include/linux/memblock.h | 21 +++++++++- kernel/liveupdate/Kconfig | 2 - kernel/liveupdate/kexec_handover.c | 52 ++++++++++++------------- mm/memblock.c | 56 +++++++++++---------------- mm/mm_init.c | 30 +++++++------- tools/testing/selftests/kho/vmtest.sh | 4 ++ 6 files changed, 88 insertions(+), 77 deletions(-)
When CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, struct page initialization is deferred to parallel kthreads that run later in the boot process. Currently, KHO is incompatible with DEFERRED. This series fixes that incompatibility. --- v9: - moved init_pageblock_migratetype from memmap_init_reserved_range to __init_page_from_nid - reduced number of ifdefs - new commit to test this feature v8: - moved overriding the migratetype from init_pageblock_migratetype to callsites v7: - reimplemented the initialization of kho scratch again v6: - reimplemented the initialization of kho scratch v5: - rebased v4: - added a new commit to fix deferred init of kho scratch - switched to ulong when refering to pfn v3: - changed commit msg - don't invoke early_pfn_to_nid if CONFIG_DEFERRED_STRUCT_PAGE_INIT=n v2: - updated a comment I took Evangelos's test code: https://git.infradead.org/?p=users/vpetrog/linux.git;a=shortlog;h=refs/heads/kho-deferred-struct-page-init and then modified it to this monster test that does 2 allocations: at core_initcall (early) and at module_init (late). Then kexec, then 2 more allocations at these points, then restore the original 2, then kexec, then restore the other 2. Basically I test preservation of early and late allocation both on cold and on warm boot. Tested it both with and without DEFERRED. https://github.com/mclapinski/linux/commits/deferred_test/ This patch probably doesn't apply onto anything currently. It's based on mm-new with "memblock: move reserve_bootmem_range() to memblock.c and make it static" cherrypicked from rppt/memblock. Evangelos Petrongonas (1): kho: make preserved pages compatible with deferred struct page init Michal Clapinski (2): kho: fix deferred initialization of scratch areas selftests: kho: test with deferred struct page init include/linux/memblock.h | 21 +++++++++- kernel/liveupdate/Kconfig | 2 - kernel/liveupdate/kexec_handover.c | 52 ++++++++++++------------- mm/memblock.c | 56 +++++++++++---------------- mm/mm_init.c | 30 +++++++------- tools/testing/selftests/kho/vmtest.sh | 4 ++ 6 files changed, 88 insertions(+), 77 deletions(-) -- 2.54.0.rc2.533.g4f5dca5207-goog
Hi Michal, On Thu, Apr 23, 2026 at 02:25:35PM +0200, Michal Clapinski wrote: > When CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, struct page > initialization is deferred to parallel kthreads that run later in > the boot process. This patchset breaks memblock tests: https://github.com/linux-mm/linux-mm/actions/runs/25259346624/job/74063911769 Can you please send a fix? > Michal Clapinski (2): > kho: fix deferred initialization of scratch areas > selftests: kho: test with deferred struct page init > > include/linux/memblock.h | 21 +++++++++- > kernel/liveupdate/Kconfig | 2 - > kernel/liveupdate/kexec_handover.c | 52 ++++++++++++------------- > mm/memblock.c | 56 +++++++++++---------------- > mm/mm_init.c | 30 +++++++------- > tools/testing/selftests/kho/vmtest.sh | 4 ++ > 6 files changed, 88 insertions(+), 77 deletions(-) > > -- > 2.54.0.rc2.533.g4f5dca5207-goog > -- Sincerely yours, Mike.
On Sun, May 03 2026, Mike Rapoport wrote:
> Hi Michal,
>
> On Thu, Apr 23, 2026 at 02:25:35PM +0200, Michal Clapinski wrote:
>> When CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, struct page
>> initialization is deferred to parallel kthreads that run later in
>> the boot process.
>
> This patchset breaks memblock tests:
> https://github.com/linux-mm/linux-mm/actions/runs/25259346624/job/74063911769
>
> Can you please send a fix?
Would something like this do the trick? It fixes the build for me and
the tests pass.
I can send this as a proper patch if this looks good.
--- 8< ---
diff --git a/tools/testing/memblock/linux/mmzone.h b/tools/testing/memblock/linux/mmzone.h
index bb682659a12d..8d934ff5b080 100644
--- a/tools/testing/memblock/linux/mmzone.h
+++ b/tools/testing/memblock/linux/mmzone.h
@@ -35,4 +35,8 @@ typedef struct pglist_data {
} pg_data_t;
+enum migratetype {
+ MIGRATE_CMA,
+};
+
#endif
--
Regards,
Pratyush Yadav
On Mon, May 04, 2026 at 09:53:01AM +0200, Pratyush Yadav wrote:
> On Sun, May 03 2026, Mike Rapoport wrote:
>
> > Hi Michal,
> >
> > On Thu, Apr 23, 2026 at 02:25:35PM +0200, Michal Clapinski wrote:
> >> When CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, struct page
> >> initialization is deferred to parallel kthreads that run later in
> >> the boot process.
> >
> > This patchset breaks memblock tests:
> > https://github.com/linux-mm/linux-mm/actions/runs/25259346624/job/74063911769
> >
> > Can you please send a fix?
>
> Would something like this do the trick? It fixes the build for me and
> the tests pass.
>
> I can send this as a proper patch if this looks good.
Yes, please :)
> --- 8< ---
> diff --git a/tools/testing/memblock/linux/mmzone.h b/tools/testing/memblock/linux/mmzone.h
> index bb682659a12d..8d934ff5b080 100644
> --- a/tools/testing/memblock/linux/mmzone.h
> +++ b/tools/testing/memblock/linux/mmzone.h
> @@ -35,4 +35,8 @@ typedef struct pglist_data {
>
> } pg_data_t;
>
> +enum migratetype {
> + MIGRATE_CMA,
> +};
> +
> #endif
> --
> Regards,
> Pratyush Yadav
--
Sincerely yours,
Mike.
From: Mike Rapoport (Microsoft) <rppt@kernel.org>
On Thu, 23 Apr 2026 14:25:35 +0200, Michal Clapinski wrote:
> When CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, struct page
> initialization is deferred to parallel kthreads that run later in
> the boot process.
>
> Currently, KHO is incompatible with DEFERRED.
> This series fixes that incompatibility.
>
> [...]
Applied to next branch of liveupdate/linux.git tree, thanks!
[1/3] kho: fix deferred initialization of scratch areas
commit: fe60961059eee7a3a303454c827bb347c45612c1
[2/3] kho: make preserved pages compatible with deferred struct page init
commit: d4835433f4f6b5d618955a6a6eeb3e9f8b2b725e
[3/3] selftests: kho: test with deferred struct page init
commit: eee13213401bafb7ffe3b447adffb1f570b9d813
tree: https://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux
branch: next
--
Sincerely yours,
Mike.
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