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| author | Yong-Xuan Wang <yongxuan.wang@sifive.com> | 2023-01-17 10:51:33 +0000 |
|---|---|---|
| committer | Sudeep Holla <sudeep.holla@arm.com> | 2023-01-18 09:58:40 +0000 |
| commit | 198102c9103fc78d8478495971947af77edb05c1 (patch) | |
| tree | dc235c9f049b878a843da2bbefa92e1a54fb4e6e /drivers/base/cacheinfo.c | |
| parent | 5944ce092b97caed5d86d961e963b883b5c44ee2 (diff) | |
| download | linux-198102c9103fc78d8478495971947af77edb05c1.tar.gz linux-198102c9103fc78d8478495971947af77edb05c1.tar.bz2 linux-198102c9103fc78d8478495971947af77edb05c1.zip | |
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>
Diffstat (limited to 'drivers/base/cacheinfo.c')
| -rw-r--r-- | drivers/base/cacheinfo.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index c9bcecf76c7f..418a18acc8f9 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -319,7 +319,7 @@ 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) @@ -347,11 +347,13 @@ 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 */ @@ -365,7 +367,7 @@ 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); @@ -376,9 +378,14 @@ 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; + } + } } } } |