[linux-next,3/3] powerpc/kdump: Split KEXEC_CORE and CRASH_DUMP dependency

Message ID 20240213113150.1148276-4-hbathini@linux.ibm.com
State New
Headers
Series powerpc/kexec: split CONFIG_CRASH_DUMP out from CONFIG_KEXEC_CORE |

Commit Message

Hari Bathini Feb. 13, 2024, 11:31 a.m. UTC
  Remove CONFIG_CRASH_DUMP dependency on CONFIG_KEXEC. CONFIG_KEXEC_CORE
was used at places where CONFIG_CRASH_DUMP or CONFIG_CRASH_RESERVE was
appropriate. Replace with appropriate #ifdefs to support CONFIG_KEXEC
and !CONFIG_CRASH_DUMP configuration option. Also, make CONFIG_FA_DUMP
dependent on CONFIG_CRASH_DUMP to avoid unmet dependencies for FA_DUMP
with !CONFIG_KEXEC_CORE configuration option.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
 arch/powerpc/Kconfig               |  9 +--
 arch/powerpc/include/asm/kexec.h   | 98 +++++++++++++++---------------
 arch/powerpc/kernel/prom.c         |  2 +-
 arch/powerpc/kernel/setup-common.c |  2 +-
 arch/powerpc/kernel/smp.c          |  4 +-
 arch/powerpc/kexec/Makefile        |  3 +-
 arch/powerpc/kexec/core.c          |  4 ++
 7 files changed, 60 insertions(+), 62 deletions(-)
  

Comments

Sourabh Jain Feb. 23, 2024, 7:35 a.m. UTC | #1
Hello Hari,

Build failure detected.

On 13/02/24 17:01, Hari Bathini wrote:
> Remove CONFIG_CRASH_DUMP dependency on CONFIG_KEXEC. CONFIG_KEXEC_CORE
> was used at places where CONFIG_CRASH_DUMP or CONFIG_CRASH_RESERVE was
> appropriate. Replace with appropriate #ifdefs to support CONFIG_KEXEC
> and !CONFIG_CRASH_DUMP configuration option. Also, make CONFIG_FA_DUMP
> dependent on CONFIG_CRASH_DUMP to avoid unmet dependencies for FA_DUMP
> with !CONFIG_KEXEC_CORE configuration option.
>
> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
> ---
>   arch/powerpc/Kconfig               |  9 +--
>   arch/powerpc/include/asm/kexec.h   | 98 +++++++++++++++---------------
>   arch/powerpc/kernel/prom.c         |  2 +-
>   arch/powerpc/kernel/setup-common.c |  2 +-
>   arch/powerpc/kernel/smp.c          |  4 +-
>   arch/powerpc/kexec/Makefile        |  3 +-
>   arch/powerpc/kexec/core.c          |  4 ++
>   7 files changed, 60 insertions(+), 62 deletions(-)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 5cf8ad8d7e8e..e377deefa2dc 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -607,11 +607,6 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
>   config ARCH_SUPPORTS_KEXEC
>   	def_bool PPC_BOOK3S || PPC_E500 || (44x && !SMP)
>   
> -config ARCH_SELECTS_KEXEC
> -	def_bool y
> -	depends on KEXEC
> -	select CRASH_DUMP
> -
>   config ARCH_SUPPORTS_KEXEC_FILE
>   	def_bool PPC64
>   
> @@ -622,7 +617,6 @@ config ARCH_SELECTS_KEXEC_FILE
>   	def_bool y
>   	depends on KEXEC_FILE
>   	select KEXEC_ELF
> -	select CRASH_DUMP
>   	select HAVE_IMA_KEXEC if IMA
>   
>   config PPC64_BIG_ENDIAN_ELF_ABI_V2
> @@ -694,8 +688,7 @@ config ARCH_SELECTS_CRASH_DUMP
>   
>   config FA_DUMP
>   	bool "Firmware-assisted dump"
> -	depends on PPC64 && (PPC_RTAS || PPC_POWERNV)
> -	select CRASH_DUMP
> +	depends on CRASH_DUMP && PPC64 && (PPC_RTAS || PPC_POWERNV)
>   	help
>   	  A robust mechanism to get reliable kernel crash dump with
>   	  assistance from firmware. This approach does not use kexec,
> diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
> index e1b43aa12175..fdb90e24dc74 100644
> --- a/arch/powerpc/include/asm/kexec.h
> +++ b/arch/powerpc/include/asm/kexec.h
> @@ -55,59 +55,18 @@
>   typedef void (*crash_shutdown_t)(void);
>   
>   #ifdef CONFIG_KEXEC_CORE
> -
> -/*
> - * This function is responsible for capturing register states if coming
> - * via panic or invoking dump using sysrq-trigger.
> - */
> -static inline void crash_setup_regs(struct pt_regs *newregs,
> -					struct pt_regs *oldregs)
> -{
> -	if (oldregs)
> -		memcpy(newregs, oldregs, sizeof(*newregs));
> -	else
> -		ppc_save_regs(newregs);
> -}
> +struct kimage;
> +struct pt_regs;
>   
>   extern void kexec_smp_wait(void);	/* get and clear naca physid, wait for
>   					  master to copy new code to 0 */
> -extern int crashing_cpu;
> -extern void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *));
> -extern void crash_ipi_callback(struct pt_regs *);
> -extern int crash_wake_offline;
> -
> -struct kimage;
> -struct pt_regs;
>   extern void default_machine_kexec(struct kimage *image);
> -extern void default_machine_crash_shutdown(struct pt_regs *regs);
> -extern int crash_shutdown_register(crash_shutdown_t handler);
> -extern int crash_shutdown_unregister(crash_shutdown_t handler);
> -
> -extern void crash_kexec_prepare(void);
> -extern void crash_kexec_secondary(struct pt_regs *regs);
> -int __init overlaps_crashkernel(unsigned long start, unsigned long size);
> -extern void reserve_crashkernel(void);
>   extern void machine_kexec_mask_interrupts(void);
>   
> -static inline bool kdump_in_progress(void)
> -{
> -	return crashing_cpu >= 0;
> -}
> -
>   void relocate_new_kernel(unsigned long indirection_page, unsigned long reboot_code_buffer,
>   			 unsigned long start_address) __noreturn;
> -
>   void kexec_copy_flush(struct kimage *image);
>   
> -#if defined(CONFIG_CRASH_DUMP)
> -bool is_kdump_kernel(void);
> -#define is_kdump_kernel			is_kdump_kernel
> -#if defined(CONFIG_PPC_RTAS)
> -void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
> -#define crash_free_reserved_phys_range crash_free_reserved_phys_range
> -#endif /* CONFIG_PPC_RTAS */
> -#endif /* CONFIG_CRASH_DUMP */
> -
>   #ifdef CONFIG_KEXEC_FILE
>   extern const struct kexec_file_ops kexec_elf64_ops;
>   
> @@ -152,15 +111,56 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
>   
>   #endif /* CONFIG_KEXEC_FILE */
>   
> -#else /* !CONFIG_KEXEC_CORE */
> -static inline void crash_kexec_secondary(struct pt_regs *regs) { }
> +#endif /* CONFIG_KEXEC_CORE */
> +
> +#ifdef CONFIG_CRASH_RESERVE
> +int __init overlaps_crashkernel(unsigned long start, unsigned long size);
> +extern void reserve_crashkernel(void);
> +#else
> +static inline void reserve_crashkernel(void) {}
> +static inline int overlaps_crashkernel(unsigned long start, unsigned long size) { return 0; }
> +#endif
>   
> -static inline int overlaps_crashkernel(unsigned long start, unsigned long size)
> +#if defined(CONFIG_CRASH_DUMP)
> +/*
> + * This function is responsible for capturing register states if coming
> + * via panic or invoking dump using sysrq-trigger.
> + */
> +static inline void crash_setup_regs(struct pt_regs *newregs,
> +					struct pt_regs *oldregs)
>   {
> -	return 0;
> +	if (oldregs)
> +		memcpy(newregs, oldregs, sizeof(*newregs));
> +	else
> +		ppc_save_regs(newregs);
> +}
> +
> +extern int crashing_cpu;
> +extern void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *));
> +extern void crash_ipi_callback(struct pt_regs *regs);
> +extern int crash_wake_offline;
> +
> +extern int crash_shutdown_register(crash_shutdown_t handler);
> +extern int crash_shutdown_unregister(crash_shutdown_t handler);
> +extern void default_machine_crash_shutdown(struct pt_regs *regs);
> +
> +extern void crash_kexec_prepare(void);
> +extern void crash_kexec_secondary(struct pt_regs *regs);
> +
> +static inline bool kdump_in_progress(void)
> +{
> +	return crashing_cpu >= 0;
>   }
>   
> -static inline void reserve_crashkernel(void) { ; }
> +bool is_kdump_kernel(void);
> +#define is_kdump_kernel			is_kdump_kernel
> +#if defined(CONFIG_PPC_RTAS)
> +void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
> +#define crash_free_reserved_phys_range crash_free_reserved_phys_range
> +#endif /* CONFIG_PPC_RTAS */
> +
> +#else /* !CONFIG_CRASH_DUMP */
> +static inline void crash_kexec_secondary(struct pt_regs *regs) { }
>   
>   static inline int crash_shutdown_register(crash_shutdown_t handler)
>   {
> @@ -183,7 +183,7 @@ static inline void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
>   {
>   }
>   
> -#endif /* CONFIG_KEXEC_CORE */
> +#endif /* CONFIG_CRASH_DUMP */
>   
>   #ifdef CONFIG_PPC_BOOK3S_64
>   #include <asm/book3s/64/kexec.h>
> diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
> index 0b5878c3125b..1edc34b711ba 100644
> --- a/arch/powerpc/kernel/prom.c
> +++ b/arch/powerpc/kernel/prom.c
> @@ -453,7 +453,7 @@ static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
>   		tce_alloc_end = *lprop;
>   #endif
>   
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_RESERVE
>   	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
>   	if (lprop)
>   		crashk_res.start = *lprop;
> diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
> index 733f210ffda1..35cac3eaaf75 100644
> --- a/arch/powerpc/kernel/setup-common.c
> +++ b/arch/powerpc/kernel/setup-common.c
> @@ -109,7 +109,7 @@ int ppc_do_canonicalize_irqs;
>   EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
>   #endif
>   
> -#ifdef CONFIG_VMCORE_INFO
> +#ifdef CONFIG_CRASH_DUMP
>   /* This keeps a track of which one is the crashing cpu. */
>   int crashing_cpu = -1;
>   #endif
> diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
> index 693334c20d07..aa81c95c73a4 100644
> --- a/arch/powerpc/kernel/smp.c
> +++ b/arch/powerpc/kernel/smp.c
> @@ -588,7 +588,7 @@ void smp_send_debugger_break(void)
>   }
>   #endif
>   
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
>   void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
>   {
>   	int cpu;
> @@ -631,7 +631,7 @@ void crash_smp_send_stop(void)
>   
>   	stopped = true;
>   
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
>   	if (kexec_crash_image) {
>   		crash_kexec_prepare();
>   		return;
> diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
> index 91e96f5168b7..8e469c4da3f8 100644
> --- a/arch/powerpc/kexec/Makefile
> +++ b/arch/powerpc/kexec/Makefile
> @@ -3,12 +3,13 @@
>   # Makefile for the linux kernel.
>   #
>   
> -obj-y				+= core.o crash.o core_$(BITS).o
> +obj-y				+= core.o core_$(BITS).o
>   
>   obj-$(CONFIG_PPC32)		+= relocate_32.o
>   
>   obj-$(CONFIG_KEXEC_FILE)	+= file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o
>   obj-$(CONFIG_VMCORE_INFO)	+= vmcore_info.o
> +obj-$(CONFIG_CRASH_DUMP)	+= crash.o


Observed a build failure with this patch.

arch/powerpc/platforms/powernv/smp.c: In function ‘pnv_smp_init’:
arch/powerpc/platforms/powernv/smp.c:438:2: error: ‘crash_wake_offline’ 
undeclared (first use in this function); did you mean ‘cpu_is_offline’?
   crash_wake_offline = 1;
   ^~~~~~~~~~~~~~~~~~
   cpu_is_offline
arch/powerpc/platforms/powernv/smp.c:438:2: note: each undeclared 
identifier is reported only once for each function it appears in
make[5]: *** [scripts/Makefile.build:244: 
arch/powerpc/platforms/powernv/smp.o] Error 1

CONFIG:

CONFIG_KEXEC=y
CONFIG_KEXEC_FILE=y
# CONFIG_CRASH_DUMP is not set

Below changes fixes the above issue:

diff --git a/arch/powerpc/platforms/powernv/smp.c 
b/arch/powerpc/platforms/powernv/smp.c
index 9e1a25398f98..8f14f0581a21 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -434,7 +434,7 @@ void __init pnv_smp_init(void)
         smp_ops = &pnv_smp_ops;

  #ifdef CONFIG_HOTPLUG_CPU
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
         crash_wake_offline = 1;
  #endif
  #endif

Thanks,
Sourabh



>   
>   # Disable GCOV, KCOV & sanitizers in odd or sensitive code
>   GCOV_PROFILE_core_$(BITS).o := n
> diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c
> index 3ff4411ed496..b8333a49ea5d 100644
> --- a/arch/powerpc/kexec/core.c
> +++ b/arch/powerpc/kexec/core.c
> @@ -44,10 +44,12 @@ void machine_kexec_mask_interrupts(void) {
>   	}
>   }
>   
> +#ifdef CONFIG_CRASH_DUMP
>   void machine_crash_shutdown(struct pt_regs *regs)
>   {
>   	default_machine_crash_shutdown(regs);
>   }
> +#endif
>   
>   void machine_kexec_cleanup(struct kimage *image)
>   {
> @@ -77,6 +79,7 @@ void machine_kexec(struct kimage *image)
>   	for(;;);
>   }
>   
> +#ifdef CONFIG_CRASH_RESERVE
>   void __init reserve_crashkernel(void)
>   {
>   	unsigned long long crash_size, crash_base, total_mem_sz;
> @@ -251,3 +254,4 @@ static int __init kexec_setup(void)
>   	return 0;
>   }
>   late_initcall(kexec_setup);
> +#endif /* CONFIG_CRASH_RESERVE */
  
Hari Bathini Feb. 26, 2024, 6:23 a.m. UTC | #2
On 23/02/24 1:05 pm, Sourabh Jain wrote:
> Hello Hari,

Hi Sourabh,

> 
> Build failure detected.

Thanks for trying out the patches.

> 
> On 13/02/24 17:01, Hari Bathini wrote:
>> Remove CONFIG_CRASH_DUMP dependency on CONFIG_KEXEC. CONFIG_KEXEC_CORE
>> was used at places where CONFIG_CRASH_DUMP or CONFIG_CRASH_RESERVE was
>> appropriate. Replace with appropriate #ifdefs to support CONFIG_KEXEC
>> and !CONFIG_CRASH_DUMP configuration option. Also, make CONFIG_FA_DUMP
>> dependent on CONFIG_CRASH_DUMP to avoid unmet dependencies for FA_DUMP
>> with !CONFIG_KEXEC_CORE configuration option.
>>
>> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
>> ---
>>   arch/powerpc/Kconfig               |  9 +--
>>   arch/powerpc/include/asm/kexec.h   | 98 +++++++++++++++---------------
>>   arch/powerpc/kernel/prom.c         |  2 +-
>>   arch/powerpc/kernel/setup-common.c |  2 +-
>>   arch/powerpc/kernel/smp.c          |  4 +-
>>   arch/powerpc/kexec/Makefile        |  3 +-
>>   arch/powerpc/kexec/core.c          |  4 ++
>>   7 files changed, 60 insertions(+), 62 deletions(-)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 5cf8ad8d7e8e..e377deefa2dc 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -607,11 +607,6 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
>>   config ARCH_SUPPORTS_KEXEC
>>       def_bool PPC_BOOK3S || PPC_E500 || (44x && !SMP)
>> -config ARCH_SELECTS_KEXEC
>> -    def_bool y
>> -    depends on KEXEC
>> -    select CRASH_DUMP
>> -
>>   config ARCH_SUPPORTS_KEXEC_FILE
>>       def_bool PPC64
>> @@ -622,7 +617,6 @@ config ARCH_SELECTS_KEXEC_FILE
>>       def_bool y
>>       depends on KEXEC_FILE
>>       select KEXEC_ELF
>> -    select CRASH_DUMP
>>       select HAVE_IMA_KEXEC if IMA
>>   config PPC64_BIG_ENDIAN_ELF_ABI_V2
>> @@ -694,8 +688,7 @@ config ARCH_SELECTS_CRASH_DUMP
>>   config FA_DUMP
>>       bool "Firmware-assisted dump"
>> -    depends on PPC64 && (PPC_RTAS || PPC_POWERNV)
>> -    select CRASH_DUMP
>> +    depends on CRASH_DUMP && PPC64 && (PPC_RTAS || PPC_POWERNV)
>>       help
>>         A robust mechanism to get reliable kernel crash dump with
>>         assistance from firmware. This approach does not use kexec,
>> diff --git a/arch/powerpc/include/asm/kexec.h 
>> b/arch/powerpc/include/asm/kexec.h
>> index e1b43aa12175..fdb90e24dc74 100644
>> --- a/arch/powerpc/include/asm/kexec.h
>> +++ b/arch/powerpc/include/asm/kexec.h
>> @@ -55,59 +55,18 @@
>>   typedef void (*crash_shutdown_t)(void);
>>   #ifdef CONFIG_KEXEC_CORE
>> -
>> -/*
>> - * This function is responsible for capturing register states if coming
>> - * via panic or invoking dump using sysrq-trigger.
>> - */
>> -static inline void crash_setup_regs(struct pt_regs *newregs,
>> -                    struct pt_regs *oldregs)
>> -{
>> -    if (oldregs)
>> -        memcpy(newregs, oldregs, sizeof(*newregs));
>> -    else
>> -        ppc_save_regs(newregs);
>> -}
>> +struct kimage;
>> +struct pt_regs;
>>   extern void kexec_smp_wait(void);    /* get and clear naca physid, 
>> wait for
>>                         master to copy new code to 0 */
>> -extern int crashing_cpu;
>> -extern void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs 
>> *));
>> -extern void crash_ipi_callback(struct pt_regs *);
>> -extern int crash_wake_offline;
>> -
>> -struct kimage;
>> -struct pt_regs;
>>   extern void default_machine_kexec(struct kimage *image);
>> -extern void default_machine_crash_shutdown(struct pt_regs *regs);
>> -extern int crash_shutdown_register(crash_shutdown_t handler);
>> -extern int crash_shutdown_unregister(crash_shutdown_t handler);
>> -
>> -extern void crash_kexec_prepare(void);
>> -extern void crash_kexec_secondary(struct pt_regs *regs);
>> -int __init overlaps_crashkernel(unsigned long start, unsigned long 
>> size);
>> -extern void reserve_crashkernel(void);
>>   extern void machine_kexec_mask_interrupts(void);
>> -static inline bool kdump_in_progress(void)
>> -{
>> -    return crashing_cpu >= 0;
>> -}
>> -
>>   void relocate_new_kernel(unsigned long indirection_page, unsigned 
>> long reboot_code_buffer,
>>                unsigned long start_address) __noreturn;
>> -
>>   void kexec_copy_flush(struct kimage *image);
>> -#if defined(CONFIG_CRASH_DUMP)
>> -bool is_kdump_kernel(void);
>> -#define is_kdump_kernel            is_kdump_kernel
>> -#if defined(CONFIG_PPC_RTAS)
>> -void crash_free_reserved_phys_range(unsigned long begin, unsigned 
>> long end);
>> -#define crash_free_reserved_phys_range crash_free_reserved_phys_range
>> -#endif /* CONFIG_PPC_RTAS */
>> -#endif /* CONFIG_CRASH_DUMP */
>> -
>>   #ifdef CONFIG_KEXEC_FILE
>>   extern const struct kexec_file_ops kexec_elf64_ops;
>> @@ -152,15 +111,56 @@ int setup_new_fdt_ppc64(const struct kimage 
>> *image, void *fdt,
>>   #endif /* CONFIG_KEXEC_FILE */
>> -#else /* !CONFIG_KEXEC_CORE */
>> -static inline void crash_kexec_secondary(struct pt_regs *regs) { }
>> +#endif /* CONFIG_KEXEC_CORE */
>> +
>> +#ifdef CONFIG_CRASH_RESERVE
>> +int __init overlaps_crashkernel(unsigned long start, unsigned long 
>> size);
>> +extern void reserve_crashkernel(void);
>> +#else
>> +static inline void reserve_crashkernel(void) {}
>> +static inline int overlaps_crashkernel(unsigned long start, unsigned 
>> long size) { return 0; }
>> +#endif
>> -static inline int overlaps_crashkernel(unsigned long start, unsigned 
>> long size)
>> +#if defined(CONFIG_CRASH_DUMP)
>> +/*
>> + * This function is responsible for capturing register states if coming
>> + * via panic or invoking dump using sysrq-trigger.
>> + */
>> +static inline void crash_setup_regs(struct pt_regs *newregs,
>> +                    struct pt_regs *oldregs)
>>   {
>> -    return 0;
>> +    if (oldregs)
>> +        memcpy(newregs, oldregs, sizeof(*newregs));
>> +    else
>> +        ppc_save_regs(newregs);
>> +}
>> +
>> +extern int crashing_cpu;
>> +extern void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs 
>> *));
>> +extern void crash_ipi_callback(struct pt_regs *regs);
>> +extern int crash_wake_offline;
>> +
>> +extern int crash_shutdown_register(crash_shutdown_t handler);
>> +extern int crash_shutdown_unregister(crash_shutdown_t handler);
>> +extern void default_machine_crash_shutdown(struct pt_regs *regs);
>> +
>> +extern void crash_kexec_prepare(void);
>> +extern void crash_kexec_secondary(struct pt_regs *regs);
>> +
>> +static inline bool kdump_in_progress(void)
>> +{
>> +    return crashing_cpu >= 0;
>>   }
>> -static inline void reserve_crashkernel(void) { ; }
>> +bool is_kdump_kernel(void);
>> +#define is_kdump_kernel            is_kdump_kernel
>> +#if defined(CONFIG_PPC_RTAS)
>> +void crash_free_reserved_phys_range(unsigned long begin, unsigned 
>> long end);
>> +#define crash_free_reserved_phys_range crash_free_reserved_phys_range
>> +#endif /* CONFIG_PPC_RTAS */
>> +
>> +#else /* !CONFIG_CRASH_DUMP */
>> +static inline void crash_kexec_secondary(struct pt_regs *regs) { }
>>   static inline int crash_shutdown_register(crash_shutdown_t handler)
>>   {
>> @@ -183,7 +183,7 @@ static inline void crash_send_ipi(void 
>> (*crash_ipi_callback)(struct pt_regs *))
>>   {
>>   }
>> -#endif /* CONFIG_KEXEC_CORE */
>> +#endif /* CONFIG_CRASH_DUMP */
>>   #ifdef CONFIG_PPC_BOOK3S_64
>>   #include <asm/book3s/64/kexec.h>
>> diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
>> index 0b5878c3125b..1edc34b711ba 100644
>> --- a/arch/powerpc/kernel/prom.c
>> +++ b/arch/powerpc/kernel/prom.c
>> @@ -453,7 +453,7 @@ static int __init 
>> early_init_dt_scan_chosen_ppc(unsigned long node,
>>           tce_alloc_end = *lprop;
>>   #endif
>> -#ifdef CONFIG_KEXEC_CORE
>> +#ifdef CONFIG_CRASH_RESERVE
>>       lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
>>       if (lprop)
>>           crashk_res.start = *lprop;
>> diff --git a/arch/powerpc/kernel/setup-common.c 
>> b/arch/powerpc/kernel/setup-common.c
>> index 733f210ffda1..35cac3eaaf75 100644
>> --- a/arch/powerpc/kernel/setup-common.c
>> +++ b/arch/powerpc/kernel/setup-common.c
>> @@ -109,7 +109,7 @@ int ppc_do_canonicalize_irqs;
>>   EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
>>   #endif
>> -#ifdef CONFIG_VMCORE_INFO
>> +#ifdef CONFIG_CRASH_DUMP
>>   /* This keeps a track of which one is the crashing cpu. */
>>   int crashing_cpu = -1;
>>   #endif
>> diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
>> index 693334c20d07..aa81c95c73a4 100644
>> --- a/arch/powerpc/kernel/smp.c
>> +++ b/arch/powerpc/kernel/smp.c
>> @@ -588,7 +588,7 @@ void smp_send_debugger_break(void)
>>   }
>>   #endif
>> -#ifdef CONFIG_KEXEC_CORE
>> +#ifdef CONFIG_CRASH_DUMP
>>   void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
>>   {
>>       int cpu;
>> @@ -631,7 +631,7 @@ void crash_smp_send_stop(void)
>>       stopped = true;
>> -#ifdef CONFIG_KEXEC_CORE
>> +#ifdef CONFIG_CRASH_DUMP
>>       if (kexec_crash_image) {
>>           crash_kexec_prepare();
>>           return;
>> diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
>> index 91e96f5168b7..8e469c4da3f8 100644
>> --- a/arch/powerpc/kexec/Makefile
>> +++ b/arch/powerpc/kexec/Makefile
>> @@ -3,12 +3,13 @@
>>   # Makefile for the linux kernel.
>>   #
>> -obj-y                += core.o crash.o core_$(BITS).o
>> +obj-y                += core.o core_$(BITS).o
>>   obj-$(CONFIG_PPC32)        += relocate_32.o
>>   obj-$(CONFIG_KEXEC_FILE)    += file_load.o ranges.o 
>> file_load_$(BITS).o elf_$(BITS).o
>>   obj-$(CONFIG_VMCORE_INFO)    += vmcore_info.o
>> +obj-$(CONFIG_CRASH_DUMP)    += crash.o
> 
> 
> Observed a build failure with this patch.
> 
> arch/powerpc/platforms/powernv/smp.c: In function ‘pnv_smp_init’:
> arch/powerpc/platforms/powernv/smp.c:438:2: error: ‘crash_wake_offline’ 
> undeclared (first use in this function); did you mean ‘cpu_is_offline’?
>    crash_wake_offline = 1;
>    ^~~~~~~~~~~~~~~~~~
>    cpu_is_offline
> arch/powerpc/platforms/powernv/smp.c:438:2: note: each undeclared 
> identifier is reported only once for each function it appears in
> make[5]: *** [scripts/Makefile.build:244: 
> arch/powerpc/platforms/powernv/smp.o] Error 1
> 
> CONFIG:
> 
> CONFIG_KEXEC=y
> CONFIG_KEXEC_FILE=y
> # CONFIG_CRASH_DUMP is not set
> 
> Below changes fixes the above issue:
> 
> diff --git a/arch/powerpc/platforms/powernv/smp.c 
> b/arch/powerpc/platforms/powernv/smp.c
> index 9e1a25398f98..8f14f0581a21 100644
> --- a/arch/powerpc/platforms/powernv/smp.c
> +++ b/arch/powerpc/platforms/powernv/smp.c
> @@ -434,7 +434,7 @@ void __init pnv_smp_init(void)
>          smp_ops = &pnv_smp_ops;
> 
>   #ifdef CONFIG_HOTPLUG_CPU
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
>          crash_wake_offline = 1;
>   #endif
>   #endif

Right. Missed testing with CONFIG_PPC_POWERNV.
Will post v2.

Thanks
Hari
  

Patch

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 5cf8ad8d7e8e..e377deefa2dc 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -607,11 +607,6 @@  config PPC64_SUPPORTS_MEMORY_FAILURE
 config ARCH_SUPPORTS_KEXEC
 	def_bool PPC_BOOK3S || PPC_E500 || (44x && !SMP)
 
-config ARCH_SELECTS_KEXEC
-	def_bool y
-	depends on KEXEC
-	select CRASH_DUMP
-
 config ARCH_SUPPORTS_KEXEC_FILE
 	def_bool PPC64
 
@@ -622,7 +617,6 @@  config ARCH_SELECTS_KEXEC_FILE
 	def_bool y
 	depends on KEXEC_FILE
 	select KEXEC_ELF
-	select CRASH_DUMP
 	select HAVE_IMA_KEXEC if IMA
 
 config PPC64_BIG_ENDIAN_ELF_ABI_V2
@@ -694,8 +688,7 @@  config ARCH_SELECTS_CRASH_DUMP
 
 config FA_DUMP
 	bool "Firmware-assisted dump"
-	depends on PPC64 && (PPC_RTAS || PPC_POWERNV)
-	select CRASH_DUMP
+	depends on CRASH_DUMP && PPC64 && (PPC_RTAS || PPC_POWERNV)
 	help
 	  A robust mechanism to get reliable kernel crash dump with
 	  assistance from firmware. This approach does not use kexec,
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index e1b43aa12175..fdb90e24dc74 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -55,59 +55,18 @@ 
 typedef void (*crash_shutdown_t)(void);
 
 #ifdef CONFIG_KEXEC_CORE
-
-/*
- * This function is responsible for capturing register states if coming
- * via panic or invoking dump using sysrq-trigger.
- */
-static inline void crash_setup_regs(struct pt_regs *newregs,
-					struct pt_regs *oldregs)
-{
-	if (oldregs)
-		memcpy(newregs, oldregs, sizeof(*newregs));
-	else
-		ppc_save_regs(newregs);
-}
+struct kimage;
+struct pt_regs;
 
 extern void kexec_smp_wait(void);	/* get and clear naca physid, wait for
 					  master to copy new code to 0 */
-extern int crashing_cpu;
-extern void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *));
-extern void crash_ipi_callback(struct pt_regs *);
-extern int crash_wake_offline;
-
-struct kimage;
-struct pt_regs;
 extern void default_machine_kexec(struct kimage *image);
-extern void default_machine_crash_shutdown(struct pt_regs *regs);
-extern int crash_shutdown_register(crash_shutdown_t handler);
-extern int crash_shutdown_unregister(crash_shutdown_t handler);
-
-extern void crash_kexec_prepare(void);
-extern void crash_kexec_secondary(struct pt_regs *regs);
-int __init overlaps_crashkernel(unsigned long start, unsigned long size);
-extern void reserve_crashkernel(void);
 extern void machine_kexec_mask_interrupts(void);
 
-static inline bool kdump_in_progress(void)
-{
-	return crashing_cpu >= 0;
-}
-
 void relocate_new_kernel(unsigned long indirection_page, unsigned long reboot_code_buffer,
 			 unsigned long start_address) __noreturn;
-
 void kexec_copy_flush(struct kimage *image);
 
-#if defined(CONFIG_CRASH_DUMP)
-bool is_kdump_kernel(void);
-#define is_kdump_kernel			is_kdump_kernel
-#if defined(CONFIG_PPC_RTAS)
-void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
-#define crash_free_reserved_phys_range crash_free_reserved_phys_range
-#endif /* CONFIG_PPC_RTAS */
-#endif /* CONFIG_CRASH_DUMP */
-
 #ifdef CONFIG_KEXEC_FILE
 extern const struct kexec_file_ops kexec_elf64_ops;
 
@@ -152,15 +111,56 @@  int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
 
 #endif /* CONFIG_KEXEC_FILE */
 
-#else /* !CONFIG_KEXEC_CORE */
-static inline void crash_kexec_secondary(struct pt_regs *regs) { }
+#endif /* CONFIG_KEXEC_CORE */
+
+#ifdef CONFIG_CRASH_RESERVE
+int __init overlaps_crashkernel(unsigned long start, unsigned long size);
+extern void reserve_crashkernel(void);
+#else
+static inline void reserve_crashkernel(void) {}
+static inline int overlaps_crashkernel(unsigned long start, unsigned long size) { return 0; }
+#endif
 
-static inline int overlaps_crashkernel(unsigned long start, unsigned long size)
+#if defined(CONFIG_CRASH_DUMP)
+/*
+ * This function is responsible for capturing register states if coming
+ * via panic or invoking dump using sysrq-trigger.
+ */
+static inline void crash_setup_regs(struct pt_regs *newregs,
+					struct pt_regs *oldregs)
 {
-	return 0;
+	if (oldregs)
+		memcpy(newregs, oldregs, sizeof(*newregs));
+	else
+		ppc_save_regs(newregs);
+}
+
+extern int crashing_cpu;
+extern void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *));
+extern void crash_ipi_callback(struct pt_regs *regs);
+extern int crash_wake_offline;
+
+extern int crash_shutdown_register(crash_shutdown_t handler);
+extern int crash_shutdown_unregister(crash_shutdown_t handler);
+extern void default_machine_crash_shutdown(struct pt_regs *regs);
+
+extern void crash_kexec_prepare(void);
+extern void crash_kexec_secondary(struct pt_regs *regs);
+
+static inline bool kdump_in_progress(void)
+{
+	return crashing_cpu >= 0;
 }
 
-static inline void reserve_crashkernel(void) { ; }
+bool is_kdump_kernel(void);
+#define is_kdump_kernel			is_kdump_kernel
+#if defined(CONFIG_PPC_RTAS)
+void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
+#define crash_free_reserved_phys_range crash_free_reserved_phys_range
+#endif /* CONFIG_PPC_RTAS */
+
+#else /* !CONFIG_CRASH_DUMP */
+static inline void crash_kexec_secondary(struct pt_regs *regs) { }
 
 static inline int crash_shutdown_register(crash_shutdown_t handler)
 {
@@ -183,7 +183,7 @@  static inline void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
 {
 }
 
-#endif /* CONFIG_KEXEC_CORE */
+#endif /* CONFIG_CRASH_DUMP */
 
 #ifdef CONFIG_PPC_BOOK3S_64
 #include <asm/book3s/64/kexec.h>
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 0b5878c3125b..1edc34b711ba 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -453,7 +453,7 @@  static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
 		tce_alloc_end = *lprop;
 #endif
 
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_RESERVE
 	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
 	if (lprop)
 		crashk_res.start = *lprop;
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 733f210ffda1..35cac3eaaf75 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -109,7 +109,7 @@  int ppc_do_canonicalize_irqs;
 EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
 #endif
 
-#ifdef CONFIG_VMCORE_INFO
+#ifdef CONFIG_CRASH_DUMP
 /* This keeps a track of which one is the crashing cpu. */
 int crashing_cpu = -1;
 #endif
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 693334c20d07..aa81c95c73a4 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -588,7 +588,7 @@  void smp_send_debugger_break(void)
 }
 #endif
 
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
 void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
 {
 	int cpu;
@@ -631,7 +631,7 @@  void crash_smp_send_stop(void)
 
 	stopped = true;
 
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
 	if (kexec_crash_image) {
 		crash_kexec_prepare();
 		return;
diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
index 91e96f5168b7..8e469c4da3f8 100644
--- a/arch/powerpc/kexec/Makefile
+++ b/arch/powerpc/kexec/Makefile
@@ -3,12 +3,13 @@ 
 # Makefile for the linux kernel.
 #
 
-obj-y				+= core.o crash.o core_$(BITS).o
+obj-y				+= core.o core_$(BITS).o
 
 obj-$(CONFIG_PPC32)		+= relocate_32.o
 
 obj-$(CONFIG_KEXEC_FILE)	+= file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o
 obj-$(CONFIG_VMCORE_INFO)	+= vmcore_info.o
+obj-$(CONFIG_CRASH_DUMP)	+= crash.o
 
 # Disable GCOV, KCOV & sanitizers in odd or sensitive code
 GCOV_PROFILE_core_$(BITS).o := n
diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c
index 3ff4411ed496..b8333a49ea5d 100644
--- a/arch/powerpc/kexec/core.c
+++ b/arch/powerpc/kexec/core.c
@@ -44,10 +44,12 @@  void machine_kexec_mask_interrupts(void) {
 	}
 }
 
+#ifdef CONFIG_CRASH_DUMP
 void machine_crash_shutdown(struct pt_regs *regs)
 {
 	default_machine_crash_shutdown(regs);
 }
+#endif
 
 void machine_kexec_cleanup(struct kimage *image)
 {
@@ -77,6 +79,7 @@  void machine_kexec(struct kimage *image)
 	for(;;);
 }
 
+#ifdef CONFIG_CRASH_RESERVE
 void __init reserve_crashkernel(void)
 {
 	unsigned long long crash_size, crash_base, total_mem_sz;
@@ -251,3 +254,4 @@  static int __init kexec_setup(void)
 	return 0;
 }
 late_initcall(kexec_setup);
+#endif /* CONFIG_CRASH_RESERVE */