This patch set addresses two issues in arch/arm/mach-hisi/hotplug.c
1) The hisi hotplug functions were using a few unchecked
of_iomap() while at the same time the system relied on
those mappings. Checks for !NULL were inserted.
2) Further some mandatory of_node_put() were missing and have
been inserted.
of_iomap() can return NULL which seems critical here and thus should be
explicitly flagged so that the cause of system halting can be understood.
As of_find_compatible_node() is returning a device node with refcount
incremented it must be explicitly decremented here.
Signed-off-by: Nicholas Mc Guire <[email protected]>
Fixes: commit 7fda91e73155 ("ARM: hisi: enable smp for HiP01")
---
Problem located by experimental coccinelle script
Patch was compile tested with: hisi_defconfig (implies CONFIG_SMP=y)
There are two change related checkpatch warnings about
"WARNING: Avoid crashing the kernel - try using WARN_ON"
but here the BUG_ON() seems adequate.
Patch is against 4.18-rc3 (localversion-next is next-20180712)
arch/arm/mach-hisi/hotplug.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm/mach-hisi/hotplug.c b/arch/arm/mach-hisi/hotplug.c
index a129aae..3b0d1c6 100644
--- a/arch/arm/mach-hisi/hotplug.c
+++ b/arch/arm/mach-hisi/hotplug.c
@@ -219,10 +219,10 @@ void hip01_set_cpu(int cpu, bool enable)
if (!ctrl_base) {
np = of_find_compatible_node(NULL, NULL, "hisilicon,hip01-sysctrl");
- if (np)
- ctrl_base = of_iomap(np, 0);
- else
- BUG();
+ BUG_ON(!np);
+ ctrl_base = of_iomap(np, 0);
+ of_node_put(np);
+ BUG_ON(!ctrl_base);
}
if (enable) {
--
2.1.4
Relying on an unchecked of_iomap() which can return NULL is problematic
here, an explicit check seems mandatory. Also the call to
of_find_compatible_node() returns a device node with refcount incremented
therefor an explicit of_node_put() is needed here.
Signed-off-by: Nicholas Mc Guire <[email protected]>
Fixes: commit 22bae4290457 ("ARM: hi3xxx: add hotplug support")
---
Problem found by an experimental coccinelle script
The way id is used is a bit redundant with the function return - not
really clear if this "double indication" is intentional or just happened ?
Also note that hi3xxx_hotplug_init probably should be bool as that is how
it is being used - the error return is not actually interpreted beyond
detection of failure in its only call site hi3xxx_set_cpu().
Patch was compile tested with: hisi_defconfig (implies CONFIG_SMP=y)
Patch is against 4.18-rc3 (localversion-next is next-20180712)
arch/arm/mach-hisi/hotplug.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/arch/arm/mach-hisi/hotplug.c b/arch/arm/mach-hisi/hotplug.c
index 40857bf..4036ffe 100644
--- a/arch/arm/mach-hisi/hotplug.c
+++ b/arch/arm/mach-hisi/hotplug.c
@@ -148,13 +148,20 @@ static int hi3xxx_hotplug_init(void)
struct device_node *node;
node = of_find_compatible_node(NULL, NULL, "hisilicon,sysctrl");
- if (node) {
- ctrl_base = of_iomap(node, 0);
- id = HI3620_CTRL;
- return 0;
+ if (!node) {
+ id = ERROR_CTRL;
+ return -ENOENT;
}
- id = ERROR_CTRL;
- return -ENOENT;
+
+ ctrl_base = of_iomap(node, 0);
+ of_node_put(node);
+ if (!ctrl_base) {
+ id = ERROR_CTRL;
+ return -ENOMEM;
+ }
+
+ id = HI3620_CTRL;
+ return 0;
}
void hi3xxx_set_cpu(int cpu, bool enable)
--
2.1.4
of_find_compatible_node() returns a device node with refcount incremented
and thus needs an explicit of_node_put(). Further relying on an unchecked
of_iomap() which can return NULL is problematic here, after all ctrl_base
is critical enough for hix5hd2_set_cpu() to call BUG() if not available
so a check seems mandated here.
Signed-off-by: Nicholas Mc Guire <[email protected]>
0002 Fixes: commit 06cc5c1d4d73 ("ARM: hisi: enable hix5hd2 SoC")
---
Problem found by an experimental coccinelle script
Patch was compile tested with: hisi_defconfig (implies CONFIG_SMP=y)
Patch is against 4.18-rc3 (localversion-next is next-20180712)
arch/arm/mach-hisi/hotplug.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/arch/arm/mach-hisi/hotplug.c b/arch/arm/mach-hisi/hotplug.c
index 3b0d1c6..40857bf 100644
--- a/arch/arm/mach-hisi/hotplug.c
+++ b/arch/arm/mach-hisi/hotplug.c
@@ -173,11 +173,15 @@ static bool hix5hd2_hotplug_init(void)
struct device_node *np;
np = of_find_compatible_node(NULL, NULL, "hisilicon,cpuctrl");
- if (np) {
- ctrl_base = of_iomap(np, 0);
- return true;
- }
- return false;
+ if (!np)
+ return false;
+
+ ctrl_base = of_iomap(np, 0);
+ of_node_put(np);
+ if (!ctrl_base)
+ return false;
+
+ return true;
}
void hix5hd2_set_cpu(int cpu, bool enable)
--
2.1.4
Hi Nicholas,
On 2018/7/12 10:28, Nicholas Mc Guire wrote:
> This patch set addresses two issues in arch/arm/mach-hisi/hotplug.c
>
> 1) The hisi hotplug functions were using a few unchecked
> of_iomap() while at the same time the system relied on
> those mappings. Checks for !NULL were inserted.
>
> 2) Further some mandatory of_node_put() were missing and have
> been inserted.
>
>
> .
>
Thanks!
Applied all the 3 patches to the hisilicon SoC tree.
Best Regards,
Wei