diff options
| author | Sourabh Jain <sourabhjain@linux.ibm.com> | 2025-11-07 13:33:34 +0530 |
|---|---|---|
| committer | Madhavan Srinivasan <maddy@linux.ibm.com> | 2025-11-11 14:11:08 +0530 |
| commit | b4a96ab50f368afc2360ff539a20254ca2c9a889 (patch) | |
| tree | 11c05cb190dc8eb962d2d5b9058990e5bba4b935 /Documentation/admin-guide/kernel-parameters.txt | |
| parent | 8127c4fdf169465b631b62f7e45a042ced32dc77 (diff) | |
powerpc/kdump: Add support for crashkernel CMA reservation
Commit 35c18f2933c5 ("Add a new optional ",cma" suffix to the
crashkernel= command line option") and commit ab475510e042 ("kdump:
implement reserve_crashkernel_cma") added CMA support for kdump
crashkernel reservation.
Extend crashkernel CMA reservation support to powerpc.
The following changes are made to enable CMA reservation on powerpc:
- Parse and obtain the CMA reservation size along with other crashkernel
parameters
- Call reserve_crashkernel_cma() to allocate the CMA region for kdump
- Include the CMA-reserved ranges in the usable memory ranges for the
kdump kernel to use.
- Exclude the CMA-reserved ranges from the crash kernel memory to
prevent them from being exported through /proc/vmcore.
With the introduction of the CMA crashkernel regions,
crash_exclude_mem_range() needs to be called multiple times to exclude
both crashk_res and crashk_cma_ranges from the crash memory ranges. To
avoid repetitive logic for validating mem_ranges size and handling
reallocation when required, this functionality is moved to a new wrapper
function crash_exclude_mem_range_guarded().
To ensure proper CMA reservation, reserve_crashkernel_cma() is called
after pageblock_order is initialized.
Update kernel-parameters.txt to document CMA support for crashkernel on
powerpc architecture.
Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20251107080334.708028-1-sourabhjain@linux.ibm.com
Diffstat (limited to 'Documentation/admin-guide/kernel-parameters.txt')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6c42061ca20e..1c10190d583d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1013,7 +1013,7 @@ It will be ignored when crashkernel=X,high is not used or memory reserved is below 4G. crashkernel=size[KMG],cma - [KNL, X86] Reserve additional crash kernel memory from + [KNL, X86, ppc] Reserve additional crash kernel memory from CMA. This reservation is usable by the first system's userspace memory and kernel movable allocations (memory balloon, zswap). Pages allocated from this memory range |