* [PATCH -next v3 1/3] blk-cgroup: dropping parent refcount after pd_free_fn() is done
2023-01-19 11:03 [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Yu Kuai
@ 2023-01-19 11:03 ` Yu Kuai
2023-01-19 16:41 ` Christoph Hellwig
2023-01-19 11:03 ` [PATCH -next v3 2/3] blk-cgroup: support to track if policy is online Yu Kuai
` (3 subsequent siblings)
4 siblings, 1 reply; 12+ messages in thread
From: Yu Kuai @ 2023-01-19 11:03 UTC (permalink / raw)
To: tj, hch, josef, axboe
Cc: cgroups, linux-block, linux-kernel, yukuai3, yukuai1, yi.zhang,
yangerkun
From: Yu Kuai <yukuai3@huawei.com>
Some cgroup policies will access parent pd through child pd even
after pd_offline_fn() is done. If pd_free_fn() for parent is called
before child, then UAF can be triggered. Hence it's better to guarantee
the order of pd_free_fn().
Currently refcount of parent blkg is dropped in __blkg_release(), which
is before pd_free_fn() is called in blkg_free_work_fn() while
blkg_free_work_fn() is called asynchronously.
This patch make sure pd_free_fn() called from removing cgroup is ordered
by delaying dropping parent refcount after calling pd_free_fn() for
child.
BTW, pd_free_fn() will also be called from blkcg_deactivate_policy()
from deleting device, and following patches will guarantee the order.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
---
block/blk-cgroup.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 4c94a6560f62..c6d7d1fce65a 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -124,6 +124,8 @@ static void blkg_free_workfn(struct work_struct *work)
if (blkg->pd[i])
blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
+ if (blkg->parent)
+ blkg_put(blkg->parent);
if (blkg->q)
blk_put_queue(blkg->q);
free_percpu(blkg->iostat_cpu);
@@ -158,8 +160,6 @@ static void __blkg_release(struct rcu_head *rcu)
/* release the blkcg and parent blkg refs this blkg has been holding */
css_put(&blkg->blkcg->css);
- if (blkg->parent)
- blkg_put(blkg->parent);
blkg_free(blkg);
}
--
2.31.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH -next v3 1/3] blk-cgroup: dropping parent refcount after pd_free_fn() is done
2023-01-19 11:03 ` [PATCH -next v3 1/3] blk-cgroup: dropping parent refcount after pd_free_fn() is done Yu Kuai
@ 2023-01-19 16:41 ` Christoph Hellwig
0 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2023-01-19 16:41 UTC (permalink / raw)
To: Yu Kuai
Cc: tj, hch, josef, axboe, cgroups, linux-block, linux-kernel,
yukuai3, yi.zhang, yangerkun
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH -next v3 2/3] blk-cgroup: support to track if policy is online
2023-01-19 11:03 [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Yu Kuai
2023-01-19 11:03 ` [PATCH -next v3 1/3] blk-cgroup: dropping parent refcount after pd_free_fn() is done Yu Kuai
@ 2023-01-19 11:03 ` Yu Kuai
2023-01-19 16:42 ` Christoph Hellwig
2023-01-19 11:03 ` [PATCH -next v3 3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy() Yu Kuai
` (2 subsequent siblings)
4 siblings, 1 reply; 12+ messages in thread
From: Yu Kuai @ 2023-01-19 11:03 UTC (permalink / raw)
To: tj, hch, josef, axboe
Cc: cgroups, linux-block, linux-kernel, yukuai3, yukuai1, yi.zhang,
yangerkun
From: Yu Kuai <yukuai3@huawei.com>
A new field 'online' is added to blkg_policy_data to fix following
2 problem:
1) In blkcg_activate_policy(), if pd_alloc_fn() with 'GFP_NOWAIT'
failed, 'queue_lock' will be dropped and pd_alloc_fn() will try again
without 'GFP_NOWAIT'. In the meantime, remove cgroup can race with
it, and pd_offline_fn() will be called without pd_init_fn() and
pd_online_fn(). This way null-ptr-deference can be triggered.
2) In order to synchronize pd_free_fn() from blkg_free_workfn() and
blkcg_deactivate_policy(), 'list_del_init(&blkg->q_node)' will be
delayed to blkg_free_workfn(), hence pd_offline_fn() can be called
first in blkg_destroy(), and then blkcg_deactivate_policy() will
call it again, we must prevent it.
The new field 'online' will be set after pd_online_fn() and will be
cleared after pd_offline_fn(), in the meantime pd_offline_fn() will only
be called if 'online' is set.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
---
block/blk-cgroup.c | 24 +++++++++++++++++-------
block/blk-cgroup.h | 1 +
2 files changed, 18 insertions(+), 7 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index c6d7d1fce65a..75f3c4460715 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -288,6 +288,7 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct gendisk *disk,
blkg->pd[i] = pd;
pd->blkg = blkg;
pd->plid = i;
+ pd->online = false;
}
return blkg;
@@ -359,8 +360,11 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, struct gendisk *disk,
for (i = 0; i < BLKCG_MAX_POLS; i++) {
struct blkcg_policy *pol = blkcg_policy[i];
- if (blkg->pd[i] && pol->pd_online_fn)
- pol->pd_online_fn(blkg->pd[i]);
+ if (blkg->pd[i]) {
+ if (pol->pd_online_fn)
+ pol->pd_online_fn(blkg->pd[i]);
+ blkg->pd[i]->online = true;
+ }
}
}
blkg->online = true;
@@ -465,8 +469,11 @@ static void blkg_destroy(struct blkcg_gq *blkg)
for (i = 0; i < BLKCG_MAX_POLS; i++) {
struct blkcg_policy *pol = blkcg_policy[i];
- if (blkg->pd[i] && pol->pd_offline_fn)
- pol->pd_offline_fn(blkg->pd[i]);
+ if (blkg->pd[i] && blkg->pd[i]->online) {
+ if (pol->pd_offline_fn)
+ pol->pd_offline_fn(blkg->pd[i]);
+ blkg->pd[i]->online = false;
+ }
}
blkg->online = false;
@@ -1448,6 +1455,7 @@ int blkcg_activate_policy(struct request_queue *q,
blkg->pd[pol->plid] = pd;
pd->blkg = blkg;
pd->plid = pol->plid;
+ pd->online = false;
}
/* all allocated, init in the same order */
@@ -1455,9 +1463,11 @@ int blkcg_activate_policy(struct request_queue *q,
list_for_each_entry_reverse(blkg, &q->blkg_list, q_node)
pol->pd_init_fn(blkg->pd[pol->plid]);
- if (pol->pd_online_fn)
- list_for_each_entry_reverse(blkg, &q->blkg_list, q_node)
+ list_for_each_entry_reverse(blkg, &q->blkg_list, q_node) {
+ if (pol->pd_online_fn)
pol->pd_online_fn(blkg->pd[pol->plid]);
+ blkg->pd[pol->plid]->online = true;
+ }
__set_bit(pol->plid, q->blkcg_pols);
ret = 0;
@@ -1519,7 +1529,7 @@ void blkcg_deactivate_policy(struct request_queue *q,
spin_lock(&blkcg->lock);
if (blkg->pd[pol->plid]) {
- if (pol->pd_offline_fn)
+ if (blkg->pd[pol->plid]->online && pol->pd_offline_fn)
pol->pd_offline_fn(blkg->pd[pol->plid]);
pol->pd_free_fn(blkg->pd[pol->plid]);
blkg->pd[pol->plid] = NULL;
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 1e94e404eaa8..b13ee84f358e 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -135,6 +135,7 @@ struct blkg_policy_data {
/* the blkg and policy id this per-policy data belongs to */
struct blkcg_gq *blkg;
int plid;
+ bool online;
};
/*
--
2.31.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH -next v3 2/3] blk-cgroup: support to track if policy is online
2023-01-19 11:03 ` [PATCH -next v3 2/3] blk-cgroup: support to track if policy is online Yu Kuai
@ 2023-01-19 16:42 ` Christoph Hellwig
0 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2023-01-19 16:42 UTC (permalink / raw)
To: Yu Kuai
Cc: tj, hch, josef, axboe, cgroups, linux-block, linux-kernel,
yukuai3, yi.zhang, yangerkun
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH -next v3 3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy()
2023-01-19 11:03 [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Yu Kuai
2023-01-19 11:03 ` [PATCH -next v3 1/3] blk-cgroup: dropping parent refcount after pd_free_fn() is done Yu Kuai
2023-01-19 11:03 ` [PATCH -next v3 2/3] blk-cgroup: support to track if policy is online Yu Kuai
@ 2023-01-19 11:03 ` Yu Kuai
2023-01-19 16:15 ` Tejun Heo
2023-01-19 16:43 ` Christoph Hellwig
2023-01-19 18:54 ` [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Jens Axboe
2023-01-29 22:20 ` Jens Axboe
4 siblings, 2 replies; 12+ messages in thread
From: Yu Kuai @ 2023-01-19 11:03 UTC (permalink / raw)
To: tj, hch, josef, axboe
Cc: cgroups, linux-block, linux-kernel, yukuai3, yukuai1, yi.zhang,
yangerkun
From: Yu Kuai <yukuai3@huawei.com>
Currently parent pd can be freed before child pd:
t1: remove cgroup C1
blkcg_destroy_blkgs
blkg_destroy
list_del_init(&blkg->q_node)
// remove blkg from queue list
percpu_ref_kill(&blkg->refcnt)
blkg_release
call_rcu
t2: from t1
__blkg_release
blkg_free
schedule_work
t4: deactivate policy
blkcg_deactivate_policy
pd_free_fn
// parent of C1 is freed first
t3: from t2
blkg_free_workfn
pd_free_fn
If policy(for example, ioc_timer_fn() from iocost) access parent pd from
child pd after pd_offline_fn(), then UAF can be triggered.
Fix the problem by delaying 'list_del_init(&blkg->q_node)' from
blkg_destroy() to blkg_free_workfn(), and using a new disk level mutex to
synchronize blkg_free_workfn() and blkcg_deactivate_policy().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
---
block/blk-cgroup.c | 35 +++++++++++++++++++++++++++++------
include/linux/blkdev.h | 1 +
2 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 75f3c4460715..cb110fc51940 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -118,16 +118,32 @@ static void blkg_free_workfn(struct work_struct *work)
{
struct blkcg_gq *blkg = container_of(work, struct blkcg_gq,
free_work);
+ struct request_queue *q = blkg->q;
int i;
+ /*
+ * pd_free_fn() can also be called from blkcg_deactivate_policy(),
+ * in order to make sure pd_free_fn() is called in order, the deletion
+ * of the list blkg->q_node is delayed to here from blkg_destroy(), and
+ * blkcg_mutex is used to synchronize blkg_free_workfn() and
+ * blkcg_deactivate_policy().
+ */
+ if (q)
+ mutex_lock(&q->blkcg_mutex);
+
for (i = 0; i < BLKCG_MAX_POLS; i++)
if (blkg->pd[i])
blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
if (blkg->parent)
blkg_put(blkg->parent);
- if (blkg->q)
- blk_put_queue(blkg->q);
+
+ if (q) {
+ list_del_init(&blkg->q_node);
+ mutex_unlock(&q->blkcg_mutex);
+ blk_put_queue(q);
+ }
+
free_percpu(blkg->iostat_cpu);
percpu_ref_exit(&blkg->refcnt);
kfree(blkg);
@@ -462,9 +478,14 @@ static void blkg_destroy(struct blkcg_gq *blkg)
lockdep_assert_held(&blkg->q->queue_lock);
lockdep_assert_held(&blkcg->lock);
- /* Something wrong if we are trying to remove same group twice */
- WARN_ON_ONCE(list_empty(&blkg->q_node));
- WARN_ON_ONCE(hlist_unhashed(&blkg->blkcg_node));
+ /*
+ * blkg stays on the queue list until blkg_free_workfn(), see details in
+ * blkg_free_workfn(), hence this function can be called from
+ * blkcg_destroy_blkgs() first and again from blkg_destroy_all() before
+ * blkg_free_workfn().
+ */
+ if (hlist_unhashed(&blkg->blkcg_node))
+ return;
for (i = 0; i < BLKCG_MAX_POLS; i++) {
struct blkcg_policy *pol = blkcg_policy[i];
@@ -479,7 +500,6 @@ static void blkg_destroy(struct blkcg_gq *blkg)
blkg->online = false;
radix_tree_delete(&blkcg->blkg_tree, blkg->q->id);
- list_del_init(&blkg->q_node);
hlist_del_init_rcu(&blkg->blkcg_node);
/*
@@ -1280,6 +1300,7 @@ int blkcg_init_disk(struct gendisk *disk)
int ret;
INIT_LIST_HEAD(&q->blkg_list);
+ mutex_init(&q->blkcg_mutex);
new_blkg = blkg_alloc(&blkcg_root, disk, GFP_KERNEL);
if (!new_blkg)
@@ -1520,6 +1541,7 @@ void blkcg_deactivate_policy(struct request_queue *q,
if (queue_is_mq(q))
blk_mq_freeze_queue(q);
+ mutex_lock(&q->blkcg_mutex);
spin_lock_irq(&q->queue_lock);
__clear_bit(pol->plid, q->blkcg_pols);
@@ -1538,6 +1560,7 @@ void blkcg_deactivate_policy(struct request_queue *q,
}
spin_unlock_irq(&q->queue_lock);
+ mutex_unlock(&q->blkcg_mutex);
if (queue_is_mq(q))
blk_mq_unfreeze_queue(q);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index b87ed829ab94..53ae0a7fe377 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -485,6 +485,7 @@ struct request_queue {
DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
struct blkcg_gq *root_blkg;
struct list_head blkg_list;
+ struct mutex blkcg_mutex;
#endif
struct queue_limits limits;
--
2.31.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH -next v3 3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy()
2023-01-19 11:03 ` [PATCH -next v3 3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy() Yu Kuai
@ 2023-01-19 16:15 ` Tejun Heo
2023-01-19 16:43 ` Christoph Hellwig
1 sibling, 0 replies; 12+ messages in thread
From: Tejun Heo @ 2023-01-19 16:15 UTC (permalink / raw)
To: Yu Kuai
Cc: hch, josef, axboe, cgroups, linux-block, linux-kernel, yukuai3,
yi.zhang, yangerkun
On Thu, Jan 19, 2023 at 07:03:50PM +0800, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@huawei.com>
>
> Currently parent pd can be freed before child pd:
>
> t1: remove cgroup C1
> blkcg_destroy_blkgs
> blkg_destroy
> list_del_init(&blkg->q_node)
> // remove blkg from queue list
> percpu_ref_kill(&blkg->refcnt)
> blkg_release
> call_rcu
>
> t2: from t1
> __blkg_release
> blkg_free
> schedule_work
> t4: deactivate policy
> blkcg_deactivate_policy
> pd_free_fn
> // parent of C1 is freed first
> t3: from t2
> blkg_free_workfn
> pd_free_fn
>
> If policy(for example, ioc_timer_fn() from iocost) access parent pd from
> child pd after pd_offline_fn(), then UAF can be triggered.
>
> Fix the problem by delaying 'list_del_init(&blkg->q_node)' from
> blkg_destroy() to blkg_free_workfn(), and using a new disk level mutex to
> synchronize blkg_free_workfn() and blkcg_deactivate_policy().
>
> Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Thanks.
--
tejun
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH -next v3 3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy()
2023-01-19 11:03 ` [PATCH -next v3 3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy() Yu Kuai
2023-01-19 16:15 ` Tejun Heo
@ 2023-01-19 16:43 ` Christoph Hellwig
1 sibling, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2023-01-19 16:43 UTC (permalink / raw)
To: Yu Kuai
Cc: tj, hch, josef, axboe, cgroups, linux-block, linux-kernel,
yukuai3, yi.zhang, yangerkun
The this change itself looks good, but it will clash badly with my
"switch blk-cgroup to work on gendisk" series:
Reviewed-by: Christoph Hellwig <hch@lst.de>
Can I get some reviews for that series once I rebase and repost it
after this series is merged?
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order
2023-01-19 11:03 [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Yu Kuai
` (2 preceding siblings ...)
2023-01-19 11:03 ` [PATCH -next v3 3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy() Yu Kuai
@ 2023-01-19 18:54 ` Jens Axboe
2023-01-29 6:06 ` Yu Kuai
2023-01-29 22:20 ` Jens Axboe
4 siblings, 1 reply; 12+ messages in thread
From: Jens Axboe @ 2023-01-19 18:54 UTC (permalink / raw)
To: Yu Kuai, tj, hch, josef
Cc: cgroups, linux-block, linux-kernel, yukuai3, yi.zhang, yangerkun
On 1/19/23 4:03 AM, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@huawei.com>
>
> Changes in v3:
> - add ack tag from Tejun for patch 1,2
> - as suggested by Tejun, update commit message and comments in patch 3
>
> The problem was found in iocost orignally([1]) that ioc can be freed in
> ioc_pd_free(). And later we found that there are more problem in
> iocost([2]).
>
> After some discussion, as suggested by Tejun([3]), we decide to fix the
> problem that parent pd can be freed before child pd in cgroup layer
> first. And the problem in [1] will be fixed later if this patchset is
> applied.
Doesn't apply against for-6.3/block (or linux-next or my for-next, for
that matter). Can you resend a tested one against for-6.3/block?
--
Jens Axboe
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order
2023-01-19 18:54 ` [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Jens Axboe
@ 2023-01-29 6:06 ` Yu Kuai
2023-01-29 21:48 ` Jens Axboe
0 siblings, 1 reply; 12+ messages in thread
From: Yu Kuai @ 2023-01-29 6:06 UTC (permalink / raw)
To: Jens Axboe, Yu Kuai, tj, hch, josef
Cc: cgroups, linux-block, linux-kernel, yi.zhang, yangerkun, yukuai (C)
Hi, Jens
在 2023/01/20 2:54, Jens Axboe 写道:
> On 1/19/23 4:03 AM, Yu Kuai wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> Changes in v3:
>> - add ack tag from Tejun for patch 1,2
>> - as suggested by Tejun, update commit message and comments in patch 3
>>
>> The problem was found in iocost orignally([1]) that ioc can be freed in
>> ioc_pd_free(). And later we found that there are more problem in
>> iocost([2]).
>>
>> After some discussion, as suggested by Tejun([3]), we decide to fix the
>> problem that parent pd can be freed before child pd in cgroup layer
>> first. And the problem in [1] will be fixed later if this patchset is
>> applied.
>
> Doesn't apply against for-6.3/block (or linux-next or my for-next, for
> that matter). Can you resend a tested one against for-6.3/block?
>
This is weird, I just test latest linux-next, and I can apply this
patchset on the top of following commit:
For latest for-6.3/block, this patch 2 can't be applied because
following commit is not here:
e3ff8887e7db blk-cgroup: fix missing pd_online_fn() while activating policy
But this patch is already merged into 6.2-rc5.
Thanks,
Kuai
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order
2023-01-29 6:06 ` Yu Kuai
@ 2023-01-29 21:48 ` Jens Axboe
0 siblings, 0 replies; 12+ messages in thread
From: Jens Axboe @ 2023-01-29 21:48 UTC (permalink / raw)
To: Yu Kuai, tj, hch, josef
Cc: cgroups, linux-block, linux-kernel, yi.zhang, yangerkun, yukuai (C)
On 1/28/23 11:06 PM, Yu Kuai wrote:
> Hi, Jens
>
> 在 2023/01/20 2:54, Jens Axboe 写道:
>> On 1/19/23 4:03 AM, Yu Kuai wrote:
>>> From: Yu Kuai <yukuai3@huawei.com>
>>>
>>> Changes in v3:
>>> - add ack tag from Tejun for patch 1,2
>>> - as suggested by Tejun, update commit message and comments in patch 3
>>>
>>> The problem was found in iocost orignally([1]) that ioc can be freed in
>>> ioc_pd_free(). And later we found that there are more problem in
>>> iocost([2]).
>>>
>>> After some discussion, as suggested by Tejun([3]), we decide to fix the
>>> problem that parent pd can be freed before child pd in cgroup layer
>>> first. And the problem in [1] will be fixed later if this patchset is
>>> applied.
>>
>> Doesn't apply against for-6.3/block (or linux-next or my for-next, for
>> that matter). Can you resend a tested one against for-6.3/block?
>>
>
> This is weird, I just test latest linux-next, and I can apply this
> patchset on the top of following commit:
>
> For latest for-6.3/block, this patch 2 can't be applied because
> following commit is not here:
>
> e3ff8887e7db blk-cgroup: fix missing pd_online_fn() while activating policy
>
> But this patch is already merged into 6.2-rc5.
Since I have one more conflict, I think we'll just rebase for-6.3/block
when -rc6 is out, and then it should apply cleanly.
--
Jens Axboe
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order
2023-01-19 11:03 [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Yu Kuai
` (3 preceding siblings ...)
2023-01-19 18:54 ` [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called in order Jens Axboe
@ 2023-01-29 22:20 ` Jens Axboe
4 siblings, 0 replies; 12+ messages in thread
From: Jens Axboe @ 2023-01-29 22:20 UTC (permalink / raw)
To: tj, hch, josef, Yu Kuai
Cc: cgroups, linux-block, linux-kernel, yukuai3, yi.zhang, yangerkun
On Thu, 19 Jan 2023 19:03:47 +0800, Yu Kuai wrote:
> Changes in v3:
> - add ack tag from Tejun for patch 1,2
> - as suggested by Tejun, update commit message and comments in patch 3
>
> The problem was found in iocost orignally([1]) that ioc can be freed in
> ioc_pd_free(). And later we found that there are more problem in
> iocost([2]).
>
> [...]
Applied, thanks!
[1/3] blk-cgroup: dropping parent refcount after pd_free_fn() is done
commit: c7241babf0855d8a6180cd1743ff0ec34de40b4e
[2/3] blk-cgroup: support to track if policy is online
commit: dfd6200a095440b663099d8d42f1efb0175a1ce3
[3/3] blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy()
commit: f1c006f1c6850c14040f8337753a63119bba39b9
Best regards,
--
Jens Axboe
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