From e5d0ce4e4a909a6a7a2cc6cab85f25df4241e9d4 Mon Sep 17 00:00:00 2001 From: Shakeel Butt Date: Wed, 12 May 2021 13:19:46 -0700 Subject: [PATCH] cgroup: disable controllers at parse time MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit stable inclusion from stable-v5.10.44 commit 5ca472d40e2daebbfd926701902debcab0bbd15c bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=405 CVE: NA ------------------------------------------------- [ Upstream commit 45e1ba40837ac2f6f4d4716bddb8d44bd7e4a251 ] This patch effectively reverts the commit a3e72739b7a7 ("cgroup: fix too early usage of static_branch_disable()"). The commit 6041186a3258 ("init: initialize jump labels before command line option parsing") has moved the jump_label_init() before parse_args() which has made the commit a3e72739b7a7 unnecessary. On the other hand there are consequences of disabling the controllers later as there are subsystems doing the controller checks for different decisions. One such incident is reported [1] regarding the memory controller and its impact on memory reclaim code. [1] https://lore.kernel.org/linux-mm/921e53f3-4b13-aab8-4a9e-e83ff15371e4@nec.com Signed-off-by: Shakeel Butt Reported-by: NOMURA JUNICHI(野村　淳一) Signed-off-by: Tejun Heo Tested-by: Jun'ichi Nomura Signed-off-by: Sasha Levin Signed-off-by: 13673108243 <13673108243@163.com> Reviewed-by: Jian Cheng Signed-off-by: Wang ShaoBo --- kernel/cgroup/cgroup.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 8c9f16778896..9f8abd440dec 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5683,8 +5683,8 @@ int __init cgroup_init_early(void) return 0; } -static u16 cgroup_disable_mask __initdata; #ifdef CONFIG_OPENEULER_RASPBERRYPI +static u16 cgroup_disable_mask __initdata; static u16 cgroup_enable_mask __initdata; static int __init cgroup_disable(char *str); #endif @@ -5755,12 +5755,8 @@ int __init cgroup_init(void) * disabled flag and cftype registration needs kmalloc, * both of which aren't available during early_init. */ - if (cgroup_disable_mask & (1 << ssid)) { - static_branch_disable(cgroup_subsys_enabled_key[ssid]); - printk(KERN_INFO "Disabling %s control group subsystem\n", - ss->name); + if (!cgroup_ssid_enabled(ssid)) continue; - } if (cgroup1_ssid_disabled(ssid)) printk(KERN_INFO "Disabling %s control group subsystem in v1 mounts\n", @@ -6275,7 +6271,10 @@ static int __init cgroup_disable(char *str) if (strcmp(token, ss->name) && strcmp(token, ss->legacy_name)) continue; - cgroup_disable_mask |= 1 << i; + + static_branch_disable(cgroup_subsys_enabled_key[i]); + pr_info("Disabling %s control group subsystem\n", + ss->name); } } return 1; -- GitLab