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| author | Chen Ridong <chenridong@huawei.com> | 2024-08-05 03:30:15 +0200 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2024-08-05 22:52:40 +0200 |
| commit | 959ab6350add903e352890af53e86663739fcb9a (patch) | |
| tree | 377677874dd1c8ae0797c0c1282f11d7fbeec904 /kernel | |
| parent | Linux 6.11-rc1 (diff) | |
| download | linux-959ab6350add903e352890af53e86663739fcb9a.tar.xz linux-959ab6350add903e352890af53e86663739fcb9a.zip | |
cgroup/cpuset: fix panic caused by partcmd_update
We find a bug as below:
BUG: unable to handle page fault for address: 00000003
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 358 Comm: bash Tainted: G W I 6.6.0-10893-g60d6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/4
RIP: 0010:partition_sched_domains_locked+0x483/0x600
Code: 01 48 85 d2 74 0d 48 83 05 29 3f f8 03 01 f3 48 0f bc c2 89 c0 48 9
RSP: 0018:ffffc90000fdbc58 EFLAGS: 00000202
RAX: 0000000100000003 RBX: ffff888100b3dfa0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000002fe80
RBP: ffff888100b3dfb0 R08: 0000000000000001 R09: 0000000000000000
R10: ffffc90000fdbcb0 R11: 0000000000000004 R12: 0000000000000002
R13: ffff888100a92b48 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f44a5425740(0000) GS:ffff888237d80000(0000) knlGS:0000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100030973 CR3: 000000010722c000 CR4: 00000000000006e0
Call Trace:
<TASK>
? show_regs+0x8c/0xa0
? __die_body+0x23/0xa0
? __die+0x3a/0x50
? page_fault_oops+0x1d2/0x5c0
? partition_sched_domains_locked+0x483/0x600
? search_module_extables+0x2a/0xb0
? search_exception_tables+0x67/0x90
? kernelmode_fixup_or_oops+0x144/0x1b0
? __bad_area_nosemaphore+0x211/0x360
? up_read+0x3b/0x50
? bad_area_nosemaphore+0x1a/0x30
? exc_page_fault+0x890/0xd90
? __lock_acquire.constprop.0+0x24f/0x8d0
? __lock_acquire.constprop.0+0x24f/0x8d0
? asm_exc_page_fault+0x26/0x30
? partition_sched_domains_locked+0x483/0x600
? partition_sched_domains_locked+0xf0/0x600
rebuild_sched_domains_locked+0x806/0xdc0
update_partition_sd_lb+0x118/0x130
cpuset_write_resmask+0xffc/0x1420
cgroup_file_write+0xb2/0x290
kernfs_fop_write_iter+0x194/0x290
new_sync_write+0xeb/0x160
vfs_write+0x16f/0x1d0
ksys_write+0x81/0x180
__x64_sys_write+0x21/0x30
x64_sys_call+0x2f25/0x4630
do_syscall_64+0x44/0xb0
entry_SYSCALL_64_after_hwframe+0x78/0xe2
RIP: 0033:0x7f44a553c887
It can be reproduced with cammands:
cd /sys/fs/cgroup/
mkdir test
cd test/
echo +cpuset > ../cgroup.subtree_control
echo root > cpuset.cpus.partition
cat /sys/fs/cgroup/cpuset.cpus.effective
0-3
echo 0-3 > cpuset.cpus // taking away all cpus from root
This issue is caused by the incorrect rebuilding of scheduling domains.
In this scenario, test/cpuset.cpus.partition should be an invalid root
and should not trigger the rebuilding of scheduling domains. When calling
update_parent_effective_cpumask with partcmd_update, if newmask is not
null, it should recheck newmask whether there are cpus is available
for parect/cs that has tasks.
Fixes: 0c7f293efc87 ("cgroup/cpuset: Add cpuset.cpus.exclusive.effective for v2")
Cc: stable@vger.kernel.org # v6.7+
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cgroup/cpuset.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 40ec4abaf440..a9b6d56eeffa 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1991,6 +1991,8 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, part_error = PERR_CPUSEMPTY; goto write_error; } + /* Check newmask again, whether cpus are available for parent/cs */ + nocpu |= tasks_nocpu_error(parent, cs, newmask); /* * partcmd_update with newmask: |