memblock: report failures when memblock_can_resize is not set
authorSong Shuai <songshuaishuai@tinylab.org>
Sat, 24 Jun 2023 03:26:07 +0000 (11:26 +0800)
committerMike Rapoport (IBM) <rppt@kernel.org>
Thu, 28 Sep 2023 06:04:33 +0000 (09:04 +0300)
commite96c6b8f212a510c9b22362de519f6e1d7920de5
treed6cbd48a68c88d396566a23681a0a370fc5af5d2
parent6465e260f48790807eef06b583b38ca9789b6072
memblock: report failures when memblock_can_resize is not set

The callers of memblock_reserve() do not check the return value
presuming that memblock_reserve() always succeeds, but there are
cases where it may fail.

Having numerous memblock reservations at early boot where
memblock_can_resize is unset may exhaust the INIT_MEMBLOCK_REGIONS sized
memblock.reserved regions array and an attempt to double this array via
memblock_double_array() will fail and will return -1 to the caller.

When this happens the system crashes anyway, but it's hard to identify
the reason for the crash.

Add a panic message to memblock_double_array() to aid debugging of the
cases when too many regions are reserved before memblock can resize
memblock.reserved array.

Link: https://lore.kernel.org/linux-kernel/20230614131746.3670303-1-songshuaishuai@tinylab.org/
Signed-off-by: Song Shuai <songshuaishuai@tinylab.org>
Link: https://lore.kernel.org/r/20230624032607.921173-1-songshuaishuai@tinylab.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
mm/memblock.c