Re: aprint_* used outside autoconfiguration step

[Brian Buhrow <buhrow%nfbcal.org@localhost>]

	Hello.  I'm a little confused by the goal of this change?  If there
are are errors worth printing messages about, shouldn't the author of the
error message have a reasonable expectation that their message will get
printed via the available kernel printing facilities?  I certainly expect
if I'm writing a kernel module, that if I call a print routine, my message
should turn up rather than being ignored.

-thanks
-Brian

On Feb 19, 10:49am, Christos Zoulas wrote:
} Subject: aprint_* used outside autoconfiguration step
} 
} Hi,
} 
} I've noticed that now the "autoconfiguration print" error messages
} are printing "autoconfiguration error: " we have a situation where
} aprint_ calls are happening outside the autoconfiguration process.
} This is confusing. What makes this difficult to fix is:
} 
} 	1. Some of the calls can happen during the autoconfiguration
} 	   phase and also later (during normal operations). For example
} 	   the iffoo_init() routine and its children calls.
} 	2. We don't have a non-autoconfig-related family of printf
} 	   calls to handle errors outside autoconfiguration.
} 
} I propose to go for the simplest fix for now, which is to only print
} "autoconfiguration error: " during the autoconfiguration process (i.e.
} once autoconfiguration is done, to skip printing it. This again is
} wrong in some cases (hotplug), but something simplistic such as the
} following might take care of the majority of the cases:
} 
} Index: subr_prf.c
} ===================================================================
} RCS file: /cvsroot/src/sys/kern/subr_prf.c,v
} retrieving revision 1.176
} diff -u -u -r1.176 subr_prf.c
} --- subr_prf.c	14 Jan 2019 19:21:54 -0000	1.176
} +++ subr_prf.c	19 Feb 2019 15:48:26 -0000
} @@ -105,6 +105,7 @@
}  extern	struct tty *constty;	/* pointer to console "window" tty */
}  extern	int log_open;	/* subr_log: is /dev/klog open? */
}  extern	krndsource_t	rnd_printf_source;
} +extern int config_pending;
}  const	char *panicstr; /* arg to first call to panic (used as a flag
}  			   to indicate that panic has already been called). */
}  struct cpu_info *paniccpu;	/* cpu that first paniced */
} @@ -865,7 +866,8 @@
}  
}  	if (prefix)
}  		kprintf_internal("%s: ", flags, NULL, NULL, prefix);
} -	kprintf_internal("autoconfiguration error: ", TOLOG, NULL, NULL);
} +	if (config_pending)
} +		kprintf_internal("autoconfiguration error: ", TOLOG, NULL, NULL);
}  	kprintf(fmt, flags, NULL, NULL, ap);
}  
}  	kprintf_unlock();
} Index: subr_autoconf.c
} ===================================================================
} RCS file: /cvsroot/src/sys/kern/subr_autoconf.c,v
} retrieving revision 1.265
} diff -u -u -r1.265 subr_autoconf.c
} --- subr_autoconf.c	1 Dec 2018 02:08:16 -0000	1.265
} +++ subr_autoconf.c	19 Feb 2019 15:48:26 -0000
} @@ -224,7 +224,7 @@
}  static int alldevs_nwrite = 0;
}  static bool alldevs_garbage = false;
}  
} -static int config_pending;		/* semaphore for mountroot */
} +int config_pending;		/* semaphore for mountroot */
}  static kmutex_t config_misc_lock;
}  static kcondvar_t config_misc_cv;
}  
} 
} christos
>-- End of excerpt from Christos Zoulas