linux-next: objtool hang/loop?

linux-next: objtool hang/loop?

[Randy Dunlap]

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Hi Josh & Peter,

Yesterday (2021-07-27), one of my x86_64 randconfig build ran for
over 2 hours (it's a slow core i5 laptop and spinning rust media).
I killed it and reran the .config file today on linux-next-20210728.
I killed this one after 30 minutes on its last message:
  OBJTOOL vmlinux.o

This is a .config with # CONFIG_MODULES is not set.
vmlinux.o is 253 MB in size.
I see that using verbose make (V=1) won't help me any here.

The problematic (if it is a problem: maybe I didn't wait long
enough?) .config file is attached.  The gzipped vmlinux.o file is at:
  http://www.infradead.org/~rdunlap/vmlinux.o.gz

If there is a problem, I can test any patches...

thanks.
-- 
~Randy


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Re: linux-next: objtool hang/loop?

[Josh Poimboeuf]

On Wed, Jul 28, 2021 at 07:25:21PM -0700, Randy Dunlap wrote:
> Hi Josh & Peter,
> 
> Yesterday (2021-07-27), one of my x86_64 randconfig build ran for
> over 2 hours (it's a slow core i5 laptop and spinning rust media).
> I killed it and reran the .config file today on linux-next-20210728.
> I killed this one after 30 minutes on its last message:
>   OBJTOOL vmlinux.o
> 
> This is a .config with # CONFIG_MODULES is not set.
> vmlinux.o is 253 MB in size.
> I see that using verbose make (V=1) won't help me any here.
> 
> The problematic (if it is a problem: maybe I didn't wait long
> enough?) .config file is attached.  The gzipped vmlinux.o file is at:
>   http://www.infradead.org/~rdunlap/vmlinux.o.gz
> 
> If there is a problem, I can test any patches...

Hi Randy,

I'm guessing your laptop doesn't have a lot of RAM.  I ran

  /usr/bin/time -v tools/objtool/objtool check --noinstr --vmlinux --no-fp --uaccess vmlinux.o

It showed a max RSS of 6.5GB.

Can you try this patch from Peter?  It halves the memory usage.

  https://lkml.kernel.org/r/20210507164925.GC54801@worktop.programming.kicks-ass.net

-- 
Josh

Re: linux-next: objtool hang/loop?

[Randy Dunlap]

On 8/4/21 11:34 AM, Josh Poimboeuf wrote:
> On Wed, Jul 28, 2021 at 07:25:21PM -0700, Randy Dunlap wrote:
>> Hi Josh & Peter,
>>
>> Yesterday (2021-07-27), one of my x86_64 randconfig build ran for
>> over 2 hours (it's a slow core i5 laptop and spinning rust media).
>> I killed it and reran the .config file today on linux-next-20210728.
>> I killed this one after 30 minutes on its last message:
>>    OBJTOOL vmlinux.o
>>
>> This is a .config with # CONFIG_MODULES is not set.
>> vmlinux.o is 253 MB in size.
>> I see that using verbose make (V=1) won't help me any here.
>>
>> The problematic (if it is a problem: maybe I didn't wait long
>> enough?) .config file is attached.  The gzipped vmlinux.o file is at:
>>    http://www.infradead.org/~rdunlap/vmlinux.o.gz
>>
>> If there is a problem, I can test any patches...
> 
> Hi Randy,
> 
> I'm guessing your laptop doesn't have a lot of RAM.  I ran

Hey, it has a whopping 6 GB of RAM. :)

>    /usr/bin/time -v tools/objtool/objtool check --noinstr --vmlinux --no-fp --uaccess vmlinux.o
> 
> It showed a max RSS of 6.5GB.
> 
> Can you try this patch from Peter?  It halves the memory usage.
> 
>    https://lkml.kernel.org/r/20210507164925.GC54801@worktop.programming.kicks-ass.net

Yes, that fixes the problem for me. Thanks.

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>

-- 
~Randy

Re: linux-next: objtool hang/loop?

[Peter Zijlstra]

On Wed, Aug 04, 2021 at 11:34:19AM -0700, Josh Poimboeuf wrote:
> Can you try this patch from Peter?  It halves the memory usage.
> 
>   https://lkml.kernel.org/r/20210507164925.GC54801@worktop.programming.kicks-ass.net

Oh hey, Josh is back :-)

Just in case you missed it (I'm guessing your inbox is as big a mess as
mine is), that patch is part of the below series that is awaiting your
feedback :-)

  https://lkml.kernel.org/r/20210624094059.886075998@infradead.org