2021-04-04 19:29:22

by Randy Dunlap

[permalink] [raw]
Subject: [PATCH v2] powerpc: iommu: fix build when neither PCI or IBMVIO is set

When neither CONFIG_PCI nor CONFIG_IBMVIO is set/enabled, iommu.c has a
build error. The fault injection code is not useful in that kernel config,
so make the FAIL_IOMMU option depend on PCI || IBMVIO.

Prevents this build error (warning escalated to error):
../arch/powerpc/kernel/iommu.c:178:30: error: 'fail_iommu_bus_notifier' defined but not used [-Werror=unused-variable]
178 | static struct notifier_block fail_iommu_bus_notifier = {

Fixes: d6b9a81b2a45 ("powerpc: IOMMU fault injection")
Signed-off-by: Randy Dunlap <[email protected]>
Reported-by: kernel test robot <[email protected]>
Suggested-by: Michael Ellerman <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: [email protected]
Cc: Anton Blanchard <[email protected]>
---
I was supposed to update this about one month ago, but then I lost
some email and also took a break for a few weeks, then I remembered,
so here it is.

arch/powerpc/Kconfig.debug | 1 +
1 file changed, 1 insertion(+)

--- lnx-512-rc1.orig/arch/powerpc/Kconfig.debug
+++ lnx-512-rc1/arch/powerpc/Kconfig.debug
@@ -353,6 +353,7 @@ config PPC_EARLY_DEBUG_CPM_ADDR
config FAIL_IOMMU
bool "Fault-injection capability for IOMMU"
depends on FAULT_INJECTION
+ depends on PCI || IBMVIO
help
Provide fault-injection capability for IOMMU. Each device can
be selectively enabled via the fail_iommu property.


2021-04-05 15:19:27

by Christophe Leroy

[permalink] [raw]
Subject: Re: [PATCH v2] powerpc: iommu: fix build when neither PCI or IBMVIO is set



Le 04/04/2021 à 21:26, Randy Dunlap a écrit :
> When neither CONFIG_PCI nor CONFIG_IBMVIO is set/enabled, iommu.c has a
> build error. The fault injection code is not useful in that kernel config,
> so make the FAIL_IOMMU option depend on PCI || IBMVIO.
>
> Prevents this build error (warning escalated to error):
> ../arch/powerpc/kernel/iommu.c:178:30: error: 'fail_iommu_bus_notifier' defined but not used [-Werror=unused-variable]
> 178 | static struct notifier_block fail_iommu_bus_notifier = {
>
> Fixes: d6b9a81b2a45 ("powerpc: IOMMU fault injection")
> Signed-off-by: Randy Dunlap <[email protected]>
> Reported-by: kernel test robot <[email protected]>
> Suggested-by: Michael Ellerman <[email protected]>
> Cc: Michael Ellerman <[email protected]>
> Cc: [email protected]
> Cc: Anton Blanchard <[email protected]>
> ---
> I was supposed to update this about one month ago, but then I lost
> some email and also took a break for a few weeks, then I remembered,
> so here it is.
>
> arch/powerpc/Kconfig.debug | 1 +
> 1 file changed, 1 insertion(+)

Wouldn't it be cleaner to get rid of those two horid #ifdefs ?
Of course we can do both.

diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 216871414434..d691afa8acf8 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -180,12 +180,10 @@ static struct notifier_block fail_iommu_bus_notifier = {

static int __init fail_iommu_setup(void)
{
-#ifdef CONFIG_PCI
- bus_register_notifier(&pci_bus_type, &fail_iommu_bus_notifier);
-#endif
-#ifdef CONFIG_IBMVIO
- bus_register_notifier(&vio_bus_type, &fail_iommu_bus_notifier);
-#endif
+ if (IS_ENABLED(CONFIG_PCI))
+ bus_register_notifier(&pci_bus_type, &fail_iommu_bus_notifier);
+ if (IS_ENABLED(CONFIG_IBMVIO))
+ bus_register_notifier(&vio_bus_type, &fail_iommu_bus_notifier);

return 0;
}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 86c799c97b77..361f4f255911 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -964,6 +964,8 @@ enum {
#define PCI_IRQ_MSIX (1 << 2) /* Allow MSI-X interrupts */
#define PCI_IRQ_AFFINITY (1 << 3) /* Auto-assign affinity */

+extern struct bus_type pci_bus_type;
+
/* These external functions are only available when PCI support is enabled */
#ifdef CONFIG_PCI

@@ -986,8 +988,6 @@ enum pcie_bus_config_types {

extern enum pcie_bus_config_types pcie_bus_config;

-extern struct bus_type pci_bus_type;
-
/* Do NOT directly access these two variables, unless you are arch-specific PCI
* code, or PCI core code. */
extern struct list_head pci_root_buses; /* List of all known PCI buses */

2021-04-06 03:30:34

by Randy Dunlap

[permalink] [raw]
Subject: Re: [PATCH v2] powerpc: iommu: fix build when neither PCI or IBMVIO is set

On 4/5/21 2:04 AM, Christophe Leroy wrote:
>
>
> Le 04/04/2021 à 21:26, Randy Dunlap a écrit :
>> When neither CONFIG_PCI nor CONFIG_IBMVIO is set/enabled, iommu.c has a
>> build error. The fault injection code is not useful in that kernel config,
>> so make the FAIL_IOMMU option depend on PCI || IBMVIO.
>>
>> Prevents this build error (warning escalated to error):
>> ../arch/powerpc/kernel/iommu.c:178:30: error: 'fail_iommu_bus_notifier' defined but not used [-Werror=unused-variable]
>>    178 | static struct notifier_block fail_iommu_bus_notifier = {
>>
>> Fixes: d6b9a81b2a45 ("powerpc: IOMMU fault injection")
>> Signed-off-by: Randy Dunlap <[email protected]>
>> Reported-by: kernel test robot <[email protected]>
>> Suggested-by: Michael Ellerman <[email protected]>
>> Cc: Michael Ellerman <[email protected]>
>> Cc: [email protected]
>> Cc: Anton Blanchard <[email protected]>
>> ---
>> I was supposed to update this about one month ago, but then I lost
>> some email and also took a break for a few weeks, then I remembered,
>> so here it is.
>>
>>   arch/powerpc/Kconfig.debug |    1 +
>>   1 file changed, 1 insertion(+)
>
> Wouldn't it be cleaner to get rid of those two horid #ifdefs ?
> Of course we can do both.

Sure, that works. Thanks.

Acked-by: Randy Dunlap <[email protected]> # build-tested


> diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
> index 216871414434..d691afa8acf8 100644
> --- a/arch/powerpc/kernel/iommu.c
> +++ b/arch/powerpc/kernel/iommu.c
> @@ -180,12 +180,10 @@ static struct notifier_block fail_iommu_bus_notifier = {
>
>  static int __init fail_iommu_setup(void)
>  {
> -#ifdef CONFIG_PCI
> -    bus_register_notifier(&pci_bus_type, &fail_iommu_bus_notifier);
> -#endif
> -#ifdef CONFIG_IBMVIO
> -    bus_register_notifier(&vio_bus_type, &fail_iommu_bus_notifier);
> -#endif
> +    if (IS_ENABLED(CONFIG_PCI))
> +        bus_register_notifier(&pci_bus_type, &fail_iommu_bus_notifier);
> +    if (IS_ENABLED(CONFIG_IBMVIO))
> +        bus_register_notifier(&vio_bus_type, &fail_iommu_bus_notifier);
>
>      return 0;
>  }
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 86c799c97b77..361f4f255911 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -964,6 +964,8 @@ enum {
>  #define PCI_IRQ_MSIX        (1 << 2) /* Allow MSI-X interrupts */
>  #define PCI_IRQ_AFFINITY    (1 << 3) /* Auto-assign affinity */
>
> +extern struct bus_type pci_bus_type;
> +
>  /* These external functions are only available when PCI support is enabled */
>  #ifdef CONFIG_PCI
>
> @@ -986,8 +988,6 @@ enum pcie_bus_config_types {
>
>  extern enum pcie_bus_config_types pcie_bus_config;
>
> -extern struct bus_type pci_bus_type;
> -
>  /* Do NOT directly access these two variables, unless you are arch-specific PCI
>   * code, or PCI core code. */
>  extern struct list_head pci_root_buses;    /* List of all known PCI buses */


--
~Randy

2021-04-10 14:32:25

by Michael Ellerman

[permalink] [raw]
Subject: Re: [PATCH v2] powerpc: iommu: fix build when neither PCI or IBMVIO is set

On Sun, 4 Apr 2021 12:26:23 -0700, Randy Dunlap wrote:
> When neither CONFIG_PCI nor CONFIG_IBMVIO is set/enabled, iommu.c has a
> build error. The fault injection code is not useful in that kernel config,
> so make the FAIL_IOMMU option depend on PCI || IBMVIO.
>
> Prevents this build error (warning escalated to error):
> ../arch/powerpc/kernel/iommu.c:178:30: error: 'fail_iommu_bus_notifier' defined but not used [-Werror=unused-variable]
> 178 | static struct notifier_block fail_iommu_bus_notifier = {

Applied to powerpc/next.

[1/1] powerpc: iommu: fix build when neither PCI or IBMVIO is set
https://git.kernel.org/powerpc/c/b27dadecdf9102838331b9a0b41ffc1cfe288154

cheers