;
+               goto out;
+       }
 
        r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
        if (!r) {
@@ -1000,18 +1011,16 @@ int of_dma_get_range(struct device_node
        }
 
        /*
-        * Record all info in the generic DMA ranges array for struct device.
+        * Record all info in the generic DMA ranges array for struct device,
+        * returning an error if we don't find any parsable ranges.
         */
        *map = r;
        of_dma_range_parser_init(&parser, node);
        for_each_of_range(&parser, &range) {
                pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
                         range.bus_addr, range.cpu_addr, range.size);
-               if (range.cpu_addr == OF_BAD_ADDR) {
-                       pr_err("translation of DMA address(%llx) to CPU address 
failed node(%pOF)\n",
-                              range.bus_addr, node);
+               if (range.cpu_addr == OF_BAD_ADDR)
                        continue;
-               }
                r->cpu_start = range.cpu_addr;
                r->dma_start = range.bus_addr;
                r->size = range.size;


Patches currently in stable-queue which might be from broo...@kernel.org are

queue-5.10/of-address-return-an-error-when-no-valid-dma-ranges-are-found.patch

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