Lines Matching +full:os +full:- +full:data +full:- +full:offset
2 Firmware-Assisted Dump
7 The goal of firmware-assisted dump is to enable the dump of
8 a crashed system, and to do so from a fully-reset system, and
12 - Firmware-Assisted Dump (FADump) infrastructure is intended to replace
14 - Fadump uses the same firmware interfaces and memory reservation model
16 - Unlike phyp dump, FADump exports the memory dump through /proc/vmcore
19 - Unlike phyp dump, userspace tool does not need to refer any sysfs
21 - Unlike phyp dump, FADump allows user to release all the memory reserved
23 - Once enabled through kernel boot parameter, FADump can be
28 Comparing with kdump or other strategies, firmware-assisted
31 - Unlike kdump, the system has been reset, and loaded
35 - Once the dump is copied out, the memory that held the dump
44 - The first kernel registers the sections of memory with the
45 Power firmware for dump preservation during OS initialization.
49 - When system crashes, the Power firmware will copy the registered
63 refer to Documentation/admin-guide/kdump/kdump.rst. If any
64 offset is provided in crashkernel= parameter, it will be
65 ignored as FADump uses a predefined offset to reserve memory
68 - After the low memory (boot memory) area has been saved, the
73 - The freshly booted kernel will notice that there is a new node
74 (rtas/ibm,kernel-dump on pSeries or ibm,opal/dump/mpipl-boot
76 there is crash data available from a previous boot. During
77 the early boot OS will reserve rest of the memory above
83 - User-space tools will read /proc/vmcore to obtain the contents
88 - Once the userspace tool is done saving dump, it will echo
91 next firmware-assisted dump registration.
97 Please note that the firmware-assisted dump feature
107 userspace support to process crash data. Such kernel needs to
109 capture kernel boot to process this crash data. Kernel config
111 to ensure that crash data is preserved to process later.
113 -- On OPAL based machines (PowerNV), if the kernel is build with
124 -----------------------
132 that are run. If there is dump data, then the
136 If there is no waiting dump data, then only the memory required to
138 usually reserved at an offset greater than boot memory size (see Fig. 1).
157 0 boot memory size |<------ Reserved dump area ----->| |
160 +-----------+-----/ /---+---+----+-----------+-------+----+-----+
162 +-----------+-----/ /---+---+----+-----------+-------+----+-----+
166 -------------------------------- | |
187 | |<------------ Crash preserved area ------------>|
188 V V |<--- Reserved dump area --->| |
189 +----+---+--+-----/ /---+---+----+-------+-----+-----+-------+
191 +----+---+--+-----/ /---+---+----+-------+-----+-----+-------+
193 ----- ------------------------------ ---------------
197 \ | ----------------------------
204 +---+
205 |///| -> Regions (CPU, HPTE & Metadata) marked like this in the above
206 +---+ figures are not always present. For example, OPAL platform
210 +---+
211 |ELF| -> elfcorehdr, it is created in second kernel after crash.
212 +---+
220 user intervention. The dump data available through /proc/vmcore will be
230 How to enable firmware-assisted dump (FADump):
231 ----------------------------------------------
246 2. If firmware-assisted dump fails to reserve memory then it
255 --------------------
257 Firmware-assisted dump feature uses sysfs file system to hold
265 - 0 = FADump is disabled
266 - 1 = FADump is enabled
275 - 0 = FADump is not registered.
276 - 1 = FADump is registered and ready to handle system crash.
279 echo 0 > /sys/kernel/fadump_registered for un-register and stop the
280 FADump. Once the FADump is un-registered, the system crash will not
318 +----------------------------------+--------------------------------+
320 +----------------------------------+--------------------------------+
322 +----------------------------------+--------------------------------+
324 +----------------------------------+--------------------------------+
326 +----------------------------------+--------------------------------+
336 <region>: [<start>-<end>] <reserved-size> bytes, Dumped: <dump-size>
340 DUMP: Src: <src-addr>, Dest: <dest-addr>, Size: <size>, Dumped: # bytes
346 CPU : [0x0000006ffb0000-0x0000006fff001f] 0x40020 bytes, Dumped: 0x0
347 HPTE: [0x0000006fff0020-0x0000006fff101f] 0x1000 bytes, Dumped: 0x0
348 DUMP: [0x0000006fff1020-0x0000007fff101f] 0x10000000 bytes, Dumped: 0x0
353 CPU : [0x0000006ffb0000-0x0000006fff001f] 0x40020 bytes, Dumped: 0x40020
354 HPTE: [0x0000006fff0020-0x0000006fff101f] 0x1000 bytes, Dumped: 0x1000
355 DUMP: [0x0000006fff1020-0x0000007fff101f] 0x10000000 bytes, Dumped: 0x10000000
356 : [0x00000010000000-0x0000006ffaffff] 0x5ffb0000 bytes, Dumped: 0x5ffb0000
365 -----
366 - Need to come up with the better approach to find out more