On 2/10/23 03:03, Andrew Donnellan wrote:
From: Russell Currey <rus...@russell.cc>
The secvar code only supports one consumer at a time.
Multiple consumers aren't possible at this point in time, but we'd want
it to be obvious if it ever could happen.
Signed-off-by: Russell Currey <rus...@russell.cc>
Co-developed-by: Andrew Donnellan <a...@linux.ibm.com>
Signed-off-by: Andrew Donnellan <a...@linux.ibm.com>
---
v4: Return an error and don't actually try to set secvar_operations if the
warning is triggered (npiggin)
v5: Drop "extern" to fix a checkpatch check (snowpatch)
v6: Return -EBUSY rather than -1 (stefanb)
---
arch/powerpc/include/asm/secvar.h | 4 ++--
arch/powerpc/kernel/secvar-ops.c | 10 ++++++++--
arch/powerpc/platforms/powernv/opal-secvar.c | 4 +---
3 files changed, 11 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/include/asm/secvar.h
b/arch/powerpc/include/asm/secvar.h
index 07ba36f868a7..a2b5f2203dc5 100644
--- a/arch/powerpc/include/asm/secvar.h
+++ b/arch/powerpc/include/asm/secvar.h
@@ -21,11 +21,11 @@ struct secvar_operations {
#ifdef CONFIG_PPC_SECURE_BOOT
-extern void set_secvar_ops(const struct secvar_operations *ops);
+int set_secvar_ops(const struct secvar_operations *ops);
#else
-static inline void set_secvar_ops(const struct secvar_operations *ops) { }
+static inline int set_secvar_ops(const struct secvar_operations *ops) { return
0; }
#endif
diff --git a/arch/powerpc/kernel/secvar-ops.c b/arch/powerpc/kernel/secvar-ops.c
index 6a29777d6a2d..19172a2804f0 100644
--- a/arch/powerpc/kernel/secvar-ops.c
+++ b/arch/powerpc/kernel/secvar-ops.c
@@ -8,10 +8,16 @@
#include <linux/cache.h>
#include <asm/secvar.h>
+#include <asm/bug.h>
-const struct secvar_operations *secvar_ops __ro_after_init;
+const struct secvar_operations *secvar_ops __ro_after_init = NULL;
-void set_secvar_ops(const struct secvar_operations *ops)
+int set_secvar_ops(const struct secvar_operations *ops)
{
+ if (WARN_ON_ONCE(secvar_ops))
+ return -EBUSY;
+
secvar_ops = ops;
+
+ return 0;
}
diff --git a/arch/powerpc/platforms/powernv/opal-secvar.c
b/arch/powerpc/platforms/powernv/opal-secvar.c
index ef89861569e0..4c0a3b030fe0 100644
--- a/arch/powerpc/platforms/powernv/opal-secvar.c
+++ b/arch/powerpc/platforms/powernv/opal-secvar.c
@@ -113,9 +113,7 @@ static int opal_secvar_probe(struct platform_device *pdev)
return -ENODEV;
}
- set_secvar_ops(&opal_secvar_ops);
-
- return 0;
+ return set_secvar_ops(&opal_secvar_ops);
}
static const struct of_device_id opal_secvar_match[] = {
Reviewed-by: Stefan Berger <stef...@linux.ibm.com>
