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s390/traps: panic() instead of die() on translation exception

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In case of a translation exception the page tables are corrupted. If the
exception handler then calls die() which again calls show_regs()
-> show_code() -> copy_from_user(), the kernel may access the same memory
location again and generates yet another translation exception. Which in turn
will lead to a deadlock on the die_lock spinlock, which the kernel tries to
grab recursively.

Given that the page tables are corrupted anyway, if we see such an exception,
let's simply panic.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens 2015-02-18 14:17:14 +01:00 committed by Martin Schwidefsky
parent 86cd741bc6
commit e1d12d70f7
1 changed files with 1 additions and 1 deletions
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2
arch/s390/kernel/traps.c
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@ -174,7 +174,7 @@ static inline void do_fp_trap(struct pt_regs *regs, int fpc)
void translation_exception(struct pt_regs *regs)
{
/* May never happen. */
die(regs, "Translation exception");
panic("Translation exception");
}
void illegal_op(struct pt_regs *regs)