summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorYong-Xuan Wang <yongxuan.wang@sifive.com>2023-01-17 13:51:33 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-03-11 15:50:39 +0300
commitdea49f2993f57d8a2df2cacb0bf649ef49b28879 (patch)
tree540ac437a92c0fc928fb91360a055a9917258e72
parentcc00340fb1226a2a3a5cf15473ac417da3c952f1 (diff)
downloadlinux-dea49f2993f57d8a2df2cacb0bf649ef49b28879.tar.xz
cacheinfo: Fix shared_cpu_map to handle shared caches at different levels
[ Upstream commit 198102c9103fc78d8478495971947af77edb05c1 ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r--drivers/base/cacheinfo.c27
1 files changed, 17 insertions, 10 deletions
diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
index 950b22cdb5f7..f05acf3c16c6 100644
--- a/drivers/base/cacheinfo.c
+++ b/drivers/base/cacheinfo.c
@@ -256,7 +256,7 @@ static int cache_shared_cpu_map_setup(unsigned int cpu)
{
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
struct cacheinfo *this_leaf, *sib_leaf;
- unsigned int index;
+ unsigned int index, sib_index;
int ret = 0;
if (this_cpu_ci->cpu_map_populated)
@@ -284,11 +284,13 @@ static int cache_shared_cpu_map_setup(unsigned int cpu)
if (i == cpu || !sib_cpu_ci->info_list)
continue;/* skip if itself or no cacheinfo */
-
- sib_leaf = per_cpu_cacheinfo_idx(i, index);
- if (cache_leaves_are_shared(this_leaf, sib_leaf)) {
- cpumask_set_cpu(cpu, &sib_leaf->shared_cpu_map);
- cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
+ for (sib_index = 0; sib_index < cache_leaves(i); sib_index++) {
+ sib_leaf = per_cpu_cacheinfo_idx(i, sib_index);
+ if (cache_leaves_are_shared(this_leaf, sib_leaf)) {
+ cpumask_set_cpu(cpu, &sib_leaf->shared_cpu_map);
+ cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
+ break;
+ }
}
}
/* record the maximum cache line size */
@@ -302,7 +304,7 @@ static int cache_shared_cpu_map_setup(unsigned int cpu)
static void cache_shared_cpu_map_remove(unsigned int cpu)
{
struct cacheinfo *this_leaf, *sib_leaf;
- unsigned int sibling, index;
+ unsigned int sibling, index, sib_index;
for (index = 0; index < cache_leaves(cpu); index++) {
this_leaf = per_cpu_cacheinfo_idx(cpu, index);
@@ -313,9 +315,14 @@ static void cache_shared_cpu_map_remove(unsigned int cpu)
if (sibling == cpu || !sib_cpu_ci->info_list)
continue;/* skip if itself or no cacheinfo */
- sib_leaf = per_cpu_cacheinfo_idx(sibling, index);
- cpumask_clear_cpu(cpu, &sib_leaf->shared_cpu_map);
- cpumask_clear_cpu(sibling, &this_leaf->shared_cpu_map);
+ for (sib_index = 0; sib_index < cache_leaves(sibling); sib_index++) {
+ sib_leaf = per_cpu_cacheinfo_idx(sibling, sib_index);
+ if (cache_leaves_are_shared(this_leaf, sib_leaf)) {
+ cpumask_clear_cpu(cpu, &sib_leaf->shared_cpu_map);
+ cpumask_clear_cpu(sibling, &this_leaf->shared_cpu_map);
+ break;
+ }
+ }
}
}
}