Attachment #223763 for bug #309425




	default 1200 if ALPHA_RAWHIDE
	default 1024

config ALPHA_UAC_SYSCTL
	bool "Configure UAC policy via sysctl"
	depends on SYSCTL
	default y
	---help---
	  Configuring the UAC (unaligned access control) policy on a Linux
	  system usually involves setting a compile time define. If you say
	  Y here, you will be able to modify the UAC policy at runtime using
	  the /proc interface.

	  The UAC policy defines the action Linux should take when an
	  unaligned memory access occurs. The action can include printing a
	  warning message (NOPRINT), sending a signal to the offending
	  program to help developers debug their applications (SIGBUS), or
	  disabling the transparent fixing (NOFIX).

	  The sysctls will be initialized to the compile-time defined UAC
	  policy. You can change these manually, or with the sysctl(8)
	  userspace utility.

	  To disable the warning messages at runtime, you would use

	    echo 1 > /proc/sys/kernel/uac/noprint

	  This is pretty harmless. Say Y if you're not sure.

source "drivers/pci/Kconfig"
source "drivers/eisa/Kconfig"





			   "t10", "t11", "ra", "pv", "at", "gp", "sp", "zero"};
#endif

#ifdef CONFIG_ALPHA_UAC_SYSCTL

#include <linux/sysctl.h>

static int enabled_noprint = 0;
static int enabled_sigbus = 0;
static int enabled_nofix = 0;

ctl_table uac_table[] = {
   	{
		.ctl_name 	= CTL_UNNUMBERED,
		.procname 	= "noprint", 
		.data 		= &enabled_noprint, 
		.maxlen 	= sizeof (int), 
		.mode 		= 0644, 
		.proc_handler = &proc_dointvec,
	},
   	{
		.ctl_name 	= CTL_UNNUMBERED,
		.procname 	= "sigbus", 
		.data 		= &enabled_sigbus, 
		.maxlen 	= sizeof (int), 
		.mode 		= 0644, 
		.proc_handler = &proc_dointvec,
	},
   	{
		.ctl_name 	= CTL_UNNUMBERED,
		.procname 	= "nofix", 
		.data 		= &enabled_nofix, 
		.maxlen 	= sizeof (int), 
		.mode 		= 0644, 
		.proc_handler = &proc_dointvec,
	},
	{ .ctl_name = 0 }
};

static int __init init_uac_sysctl(void)
{
   /* Initialize sysctls with the #defined UAC policy */
   enabled_noprint = (test_thread_flag (TIF_UAC_NOPRINT)) ? 1 : 0;
   enabled_sigbus = (test_thread_flag (TIF_UAC_SIGBUS)) ? 1 : 0;
   enabled_nofix = (test_thread_flag (TIF_UAC_NOFIX)) ? 1 : 0;
   return 0;
}
#endif

static void
dik_show_code(unsigned int *pc)
{

	/* Check the UAC bits to decide what the user wants us to do
	   with the unaliged access.  */

#ifndef CONFIG_ALPHA_UAC_SYSCTL
	if (!test_thread_flag (TIF_UAC_NOPRINT)) {
#else  /* CONFIG_ALPHA_UAC_SYSCTL */
	if (!(enabled_noprint)) {
#endif /* CONFIG_ALPHA_UAC_SYSCTL */
		if (cnt >= 5 && time_after(jiffies, last_time + 5 * HZ)) {
			cnt = 0;
		}

		}
		last_time = jiffies;
	}
#ifndef CONFIG_ALPHA_UAC_SYSCTL
	if (test_thread_flag (TIF_UAC_SIGBUS))
#else  /* CONFIG_ALPHA_UAC_SYSCTL */
   if (enabled_sigbus)
#endif /* CONFIG_ALPHA_UAC_SYSCTL */
		goto give_sigbus;
	/* Not sure why you'd want to use this, but... */
#ifndef CONFIG_ALPHA_UAC_SYSCTL
	if (test_thread_flag (TIF_UAC_NOFIX))
#else  /* CONFIG_ALPHA_UAC_SYSCTL */
   if (enabled_nofix)
#endif /* CONFIG_ALPHA_UAC_SYSCTL */
		return;

	/* Don't bother reading ds in the access check since we already

	wrent(entSys, 5);
	wrent(entDbg, 6);
}

#ifdef CONFIG_ALPHA_UAC_SYSCTL
	__initcall(init_uac_sysctl);
#endif

Lines 239-244 static struct ctl_table root_table[] = { Link Here

(-)a/kernel/sysctl.c (+9 lines)
239	{ }	239	{ }
240	};	240	};
241		241
		242	#ifdef CONFIG_ALPHA_UAC_SYSCTL
		243	{
		244	.ctl_name = CTL_UNNUMBERED,
		245	.procname = "uac",
		246	.mode = 0555,
		247	.child = uac_table,
		248	},
		249	#endif /* CONFIG_ALPHA_UAC_SYSCTL */
		250
242	#ifdef CONFIG_SCHED_DEBUG	251	#ifdef CONFIG_SCHED_DEBUG
243	static int min_sched_granularity_ns = 100000; /* 100 usecs */	252	static int min_sched_granularity_ns = 100000; /* 100 usecs */
244	static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */	253	static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */

Return to bug 309425

Lines 624-629 config HZ Link Here

(-)linux-2.6.26-gentoo/arch/alpha/Kconfig (+26 lines)
624	default 1200 if ALPHA_RAWHIDE	624	default 1200 if ALPHA_RAWHIDE
625	default 1024	625	default 1024
626		626
		627	config ALPHA_UAC_SYSCTL
		628	bool "Configure UAC policy via sysctl"
		629	depends on SYSCTL
		630	default y
		631	---help---
		632	Configuring the UAC (unaligned access control) policy on a Linux
		633	system usually involves setting a compile time define. If you say
		634	Y here, you will be able to modify the UAC policy at runtime using
		635	the /proc interface.
		636
		637	The UAC policy defines the action Linux should take when an
		638	unaligned memory access occurs. The action can include printing a
		639	warning message (NOPRINT), sending a signal to the offending
		640	program to help developers debug their applications (SIGBUS), or
		641	disabling the transparent fixing (NOFIX).
		642
		643	The sysctls will be initialized to the compile-time defined UAC
		644	policy. You can change these manually, or with the sysctl(8)
		645	userspace utility.
		646
		647	To disable the warning messages at runtime, you would use
		648
		649	echo 1 > /proc/sys/kernel/uac/noprint
		650
		651	This is pretty harmless. Say Y if you're not sure.
		652
627	source "drivers/pci/Kconfig"	653	source "drivers/pci/Kconfig"
628	source "drivers/eisa/Kconfig"	654	source "drivers/eisa/Kconfig"
629		655

Lines 103-108 static char * ireg_name[] = {"v0", "t0", Link Here

(-)linux-2.6.26-gentoo/arch/alpha/kernel/traps.c (+62 lines)
103	"t10", "t11", "ra", "pv", "at", "gp", "sp", "zero"};	103	"t10", "t11", "ra", "pv", "at", "gp", "sp", "zero"};
104	#endif	104	#endif
105		105
		106	#ifdef CONFIG_ALPHA_UAC_SYSCTL
		107
		108	#include <linux/sysctl.h>
		109
		110	static int enabled_noprint = 0;
		111	static int enabled_sigbus = 0;
		112	static int enabled_nofix = 0;
		113
		114	ctl_table uac_table[] = {
		115	{
		116	.ctl_name = CTL_UNNUMBERED,
		117	.procname = "noprint",
		118	.data = &enabled_noprint,
		119	.maxlen = sizeof (int),
		120	.mode = 0644,
		121	.proc_handler = &proc_dointvec,
		122	},
		123	{
		124	.ctl_name = CTL_UNNUMBERED,
		125	.procname = "sigbus",
		126	.data = &enabled_sigbus,
		127	.maxlen = sizeof (int),
		128	.mode = 0644,
		129	.proc_handler = &proc_dointvec,
		130	},
		131	{
		132	.ctl_name = CTL_UNNUMBERED,
		133	.procname = "nofix",
		134	.data = &enabled_nofix,
		135	.maxlen = sizeof (int),
		136	.mode = 0644,
		137	.proc_handler = &proc_dointvec,
		138	},
		139	{ .ctl_name = 0 }
		140	};
		141
		142	static int __init init_uac_sysctl(void)
		143	{
		144	/* Initialize sysctls with the #defined UAC policy */
		145	enabled_noprint = (test_thread_flag (TIF_UAC_NOPRINT)) ? 1 : 0;
		146	enabled_sigbus = (test_thread_flag (TIF_UAC_SIGBUS)) ? 1 : 0;
		147	enabled_nofix = (test_thread_flag (TIF_UAC_NOFIX)) ? 1 : 0;
		148	return 0;
		149	}
		150	#endif
		151
106	static void	152	static void
107	dik_show_code(unsigned int *pc)	153	dik_show_code(unsigned int *pc)
108	{	154	{
Lines 782-788 do_entUnaUser(void __user * va, unsigned Link Here
782	/* Check the UAC bits to decide what the user wants us to do	828	/* Check the UAC bits to decide what the user wants us to do
783	with the unaliged access. */	829	with the unaliged access. */
784		830
		831	#ifndef CONFIG_ALPHA_UAC_SYSCTL
785	if (!test_thread_flag (TIF_UAC_NOPRINT)) {	832	if (!test_thread_flag (TIF_UAC_NOPRINT)) {
		833	#else /* CONFIG_ALPHA_UAC_SYSCTL */
		834	if (!(enabled_noprint)) {
		835	#endif /* CONFIG_ALPHA_UAC_SYSCTL */
786	if (cnt >= 5 && time_after(jiffies, last_time + 5 * HZ)) {	836	if (cnt >= 5 && time_after(jiffies, last_time + 5 * HZ)) {
787	cnt = 0;	837	cnt = 0;
788	}	838	}
Lines 793-802 do_entUnaUser(void __user * va, unsigned Link Here
793	}	843	}
794	last_time = jiffies;	844	last_time = jiffies;
795	}	845	}
		846	#ifndef CONFIG_ALPHA_UAC_SYSCTL
796	if (test_thread_flag (TIF_UAC_SIGBUS))	847	if (test_thread_flag (TIF_UAC_SIGBUS))
		848	#else /* CONFIG_ALPHA_UAC_SYSCTL */
		849	if (enabled_sigbus)
		850	#endif /* CONFIG_ALPHA_UAC_SYSCTL */
797	goto give_sigbus;	851	goto give_sigbus;
798	/* Not sure why you'd want to use this, but... */	852	/* Not sure why you'd want to use this, but... */
		853	#ifndef CONFIG_ALPHA_UAC_SYSCTL
799	if (test_thread_flag (TIF_UAC_NOFIX))	854	if (test_thread_flag (TIF_UAC_NOFIX))
		855	#else /* CONFIG_ALPHA_UAC_SYSCTL */
		856	if (enabled_nofix)
		857	#endif /* CONFIG_ALPHA_UAC_SYSCTL */
800	return;	858	return;
801		859
802	/* Don't bother reading ds in the access check since we already	860	/* Don't bother reading ds in the access check since we already
Lines 1091-1093 trap_init(void) Link Here
1091	wrent(entSys, 5);	1149	wrent(entSys, 5);
1092	wrent(entDbg, 6);	1150	wrent(entDbg, 6);
1093	}	1151	}
		1152
		1153	#ifdef CONFIG_ALPHA_UAC_SYSCTL
		1154	__initcall(init_uac_sysctl);
		1155	#endif