[PATCH 0/3] mm/vmalloc: fix vmalloc_dump_obj VA lookup
From: Ye Liu
Date: Wed Sep 16 2026 - 04:28:46 EST
vmalloc_dump_obj() has two bugs that cause it to miss vmalloc
allocations, plus a minor optimization opportunity:
1. PAGE_ALIGN() rounds up, pushing last-page addresses to va_end
and outside the VA lookup range.
2. The function searches only one vmap node, but allocations
larger than 64 KiB may span multiple vmap zones whose VA
is stored in a different node's rb-tree.
Patch 1 fixes the alignment, patch 2 fixes the cross-zone search,
patch 3 adds an early is_vmalloc_addr() check to skip non-vmalloc
addresses without traversing all nodes.
Signed-off-by: Ye Liu <liuye@xxxxxxxxxx>
---
Ye Liu (3):
mm/vmalloc: fix vmalloc_dump_obj address alignment for last-page lookups
mm/vmalloc: fix vmalloc_dump_obj cross-zone VA lookup
mm/vmalloc: skip vmalloc_dump_obj for non-vmalloc addresses
mm/vmalloc.c | 29 ++++++++++++++++++++++-------
1 file changed, 22 insertions(+), 7 deletions(-)
---
base-commit: e6e35979777d646fe3c7c94dca7dd32fb25d45f4
change-id: 20260916-vmalloc_dump_obj-d80908447369
Best regards,
--
Ye Liu <ye.liu@xxxxxxxxx>