[PATCH] kvm: external module: support building against Windriver 2.0 (kernel 2.6.21)

[PATCH] kvm: external module: support building against Windriver 2.0 (kernel 2.6.21)

[Bernhard Kohl]

This is needed to compile kvm in a Windriver 2.0 distribution
(kernel 2.6.21). This kernel has an include file marker.h, but
trace_mark is not defined there. So the compat code in
kernel/include-compat/linux/marker.h is not included.

Signed-off-by: Bernhard Kohl <bernhard.kohl@nsn.com>
---
 kernel/external-module-compat-comm.h |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/kernel/external-module-compat-comm.h
b/kernel/external-module-compat-comm.h
index a14cea2..e40501e 100644
--- a/kernel/external-module-compat-comm.h
+++ b/kernel/external-module-compat-comm.h
@@ -25,6 +25,10 @@
 #  undef CONFIG_KVM_TRACE
 #endif
 
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,21)
+#define trace_mark(args...) ((void)0)
+#endif
+
 /*
  * 2.6.16 does not have GFP_NOWAIT
  */
-- 
1.6.0.6

Re: [PATCH] kvm: external module: support building against Windriver 2.0 (kernel 2.6.21)

[Jan Kiszka]

Bernhard Kohl wrote:
> This is needed to compile kvm in a Windriver 2.0 distribution
> (kernel 2.6.21). This kernel has an include file marker.h, but
> trace_mark is not defined there. So the compat code in
> kernel/include-compat/linux/marker.h is not included.

I bet this is because Wind River patched some variant of LTTng into
their kernel.

However, I'm unsure if supporting significantly modified distribution
kernels is in the scope of this compat layer. If it is ok for the
maintainers, you should try to make the test more Wind River specific
(did you check that there is no side-effect for normal <= 2.6.21
kernels?) and maybe add a comment.

Jan

> 
> Signed-off-by: Bernhard Kohl <bernhard.kohl@nsn.com>
> ---
>  kernel/external-module-compat-comm.h |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/kernel/external-module-compat-comm.h
> b/kernel/external-module-compat-comm.h
> index a14cea2..e40501e 100644
> --- a/kernel/external-module-compat-comm.h
> +++ b/kernel/external-module-compat-comm.h
> @@ -25,6 +25,10 @@
>  #  undef CONFIG_KVM_TRACE
>  #endif
>  
> +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,21)
> +#define trace_mark(args...) ((void)0)
> +#endif
> +
>  /*
>   * 2.6.16 does not have GFP_NOWAIT
>   */

-- 
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux

Re: [PATCH] kvm: external module: support building against Windriver 2.0 (kernel 2.6.21)

[Bernhard Kohl]

Jan Kiszka <jan.kiszka <at> siemens.com> writes:

> 
> I bet this is because Wind River patched some variant of LTTng into
> their kernel.
> 
> However, I'm unsure if supporting significantly modified distribution
> kernels is in the scope of this compat layer. If it is ok for the
> maintainers, you should try to make the test more Wind River specific
> (did you check that there is no side-effect for normal <= 2.6.21
> kernels?) and maybe add a comment.

No I didn't check this with other <= 2.6.21 kernels.

Bernhard

Re: [PATCH] kvm: external module: support building against Windriver 2.0 (kernel 2.6.21)

[Avi Kivity]

Jan Kiszka wrote:
> Bernhard Kohl wrote:
>   
>> This is needed to compile kvm in a Windriver 2.0 distribution
>> (kernel 2.6.21). This kernel has an include file marker.h, but
>> trace_mark is not defined there. So the compat code in
>> kernel/include-compat/linux/marker.h is not included.
>>     
>
> I bet this is because Wind River patched some variant of LTTng into
> their kernel.
>
> However, I'm unsure if supporting significantly modified distribution
> kernels is in the scope of this compat layer. 

Yes, for example we support the RHEL 5 series, which significantly 
deviates from plain 2.6.18.

> If it is ok for the
> maintainers, you should try to make the test more Wind River specific
> (did you check that there is no side-effect for normal <= 2.6.21
> kernels?) and maybe add a comment.
>   

Best would be to check for a Wind River kernel as this is likely to 
break on mainline Linux.



-- 
error compiling committee.c: too many arguments to function

Re: [PATCH] kvm: external module: support building against Windriver 2.0 (kernel 2.6.21)

[Bernhard Kohl]

Avi Kivity <avi <at> redhat.com> writes:
> 
> Best would be to check for a Wind River kernel as this is likely to 
> break on mainline Linux.
> 

OK, I see, that's more complicated. We are currently thinking about to upgrade
our systems to an up-to-date kernel version. Then this patch is no longer
required.