* [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning
@ 2021-11-21 14:22 Guoqing Jiang
2021-11-22 7:25 ` Jinpu Wang
2021-11-22 7:44 ` Leon Romanovsky
0 siblings, 2 replies; 5+ messages in thread
From: Guoqing Jiang @ 2021-11-21 14:22 UTC (permalink / raw)
To: haris.iqbal, jinpu.wang, jgg; +Cc: linux-rdma, Guoqing Jiang
With preemption enabled (CONFIG_DEBUG_PREEMPT=y), the following appeared
when rnbd client tries to map remote block device.
[ 2123.221071] BUG: using smp_processor_id() in preemptible [00000000] code: bash/1733
[ 2123.221175] caller is debug_smp_processor_id+0x17/0x20
[ 2123.221214] CPU: 0 PID: 1733 Comm: bash Not tainted 5.16.0-rc1 #5
[ 2123.221218] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
[ 2123.221229] Call Trace:
[ 2123.221231] <TASK>
[ 2123.221235] dump_stack_lvl+0x5d/0x78
[ 2123.221252] dump_stack+0x10/0x12
[ 2123.221257] check_preemption_disabled+0xe4/0xf0
[ 2123.221266] debug_smp_processor_id+0x17/0x20
[ 2123.221271] rtrs_clt_update_all_stats+0x3b/0x70 [rtrs_client]
[ 2123.221285] rtrs_clt_read_req+0xc3/0x380 [rtrs_client]
[ 2123.221298] ? rtrs_clt_init_req+0xe3/0x120 [rtrs_client]
[ 2123.221321] rtrs_clt_request+0x1a7/0x320 [rtrs_client]
[ 2123.221340] ? 0xffffffffc0ab1000
[ 2123.221357] send_usr_msg+0xbf/0x160 [rnbd_client]
[ 2123.221370] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
[ 2123.221377] ? send_usr_msg+0x160/0x160 [rnbd_client]
[ 2123.221386] ? sg_alloc_table+0x27/0xb0
[ 2123.221395] ? sg_zero_buffer+0xd0/0xd0
[ 2123.221407] send_msg_sess_info+0xe9/0x180 [rnbd_client]
[ 2123.221413] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
[ 2123.221429] ? blk_mq_alloc_tag_set+0x2ef/0x370
[ 2123.221447] rnbd_clt_map_device+0xba8/0xcd0 [rnbd_client]
[ 2123.221462] ? send_msg_open+0x200/0x200 [rnbd_client]
[ 2123.221479] rnbd_clt_map_device_store+0x3e5/0x620 [rnbd_client
To supress the calltrace, let's call get_cpu_ptr/put_cpu_ptr pair in
rtrs_clt_update_rdma_stats to disable preemption when accessing per-cpu
variable.
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
---
drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
index f7e459fe68be..6ff72f2b1a3a 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
@@ -169,9 +169,10 @@ static inline void rtrs_clt_update_rdma_stats(struct rtrs_clt_stats *stats,
{
struct rtrs_clt_stats_pcpu *s;
- s = this_cpu_ptr(stats->pcpu_stats);
+ s = get_cpu_ptr(stats->pcpu_stats);
s->rdma.dir[d].cnt++;
s->rdma.dir[d].size_total += size;
+ put_cpu_ptr(stats->pcpu_stats);
}
void rtrs_clt_update_all_stats(struct rtrs_clt_io_req *req, int dir)
--
2.31.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning
2021-11-21 14:22 [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning Guoqing Jiang
@ 2021-11-22 7:25 ` Jinpu Wang
2021-11-22 7:44 ` Leon Romanovsky
1 sibling, 0 replies; 5+ messages in thread
From: Jinpu Wang @ 2021-11-22 7:25 UTC (permalink / raw)
To: Guoqing Jiang; +Cc: haris.iqbal, jgg, linux-rdma
On Sun, Nov 21, 2021 at 3:22 PM Guoqing Jiang <guoqing.jiang@linux.dev> wrote:
>
> With preemption enabled (CONFIG_DEBUG_PREEMPT=y), the following appeared
> when rnbd client tries to map remote block device.
>
> [ 2123.221071] BUG: using smp_processor_id() in preemptible [00000000] code: bash/1733
> [ 2123.221175] caller is debug_smp_processor_id+0x17/0x20
> [ 2123.221214] CPU: 0 PID: 1733 Comm: bash Not tainted 5.16.0-rc1 #5
> [ 2123.221218] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
> [ 2123.221229] Call Trace:
> [ 2123.221231] <TASK>
> [ 2123.221235] dump_stack_lvl+0x5d/0x78
> [ 2123.221252] dump_stack+0x10/0x12
> [ 2123.221257] check_preemption_disabled+0xe4/0xf0
> [ 2123.221266] debug_smp_processor_id+0x17/0x20
> [ 2123.221271] rtrs_clt_update_all_stats+0x3b/0x70 [rtrs_client]
> [ 2123.221285] rtrs_clt_read_req+0xc3/0x380 [rtrs_client]
> [ 2123.221298] ? rtrs_clt_init_req+0xe3/0x120 [rtrs_client]
> [ 2123.221321] rtrs_clt_request+0x1a7/0x320 [rtrs_client]
> [ 2123.221340] ? 0xffffffffc0ab1000
> [ 2123.221357] send_usr_msg+0xbf/0x160 [rnbd_client]
> [ 2123.221370] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
> [ 2123.221377] ? send_usr_msg+0x160/0x160 [rnbd_client]
> [ 2123.221386] ? sg_alloc_table+0x27/0xb0
> [ 2123.221395] ? sg_zero_buffer+0xd0/0xd0
> [ 2123.221407] send_msg_sess_info+0xe9/0x180 [rnbd_client]
> [ 2123.221413] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
> [ 2123.221429] ? blk_mq_alloc_tag_set+0x2ef/0x370
> [ 2123.221447] rnbd_clt_map_device+0xba8/0xcd0 [rnbd_client]
> [ 2123.221462] ? send_msg_open+0x200/0x200 [rnbd_client]
> [ 2123.221479] rnbd_clt_map_device_store+0x3e5/0x620 [rnbd_client
>
> To supress the calltrace, let's call get_cpu_ptr/put_cpu_ptr pair in
> rtrs_clt_update_rdma_stats to disable preemption when accessing per-cpu
> variable.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Looks good to me.
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Thanks Guoqing.
> ---
> drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> index f7e459fe68be..6ff72f2b1a3a 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> @@ -169,9 +169,10 @@ static inline void rtrs_clt_update_rdma_stats(struct rtrs_clt_stats *stats,
> {
> struct rtrs_clt_stats_pcpu *s;
>
> - s = this_cpu_ptr(stats->pcpu_stats);
> + s = get_cpu_ptr(stats->pcpu_stats);
> s->rdma.dir[d].cnt++;
> s->rdma.dir[d].size_total += size;
> + put_cpu_ptr(stats->pcpu_stats);
> }
>
> void rtrs_clt_update_all_stats(struct rtrs_clt_io_req *req, int dir)
> --
> 2.31.1
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning
2021-11-21 14:22 [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning Guoqing Jiang
2021-11-22 7:25 ` Jinpu Wang
@ 2021-11-22 7:44 ` Leon Romanovsky
2021-11-22 8:20 ` Jinpu Wang
1 sibling, 1 reply; 5+ messages in thread
From: Leon Romanovsky @ 2021-11-22 7:44 UTC (permalink / raw)
To: Guoqing Jiang; +Cc: haris.iqbal, jinpu.wang, jgg, linux-rdma
On Sun, Nov 21, 2021 at 10:22:23PM +0800, Guoqing Jiang wrote:
> With preemption enabled (CONFIG_DEBUG_PREEMPT=y), the following appeared
> when rnbd client tries to map remote block device.
>
> [ 2123.221071] BUG: using smp_processor_id() in preemptible [00000000] code: bash/1733
> [ 2123.221175] caller is debug_smp_processor_id+0x17/0x20
> [ 2123.221214] CPU: 0 PID: 1733 Comm: bash Not tainted 5.16.0-rc1 #5
> [ 2123.221218] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
> [ 2123.221229] Call Trace:
> [ 2123.221231] <TASK>
> [ 2123.221235] dump_stack_lvl+0x5d/0x78
> [ 2123.221252] dump_stack+0x10/0x12
> [ 2123.221257] check_preemption_disabled+0xe4/0xf0
> [ 2123.221266] debug_smp_processor_id+0x17/0x20
> [ 2123.221271] rtrs_clt_update_all_stats+0x3b/0x70 [rtrs_client]
> [ 2123.221285] rtrs_clt_read_req+0xc3/0x380 [rtrs_client]
> [ 2123.221298] ? rtrs_clt_init_req+0xe3/0x120 [rtrs_client]
> [ 2123.221321] rtrs_clt_request+0x1a7/0x320 [rtrs_client]
> [ 2123.221340] ? 0xffffffffc0ab1000
> [ 2123.221357] send_usr_msg+0xbf/0x160 [rnbd_client]
> [ 2123.221370] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
> [ 2123.221377] ? send_usr_msg+0x160/0x160 [rnbd_client]
> [ 2123.221386] ? sg_alloc_table+0x27/0xb0
> [ 2123.221395] ? sg_zero_buffer+0xd0/0xd0
> [ 2123.221407] send_msg_sess_info+0xe9/0x180 [rnbd_client]
> [ 2123.221413] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
> [ 2123.221429] ? blk_mq_alloc_tag_set+0x2ef/0x370
> [ 2123.221447] rnbd_clt_map_device+0xba8/0xcd0 [rnbd_client]
> [ 2123.221462] ? send_msg_open+0x200/0x200 [rnbd_client]
> [ 2123.221479] rnbd_clt_map_device_store+0x3e5/0x620 [rnbd_client
>
> To supress the calltrace, let's call get_cpu_ptr/put_cpu_ptr pair in
> rtrs_clt_update_rdma_stats to disable preemption when accessing per-cpu
> variable.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
> ---
> drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> index f7e459fe68be..6ff72f2b1a3a 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> @@ -169,9 +169,10 @@ static inline void rtrs_clt_update_rdma_stats(struct rtrs_clt_stats *stats,
> {
> struct rtrs_clt_stats_pcpu *s;
>
> - s = this_cpu_ptr(stats->pcpu_stats);
> + s = get_cpu_ptr(stats->pcpu_stats);
> s->rdma.dir[d].cnt++;
> s->rdma.dir[d].size_total += size;
> + put_cpu_ptr(stats->pcpu_stats);
I see that this_cpu_ptr() is used in many other places in rtrs-clt-stats.c,
why do we need to change only one place?
Thanks
> }
>
> void rtrs_clt_update_all_stats(struct rtrs_clt_io_req *req, int dir)
> --
> 2.31.1
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning
2021-11-22 7:44 ` Leon Romanovsky
@ 2021-11-22 8:20 ` Jinpu Wang
2021-11-22 8:23 ` Guoqing Jiang
0 siblings, 1 reply; 5+ messages in thread
From: Jinpu Wang @ 2021-11-22 8:20 UTC (permalink / raw)
To: Leon Romanovsky, Guoqing Jiang; +Cc: haris.iqbal, jgg, linux-rdma
On Mon, Nov 22, 2021 at 8:44 AM Leon Romanovsky <leon@kernel.org> wrote:
>
> On Sun, Nov 21, 2021 at 10:22:23PM +0800, Guoqing Jiang wrote:
> > With preemption enabled (CONFIG_DEBUG_PREEMPT=y), the following appeared
> > when rnbd client tries to map remote block device.
> >
> > [ 2123.221071] BUG: using smp_processor_id() in preemptible [00000000] code: bash/1733
> > [ 2123.221175] caller is debug_smp_processor_id+0x17/0x20
> > [ 2123.221214] CPU: 0 PID: 1733 Comm: bash Not tainted 5.16.0-rc1 #5
> > [ 2123.221218] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
> > [ 2123.221229] Call Trace:
> > [ 2123.221231] <TASK>
> > [ 2123.221235] dump_stack_lvl+0x5d/0x78
> > [ 2123.221252] dump_stack+0x10/0x12
> > [ 2123.221257] check_preemption_disabled+0xe4/0xf0
> > [ 2123.221266] debug_smp_processor_id+0x17/0x20
> > [ 2123.221271] rtrs_clt_update_all_stats+0x3b/0x70 [rtrs_client]
> > [ 2123.221285] rtrs_clt_read_req+0xc3/0x380 [rtrs_client]
> > [ 2123.221298] ? rtrs_clt_init_req+0xe3/0x120 [rtrs_client]
> > [ 2123.221321] rtrs_clt_request+0x1a7/0x320 [rtrs_client]
> > [ 2123.221340] ? 0xffffffffc0ab1000
> > [ 2123.221357] send_usr_msg+0xbf/0x160 [rnbd_client]
> > [ 2123.221370] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
> > [ 2123.221377] ? send_usr_msg+0x160/0x160 [rnbd_client]
> > [ 2123.221386] ? sg_alloc_table+0x27/0xb0
> > [ 2123.221395] ? sg_zero_buffer+0xd0/0xd0
> > [ 2123.221407] send_msg_sess_info+0xe9/0x180 [rnbd_client]
> > [ 2123.221413] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
> > [ 2123.221429] ? blk_mq_alloc_tag_set+0x2ef/0x370
> > [ 2123.221447] rnbd_clt_map_device+0xba8/0xcd0 [rnbd_client]
> > [ 2123.221462] ? send_msg_open+0x200/0x200 [rnbd_client]
> > [ 2123.221479] rnbd_clt_map_device_store+0x3e5/0x620 [rnbd_client
> >
> > To supress the calltrace, let's call get_cpu_ptr/put_cpu_ptr pair in
> > rtrs_clt_update_rdma_stats to disable preemption when accessing per-cpu
> > variable.
> >
> > Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
> > ---
> > drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> > index f7e459fe68be..6ff72f2b1a3a 100644
> > --- a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> > +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> > @@ -169,9 +169,10 @@ static inline void rtrs_clt_update_rdma_stats(struct rtrs_clt_stats *stats,
> > {
> > struct rtrs_clt_stats_pcpu *s;
> >
> > - s = this_cpu_ptr(stats->pcpu_stats);
> > + s = get_cpu_ptr(stats->pcpu_stats);
> > s->rdma.dir[d].cnt++;
> > s->rdma.dir[d].size_total += size;
> > + put_cpu_ptr(stats->pcpu_stats);
>
> I see that this_cpu_ptr() is used in many other places in rtrs-clt-stats.c,
> why do we need to change only one place?
Right, indeed. guoqing, mind to respin?
Thanks
>
> Thanks
>
> > }
> >
> > void rtrs_clt_update_all_stats(struct rtrs_clt_io_req *req, int dir)
> > --
> > 2.31.1
> >
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning
2021-11-22 8:20 ` Jinpu Wang
@ 2021-11-22 8:23 ` Guoqing Jiang
0 siblings, 0 replies; 5+ messages in thread
From: Guoqing Jiang @ 2021-11-22 8:23 UTC (permalink / raw)
To: Jinpu Wang, Leon Romanovsky; +Cc: haris.iqbal, jgg, linux-rdma
On 11/22/21 4:20 PM, Jinpu Wang wrote:
> On Mon, Nov 22, 2021 at 8:44 AM Leon Romanovsky <leon@kernel.org> wrote:
>> On Sun, Nov 21, 2021 at 10:22:23PM +0800, Guoqing Jiang wrote:
>>> With preemption enabled (CONFIG_DEBUG_PREEMPT=y), the following appeared
>>> when rnbd client tries to map remote block device.
>>>
>>> [ 2123.221071] BUG: using smp_processor_id() in preemptible [00000000] code: bash/1733
>>> [ 2123.221175] caller is debug_smp_processor_id+0x17/0x20
>>> [ 2123.221214] CPU: 0 PID: 1733 Comm: bash Not tainted 5.16.0-rc1 #5
>>> [ 2123.221218] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
>>> [ 2123.221229] Call Trace:
>>> [ 2123.221231] <TASK>
>>> [ 2123.221235] dump_stack_lvl+0x5d/0x78
>>> [ 2123.221252] dump_stack+0x10/0x12
>>> [ 2123.221257] check_preemption_disabled+0xe4/0xf0
>>> [ 2123.221266] debug_smp_processor_id+0x17/0x20
>>> [ 2123.221271] rtrs_clt_update_all_stats+0x3b/0x70 [rtrs_client]
>>> [ 2123.221285] rtrs_clt_read_req+0xc3/0x380 [rtrs_client]
>>> [ 2123.221298] ? rtrs_clt_init_req+0xe3/0x120 [rtrs_client]
>>> [ 2123.221321] rtrs_clt_request+0x1a7/0x320 [rtrs_client]
>>> [ 2123.221340] ? 0xffffffffc0ab1000
>>> [ 2123.221357] send_usr_msg+0xbf/0x160 [rnbd_client]
>>> [ 2123.221370] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
>>> [ 2123.221377] ? send_usr_msg+0x160/0x160 [rnbd_client]
>>> [ 2123.221386] ? sg_alloc_table+0x27/0xb0
>>> [ 2123.221395] ? sg_zero_buffer+0xd0/0xd0
>>> [ 2123.221407] send_msg_sess_info+0xe9/0x180 [rnbd_client]
>>> [ 2123.221413] ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
>>> [ 2123.221429] ? blk_mq_alloc_tag_set+0x2ef/0x370
>>> [ 2123.221447] rnbd_clt_map_device+0xba8/0xcd0 [rnbd_client]
>>> [ 2123.221462] ? send_msg_open+0x200/0x200 [rnbd_client]
>>> [ 2123.221479] rnbd_clt_map_device_store+0x3e5/0x620 [rnbd_client
>>>
>>> To supress the calltrace, let's call get_cpu_ptr/put_cpu_ptr pair in
>>> rtrs_clt_update_rdma_stats to disable preemption when accessing per-cpu
>>> variable.
>>>
>>> Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
>>> ---
>>> drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c | 3 ++-
>>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
>>> index f7e459fe68be..6ff72f2b1a3a 100644
>>> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
>>> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
>>> @@ -169,9 +169,10 @@ static inline void rtrs_clt_update_rdma_stats(struct rtrs_clt_stats *stats,
>>> {
>>> struct rtrs_clt_stats_pcpu *s;
>>>
>>> - s = this_cpu_ptr(stats->pcpu_stats);
>>> + s = get_cpu_ptr(stats->pcpu_stats);
>>> s->rdma.dir[d].cnt++;
>>> s->rdma.dir[d].size_total += size;
>>> + put_cpu_ptr(stats->pcpu_stats);
>> I see that this_cpu_ptr() is used in many other places in rtrs-clt-stats.c,
>> why do we need to change only one place?
> Right, indeed. guoqing, mind to respin?
I just see this calltrace, probably other paths are not triggered since
the connection can't be established.
Anyway, will send v2.
Thanks,
Guoqing
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-11-22 8:23 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-11-21 14:22 [PATCH] RDMA/rtrs: Call {get,put}_cpu_ptr to silence a debug kernel warning Guoqing Jiang
2021-11-22 7:25 ` Jinpu Wang
2021-11-22 7:44 ` Leon Romanovsky
2021-11-22 8:20 ` Jinpu Wang
2021-11-22 8:23 ` Guoqing Jiang
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