[PATCH v3] x86/msi: Fix compile error caused by GENERIC_MSI_IRQ and X86_LOCAL_APIC

From: Lu Yao
Date: Wed Oct 11 2023 - 23:27:21 EST


When compiling the x86 kernel, if X86_LOCAL_APIC is not enabled but
GENERIC_MSI_IRQ is selected in '.config', the following compilation
error will occur:

include/linux/gpio/driver.h:38:19: error:
field 'msiinfo' has incomplete type

kernel/irq/msi.c:752:5: error: invalid use of incomplete typedef
'msi_alloc_info_t' {aka 'struct irq_alloc_info'}

kernel/irq/msi.c:740:1: error: control reaches end of non-void function

This is because file such as 'kernel/irq/msi.c' only depends on
'GENERIC_MSI_IRQ', and uses 'struct msi_alloc_info_t'. However,
this struct depends on 'X86_LOCAL_APIC'.

When enable 'GENERIC_MSI_IRQ' or 'X86_LOCAL_APIC' will select
'IRQ_DOMAIN_HIERARCHY', so exposing this struct using
'IRQ_DOMAIN_HIERARCHY' rather than 'X86_LOCAL_APIC'.

Under the above conditions, if 'HPET_TIMER' is selected, the following
compilation error will occur:

arch/x86/kernel/hpet.c:550:13: error: ‘x86_vector_domain’ undeclared

arch/x86/kernel/hpet.c:600:9: error: implicit declaration of
function ‘init_irq_alloc_info’

This is because 'x86_vector_domain' is defined in 'kernel/apic/vector.c'
which is compiled only when 'X86_LOCAL_APIC' is enabled. Besides,
function 'msi_domain_set_affinity' is defined in 'include/linux/msi.h'
which depends on 'GENERIC_MSI_IRQ'. So use 'X86_LOCAL_APIC' and
'GENERIC_MSI_IRQ' to expose these code.

Tested-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Signed-off-by: Lu Yao <yaolu@xxxxxxxxxx>
---
Change from v2:
* Fix arch/x86/kernel/hpet.c compiled error when enable 'X86_LOCAL_APIC'
'HPET_TIMER' but disable 'GENERIC_MSI_IRQ'.
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202310120849.zrfrI44Z-lkp@xxxxxxxxx/
v2: https://patchew.org/linux/20231011055749.98840-1-yaolu@xxxxxxxxxx/

Change from v1:
* Fix arch/x86/kernel/hpet.c compiled error when enable 'X86_LOCAL_APIC'
'GENERIC_MSI_IRQ' 'HPET_TIMER'
Thanks to Randy for the feedback.
v1: https://lore.kernel.org/lkml/20231008082827.279154-1-yaolu@xxxxxxxxxx/

---
arch/x86/include/asm/hw_irq.h | 6 +++---
arch/x86/kernel/hpet.c | 4 ++--
2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index 551829884734..b02c3cd3c0f6 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -28,7 +28,7 @@
#include <asm/irq.h>
#include <asm/sections.h>

-#ifdef CONFIG_X86_LOCAL_APIC
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
struct irq_data;
struct pci_dev;
struct msi_desc;
@@ -105,10 +105,10 @@ static inline void irq_complete_move(struct irq_cfg *c) { }
#endif

extern void apic_ack_edge(struct irq_data *data);
-#else /* CONFIG_X86_LOCAL_APIC */
+#else /* CONFIG_IRQ_DOMAIN_HIERARCHY */
static inline void lock_vector_lock(void) {}
static inline void unlock_vector_lock(void) {}
-#endif /* CONFIG_X86_LOCAL_APIC */
+#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */

/* Statistics */
extern atomic_t irq_err_count;
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index 1648aa0204d9..41eecf180b7f 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -52,7 +52,7 @@ unsigned long hpet_address;
u8 hpet_blockid; /* OS timer block num */
bool hpet_msi_disable;

-#ifdef CONFIG_GENERIC_MSI_IRQ
+#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_GENERIC_MSI_IRQ)
static DEFINE_PER_CPU(struct hpet_channel *, cpu_hpet_channel);
static struct irq_domain *hpet_domain;
#endif
@@ -469,7 +469,7 @@ static void __init hpet_legacy_clockevent_register(struct hpet_channel *hc)
/*
* HPET MSI Support
*/
-#ifdef CONFIG_GENERIC_MSI_IRQ
+#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_GENERIC_MSI_IRQ)
static void hpet_msi_unmask(struct irq_data *data)
{
struct hpet_channel *hc = irq_data_get_irq_handler_data(data);
--
2.25.1