[PATCH v2 0/5] of: reserved_mem: several fixes about reserved memory

[Wandun Chen]

From: Wandun Chen <chenwandun@xxxxxxxxxxx>

This series fixes several error-handling issues in the reserved-memory
initialization paths.

Static reserved-memory nodes are reserved during the early DT scan but
initialized later. The first patch prevents a node whose early
reservation failed from reaching the late initialization path.

The following two patches reject overlapping static regions. Without
these checks, overlapping nodes can be initialized over the same
physical memory, result in data corrupt.

The last two patches fix cleanup of no-map regions after driver.

Sashiko reported these issues in [1] [2] [3].

[1] https://sashiko.dev/#/message/20260814090305.4C8741F00A3D%40smtp.kernel.org
[2] https://sashiko.dev/#/message/20260814084718.29C341F000E9%40smtp.kernel.org
[3] https://sashiko.dev/#/message/20260806100605.2C2C01F000E9%40smtp.kernel.org

v1 --> v2:
1. Rework failed-node tracking in patch 1: do not track zero-sized nodes,
   and keep a reserved_mem slot when tracking overflows.
2. Reject static reserved regions overlapping existing no-map regions.
3. Keep MEMBLOCK_NOMAP flag for static no-map regions when init failure.

Wandun Chen (5):
  of: reserved_mem: skip init for regions whose early reservation failed
  of: reserved_mem: reject static regions overlapping no-map memory
  of: reserved_mem: reject statically placed regions overlapping
    existing reservations
  of: reserved_mem: release dynamically allocated no-map region on init
    failure
  of: reserved_mem: retain static no-map memory on init failure

 drivers/of/of_reserved_mem.c | 87 +++++++++++++++++++++++++++++-------
 include/linux/memblock.h     |  1 +
 mm/memblock.c                | 14 ++++++
 3 files changed, 85 insertions(+), 17 deletions(-)

-- 
2.43.0