This provides the ability to inject artifical errors to memory hotplug notifier chain callbacks. It is controlled through debugfs interface under /sys/kernel/debug/notifier-error-inject/memory If the notifier call chain should be failed with some events notified, write the error code to "actions/<notifier event>/error". Example: Inject memory hotplug offline error (-12 == -ENOMEM) # cd /sys/kernel/debug/notifier-error-inject/memory # echo -12 > actions/MEM_GOING_OFFLINE/error # echo offline > /sys/devices/system/memory/memoryXXX/state bash: echo: write error: Cannot allocate memory Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			48 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			48 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/memory.h>
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#include "notifier-error-inject.h"
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static int priority;
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module_param(priority, int, 0);
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MODULE_PARM_DESC(priority, "specify memory notifier priority");
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static struct notifier_err_inject memory_notifier_err_inject = {
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	.actions = {
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		{ NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_ONLINE) },
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		{ NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_OFFLINE) },
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		{}
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	}
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};
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static struct dentry *dir;
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static int err_inject_init(void)
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{
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	int err;
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	dir = notifier_err_inject_init("memory", notifier_err_inject_dir,
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					&memory_notifier_err_inject, priority);
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	if (IS_ERR(dir))
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		return PTR_ERR(dir);
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	err = register_memory_notifier(&memory_notifier_err_inject.nb);
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	if (err)
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		debugfs_remove_recursive(dir);
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	return err;
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}
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static void err_inject_exit(void)
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{
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	unregister_memory_notifier(&memory_notifier_err_inject.nb);
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	debugfs_remove_recursive(dir);
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}
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module_init(err_inject_init);
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module_exit(err_inject_exit);
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MODULE_DESCRIPTION("memory notifier error injection module");
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
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