Andreas Färber <afaerber@xxxxxxx> writes:
> Am 19.01.2017 um 01:20 schrieb Andreas Färber:
>> Hi,
>>
>> Am 18.01.2017 um 17:50 schrieb Neil Armstrong:
>>> The Amlogic Meson GXBB/GXL/GXM secure monitor uses part of the memory space,
>>> this patch adds these reserved zones.
>>>
>>> Without such reserved memory zones, running the following stress command :
>>> $ stress-ng --vm 16 --vm-bytes 128M --timeout 10s
>>> multiple times:
>>>
>>> Could lead to the following kernel crashes :
>>> [ 46.937975] Bad mode in Error handler detected on CPU1, code 0xbf000000 -- SError
>>> ...
>>> [ 47.058536] Internal error: Attempting to execute userspace memory: 8600000f [#3] PREEMPT SMP
>>> ...
>>> Instead of the OOM killer.
>>>
>>
>> I miss a Fixes: or Cc: here for the backport you desired. To have it
>> fixed back to my very introduction:
>>
>> Fixes: 4f24eda8401f ("ARM64: dts: Prepare configs for Amlogic Meson GXBaby")
>>
>> People backporting it would need to handle the meson-{gx => gxbb}.dtsi
>> transition for 4.9 down to 4.6, which seems fairly straightforward.
>>
>>> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
>>> ---
>>> arch/arm64/boot/dts/amlogic/meson-gx.dtsi | 18 ++++++++++++++++++
>>> 1 file changed, 18 insertions(+)
>>>
>>> Changes since v4 at [5]:
>>> - Move start of ddr memory to reserved-memory node
>>> - Drop memory node move
>>> - Fix typo in sizes
>>>
>>> Changes since resent v2 at [4]:
>>> - Fix invalid comment of useable memory attributes
>>>
>>> Changes since original v2 at [3]:
>>> - Typo in commit 2GiB -> 1GiB, 4GiB -> 2GiB
>>>
>>> Changes since v2 at [2]:
>>> - Moved all memory node out of dtsi
>>> - Added comment about useable memory
>>> - Fixed comment about secmon reserved zone
>>>
>>> Changes since v1 at [1] :
>>> - Renamed reg into linux,usable-memory to ovveride u-boot memory
>>> - only kept secmon memory zone
>>>
>>> [1] http://lkml.kernel.org/r/20161212101801.28491-1-narmstrong@xxxxxxxxxxxx
>>> [2] http://lkml.kernel.org/r/1483105232-6242-1-git-send-email-narmstrong@xxxxxxxxxxxx
>>> [3] http://lkml.kernel.org/r/1484128128-22454-1-git-send-email-narmstrong@xxxxxxxxxxxx
>>> [4] http://lkml.kernel.org/r/1484128540-22662-1-git-send-email-narmstrong@xxxxxxxxxxxx
>>> [5] http://lkml.kernel.org/r/1484129414-23325-1-git-send-email-narmstrong@xxxxxxxxxxxx
>>>
>>> diff --git a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
>>> index eada0b5..63d52b7 100644
>>> --- a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
>>> +++ b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
>>> @@ -55,6 +55,24 @@
>>> #address-cells = <2>;
>>> #size-cells = <2>;
>>>
>>> + reserved-memory {
>>> + #address-cells = <2>;
>>> + #size-cells = <2>;
>>> + ranges;
>>> +
>>> + /* 16 MiB reserved for Hardware ROM Firmware */
>>> + hwrom: hwrom {
>>
>> Both sub-nodes get a label that is unused, but reserved-memory itself
>> does not (my v4 remark). Intentional?
>>
>>> + reg = <0x0 0x0 0x0 0x1000000>;
>>> + no-map;
>>> + };
>>> +
>>> + /* 2 MiB reserved for ARM Trusted Firmware (BL31) */
>>> + secmon: secmon {
>>
>> I note that this .dtsi further down has a node /firmware/secure-monitor
>> with label sm.
>> a) Is there any naming convention such as secmon_mem to adopt here to
>> avoid mixups with sm?
>> b) Should this secmon node be referenced in the secure-monitor node via
>> memory-node = <&secmon>; to model their connection, thereby giving the
>> label a use? Or should we maybe merge the two nodes by moving the
>> compatible string here?
>>
>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
>
> Answering my own question: the example labels use _reserved suffix.
>
>>> + reg = <0x0 0x10000000 0x0 0x200000>;
>
> And since we use a reg property here, the node name should get a unit
> address to avoid future dtc warnings/errors. Ditto for hwrom.
OK, I added Fixes:, your Reviewed-by, added the _reserved suffix and
unit address and applied to v4.10/fixes.
Update patch below for reference.
Other cleanups/fixups (like adding a phandle from secure monitor) can be
done as add-ons, as they are not strictly related to this fix.
Kevin
>From ecb88f3001ed9ee8c53450d971de8c18bcbf7925 Mon Sep 17 00:00:00 2001
From: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Date: Wed, 18 Jan 2017 17:50:45 +0100
Subject: [PATCH] ARM64: dts: meson-gx: Add firmware reserved memory zones
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The Amlogic Meson GXBB/GXL/GXM secure monitor uses part of the memory space,
this patch adds these reserved zones.
Without such reserved memory zones, running the following stress command :
$ stress-ng --vm 16 --vm-bytes 128M --timeout 10s
multiple times:
Could lead to the following kernel crashes :
[ 46.937975] Bad mode in Error handler detected on CPU1, code 0xbf000000 -- SError
...
[ 47.058536] Internal error: Attempting to execute userspace memory: 8600000f [#3] PREEMPT SMP
...
Instead of the OOM killer.
Fixes: 4f24eda8401f ("ARM64: dts: Prepare configs for Amlogic Meson GXBaby")
Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Reviewed-by: Andreas Färber <afaerber@xxxxxxx>
[khilman: added Fixes tag, added _reserved and unit addresses]
Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxxxx>
---
arch/arm64/boot/dts/amlogic/meson-gx.dtsi | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
index eada0b58ba1c..0cbe24b49710 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
@@ -55,6 +55,24 @@
#address-cells = <2>;
#size-cells = <2>;
+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+
+ /* 16 MiB reserved for Hardware ROM Firmware */
+ hwrom_reserved: hwrom@0 {
+ reg = <0x0 0x0 0x0 0x1000000>;
+ no-map;
+ };
+
+ /* 2 MiB reserved for ARM Trusted Firmware (BL31) */
+ secmon_reserved: secmon@10000000 {
+ reg = <0x0 0x10000000 0x0 0x200000>;
+ no-map;
+ };
+ };
+
cpus {
#address-cells = <0x2>;
#size-cells = <0x0>;
--
2.9.3
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