Patch "percpu: don't forget to free the temporary struct pcpu_alloc_info" has been added to the 4.14-stable tree

Patch "percpu: don't forget to free the temporary struct pcpu_alloc_info" has been added to the 4.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    percpu: don't forget to free the temporary struct pcpu_alloc_info

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     percpu-don-t-forget-to-free-the-temporary-struct-pcpu_alloc_info.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Wed Dec 20 18:17:52 CET 2017
From: Nicolas Pitre <nicolas.pitre@linaro.org>
Date: Tue, 3 Oct 2017 18:29:49 -0400
Subject: percpu: don't forget to free the temporary struct pcpu_alloc_info

From: Nicolas Pitre <nicolas.pitre@linaro.org>


[ Upstream commit 438a50618095061920d3a30d4c5ca1ef2e0ff860 ]

Unlike the SMP case, the !SMP case does not free the memory for struct
pcpu_alloc_info allocated in setup_per_cpu_areas(). And to give it a
chance of being reused by the page allocator later, align it to a page
boundary just like its size.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Dennis Zhou <dennisszhou@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 mm/percpu.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1856,7 +1856,7 @@ struct pcpu_alloc_info * __init pcpu_all
 			  __alignof__(ai->groups[0].cpu_map[0]));
 	ai_size = base_size + nr_units * sizeof(ai->groups[0].cpu_map[0]);
 
-	ptr = memblock_virt_alloc_nopanic(PFN_ALIGN(ai_size), 0);
+	ptr = memblock_virt_alloc_nopanic(PFN_ALIGN(ai_size), PAGE_SIZE);
 	if (!ptr)
 		return NULL;
 	ai = ptr;
@@ -2719,6 +2719,7 @@ void __init setup_per_cpu_areas(void)
 
 	if (pcpu_setup_first_chunk(ai, fc) < 0)
 		panic("Failed to initialize percpu areas.");
+	pcpu_free_alloc_info(ai);
 }
 
 #endif	/* CONFIG_SMP */


Patches currently in stable-queue which might be from nicolas.pitre@linaro.org are

queue-4.14/percpu-don-t-forget-to-free-the-temporary-struct-pcpu_alloc_info.patch

Re: Patch "percpu: don't forget to free the temporary struct pcpu_alloc_info" has been added to the 4.14-stable tree

[Nicolas Pitre]

On Wed, 20 Dec 2017, gregkh@linuxfoundation.org wrote:

> This is a note to let you know that I've just added the patch titled
> 
>     percpu: don't forget to free the temporary struct pcpu_alloc_info
> to the 4.14-stable tree which can be found at:
>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> 
> The filename of the patch is:
>      percpu-don-t-forget-to-free-the-temporary-struct-pcpu_alloc_info.patch
> and it can be found in the queue-4.14 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.

If you consider this patch worthy enough for the stable tree, then you 
should also pick commit abee210500ed otherwise the CRIS architecture 
will regress.


> From foo@baz Wed Dec 20 18:17:52 CET 2017
> From: Nicolas Pitre <nicolas.pitre@linaro.org>
> Date: Tue, 3 Oct 2017 18:29:49 -0400
> Subject: percpu: don't forget to free the temporary struct pcpu_alloc_info
> 
> From: Nicolas Pitre <nicolas.pitre@linaro.org>
> 
> 
> [ Upstream commit 438a50618095061920d3a30d4c5ca1ef2e0ff860 ]
> 
> Unlike the SMP case, the !SMP case does not free the memory for struct
> pcpu_alloc_info allocated in setup_per_cpu_areas(). And to give it a
> chance of being reused by the page allocator later, align it to a page
> boundary just like its size.
> 
> Signed-off-by: Nicolas Pitre <nico@linaro.org>
> Acked-by: Dennis Zhou <dennisszhou@gmail.com>
> Signed-off-by: Tejun Heo <tj@kernel.org>
> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  mm/percpu.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> --- a/mm/percpu.c
> +++ b/mm/percpu.c
> @@ -1856,7 +1856,7 @@ struct pcpu_alloc_info * __init pcpu_all
>  			  __alignof__(ai->groups[0].cpu_map[0]));
>  	ai_size = base_size + nr_units * sizeof(ai->groups[0].cpu_map[0]);
>  
> -	ptr = memblock_virt_alloc_nopanic(PFN_ALIGN(ai_size), 0);
> +	ptr = memblock_virt_alloc_nopanic(PFN_ALIGN(ai_size), PAGE_SIZE);
>  	if (!ptr)
>  		return NULL;
>  	ai = ptr;
> @@ -2719,6 +2719,7 @@ void __init setup_per_cpu_areas(void)
>  
>  	if (pcpu_setup_first_chunk(ai, fc) < 0)
>  		panic("Failed to initialize percpu areas.");
> +	pcpu_free_alloc_info(ai);
>  }
>  
>  #endif	/* CONFIG_SMP */
> 
> 
> Patches currently in stable-queue which might be from nicolas.pitre@linaro.org are
> 
> queue-4.14/percpu-don-t-forget-to-free-the-temporary-struct-pcpu_alloc_info.patch
> 

Re: Patch "percpu: don't forget to free the temporary struct pcpu_alloc_info" has been added to the 4.14-stable tree

[alexander.levin]

On Wed, Dec 20, 2017 at 01:41:01PM -0500, Nicolas Pitre wrote:
>On Wed, 20 Dec 2017, gregkh@linuxfoundation.org wrote:
>
>> This is a note to let you know that I've just added the patch titled
>>
>>     percpu: don't forget to free the temporary struct pcpu_alloc_info
>> to the 4.14-stable tree which can be found at:
>>     https://urldefense.proofpoint.com/v2/url?u=http-3A__www.kernel.org_git_-3Fp-3Dlinux_kernel_git_stable_stable-2Dqueue.git-3Ba-3Dsummary&d=DwIBAg&c=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ&r=bUtaaC9mlBij4OjEG_D-KPul_335azYzfC4Rjgomobo&m=qnNDf4IeHRQ_ffqQXDeVcI9CCT5Pq7EmTmp5xbKWg-I&s=KgCwQ9E3kx6oTOuZ75TsmUM6dqxn_zrSgFwENCasLi8&e=
>>
>> The filename of the patch is:
>>      percpu-don-t-forget-to-free-the-temporary-struct-pcpu_alloc_info.patch
>> and it can be found in the queue-4.14 subdirectory.
>>
>> If you, or anyone else, feels it should not be added to the stable tree,
>> please let <stable@vger.kernel.org> know about it.
>
>If you consider this patch worthy enough for the stable tree, then you
>should also pick commit abee210500ed otherwise the CRIS architecture
>will regress.

In this case I'd rather just drop this commit, at least until this
issue is fixed (rather than ducttaped) upstream. Thanks Nicolas!

-- 

Thanks,
Sasha

Re: Patch "percpu: don't forget to free the temporary struct pcpu_alloc_info" has been added to the 4.14-stable tree

[Greg KH]

On Wed, Dec 20, 2017 at 01:41:01PM -0500, Nicolas Pitre wrote:
> On Wed, 20 Dec 2017, gregkh@linuxfoundation.org wrote:
> 
> > This is a note to let you know that I've just added the patch titled
> > 
> >     percpu: don't forget to free the temporary struct pcpu_alloc_info
> > to the 4.14-stable tree which can be found at:
> >     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> > 
> > The filename of the patch is:
> >      percpu-don-t-forget-to-free-the-temporary-struct-pcpu_alloc_info.patch
> > and it can be found in the queue-4.14 subdirectory.
> > 
> > If you, or anyone else, feels it should not be added to the stable tree,
> > please let <stable@vger.kernel.org> know about it.
> 
> If you consider this patch worthy enough for the stable tree, then you 
> should also pick commit abee210500ed otherwise the CRIS architecture 
> will regress.

Sadly, CRIS is dead, but yeah, it's not good to kill it earlier than
expected :)

I'll take Sasha's patch to drop this, thanks.

greg k-h

Re: Patch "percpu: don't forget to free the temporary struct pcpu_alloc_info" has been added to the 4.14-stable tree

[Nicolas Pitre]

On Thu, 21 Dec 2017, Greg KH wrote:

> On Wed, Dec 20, 2017 at 01:41:01PM -0500, Nicolas Pitre wrote:
> > On Wed, 20 Dec 2017, gregkh@linuxfoundation.org wrote:
> > 
> > > If you, or anyone else, feels it should not be added to the stable tree,
> > > please let <stable@vger.kernel.org> know about it.
> > 
> > If you consider this patch worthy enough for the stable tree, then you 
> > should also pick commit abee210500ed otherwise the CRIS architecture 
> > will regress.
> 
> Sadly, CRIS is dead, but yeah, it's not good to kill it earlier than
> expected :)

Well, some people noticed soon enough after this patch hit mainline that 
their CRIS setup didn't boot any longer. A good way to know if some 
architecture is really dead is to break it!  ;-)


Nicolas