Re: [Xen-devel] [PATCH] common: clean up taint logic

[George Dunlap <george.dunlap@xxxxxxxxxx>]

On 09/08/16 11:39, Jan Beulich wrote:
> Drop unused UNSAFE_SMP and BAD_PAGE flags. Style adjstments.
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> 
> --- a/xen/common/kernel.c
> +++ b/xen/common/kernel.c
> @@ -22,8 +22,6 @@
>  
>  enum system_state system_state = SYS_STATE_early_boot;
>  
> -int tainted;
> -
>  xen_commandline_t saved_cmdline;
>  
>  static void __init assign_integer_param(
> @@ -168,14 +166,15 @@ int __init parse_bool(const char *s)
>      return -1;
>  }
>  
> +unsigned int tainted;
> +
>  /**
>   *      print_tainted - return a string to represent the kernel taint state.
>   *
> - *  'S' - SMP with CPUs not designed for SMP.
> - *  'M' - Machine had a machine check experience.
> - *  'B' - System has hit bad_page.
>   *  'C' - Console output is synchronous.
> + *  'E' - An error (e.g. a machine check exceptions) has been injected.
>   *  'H' - HVM forced emulation prefix is permitted.
> + *  'M' - Machine had a machine check experience.

The wording here seems to imply that M -> E; but I don't see anything
which adds ERROR_INJECT.  Are you  planning on adding this at some point
in the future?

 -George

>   *
>   *      The string is overwritten by the next call to print_taint().
>   */
> @@ -183,11 +182,10 @@ char *print_tainted(char *str)
>  {
>      if ( tainted )
>      {
> -        snprintf(str, TAINT_STRING_MAX_LEN, "Tainted: %c%c%c%c%c",
> -                 tainted & TAINT_UNSAFE_SMP ? 'S' : ' ',
> +        snprintf(str, TAINT_STRING_MAX_LEN, "Tainted: %c%c%c%c",
>                   tainted & TAINT_MACHINE_CHECK ? 'M' : ' ',
> -                 tainted & TAINT_BAD_PAGE ? 'B' : ' ',
>                   tainted & TAINT_SYNC_CONSOLE ? 'C' : ' ',
> +                 tainted & TAINT_ERROR_INJECT ? 'E' : ' ',
>                   tainted & TAINT_HVM_FEP ? 'H' : ' ');
>      }
>      else
> @@ -198,7 +196,7 @@ char *print_tainted(char *str)
>      return str;
>  }
>  
> -void add_taint(unsigned flag)
> +void add_taint(unsigned int flag)
>  {
>      tainted |= flag;
>  }
> --- a/xen/include/xen/lib.h
> +++ b/xen/include/xen/lib.h
> @@ -137,16 +137,14 @@ unsigned long long parse_size_and_unit(c
>  
>  uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c);
>  
> -#define TAINT_UNSAFE_SMP                (1<<0)
> -#define TAINT_MACHINE_CHECK             (1<<1)
> -#define TAINT_BAD_PAGE                  (1<<2)
> -#define TAINT_SYNC_CONSOLE              (1<<3)
> -#define TAINT_ERROR_INJECT              (1<<4)
> -#define TAINT_HVM_FEP                   (1<<5)
> -extern int tainted;
> +#define TAINT_SYNC_CONSOLE              (1u << 0)
> +#define TAINT_MACHINE_CHECK             (1u << 1)
> +#define TAINT_ERROR_INJECT              (1u << 2)
> +#define TAINT_HVM_FEP                   (1u << 3)
> +extern unsigned int tainted;
>  #define TAINT_STRING_MAX_LEN            20
>  extern char *print_tainted(char *str);
> -extern void add_taint(unsigned);
> +extern void add_taint(unsigned int taint);
>  
>  struct cpu_user_regs;
>  void dump_execstate(struct cpu_user_regs *);
> 
> 
> 


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel