path: root/Documentation/powerpc
diff options
authorHari Bathini <>2019-09-11 20:27:12 +0530
committerMichael Ellerman <>2019-09-14 00:04:45 +1000
commitb3bba79d5a7ba27bf7e31e124afbcb386128f2c6 (patch)
tree5a733dc169256d0d3b415df03f5ce5b6f597b7d1 /Documentation/powerpc
parent7b1b3b48250acbfd7f15ba950d4654b7f02a8300 (diff)
powerpc/fadump: update documentation about option to release opalcore
With /sys/firmware/opal/core support available on OPAL based machines and an option to the release memory used by kernel in exporting this core file, update FADump documentation with these details. Signed-off-by: Hari Bathini <> Signed-off-by: Michael Ellerman <> Link:
Diffstat (limited to 'Documentation/powerpc')
1 files changed, 19 insertions, 0 deletions
diff --git a/Documentation/powerpc/firmware-assisted-dump.rst b/Documentation/powerpc/firmware-assisted-dump.rst
index 08a9b5efcdc8..0455a78486d5 100644
--- a/Documentation/powerpc/firmware-assisted-dump.rst
+++ b/Documentation/powerpc/firmware-assisted-dump.rst
@@ -110,6 +110,16 @@ capture kernel boot to process this crash data. Kernel config
option CONFIG_PRESERVE_FA_DUMP has to be enabled on such kernel
to ensure that crash data is preserved to process later.
+-- On OPAL based machines (PowerNV), if the kernel is build with
+ CONFIG_OPAL_CORE=y, OPAL memory at the time of crash is also
+ exported as /sys/firmware/opal/core file. This procfs file is
+ helpful in debugging OPAL crashes with GDB. The kernel memory
+ used for exporting this procfs file can be released by echo'ing
+ '1' to /sys/kernel/fadump_release_opalcore node.
+ e.g.
+ # echo 1 > /sys/kernel/fadump_release_opalcore
Implementation details:
@@ -273,6 +283,15 @@ Here is the list of files under kernel sysfs:
enhanced to use this interface to release the memory reserved for
dump and continue without 2nd reboot.
+ /sys/kernel/fadump_release_opalcore
+ This file is available only on OPAL based machines when FADump is
+ active during capture kernel. This is used to release the memory
+ used by the kernel to export /sys/firmware/opal/core file. To
+ release this memory, echo '1' to it:
+ echo 1 > /sys/kernel/fadump_release_opalcore
Here is the list of files under powerpc debugfs:
(Assuming debugfs is mounted on /sys/kernel/debug directory.)