Re: [PATCH v7 1/2] ACPI: APEI: explicit init HEST and GHES in apci_init

Nathan Chancellor
2022-02-21T18:27:16Z

Hi Shuai,

On Sat, Jan 22, 2022 at 01:26:17PM +0800, Shuai Xue wrote:
> From commit e147133a42cb ("ACPI / APEI: Make hest.c manage the estatus
> memory pool") was merged, ghes_init() relies on acpi_hest_init() to manage
> the estatus memory pool. On the other hand, ghes_init() relies on
> sdei_init() to detect the SDEI version and (un)register events. The
> dependencies are as follows:
>
> ghes_init() => acpi_hest_init() => acpi_bus_init() => acpi_init()
> ghes_init() => sdei_init()
>
> HEST is not PCI-specific and initcall ordering is implicit and not
> well-defined within a level.
>
> Based on above, remove acpi_hest_init() from acpi_pci_root_init() and
> convert ghes_init() and sdei_init() from initcalls to explicit calls in the
> following order:
>
> acpi_hest_init()
> ghes_init()
> sdei_init()
>
> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
> ---
> drivers/acpi/apei/ghes.c | 19 ++++++++-----------
> drivers/acpi/bus.c | 2 ++
> drivers/acpi/pci_root.c | 3 ---
> drivers/firmware/Kconfig | 1 +
> drivers/firmware/arm_sdei.c | 13 ++-----------
> include/acpi/apei.h | 4 +++-
> include/linux/arm_sdei.h | 2 ++
> 7 files changed, 18 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index 0c5c9acc6254..aadc0a972f18 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -1457,33 +1457,35 @@ static struct platform_driver ghes_platform_driver = {
> .remove = ghes_remove,
> };
>
> -static int __init ghes_init(void)
> +void __init ghes_init(void)
> {
> int rc;
>
> + sdei_init();
> +
> if (acpi_disabled)
> - return -ENODEV;
> + return;
>
> switch (hest_disable) {
> case HEST_NOT_FOUND:
> - return -ENODEV;
> + return;
> case HEST_DISABLED:
> pr_info(GHES_PFX "HEST is not enabled!\n");
> - return -EINVAL;
> + return;
> default:
> break;
> }
>
> if (ghes_disable) {
> pr_info(GHES_PFX "GHES is not enabled!\n");
> - return -EINVAL;
> + return;
> }
>
> ghes_nmi_init_cxt();
>
> rc = platform_driver_register(&ghes_platform_driver);
> if (rc)
> - goto err;
> + return;
>
> rc = apei_osc_setup();
> if (rc == 0 && osc_sb_apei_support_acked)
> @@ -1494,9 +1496,4 @@ static int __init ghes_init(void)
> pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n");
> else
> pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n");
> -
> - return 0;
> -err:
> - return rc;
> }
> -device_initcall(ghes_init);
> diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
> index 07f604832fd6..3f403db20f69 100644
> --- a/drivers/acpi/bus.c
> +++ b/drivers/acpi/bus.c
> @@ -1331,6 +1331,8 @@ static int __init acpi_init(void)
>
> pci_mmcfg_late_init();
> acpi_iort_init();
> + acpi_hest_init();
> + ghes_init();
> acpi_scan_init();
> acpi_ec_init();
> acpi_debugfs_init();
> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
> index b76db99cced3..6f9e75d14808 100644
> --- a/drivers/acpi/pci_root.c
> +++ b/drivers/acpi/pci_root.c
> @@ -22,8 +22,6 @@
> #include <linux/slab.h>
> #include <linux/dmi.h>
> #include <linux/platform_data/x86/apple.h>
> -#include <acpi/apei.h> /* for acpi_hest_init() */
> -
> #include "internal.h"
>
> #define ACPI_PCI_ROOT_CLASS "pci_bridge"
> @@ -943,7 +941,6 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>
> void __init acpi_pci_root_init(void)
> {
> - acpi_hest_init();
> if (acpi_pci_disabled)
> return;
>
> diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
> index 75cb91055c17..ad114d9cdf8e 100644
> --- a/drivers/firmware/Kconfig
> +++ b/drivers/firmware/Kconfig
> @@ -40,6 +40,7 @@ config ARM_SCPI_POWER_DOMAIN
> config ARM_SDE_INTERFACE
> bool "ARM Software Delegated Exception Interface (SDEI)"
> depends on ARM64
> + select ACPI_APEI_GHES

As the kernel test robot pointed out [1], you cannot do this.
CONFIG_ACPI_APEI_GHES is a user selectable symbol that has dependencies,
which 'select' completely overrides, resulting in build failures when
CONFIG_ACPI_APEI is not enabled.

If CONFIG_ARM_SDE_INTERFACE truly requires CONFIG_ACPI_APEI_GHES, you
should have "depends on ACPI_APEI_GHES".

If CONFIG_ARM_SDE_INTERFACE soft depends on CONFIG_ACPI_APEI_GHES for
functionality but can work without it, you could use
"imply ACPI_APEI_GHES", which will enable CONFIG_ACPI_APEI_GHES if its
dependencies are met.

I noticed the same error with Alpine Linux's aarch64 configuration [2]
if you wanted a quick configuration to test with.

[1]: https://lore.kernel.org/r/202202151504.jWpZGPaH-lkp@intel.com/
[2]: https://git.alpinelinux.org/aports/plain/community/linux-edge/config-edge.aarch64

Cheers,
Nathan

> help
> The Software Delegated Exception Interface (SDEI) is an ARM
> standard for registering callbacks from the platform firmware
> diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c
> index a7e762c352f9..1e1a51510e83 100644
> --- a/drivers/firmware/arm_sdei.c
> +++ b/drivers/firmware/arm_sdei.c
> @@ -1059,14 +1059,14 @@ static bool __init sdei_present_acpi(void)
> return true;
> }
>
> -static int __init sdei_init(void)
> +void __init sdei_init(void)
> {
> struct platform_device *pdev;
> int ret;
>
> ret = platform_driver_register(&sdei_driver);
> if (ret || !sdei_present_acpi())
> - return ret;
> + return;
>
> pdev = platform_device_register_simple(sdei_driver.driver.name,
> 0, NULL, 0);
> @@ -1076,17 +1076,8 @@ static int __init sdei_init(void)
> pr_info("Failed to register ACPI:SDEI platform device %d\n",
> ret);
> }
> -
> - return ret;
> }
>
> -/*
> - * On an ACPI system SDEI needs to be ready before HEST:GHES tries to register
> - * its events. ACPI is initialised from a subsys_initcall(), GHES is initialised
> - * by device_initcall(). We want to be called in the middle.
> - */
> -subsys_initcall_sync(sdei_init);
> -
> int sdei_event_handler(struct pt_regs *regs,
> struct sdei_registered_event *arg)
> {
> diff --git a/include/acpi/apei.h b/include/acpi/apei.h
> index ece0a8af2bae..4e60dd73c3bb 100644
> --- a/include/acpi/apei.h
> +++ b/include/acpi/apei.h
> @@ -27,14 +27,16 @@ extern int hest_disable;
> extern int erst_disable;
> #ifdef CONFIG_ACPI_APEI_GHES
> extern bool ghes_disable;
> +void __init ghes_init(void);
> #else
> #define ghes_disable 1
> +static inline void ghes_init(void) { }
> #endif
>
> #ifdef CONFIG_ACPI_APEI
> void __init acpi_hest_init(void);
> #else
> -static inline void acpi_hest_init(void) { return; }
> +static inline void acpi_hest_init(void) { }
> #endif
>
> int erst_write(const struct cper_record_header *record);
> diff --git a/include/linux/arm_sdei.h b/include/linux/arm_sdei.h
> index 0a241c5c911d..14dc461b0e82 100644
> --- a/include/linux/arm_sdei.h
> +++ b/include/linux/arm_sdei.h
> @@ -46,9 +46,11 @@ int sdei_unregister_ghes(struct ghes *ghes);
> /* For use by arch code when CPU hotplug notifiers are not appropriate. */
> int sdei_mask_local_cpu(void);
> int sdei_unmask_local_cpu(void);
> +void __init sdei_init(void);
> #else
> static inline int sdei_mask_local_cpu(void) { return 0; }
> static inline int sdei_unmask_local_cpu(void) { return 0; }
> +static inline void sdei_init(void) { }
> #endif /* CONFIG_ARM_SDE_INTERFACE */
>
>
> --
> 2.20.1.12.g72788fdb
>
>