1# SPDX-License-Identifier: GPL-2.0-only
2config PSTORE
3	tristate "Persistent store support"
4	default n
5	help
6	   This option enables generic access to platform level
7	   persistent storage via "pstore" filesystem that can
8	   be mounted as /dev/pstore.  Only useful if you have
9	   a platform level driver that registers with pstore to
10	   provide the data, so you probably should just go say "Y"
11	   (or "M") to a platform specific persistent store driver
12	   (e.g. ACPI_APEI on X86) which will select this for you.
13	   If you don't have a platform persistent store driver,
14	   say N.
15
16config PSTORE_DEFAULT_KMSG_BYTES
17	int "Default kernel log storage space" if EXPERT
18	depends on PSTORE
19	default "10240"
20	help
21	  Defines default size of pstore kernel log storage.
22	  Can be enlarged if needed, not recommended to shrink it.
23
24config PSTORE_COMPRESS
25	bool "Pstore compression (deflate)"
26	depends on PSTORE
27	select ZLIB_INFLATE
28	select ZLIB_DEFLATE
29	default y
30	help
31	  Whether pstore records should be compressed before being written to
32	  the backing store. This is implemented using the zlib 'deflate'
33	  algorithm, using the library implementation instead of using the full
34	  blown crypto API. This reduces the risk of secondary oopses or other
35	  problems while pstore is recording panic metadata.
36
37config PSTORE_CONSOLE
38	bool "Log kernel console messages"
39	depends on PSTORE
40	help
41	  When the option is enabled, pstore will log all kernel
42	  messages, even if no oops or panic happened.
43
44config PSTORE_PMSG
45	bool "Log user space messages"
46	depends on PSTORE
47	select RT_MUTEXES
48	help
49	  When the option is enabled, pstore will export a character
50	  interface /dev/pmsg0 to log user space messages. On reboot
51	  data can be retrieved from /sys/fs/pstore/pmsg-ramoops-[ID].
52
53	  If unsure, say N.
54
55config PSTORE_FTRACE
56	bool "Persistent function tracer"
57	depends on PSTORE
58	depends on FUNCTION_TRACER
59	depends on DEBUG_FS
60	help
61	  With this option kernel traces function calls into a persistent
62	  ram buffer that can be decoded and dumped after reboot through
63	  pstore filesystem. It can be used to determine what function
64	  was last called before a reset or panic.
65
66	  If unsure, say N.
67
68config PSTORE_RAM
69	tristate "Log panic/oops to a RAM buffer"
70	depends on PSTORE
71	depends on HAS_IOMEM
72	select REED_SOLOMON
73	select REED_SOLOMON_ENC8
74	select REED_SOLOMON_DEC8
75	help
76	  This enables panic and oops messages to be logged to a circular
77	  buffer in RAM where it can be read back at some later point.
78
79	  Note that for historical reasons, the module will be named
80	  "ramoops.ko".
81
82	  For more information, see Documentation/admin-guide/ramoops.rst.
83
84config PSTORE_ZONE
85	tristate
86	depends on PSTORE
87	help
88	  The common layer for pstore/blk (and pstore/ram in the future)
89	  to manage storage in zones.
90
91config PSTORE_BLK
92	tristate "Log panic/oops to a block device"
93	depends on PSTORE
94	depends on BLOCK
95	select PSTORE_ZONE
96	default n
97	help
98	  This enables panic and oops message to be logged to a block dev
99	  where it can be read back at some later point.
100
101	  For more information, see Documentation/admin-guide/pstore-blk.rst
102
103	  If unsure, say N.
104
105config PSTORE_BLK_BLKDEV
106	string "block device identifier"
107	depends on PSTORE_BLK
108	default ""
109	help
110	  Which block device should be used for pstore/blk.
111
112	  It accepts the following variants:
113	  1) <hex_major><hex_minor> device number in hexadecimal representation,
114	     with no leading 0x, for example b302.
115	  2) /dev/<disk_name> represents the device name of disk
116	  3) /dev/<disk_name><decimal> represents the device name and number
117	     of partition - device number of disk plus the partition number
118	  4) /dev/<disk_name>p<decimal> - same as the above, this form is
119	     used when disk name of partitioned disk ends with a digit.
120	  5) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
121	     unique id of a partition if the partition table provides it.
122	     The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
123	     partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
124	     filled hex representation of the 32-bit "NT disk signature", and PP
125	     is a zero-filled hex representation of the 1-based partition number.
126	  6) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation
127	     to a partition with a known unique id.
128	  7) <major>:<minor> major and minor number of the device separated by
129	     a colon.
130
131	  NOTE that, both Kconfig and module parameters can configure
132	  pstore/blk, but module parameters have priority over Kconfig.
133
134config PSTORE_BLK_KMSG_SIZE
135	int "Size in Kbytes of kmsg dump log to store"
136	depends on PSTORE_BLK
137	default 64
138	help
139	  This just sets size of kmsg dump (oops, panic, etc) log for
140	  pstore/blk. The size is in KB and must be a multiple of 4.
141
142	  NOTE that, both Kconfig and module parameters can configure
143	  pstore/blk, but module parameters have priority over Kconfig.
144
145config PSTORE_BLK_MAX_REASON
146	int "Maximum kmsg dump reason to store"
147	depends on PSTORE_BLK
148	default 2
149	help
150	  The maximum reason for kmsg dumps to store. The default is
151	  2 (KMSG_DUMP_OOPS), see include/linux/kmsg_dump.h's
152	  enum kmsg_dump_reason for more details.
153
154	  NOTE that, both Kconfig and module parameters can configure
155	  pstore/blk, but module parameters have priority over Kconfig.
156
157config PSTORE_BLK_PMSG_SIZE
158	int "Size in Kbytes of pmsg to store"
159	depends on PSTORE_BLK
160	depends on PSTORE_PMSG
161	default 64
162	help
163	  This just sets size of pmsg (pmsg_size) for pstore/blk. The size is
164	  in KB and must be a multiple of 4.
165
166	  NOTE that, both Kconfig and module parameters can configure
167	  pstore/blk, but module parameters have priority over Kconfig.
168
169config PSTORE_BLK_CONSOLE_SIZE
170	int "Size in Kbytes of console log to store"
171	depends on PSTORE_BLK
172	depends on PSTORE_CONSOLE
173	default 64
174	help
175	  This just sets size of console log (console_size) to store via
176	  pstore/blk. The size is in KB and must be a multiple of 4.
177
178	  NOTE that, both Kconfig and module parameters can configure
179	  pstore/blk, but module parameters have priority over Kconfig.
180
181config PSTORE_BLK_FTRACE_SIZE
182	int "Size in Kbytes of ftrace log to store"
183	depends on PSTORE_BLK
184	depends on PSTORE_FTRACE
185	default 64
186	help
187	  This just sets size of ftrace log (ftrace_size) for pstore/blk. The
188	  size is in KB and must be a multiple of 4.
189
190	  NOTE that, both Kconfig and module parameters can configure
191	  pstore/blk, but module parameters have priority over Kconfig.
192