cacheinfo: Fix shared_cpu_map to handle shared caches at different levels
authorYong-Xuan Wang <yongxuan.wang@sifive.com>
Tue, 17 Jan 2023 10:51:33 +0000 (10:51 +0000)
committerSudeep Holla <sudeep.holla@arm.com>
Wed, 18 Jan 2023 09:58:40 +0000 (09:58 +0000)
commit198102c9103fc78d8478495971947af77edb05c1
treedc235c9f049b878a843da2bbefa92e1a54fb4e6e
parent5944ce092b97caed5d86d961e963b883b5c44ee2
cacheinfo: Fix shared_cpu_map to handle shared caches at different levels

The cacheinfo sets up the shared_cpu_map by checking whether the caches
with the same index are shared between CPUs. However, this will trigger
slab-out-of-bounds access if the CPUs do not have the same cache hierarchy.
Another problem is the mismatched shared_cpu_map when the shared cache does
not have the same index between CPUs.

CPU0 I D L3
index 0 1 2 x
^ ^ ^ ^
index 0 1 2 3
CPU1 I D L2 L3

This patch checks each cache is shared with all caches on other CPUs.

Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
Link: https://lore.kernel.org/r/20230117105133.4445-2-yongxuan.wang@sifive.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
drivers/base/cacheinfo.c