FAILED: patch "[PATCH] io_uring: only flush workqueues on fileset removal" failed to apply to 5.3-stable tree

FAILED: patch "[PATCH] io_uring: only flush workqueues on fileset removal" failed to apply to 5.3-stable tree

[gregkh]

The patch below does not apply to the 5.3-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8a99734081775c012a4a6c442fdef0379fe52bdf Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Wed, 9 Oct 2019 14:40:13 -0600
Subject: [PATCH] io_uring: only flush workqueues on fileset removal

We should not remove the workqueue, we just need to ensure that the
workqueues are synced. The workqueues are torn down on ctx removal.

Cc: stable@vger.kernel.org
Fixes: 6b06314c47e1 ("io_uring: add file set registration")
Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index ceb3497bdd2a..2c44648217bd 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2866,8 +2866,12 @@ static void io_finish_async(struct io_ring_ctx *ctx)
 static void io_destruct_skb(struct sk_buff *skb)
 {
 	struct io_ring_ctx *ctx = skb->sk->sk_user_data;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ctx->sqo_wq); i++)
+		if (ctx->sqo_wq[i])
+			flush_workqueue(ctx->sqo_wq[i]);
 
-	io_finish_async(ctx);
 	unix_destruct_scm(skb);
 }
 

Re: FAILED: patch "[PATCH] io_uring: only flush workqueues on fileset removal" failed to apply to 5.3-stable tree

[Greg KH]

On Wed, Oct 16, 2019 at 09:04:43AM -0700, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 5.3-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.
> 
> thanks,
> 
> greg k-h
> 
> ------------------ original commit in Linus's tree ------------------
> 
> >From 8a99734081775c012a4a6c442fdef0379fe52bdf Mon Sep 17 00:00:00 2001
> From: Jens Axboe <axboe@kernel.dk>
> Date: Wed, 9 Oct 2019 14:40:13 -0600
> Subject: [PATCH] io_uring: only flush workqueues on fileset removal
> 
> We should not remove the workqueue, we just need to ensure that the
> workqueues are synced. The workqueues are torn down on ctx removal.
> 
> Cc: stable@vger.kernel.org
> Fixes: 6b06314c47e1 ("io_uring: add file set registration")
> Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> 
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index ceb3497bdd2a..2c44648217bd 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -2866,8 +2866,12 @@ static void io_finish_async(struct io_ring_ctx *ctx)
>  static void io_destruct_skb(struct sk_buff *skb)
>  {
>  	struct io_ring_ctx *ctx = skb->sk->sk_user_data;
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(ctx->sqo_wq); i++)
> +		if (ctx->sqo_wq[i])
> +			flush_workqueue(ctx->sqo_wq[i]);
>  
> -	io_finish_async(ctx);
>  	unix_destruct_scm(skb);
>  }
>  
> 

This fails to build as sqo_wq is a pointer in 5.3, not an arrary.
Backporting that array change feels "big" for 5.3, is that needed here,
or can this be fixed differently?

thanks,

greg k-h

Re: FAILED: patch "[PATCH] io_uring: only flush workqueues on fileset removal" failed to apply to 5.3-stable tree

[Jens Axboe]

On 10/16/19 10:13 AM, Greg KH wrote:
> On Wed, Oct 16, 2019 at 09:04:43AM -0700, gregkh@linuxfoundation.org wrote:
>>
>> The patch below does not apply to the 5.3-stable tree.
>> If someone wants it applied there, or to any other stable or longterm
>> tree, then please email the backport, including the original git commit
>> id to <stable@vger.kernel.org>.
>>
>> thanks,
>>
>> greg k-h
>>
>> ------------------ original commit in Linus's tree ------------------
>>
>> >From 8a99734081775c012a4a6c442fdef0379fe52bdf Mon Sep 17 00:00:00 2001
>> From: Jens Axboe <axboe@kernel.dk>
>> Date: Wed, 9 Oct 2019 14:40:13 -0600
>> Subject: [PATCH] io_uring: only flush workqueues on fileset removal
>>
>> We should not remove the workqueue, we just need to ensure that the
>> workqueues are synced. The workqueues are torn down on ctx removal.
>>
>> Cc: stable@vger.kernel.org
>> Fixes: 6b06314c47e1 ("io_uring: add file set registration")
>> Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
>> Signed-off-by: Jens Axboe <axboe@kernel.dk>
>>
>> diff --git a/fs/io_uring.c b/fs/io_uring.c
>> index ceb3497bdd2a..2c44648217bd 100644
>> --- a/fs/io_uring.c
>> +++ b/fs/io_uring.c
>> @@ -2866,8 +2866,12 @@ static void io_finish_async(struct io_ring_ctx *ctx)
>>   static void io_destruct_skb(struct sk_buff *skb)
>>   {
>>   	struct io_ring_ctx *ctx = skb->sk->sk_user_data;
>> +	int i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(ctx->sqo_wq); i++)
>> +		if (ctx->sqo_wq[i])
>> +			flush_workqueue(ctx->sqo_wq[i]);
>>   
>> -	io_finish_async(ctx);
>>   	unix_destruct_scm(skb);
>>   }
>>   
>>
> 
> This fails to build as sqo_wq is a pointer in 5.3, not an arrary.
> Backporting that array change feels "big" for 5.3, is that needed here,
> or can this be fixed differently?

Yeah, we don't need to do that. It's just a pointer in 5.3, not an
array of pointers, so the below should be all we need for 5.3 (and
5.2/5.1).


diff --git a/fs/io_uring.c b/fs/io_uring.c
index cfb48bd088e1..e05f302cfb41 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2564,7 +2564,8 @@ static void io_destruct_skb(struct sk_buff *skb)
 {
 	struct io_ring_ctx *ctx = skb->sk->sk_user_data;
 
-	io_finish_async(ctx);
+	if (ctx->sqo_wq)
+		flush_workqueue(ctx->sqo_wq);
 	unix_destruct_scm(skb);
 }
 

-- 
Jens Axboe

Re: FAILED: patch "[PATCH] io_uring: only flush workqueues on fileset removal" failed to apply to 5.3-stable tree

[Greg KH]

On Wed, Oct 16, 2019 at 10:20:16AM -0600, Jens Axboe wrote:
> On 10/16/19 10:13 AM, Greg KH wrote:
> > On Wed, Oct 16, 2019 at 09:04:43AM -0700, gregkh@linuxfoundation.org wrote:
> >>
> >> The patch below does not apply to the 5.3-stable tree.
> >> If someone wants it applied there, or to any other stable or longterm
> >> tree, then please email the backport, including the original git commit
> >> id to <stable@vger.kernel.org>.
> >>
> >> thanks,
> >>
> >> greg k-h
> >>
> >> ------------------ original commit in Linus's tree ------------------
> >>
> >> >From 8a99734081775c012a4a6c442fdef0379fe52bdf Mon Sep 17 00:00:00 2001
> >> From: Jens Axboe <axboe@kernel.dk>
> >> Date: Wed, 9 Oct 2019 14:40:13 -0600
> >> Subject: [PATCH] io_uring: only flush workqueues on fileset removal
> >>
> >> We should not remove the workqueue, we just need to ensure that the
> >> workqueues are synced. The workqueues are torn down on ctx removal.
> >>
> >> Cc: stable@vger.kernel.org
> >> Fixes: 6b06314c47e1 ("io_uring: add file set registration")
> >> Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
> >> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> >>
> >> diff --git a/fs/io_uring.c b/fs/io_uring.c
> >> index ceb3497bdd2a..2c44648217bd 100644
> >> --- a/fs/io_uring.c
> >> +++ b/fs/io_uring.c
> >> @@ -2866,8 +2866,12 @@ static void io_finish_async(struct io_ring_ctx *ctx)
> >>   static void io_destruct_skb(struct sk_buff *skb)
> >>   {
> >>   	struct io_ring_ctx *ctx = skb->sk->sk_user_data;
> >> +	int i;
> >> +
> >> +	for (i = 0; i < ARRAY_SIZE(ctx->sqo_wq); i++)
> >> +		if (ctx->sqo_wq[i])
> >> +			flush_workqueue(ctx->sqo_wq[i]);
> >>   
> >> -	io_finish_async(ctx);
> >>   	unix_destruct_scm(skb);
> >>   }
> >>   
> >>
> > 
> > This fails to build as sqo_wq is a pointer in 5.3, not an arrary.
> > Backporting that array change feels "big" for 5.3, is that needed here,
> > or can this be fixed differently?
> 
> Yeah, we don't need to do that. It's just a pointer in 5.3, not an
> array of pointers, so the below should be all we need for 5.3 (and
> 5.2/5.1).

5.2/5.1 are long end-of-life, but this change looks sane.  I'll go queue
it up for 5.3.y, thanks for the patch!

greg k-h

Re: FAILED: patch "[PATCH] io_uring: only flush workqueues on fileset removal" failed to apply to 5.3-stable tree

[Jens Axboe]

On 10/16/19 10:33 AM, Greg KH wrote:
> On Wed, Oct 16, 2019 at 10:20:16AM -0600, Jens Axboe wrote:
>> On 10/16/19 10:13 AM, Greg KH wrote:
>>> On Wed, Oct 16, 2019 at 09:04:43AM -0700, gregkh@linuxfoundation.org wrote:
>>>>
>>>> The patch below does not apply to the 5.3-stable tree.
>>>> If someone wants it applied there, or to any other stable or longterm
>>>> tree, then please email the backport, including the original git commit
>>>> id to <stable@vger.kernel.org>.
>>>>
>>>> thanks,
>>>>
>>>> greg k-h
>>>>
>>>> ------------------ original commit in Linus's tree ------------------
>>>>
>>>> >From 8a99734081775c012a4a6c442fdef0379fe52bdf Mon Sep 17 00:00:00 2001
>>>> From: Jens Axboe <axboe@kernel.dk>
>>>> Date: Wed, 9 Oct 2019 14:40:13 -0600
>>>> Subject: [PATCH] io_uring: only flush workqueues on fileset removal
>>>>
>>>> We should not remove the workqueue, we just need to ensure that the
>>>> workqueues are synced. The workqueues are torn down on ctx removal.
>>>>
>>>> Cc: stable@vger.kernel.org
>>>> Fixes: 6b06314c47e1 ("io_uring: add file set registration")
>>>> Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
>>>> Signed-off-by: Jens Axboe <axboe@kernel.dk>
>>>>
>>>> diff --git a/fs/io_uring.c b/fs/io_uring.c
>>>> index ceb3497bdd2a..2c44648217bd 100644
>>>> --- a/fs/io_uring.c
>>>> +++ b/fs/io_uring.c
>>>> @@ -2866,8 +2866,12 @@ static void io_finish_async(struct io_ring_ctx *ctx)
>>>>    static void io_destruct_skb(struct sk_buff *skb)
>>>>    {
>>>>    	struct io_ring_ctx *ctx = skb->sk->sk_user_data;
>>>> +	int i;
>>>> +
>>>> +	for (i = 0; i < ARRAY_SIZE(ctx->sqo_wq); i++)
>>>> +		if (ctx->sqo_wq[i])
>>>> +			flush_workqueue(ctx->sqo_wq[i]);
>>>>    
>>>> -	io_finish_async(ctx);
>>>>    	unix_destruct_scm(skb);
>>>>    }
>>>>    
>>>>
>>>
>>> This fails to build as sqo_wq is a pointer in 5.3, not an arrary.
>>> Backporting that array change feels "big" for 5.3, is that needed here,
>>> or can this be fixed differently?
>>
>> Yeah, we don't need to do that. It's just a pointer in 5.3, not an
>> array of pointers, so the below should be all we need for 5.3 (and
>> 5.2/5.1).
> 
> 5.2/5.1 are long end-of-life, but this change looks sane.  I'll go queue
> it up for 5.3.y, thanks for the patch!

Thanks Greg!

-- 
Jens Axboe