From: Wang Wensheng <wangwensheng4@huawei.com> hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5DS9S CVE: NA ------------------------------------------------- The user doesn't care about the start address of the dvpp range, what is mattered is that the virtual space tagged DVPP located at in a 16G range. So we can safely drop the dvpp address space as long as it's empty during merging process. Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- mm/share_pool.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/mm/share_pool.c b/mm/share_pool.c index 1c10b136f20f..b14152acbee8 100644 --- a/mm/share_pool.c +++ b/mm/share_pool.c @@ -246,16 +246,23 @@ static int sp_mapping_group_setup(struct mm_struct *mm, struct sp_group *spg) struct sp_group *local = master->local; if (!list_empty(&spg->procs) && !(spg->flag & SPG_FLAG_NON_DVPP)) { - if (!can_mappings_merge(local->dvpp, spg->dvpp)) { - pr_info_ratelimited("address space conflict, id=%d\n", spg->id); - return -EINVAL; - } + /* + * Don't return an error when the mappings' address range conflict. + * As long as the mapping is unused, we can drop the empty mapping. + * This may change the address range for the task or group implicitly, + * give a warn for it. + */ + bool is_conflict = !can_mappings_merge(local->dvpp, spg->dvpp); - if (is_mapping_empty(local->dvpp)) + if (is_mapping_empty(local->dvpp)) { sp_mapping_merge(spg->dvpp, local->dvpp); - else if (is_mapping_empty(spg->dvpp)) + if (is_conflict) + pr_warn_ratelimited("task address space conflict, spg_id=%d\n", spg->id); + } else if (is_mapping_empty(spg->dvpp)) { sp_mapping_merge(local->dvpp, spg->dvpp); - else { + if (is_conflict) + pr_warn_ratelimited("group address space conflict, spg_id=%d\n", spg->id); + } else { pr_info_ratelimited("Duplicate address space, id=%d\n", spg->id); return -EINVAL; } -- 2.20.1