Commit 4036c7d3 authored by Chris Metcalf's avatar Chris Metcalf
Browse files

tile: don't call show_regs_print_info() with corrupt current 



We use the validate_current() API to make sure that "current" seems
plausible before using it.  With the new show_regs_print_info()
API, we want to check that current is OK before calling it, since
otherwise we will end up in a recursive panic.

Signed-off-by: default avatarChris Metcalf <cmetcalf@tilera.com>
parent 6fbeee29

arch/tile/kernel/process.c

+5 −3
Original line number Diff line number Diff line
@@ -226,19 +226,20 @@ int get_unalign_ctl(struct task_struct *tsk, unsigned long adr) 
			(unsigned int __user *)adr);

}



static struct task_struct corrupt_current = { .comm = "<corrupt>" };



/*

 * Return "current" if it looks plausible, or else a pointer to a dummy.

 * This can be helpful if we are just trying to emit a clean panic.

 */

struct task_struct *validate_current(void)

{

	static struct task_struct corrupt = { .comm = "<corrupt>" };

	struct task_struct *tsk = current;

	if (unlikely((unsigned long)tsk < PAGE_OFFSET ||

		     (high_memory && (void *)tsk > high_memory) ||

		     ((unsigned long)tsk & (__alignof__(*tsk) - 1)) != 0)) {

		pr_err("Corrupt 'current' %p (sp %#lx)\n", tsk, stack_pointer);

		tsk = &corrupt;

		tsk = &corrupt_current;

	}

	return tsk;

}
@@ -589,6 +590,7 @@ void show_regs(struct pt_regs *regs) 
	int i;



	pr_err("\n");

	if (tsk != &corrupt_current)

		show_regs_print_info(KERN_ERR);

#ifdef __tilegx__

	for (i = 0; i < 17; i++)

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