Re: [PATCH v2 RESEND 0/3] mm: memblock: fix debugfs flag reporting and synchronization
Mike Rapoport <[email protected]>
| Newsgroups | org.kvack.linux-mm,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Hi, On Fri, Aug 21, 2026 at 10:09:07AM +0800, Meijing Zhao wrote: > From: Meijing Zhao <[email protected]> > > The memblock debugfs interface has two issues when reporting region > flags. MEMBLOCK_RSRV_HUGETLB has no corresponding name, and regions > with multiple flags only show the lowest set bit. > > In addition, memblock_debug_show() walks the region arrays without > synchronizing against memory hotplug. If memory hotplug grows an array, > the debugfs reader may continue accessing the old array after it has > been freed. > > Add the missing HugeTLB flag name, report every set bit including those > beyond flagname[], and hold the memory hotplug read lock while walking > the arrays. > > With the series applied, a HugeTLB bootmem reservation is reported as: > > RSV_KERN|RSV_HUGETLB > > RESEND: > - Regenerate the series from the same clean base as v1. The previous v2 > was inadvertently generated with an unrelated MEMBLOCK_NODUMP change > in the patch context, causing apply failures. No code changes. I presume the changes were on top of linux-next and it's not clear how to apply them before the end of the merge window. Can you please resend the patches after v7.3-rc1 is out and base them on that? > Changes in v2: > - Report set bits beyond flagname[] as UNKNOWN instead of ignoring them. > - Add a separate patch to synchronize debugfs reads with memory hotplug. > > v1: https://lore.kernel.org/linux-mm/[email protected]/ > > Meijing Zhao (3): > mm: memblock: add missing HugeTLB flag name > mm: memblock: show all region flags in debugfs > mm: memblock: synchronize debugfs reads with memory hotplug > > mm/memblock.c | 26 ++++++++++++++++++-------- > 1 file changed, 18 insertions(+), 8 deletions(-) > > -- > 2.25.1 -- Sincerely yours, Mike.