fs/pstore/Kconfig - linux - Git at Google

 # SPDX-License-Identifier: GPL-2.0-only
 config PSTORE
 	tristate "Persistent store support"
 	default n
 	help
 	   This option enables generic access to platform level
 	   persistent storage via "pstore" filesystem that can
 	   be mounted as /dev/pstore.  Only useful if you have
 	   a platform level driver that registers with pstore to
 	   provide the data, so you probably should just go say "Y"
 	   (or "M") to a platform specific persistent store driver
 	   (e.g. ACPI_APEI on X86) which will select this for you.
 	   If you don't have a platform persistent store driver,
 	   say N.

 config PSTORE_DEFAULT_KMSG_BYTES
 	int "Default kernel log storage space" if EXPERT
 	depends on PSTORE
 	default "10240"
 	help
 	  Defines default size of pstore kernel log storage.
 	  Can be enlarged if needed, not recommended to shrink it.

 config PSTORE_COMPRESS
 	bool "Pstore compression (deflate)"
 	depends on PSTORE
 	select ZLIB_INFLATE
 	select ZLIB_DEFLATE
 	default y
 	help
 	  Whether pstore records should be compressed before being written to
 	  the backing store. This is implemented using the zlib 'deflate'
 	  algorithm, using the library implementation instead of using the full
 	  blown crypto API. This reduces the risk of secondary oopses or other
 	  problems while pstore is recording panic metadata.

 config PSTORE_CONSOLE
 	bool "Log kernel console messages"
 	depends on PSTORE
 	help
 	  When the option is enabled, pstore will log all kernel
 	  messages, even if no oops or panic happened.

 config PSTORE_PMSG
 	bool "Log user space messages"
 	depends on PSTORE
 	select RT_MUTEXES
 	help
 	  When the option is enabled, pstore will export a character
 	  interface /dev/pmsg0 to log user space messages. On reboot
 	  data can be retrieved from /sys/fs/pstore/pmsg-ramoops-[ID].

 	  If unsure, say N.

 config PSTORE_FTRACE
 	bool "Persistent function tracer"
 	depends on PSTORE
 	depends on FUNCTION_TRACER
 	depends on DEBUG_FS
 	help
 	  With this option kernel traces function calls into a persistent
 	  ram buffer that can be decoded and dumped after reboot through
 	  pstore filesystem. It can be used to determine what function
 	  was last called before a reset or panic.

 	  If unsure, say N.

 config PSTORE_RAM
 	tristate "Log panic/oops to a RAM buffer"
 	depends on PSTORE
 	depends on HAS_IOMEM
 	select REED_SOLOMON
 	select REED_SOLOMON_ENC8
 	select REED_SOLOMON_DEC8
 	help
 	  This enables panic and oops messages to be logged to a circular
 	  buffer in RAM where it can be read back at some later point.

 	  Note that for historical reasons, the module will be named
 	  "ramoops.ko".

 	  For more information, see Documentation/admin-guide/ramoops.rst.

 config PSTORE_ZONE
 	tristate
 	depends on PSTORE
 	help
 	  The common layer for pstore/blk (and pstore/ram in the future)
 	  to manage storage in zones.

 config PSTORE_BLK
 	tristate "Log panic/oops to a block device"
 	depends on PSTORE
 	depends on BLOCK
 	select PSTORE_ZONE
 	default n
 	help
 	  This enables panic and oops message to be logged to a block dev
 	  where it can be read back at some later point.

 	  For more information, see Documentation/admin-guide/pstore-blk.rst

 	  If unsure, say N.

 config PSTORE_BLK_BLKDEV
 	string "block device identifier"
 	depends on PSTORE_BLK
 	default ""
 	help
 	  Which block device should be used for pstore/blk.

 	  It accepts the following variants:
 	  1) <hex_major><hex_minor> device number in hexadecimal representation,
 	     with no leading 0x, for example b302.
 	  2) /dev/<disk_name> represents the device name of disk
 	  3) /dev/<disk_name><decimal> represents the device name and number
 	     of partition - device number of disk plus the partition number
 	  4) /dev/<disk_name>p<decimal> - same as the above, this form is
 	     used when disk name of partitioned disk ends with a digit.
 	  5) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
 	     unique id of a partition if the partition table provides it.
 	     The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
 	     partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
 	     filled hex representation of the 32-bit "NT disk signature", and PP
 	     is a zero-filled hex representation of the 1-based partition number.
 	  6) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation
 	     to a partition with a known unique id.
 	  7) <major>:<minor> major and minor number of the device separated by
 	     a colon.

 	  NOTE that, both Kconfig and module parameters can configure
 	  pstore/blk, but module parameters have priority over Kconfig.

 config PSTORE_BLK_KMSG_SIZE
 	int "Size in Kbytes of kmsg dump log to store"
 	depends on PSTORE_BLK
 	default 64
 	help
 	  This just sets size of kmsg dump (oops, panic, etc) log for
 	  pstore/blk. The size is in KB and must be a multiple of 4.

 	  NOTE that, both Kconfig and module parameters can configure
 	  pstore/blk, but module parameters have priority over Kconfig.

 config PSTORE_BLK_MAX_REASON
 	int "Maximum kmsg dump reason to store"
 	depends on PSTORE_BLK
 	default 2
 	help
 	  The maximum reason for kmsg dumps to store. The default is
 	  2 (KMSG_DUMP_OOPS), see include/linux/kmsg_dump.h's
 	  enum kmsg_dump_reason for more details.

 	  NOTE that, both Kconfig and module parameters can configure
 	  pstore/blk, but module parameters have priority over Kconfig.

 config PSTORE_BLK_PMSG_SIZE
 	int "Size in Kbytes of pmsg to store"
 	depends on PSTORE_BLK
 	depends on PSTORE_PMSG
 	default 64
 	help
 	  This just sets size of pmsg (pmsg_size) for pstore/blk. The size is
 	  in KB and must be a multiple of 4.

 	  NOTE that, both Kconfig and module parameters can configure
 	  pstore/blk, but module parameters have priority over Kconfig.

 config PSTORE_BLK_CONSOLE_SIZE
 	int "Size in Kbytes of console log to store"
 	depends on PSTORE_BLK
 	depends on PSTORE_CONSOLE
 	default 64
 	help
 	  This just sets size of console log (console_size) to store via
 	  pstore/blk. The size is in KB and must be a multiple of 4.

 	  NOTE that, both Kconfig and module parameters can configure
 	  pstore/blk, but module parameters have priority over Kconfig.

 config PSTORE_BLK_FTRACE_SIZE
 	int "Size in Kbytes of ftrace log to store"
 	depends on PSTORE_BLK
 	depends on PSTORE_FTRACE
 	default 64
 	help
 	  This just sets size of ftrace log (ftrace_size) for pstore/blk. The
 	  size is in KB and must be a multiple of 4.

 	  NOTE that, both Kconfig and module parameters can configure
 	  pstore/blk, but module parameters have priority over Kconfig.
	# SPDX-License-Identifier: GPL-2.0-only
	config PSTORE
	tristate "Persistent store support"
	default n
	help
	This option enables generic access to platform level
	persistent storage via "pstore" filesystem that can
	be mounted as /dev/pstore. Only useful if you have
	a platform level driver that registers with pstore to
	provide the data, so you probably should just go say "Y"
	(or "M") to a platform specific persistent store driver
	(e.g. ACPI_APEI on X86) which will select this for you.
	If you don't have a platform persistent store driver,
	say N.

	config PSTORE_DEFAULT_KMSG_BYTES
	int "Default kernel log storage space" if EXPERT
	depends on PSTORE
	default "10240"
	help
	Defines default size of pstore kernel log storage.
	Can be enlarged if needed, not recommended to shrink it.

	config PSTORE_COMPRESS
	bool "Pstore compression (deflate)"
	depends on PSTORE
	select ZLIB_INFLATE
	select ZLIB_DEFLATE
	default y
	help
	Whether pstore records should be compressed before being written to
	the backing store. This is implemented using the zlib 'deflate'
	algorithm, using the library implementation instead of using the full
	blown crypto API. This reduces the risk of secondary oopses or other
	problems while pstore is recording panic metadata.

	config PSTORE_CONSOLE
	bool "Log kernel console messages"
	depends on PSTORE
	help
	When the option is enabled, pstore will log all kernel
	messages, even if no oops or panic happened.

	config PSTORE_PMSG
	bool "Log user space messages"
	depends on PSTORE
	select RT_MUTEXES
	help
	When the option is enabled, pstore will export a character
	interface /dev/pmsg0 to log user space messages. On reboot
	data can be retrieved from /sys/fs/pstore/pmsg-ramoops-[ID].

	If unsure, say N.

	config PSTORE_FTRACE
	bool "Persistent function tracer"
	depends on PSTORE
	depends on FUNCTION_TRACER
	depends on DEBUG_FS
	help
	With this option kernel traces function calls into a persistent
	ram buffer that can be decoded and dumped after reboot through
	pstore filesystem. It can be used to determine what function
	was last called before a reset or panic.

	If unsure, say N.

	config PSTORE_RAM
	tristate "Log panic/oops to a RAM buffer"
	depends on PSTORE
	depends on HAS_IOMEM
	select REED_SOLOMON
	select REED_SOLOMON_ENC8
	select REED_SOLOMON_DEC8
	help
	This enables panic and oops messages to be logged to a circular
	buffer in RAM where it can be read back at some later point.

	Note that for historical reasons, the module will be named
	"ramoops.ko".

	For more information, see Documentation/admin-guide/ramoops.rst.

	config PSTORE_ZONE
	tristate
	depends on PSTORE
	help
	The common layer for pstore/blk (and pstore/ram in the future)
	to manage storage in zones.

	config PSTORE_BLK
	tristate "Log panic/oops to a block device"
	depends on PSTORE
	depends on BLOCK
	select PSTORE_ZONE
	default n
	help
	This enables panic and oops message to be logged to a block dev
	where it can be read back at some later point.

	For more information, see Documentation/admin-guide/pstore-blk.rst

	If unsure, say N.

	config PSTORE_BLK_BLKDEV
	string "block device identifier"
	depends on PSTORE_BLK
	default ""
	help
	Which block device should be used for pstore/blk.

	It accepts the following variants:
	1) <hex_major><hex_minor> device number in hexadecimal representation,
	with no leading 0x, for example b302.
	2) /dev/<disk_name> represents the device name of disk
	3) /dev/<disk_name><decimal> represents the device name and number
	of partition - device number of disk plus the partition number
	4) /dev/<disk_name>p<decimal> - same as the above, this form is
	used when disk name of partitioned disk ends with a digit.
	5) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
	unique id of a partition if the partition table provides it.
	The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
	partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
	filled hex representation of the 32-bit "NT disk signature", and PP
	is a zero-filled hex representation of the 1-based partition number.
	6) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation
	to a partition with a known unique id.
	7) <major>:<minor> major and minor number of the device separated by
	a colon.

	NOTE that, both Kconfig and module parameters can configure
	pstore/blk, but module parameters have priority over Kconfig.

	config PSTORE_BLK_KMSG_SIZE
	int "Size in Kbytes of kmsg dump log to store"
	depends on PSTORE_BLK
	default 64
	help
	This just sets size of kmsg dump (oops, panic, etc) log for
	pstore/blk. The size is in KB and must be a multiple of 4.

	NOTE that, both Kconfig and module parameters can configure
	pstore/blk, but module parameters have priority over Kconfig.

	config PSTORE_BLK_MAX_REASON
	int "Maximum kmsg dump reason to store"
	depends on PSTORE_BLK
	default 2
	help
	The maximum reason for kmsg dumps to store. The default is
	2 (KMSG_DUMP_OOPS), see include/linux/kmsg_dump.h's
	enum kmsg_dump_reason for more details.

	NOTE that, both Kconfig and module parameters can configure
	pstore/blk, but module parameters have priority over Kconfig.

	config PSTORE_BLK_PMSG_SIZE
	int "Size in Kbytes of pmsg to store"
	depends on PSTORE_BLK
	depends on PSTORE_PMSG
	default 64
	help
	This just sets size of pmsg (pmsg_size) for pstore/blk. The size is
	in KB and must be a multiple of 4.

	NOTE that, both Kconfig and module parameters can configure
	pstore/blk, but module parameters have priority over Kconfig.

	config PSTORE_BLK_CONSOLE_SIZE
	int "Size in Kbytes of console log to store"
	depends on PSTORE_BLK
	depends on PSTORE_CONSOLE
	default 64
	help
	This just sets size of console log (console_size) to store via
	pstore/blk. The size is in KB and must be a multiple of 4.

	NOTE that, both Kconfig and module parameters can configure
	pstore/blk, but module parameters have priority over Kconfig.

	config PSTORE_BLK_FTRACE_SIZE
	int "Size in Kbytes of ftrace log to store"
	depends on PSTORE_BLK
	depends on PSTORE_FTRACE
	default 64
	help
	This just sets size of ftrace log (ftrace_size) for pstore/blk. The
	size is in KB and must be a multiple of 4.

	NOTE that, both Kconfig and module parameters can configure
	pstore/blk, but module parameters have priority over Kconfig.