[RFC PATCH] ARM Fix /usr/bin/xargs: etags: Argument list too long

[RFC PATCH] ARM Fix /usr/bin/xargs: etags: Argument list too long

[David Cullen]

Patch applies to

    commit 42a579a0f960081cd16fc945036e4780c3ad3202

When running "make ARCH=arm TAGS" in a chroot using qemu-arm-static,
the following message is emitted:

    [user@host:/home/work/linux]: make ARCH=arm TAGS
      GEN     TAGS
    /usr/bin/xargs: etags: Argument list too long

This can be fixed by by passing "-L 1024" to xargs in scripts/tags.sh.

The "1024" was a guess. A value of "3862" changes the message to

    /usr/bin/xargs: argument list too long

Using "2048" also fixes the problem. However, I don't know how much
headroom that leaves

Does anyone know why the argument lists must be shorter for ARM? All
of the documentation I have available says that 4096 should be the
limit.

Signed-off-by: David Cullen <david.cullen@koe-americas.com>
---
 scripts/tags.sh |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/tags.sh b/scripts/tags.sh
index cff8faa..7f4ebb3 100755
--- a/scripts/tags.sh
+++ b/scripts/tags.sh
@@ -121,7 +121,7 @@ dogtags()

 exuberant()
 {
-       all_sources | xargs $1 -a                               \
+       all_sources | xargs -L 1024 $1 -a                       \
        -I __initdata,__exitdata,__acquires,__releases          \
        -I __read_mostly,____cacheline_aligned                  \
        -I ____cacheline_aligned_in_smp                         \
--
1.7.9.5

Re: [RFC PATCH] ARM Fix /usr/bin/xargs: etags: Argument list too long

[Michal Marek]

Dne 8.8.2012 16:32, David Cullen napsal(a):
> Patch applies to
> 
>     commit 42a579a0f960081cd16fc945036e4780c3ad3202
> 
> When running "make ARCH=arm TAGS" in a chroot using qemu-arm-static,
> the following message is emitted:
> 
>     [user@host:/home/work/linux]: make ARCH=arm TAGS
>       GEN     TAGS
>     /usr/bin/xargs: etags: Argument list too long
> 
> This can be fixed by by passing "-L 1024" to xargs in scripts/tags.sh.
> 
> The "1024" was a guess. A value of "3862" changes the message to
> 
>     /usr/bin/xargs: argument list too long
> 
> Using "2048" also fixes the problem. However, I don't know how much
> headroom that leaves
> 
> Does anyone know why the argument lists must be shorter for ARM? All
> of the documentation I have available says that 4096 should be the
> limit.

This looks like a bug in xargs, it should make sure that the commandline
fits into ARG_MAX. BTW, a better workaround would be to use the -s
option, which limits the size of the argument list.

Michal

Re: [RFC PATCH] ARM Fix /usr/bin/xargs: etags: Argument list too long

[David Cullen]

On 8/8/2012 10:41 AM, Michal Marek wrote:
> Dne 8.8.2012 16:32, David Cullen napsal(a):
>> Patch applies to
>>
>>     commit 42a579a0f960081cd16fc945036e4780c3ad3202
>>
>> When running "make ARCH=arm TAGS" in a chroot using qemu-arm-static,
>> the following message is emitted:
>>
>>     [user@host:/home/work/linux]: make ARCH=arm TAGS
>>       GEN     TAGS
>>     /usr/bin/xargs: etags: Argument list too long
>>
>> This can be fixed by by passing "-L 1024" to xargs in scripts/tags.sh.
>>
>> The "1024" was a guess. A value of "3862" changes the message to
>>
>>     /usr/bin/xargs: argument list too long
>>
>> Using "2048" also fixes the problem. However, I don't know how much
>> headroom that leaves
>>
>> Does anyone know why the argument lists must be shorter for ARM? All
>> of the documentation I have available says that 4096 should be the
>> limit.
> 
> This looks like a bug in xargs, it should make sure that the commandline
> fits into ARG_MAX.

Actually, it appears to be caused by the combination of
qemu-arm-static and xargs. When I run "make ARCH=arm TAGS" on an ARM
target, I do not see the problem.

> BTW, a better workaround would be to use the -s option, which
> limits the size of the argument list.

That works.

I'll submit another RFC patch.

-- 
Thank you,
David Cullen