[gentoo-user] linux-headers-3.5 with 3.4 kernel?

[gentoo-user] linux-headers-3.5 with 3.4 kernel?

[Nikos Chantziaras]

Portage now installs sys-kernel/linux-headers-3.5. 
sys-kernel/gentoo-sources is at 3.4.5.

Is it even adviced to do that, installing 3.5 headers and running a 3.4 
kernel?  This sounds like a bad idea to me.

Re: [gentoo-user] linux-headers-3.5 with 3.4 kernel?

[Florian Philipp]

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Am 23.07.2012 16:16, schrieb Nikos Chantziaras:
> Portage now installs sys-kernel/linux-headers-3.5.
> sys-kernel/gentoo-sources is at 3.4.5.
> 
> Is it even adviced to do that, installing 3.5 headers and running a 3.4
> kernel?  This sounds like a bad idea to me.
> 
> 

Honestly, I cannot give you a satisfying explanation, but

a) I came across this:
http://forums.gentoo.org/viewtopic-t-570319-start-0.html

b) I was told the same years ago and never had issues.

c) until you re-emerge glibc nothing changes anyway.

d) your current glibc won't use new features, anyway (I guess)

e) and even then, forward/backward compatibility in kernel headers and
glibc are very good.

Regards,
Florian Philipp


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Re: [gentoo-user] linux-headers-3.5 with 3.4 kernel?

[Paul Hartman]

On Mon, Jul 23, 2012 at 11:46 AM, Florian Philipp <lists@binarywings.net> wrote:
> Am 23.07.2012 16:16, schrieb Nikos Chantziaras:
>> Portage now installs sys-kernel/linux-headers-3.5.
>> sys-kernel/gentoo-sources is at 3.4.5.
>>
>> Is it even adviced to do that, installing 3.5 headers and running a 3.4
>> kernel?  This sounds like a bad idea to me.
>>
>>
>
> Honestly, I cannot give you a satisfying explanation, but
>
> a) I came across this:
> http://forums.gentoo.org/viewtopic-t-570319-start-0.html
>
> b) I was told the same years ago and never had issues.
>
> c) until you re-emerge glibc nothing changes anyway.
>
> d) your current glibc won't use new features, anyway (I guess)
>
> e) and even then, forward/backward compatibility in kernel headers and
> glibc are very good.

I have no official information either, but I always mask headers
greater than the version of kernel I'm using right now, just because
it feels wrong to me. there are about two dozen packages on my system
that depend on os-headers or linux-headers, so I don't get comfort
from "basically only glibc cares" statements. But maybe I'm just
worrying for no good reason. :)

Re: [gentoo-user] linux-headers-3.5 with 3.4 kernel?

[Helmut Jarausch]

On 07/23/2012 04:16:41 PM, Nikos Chantziaras wrote:
> Portage now installs sys-kernel/linux-headers-3.5.  
> sys-kernel/gentoo-sources is at 3.4.5.
> 
> Is it even adviced to do that, installing 3.5 headers and running a  
> 3.4 kernel?  This sounds like a bad idea to me.
> 

Why are you not using the 3.5.0 kernel (vanilla-sources has it). It  
contains some import fixes.
Helmut.

Re: [gentoo-user] linux-headers-3.5 with 3.4 kernel?

[Paul Hartman]

On Mon, Jul 23, 2012 at 3:01 PM, Helmut Jarausch
<jarausch@igpm.rwth-aachen.de> wrote:
> On 07/23/2012 04:16:41 PM, Nikos Chantziaras wrote:
>>
>> Portage now installs sys-kernel/linux-headers-3.5.
>> sys-kernel/gentoo-sources is at 3.4.5.
>>
>> Is it even adviced to do that, installing 3.5 headers and running a 3.4
>> kernel?  This sounds like a bad idea to me.
>>
>
> Why are you not using the 3.5.0 kernel (vanilla-sources has it). It contains
> some import fixes.

3.5.0 was not in portage tree last time I did sync a few hours ago. I
guess it is new. :)

[gentoo-user] Re: linux-headers-3.5 with 3.4 kernel?

[»Q«]

On Mon, 23 Jul 2012 17:16:41 +0300
Nikos Chantziaras <realnc@gmail.com> wrote:

> Portage now installs sys-kernel/linux-headers-3.5. 
> sys-kernel/gentoo-sources is at 3.4.5.
> 
> Is it even adviced to do that, installing 3.5 headers and running a
> 3.4 kernel?  This sounds like a bad idea to me.

As I read the glibc faq, linux-headers are backwards-compatible as far
as glibc is concerned;  that is, newer linux-headers still have
everything needed to make glibc work with older kernels.  And I assume
that holds for other packages which need linux-headers, not just glibc.

Whether my understanding of why is correct or not, the glibc folks do
recommend using the latest linux-headers, even if your kernel is older.

<https://www.gnu.org/software/libc/documentation.html> links to 
<http://sourceware.org/glibc/wiki/FAQ#What_version_of_the_Linux_kernel_headers_should_be_used.3F>.

Re: [gentoo-user] Re: linux-headers-3.5 with 3.4 kernel?

[Oszkár Ocsenás]

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I totally agree with Q
2012.07.23. 23:15, "»Q«" <boxcars@gmx.net> ezt írta:

> On Mon, 23 Jul 2012 17:16:41 +0300
> Nikos Chantziaras <realnc@gmail.com> wrote:
>
> > Portage now installs sys-kernel/linux-headers-3.5.
> > sys-kernel/gentoo-sources is at 3.4.5.
> >
> > Is it even adviced to do that, installing 3.5 headers and running a
> > 3.4 kernel?  This sounds like a bad idea to me.
>
> As I read the glibc faq, linux-headers are backwards-compatible as far
> as glibc is concerned;  that is, newer linux-headers still have
> everything needed to make glibc work with older kernels.  And I assume
> that holds for other packages which need linux-headers, not just glibc.
>
> Whether my understanding of why is correct or not, the glibc folks do
> recommend using the latest linux-headers, even if your kernel is older.
>
> <https://www.gnu.org/software/libc/documentation.html> links to
> <
> http://sourceware.org/glibc/wiki/FAQ#What_version_of_the_Linux_kernel_headers_should_be_used.3F
> >.
>
>
>

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[gentoo-user] Re: linux-headers-3.5 with 3.4 kernel?

[Nikos Chantziaras]

On 23/07/12 23:01, Helmut Jarausch wrote:
> On 07/23/2012 04:16:41 PM, Nikos Chantziaras wrote:
>> Portage now installs sys-kernel/linux-headers-3.5.
>> sys-kernel/gentoo-sources is at 3.4.5.
>>
>> Is it even adviced to do that, installing 3.5 headers and running a
>> 3.4 kernel?  This sounds like a bad idea to me.
>>
>
> Why are you not using the 3.5.0 kernel

Because BFS doesn't support it yet.