Re: mmotm 2022-03-16-17-42 uploaded (uml sub-x86_64, sched/fair, RCU)

[Randy Dunlap <rdunlap@infradead.org>]

On 3/16/22 21:30, Andrew Morton wrote:
> On Wed, 16 Mar 2022 21:21:16 -0700 Randy Dunlap <rdunlap@infradead.org> wrote:
> 
>>
>>
>> On 3/16/22 17:43, Andrew Morton wrote:
>>> The mm-of-the-moment snapshot 2022-03-16-17-42 has been uploaded to
>>>
>>>    https://www.ozlabs.org/~akpm/mmotm/
>>>
>>> mmotm-readme.txt says
>>>
>>> README for mm-of-the-moment:
>>>
>>> https://www.ozlabs.org/~akpm/mmotm/
>>>
>>> This is a snapshot of my -mm patch queue.  Uploaded at random hopefully
>>> more than once a week.
>>>
>>> You will need quilt to apply these patches to the latest Linus release (5.x
>>> or 5.x-rcY).  The series file is in broken-out.tar.gz and is duplicated in
>>> https://ozlabs.org/~akpm/mmotm/series
>>
>>
>> UML for x86_64, defconfig:
>>
>> In file included from ./arch/x86/include/generated/asm/rwonce.h:1:0,
>>                  from ../include/linux/compiler.h:248,
>>                  from ../include/linux/kernel.h:20,
>>                  from ../include/linux/cpumask.h:10,
>>                  from ../include/linux/energy_model.h:4,
>>                  from ../kernel/sched/fair.c:23:
>> ../include/linux/psi.h: In function ‘cgroup_move_task’:
>> ../include/linux/rcupdate.h:414:36: error: dereferencing pointer to incomplete type ‘struct css_set’
>>  #define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
>>                                     ^~~~
> 
> Works For Me.  I tried `make x86_64_defconfig' and `make i386_defconfig' too.
> 
> Can you please share that .config, or debug a bit?

$ make ARCH=um SUBARCH=x86_64 defconfig



This fixes the build error for me when CONFIG_PSI=n.

---
 include/linux/psi.h |    3 +++
 1 file changed, 3 insertions(+)

--- mmotm-2022-0316-1742.orig/include/linux/psi.h
+++ mmotm-2022-0316-1742/include/linux/psi.h
@@ -53,6 +53,9 @@ static inline int psi_cgroup_alloc(struc
 static inline void psi_cgroup_free(struct cgroup *cgrp)
 {
 }
+
+#include <linux/cgroup-defs.h>
+
 static inline void cgroup_move_task(struct task_struct *p, struct css_set *to)
 {
 	rcu_assign_pointer(p->cgroups, to);

-- 
~Randy