Re: [PATCH] kvm-userspace: Fix external modules for pre-2.6.27 UP kernels

[Jan Kiszka <jan.kiszka@siemens.com>]

Jan Kiszka wrote:
> When disabling SMP on kernels older than 2.6.27, the compat wrapping
> fails due to unresolved SMP dependencies. This patch fixes the build.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
> 
>  kernel/external-module-compat-comm.h |    2 +-
>  kernel/external-module-compat.c      |   15 +++++++++++++++
>  2 files changed, 16 insertions(+), 1 deletions(-)
> 
> diff --git a/kernel/external-module-compat-comm.h b/kernel/external-module-compat-comm.h
> index 981dc96..06af36d 100644
> --- a/kernel/external-module-compat-comm.h
> +++ b/kernel/external-module-compat-comm.h
> @@ -54,7 +54,7 @@
>  
>  int kvm_smp_call_function_single(int cpu, void (*func)(void *info),
>  				 void *info, int wait);
> -
> +#undef smp_call_function_single
>  #define smp_call_function_single kvm_smp_call_function_single
>  
>  #endif
> diff --git a/kernel/external-module-compat.c b/kernel/external-module-compat.c
> index c0a0355..823ce82 100644
> --- a/kernel/external-module-compat.c
> +++ b/kernel/external-module-compat.c
> @@ -86,11 +86,24 @@ int kvm_smp_call_function_single(int cpu, void (*func)(void *info),
>  
>  #include <linux/smp.h>
>  
> +#ifdef CONFIG_SMP
>  int kvm_smp_call_function_single(int cpu, void (*func)(void *info),
>  				 void *info, int wait)
>  {
>  	return smp_call_function_single(cpu, func, info, 0, wait);
>  }
> +#else /* !CONFIG_SMP */
> +int kvm_smp_call_function_single(int cpu, void (*func)(void *info),
> +				 void *info, int wait)
> +{
> +	WARN_ON(cpu != 0);
> +	local_irq_disable();
> +	func(info);
> +	local_irq_enable();
> +	return 0;
> +
> +}
> +#endif /* !CONFIG_SMP */
>  
>  #define smp_call_function_single kvm_smp_call_function_single
>  
> @@ -162,6 +175,7 @@ static void kvm_ack_smp_call(void *_data)
>  int kvm_smp_call_function_mask(cpumask_t mask,
>  			       void (*func) (void *info), void *info, int wait)
>  {
> +#ifdef CONFIG_SMP
>  	struct kvm_call_data_struct data;
>  	cpumask_t allbutself;
>  	int cpus;
> @@ -203,6 +217,7 @@ int kvm_smp_call_function_mask(cpumask_t mask,
>  	}
>  out:
>  	put_cpu();
> +#endif /* CONFIG_SMP */
>  	return 0;
>  }
>  

Still applies, still required.

Jan

-- 
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