[PATCH] powerpc/xive: Fix compile when !CONFIG_PPC_POWERNV.

[PATCH] powerpc/xive: Fix compile when !CONFIG_PPC_POWERNV.

[Cédric Le Goater]

The automatic "save & restore" of interrupt context is a POWER10/XIVE2
feature exploited by KVM under the PowerNV platform. It is not
available under pSeries and the associated toggle should not be
exposed under the XIVE debugfs directory.

Introduce a platform handler for debugfs initialization and move the
'save-restore' entry under the native (PowerNV) backend to fix compile
when !CONFIG_PPC_POWERNV.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 1e7684dc4fc7 ("powerpc/xive: Add a debugfs toggle for save-restore")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 arch/powerpc/sysdev/xive/xive-internal.h |  1 +
 arch/powerpc/sysdev/xive/common.c        |  4 +++-
 arch/powerpc/sysdev/xive/native.c        | 11 +++++++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/sysdev/xive/xive-internal.h b/arch/powerpc/sysdev/xive/xive-internal.h
index e0941bc64430..fe6d95d54af9 100644
--- a/arch/powerpc/sysdev/xive/xive-internal.h
+++ b/arch/powerpc/sysdev/xive/xive-internal.h
@@ -58,6 +58,7 @@ struct xive_ops {
 	void	(*put_ipi)(unsigned int cpu, struct xive_cpu *xc);
 #endif
 	int	(*debug_show)(struct seq_file *m, void *private);
+	int	(*debug_create)(struct dentry *xive_dir);
 	const char *name;
 };
 
diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index 43f7f7df6407..1ca5564bda9d 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -1847,7 +1847,9 @@ static void xive_core_debugfs_create(void)
 				    &xive_eq_debug_fops);
 	}
 	debugfs_create_bool("store-eoi", 0600, xive_dir, &xive_store_eoi);
-	debugfs_create_bool("save-restore", 0600, xive_dir, &xive_has_save_restore);
+
+	if (xive_ops->debug_create)
+		xive_ops->debug_create(xive_dir);
 }
 #else
 static inline void xive_core_debugfs_create(void) { }
diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c
index d6a091dc1bce..d4243dab230e 100644
--- a/arch/powerpc/sysdev/xive/native.c
+++ b/arch/powerpc/sysdev/xive/native.c
@@ -461,6 +461,14 @@ void xive_native_sync_queue(u32 hw_irq)
 }
 EXPORT_SYMBOL_GPL(xive_native_sync_queue);
 
+#ifdef CONFIG_DEBUG_FS
+static int xive_native_debug_create(struct dentry *xive_dir)
+{
+	debugfs_create_bool("save-restore", 0600, xive_dir, &xive_has_save_restore);
+	return 0;
+}
+#endif
+
 static const struct xive_ops xive_native_ops = {
 	.populate_irq_data	= xive_native_populate_irq_data,
 	.configure_irq		= xive_native_configure_irq,
@@ -478,6 +486,9 @@ static const struct xive_ops xive_native_ops = {
 	.get_ipi		= xive_native_get_ipi,
 	.put_ipi		= xive_native_put_ipi,
 #endif /* CONFIG_SMP */
+#ifdef CONFIG_DEBUG_FS
+	.debug_create		= xive_native_debug_create,
+#endif /* CONFIG_DEBUG_FS */
 	.name			= "native",
 };
 
-- 
2.31.1

Re: [PATCH] powerpc/xive: Fix compile when !CONFIG_PPC_POWERNV.

[Michael Ellerman]

On Wed, 1 Dec 2021 17:54:18 +0100, Cédric Le Goater wrote:
> The automatic "save & restore" of interrupt context is a POWER10/XIVE2
> feature exploited by KVM under the PowerNV platform. It is not
> available under pSeries and the associated toggle should not be
> exposed under the XIVE debugfs directory.
> 
> Introduce a platform handler for debugfs initialization and move the
> 'save-restore' entry under the native (PowerNV) backend to fix compile
> when !CONFIG_PPC_POWERNV.
> 
> [...]

Applied to powerpc/next.

[1/1] powerpc/xive: Fix compile when !CONFIG_PPC_POWERNV.
      https://git.kernel.org/powerpc/c/2a2ac8a7018b953cd23d770ebd28f8e1ea365df4

cheers