df43ba7d7f
commit c04e72700f2293013dab40208e809369378f224c upstream. In the event that random_get_entropy() can't access a cycle counter or similar, falling back to returning 0 is really not the best we can do. Instead, at least calling random_get_entropy_fallback() would be preferable, because that always needs to return _something_, even falling back to jiffies eventually. It's not as though random_get_entropy_fallback() is super high precision or guaranteed to be entropic, but basically anything that's not zero all the time is better than returning zero all the time. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
28 lines
912 B
C
28 lines
912 B
C
/* Copyright Altera Corporation (C) 2014. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License, version 2,
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* as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#ifndef _ASM_NIOS2_TIMEX_H
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#define _ASM_NIOS2_TIMEX_H
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typedef unsigned long cycles_t;
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extern cycles_t get_cycles(void);
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#define get_cycles get_cycles
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#define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback())
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#endif
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