Re: [XEN PATCH][for-4.19 v3 1/8] xen: add declarations for variables where needed

[Julien Grall <julien@xxxxxxx>]

Hi,

On 19/10/2023 14:39, Nicola Vetrini wrote:
> Some variables with external linkage used in C code do not have
> a visible declaration where they are defined. Providing such
> declaration also resolves violations of MISRA C:2012 Rule 8.4.
The commit message doesn't match the code in several places.

> Signed-off-by: Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>
> ---
> Changes in v2:
> - make xenpf_lock static on ARM
> Changes in v3:
> - moved back code from symbols.h to symbols.c
> - dropped two declarations, now deviated
> ---
>   xen/arch/arm/include/asm/setup.h  | 3 +++
>   xen/arch/arm/include/asm/smp.h    | 3 +++
>   xen/arch/arm/platform_hypercall.c | 2 +-
>   xen/arch/x86/cpu/mcheck/mce.c     | 6 +++---
>   xen/arch/x86/irq.c                | 2 +-
>   xen/include/xen/symbols.h         | 1 +
>   6 files changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/xen/arch/arm/include/asm/setup.h b/xen/arch/arm/include/asm/setup.h
> index 98af6f55f5a0..2a2d6114f2eb 100644
> --- a/xen/arch/arm/include/asm/setup.h
> +++ b/xen/arch/arm/include/asm/setup.h
> @@ -184,9 +184,12 @@ int map_range_to_domain(const struct dt_device_node *dev,
>   extern lpae_t boot_pgtable[XEN_PT_LPAE_ENTRIES];
>   
>   #ifdef CONFIG_ARM_64
> +extern lpae_t boot_first[XEN_PT_LPAE_ENTRIES];
>   extern lpae_t boot_first_id[XEN_PT_LPAE_ENTRIES];
>   #endif
> +extern lpae_t boot_second[XEN_PT_LPAE_ENTRIES];
>   extern lpae_t boot_second_id[XEN_PT_LPAE_ENTRIES];
> +extern lpae_t boot_third[XEN_PT_LPAE_ENTRIES * XEN_NR_ENTRIES(2)];
>   extern lpae_t boot_third_id[XEN_PT_LPAE_ENTRIES];
>   
>   /* Find where Xen will be residing at runtime and return a PT entry */
> diff --git a/xen/arch/arm/include/asm/smp.h b/xen/arch/arm/include/asm/smp.h
> index 4fabdf5310d8..28bf24a01d95 100644
> --- a/xen/arch/arm/include/asm/smp.h
> +++ b/xen/arch/arm/include/asm/smp.h
> @@ -6,6 +6,9 @@
>   #include <asm/current.h>
>   #endif
>   
> +extern struct init_info init_data;
> +extern unsigned long smp_up_cpu;
> +
>   DECLARE_PER_CPU(cpumask_var_t, cpu_sibling_mask);
>   DECLARE_PER_CPU(cpumask_var_t, cpu_core_mask);
>   
> diff --git a/xen/arch/arm/platform_hypercall.c b/xen/arch/arm/platform_hypercall.c
> index 743687a30390..fde4bc3e5809 100644
> --- a/xen/arch/arm/platform_hypercall.c
> +++ b/xen/arch/arm/platform_hypercall.c
> @@ -17,7 +17,7 @@
>   #include <asm/current.h>
>   #include <asm/event.h>
>   
> -DEFINE_SPINLOCK(xenpf_lock);
> +static DEFINE_SPINLOCK(xenpf_lock);
The commit message suggest we would add an external definition but here 
you add a 'static'. I am fine the static but it needs to clarify.
>   
>   long do_platform_op(XEN_GUEST_HANDLE_PARAM(xen_platform_op_t) u_xenpf_op)
>   {
> diff --git a/xen/arch/x86/cpu/mcheck/mce.c b/xen/arch/x86/cpu/mcheck/mce.c
> index 6141b7eb9cf1..e855f958030d 100644
> --- a/xen/arch/x86/cpu/mcheck/mce.c
> +++ b/xen/arch/x86/cpu/mcheck/mce.c
> @@ -1682,13 +1682,13 @@ long do_mca(XEN_GUEST_HANDLE_PARAM(xen_mc_t) u_xen_mc)
>       return ret;
>   }
>   
> -int mcinfo_dumpped;
> +static int mcinfo_dumped;
Same for the static. But you are also renaming the variable without 
explanation. Yes I know there are a typo, the point here is the commit 
message needs to reflect what you are doing.
>   static int cf_check x86_mcinfo_dump_panic(mctelem_cookie_t mctc)
>   {
>       struct mc_info *mcip = mctelem_dataptr(mctc);
>   
>       x86_mcinfo_dump(mcip);
> -    mcinfo_dumpped++;
> +    mcinfo_dumped++;
>   
>       return 0;
>   }
> @@ -1702,7 +1702,7 @@ static void mc_panic_dump(void)
>       for_each_online_cpu(cpu)
>           mctelem_process_deferred(cpu, x86_mcinfo_dump_panic,
>                                    mctelem_has_deferred_lmce(cpu));
> -    dprintk(XENLOG_ERR, "End dump mc_info, %x mcinfo dumped\n", 
> mcinfo_dumpped);
> +    dprintk(XENLOG_ERR, "End dump mc_info, %x mcinfo dumped\n", mcinfo_dumped);
>   }
>   
>   void mc_panic(const char *s)
> diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
> index 6abfd8162120..604dba94b052 100644
> --- a/xen/arch/x86/irq.c
> +++ b/xen/arch/x86/irq.c
> @@ -43,7 +43,7 @@ int __read_mostly opt_irq_vector_map = 
> OPT_IRQ_VECTOR_MAP_DEFAULT;
>   static unsigned char __read_mostly irq_max_guests;
>   integer_param("irq-max-guests", irq_max_guests);
>   
> -vmask_t global_used_vector_map;
> +static vmask_t global_used_vector_map;
Same for the static.

>   
>   struct irq_desc __read_mostly *irq_desc = NULL;
>   
> diff --git a/xen/include/xen/symbols.h b/xen/include/xen/symbols.h
> index 20bbb28ef226..1b2863663aa0 100644
> --- a/xen/include/xen/symbols.h
> +++ b/xen/include/xen/symbols.h
> @@ -33,4 +33,5 @@ struct symbol_offset {
>       uint32_t stream; /* .. in the compressed stream.*/
>       uint32_t addr;   /* .. and in the fixed size address array. */
>   };
> +
>   #endif /*_XEN_SYMBOLS_H*/
Cheers,

--
Julien Grall