Naresh reported an issue with the non-atomic memory allocation of
cgroup local storage buffers:
[ 73.047526] BUG: sleeping function called from invalid context at
/srv/oe/build/tmp-rpb-glibc/work-shared/intel-corei7-64/kernel-source/mm/slab.h:421
[ 73.060915] in_atomic(): 1, irqs_disabled(): 0, pid: 3157, name: test_cgroup_sto
[ 73.068342] INFO: lockdep is turned off.
[ 73.072293] CPU: 2 PID: 3157 Comm: test_cgroup_sto Not tainted
4.20.0-rc2-next-
20181113 #1
[ 73.080548] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS
2.0b 07/27/2017
[ 73.088018] Call Trace:
[ 73.090463] dump_stack+0x70/0xa5
[ 73.093783] ___might_sleep+0x152/0x240
[ 73.097619] __might_sleep+0x4a/0x80
[ 73.101191] __kmalloc_node+0x1cf/0x2f0
[ 73.105031] ? cgroup_storage_update_elem+0x46/0x90
[ 73.109909] cgroup_storage_update_elem+0x46/0x90
cgroup_storage_update_elem() (as well as other update map update
callbacks) is called with disabled preemption, so GFP_ATOMIC
allocation should be used: e.g. alloc_htab_elem() in hashtab.c.
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>