Pengpeng Hou 95c7980851 lib: utils/mailbox: reject undersized RPMI shmem queues ...

The RPMI shared-memory mailbox transport derives qctx->num_slots from the
device-tree queue window size and the riscv,slot-size property. The current
initialization only checks that the queue window is nonzero before
subtracting the two RPMI header slots.

Reject queue windows that cannot provide the two header slots plus at least
two data ring slots. A zero data-slot count would later be used as a modulo
divisor, and a one-slot ring is also unusable with the current full/empty
convention because one empty slot is reserved to distinguish the two
states.

Also reject data-slot counts that cannot be represented by qctx->num_slots.

Fixes: 91f46fb47e ("lib/utils: Add RPMI messaging protocol and shared memory transport support")
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260828142521.14267-1-pengpeng@iscas.ac.cn
Signed-off-by: Anup Patel <anup@brainfault.org>

2026-10-23 13:06:37 +05:30

..

sbi

lib: sbi: use unsigned masks for HPM counter 31

2026-10-23 12:59:53 +05:30

utils

lib: utils/mailbox: reject undersized RPMI shmem queues

2026-10-23 13:06:37 +05:30