Hello Mahesh,
On 26/01/25 17:31, Mahesh J Salgaonkar wrote:
On 2025-01-23 17:12:54 Thu, Sourabh Jain wrote:
Update the fadump document to include details about the fadump
additional parameter feature.
The document includes the following:
- Significance of the feature
- How to use it
- Feature restrictions
No functional changes are introduced.
Cc: Avnish Chouhan <avn...@linux.ibm.com>
Cc: Brian King <brk...@linux.ibm.com>
Cc: Hari Bathini <hbath...@linux.ibm.com>
Cc: Madhavan Srinivasan <ma...@linux.ibm.com>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Mahesh Salgaonkar <mah...@linux.ibm.com>
Signed-off-by: Sourabh Jain <sourabhj...@linux.ibm.com>
---
Documentation/ABI/testing/sysfs-kernel-fadump | 3 ++-
.../arch/powerpc/firmware-assisted-dump.rst | 22 +++++++++++++++++++
2 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump
b/Documentation/ABI/testing/sysfs-kernel-fadump
index 2f9daa7ca55b..b64b7622e6fc 100644
--- a/Documentation/ABI/testing/sysfs-kernel-fadump
+++ b/Documentation/ABI/testing/sysfs-kernel-fadump
[...]
+-- Support for Additional Kernel Arguments in Fadump
+ Fadump has a feature that allows passing additional kernel arguments
+ to the fadump kernel. This feature was primarily designed to disable
+ kernel functionalities that are not required for the fadump kernel
+ and to reduce its memory footprint while collecting the dump.
+
+ Command to Add Additional Kernel Parameters to Fadump:
+ e.g.
+ # echo "nr_cpus=16" > /sys/kernel/fadump/bootargs_append
+
+ The above command is sufficient to add additional arguments to fadump.
+ An explicit service restart is not required.
+
+ Command to Retrieve the Additional Fadump Arguments:
+ e.g.
+ # cat /sys/kernel/fadump/bootargs_append
+
+Note: Additional kernel arguments for fadump with HASH MMU is only
+ supported if the RMA size is greater than 768 MB. If the RMA
+ size is less than 768 MB, the kernel does not export the
+ /sys/kernel/fadump/bootargs_append sysfs node.
Reviewed-by: Mahesh Salgaonkar <mah...@linux.ibm.com>
Thanks for the review.
- Sourabh Jain
