From patchwork Sat Apr 23 21:26:22 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 12824705 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8209C433F5 for ; Sat, 23 Apr 2022 21:28:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237241AbiDWVbv (ORCPT ); Sat, 23 Apr 2022 17:31:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44804 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237319AbiDWVbm (ORCPT ); Sat, 23 Apr 2022 17:31:42 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6ABB7517C2; Sat, 23 Apr 2022 14:27:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 22C00B80DAD; Sat, 23 Apr 2022 21:27:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27B1AC385A9; Sat, 23 Apr 2022 21:27:47 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="R1K0841c" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1650749266; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8zi1lCm2O0jts5CCIlALtKrvY8ZmOWq+bxyFytkOqdo=; b=R1K0841cbI3psirmjcGLTETqb7GkvJsrasORGSXNDAGhXjkmmiGYmgYfB6b0YEQCeAP2sP ELckmhhiReAhzyOW3zxDEQ5+3jE0AsePACDGCvFJLdE7KJF44+HqMBHAAs/E+xi8AHNrnW nTgpgHhm1T6No8Jj7o9YPPT8fkZ8mg0= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id a54b8660 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO); Sat, 23 Apr 2022 21:27:46 +0000 (UTC) From: "Jason A. Donenfeld" To: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, tglx@linutronix.de, arnd@arndb.de Cc: "Jason A. Donenfeld" , Max Filippov Subject: [PATCH v6 16/17] xtensa: use fallback for random_get_entropy() instead of zero Date: Sat, 23 Apr 2022 23:26:22 +0200 Message-Id: <20220423212623.1957011-17-Jason@zx2c4.com> In-Reply-To: <20220423212623.1957011-1-Jason@zx2c4.com> References: <20220423212623.1957011-1-Jason@zx2c4.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org 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. This is accomplished by just including the asm-generic code like on other architectures, which means we can get rid of the empty stub function here. Cc: Thomas Gleixner Cc: Arnd Bergmann Acked-by: Max Filippov Signed-off-by: Jason A. Donenfeld --- arch/xtensa/include/asm/timex.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/xtensa/include/asm/timex.h b/arch/xtensa/include/asm/timex.h index 233ec75e60c6..3f2462f2d027 100644 --- a/arch/xtensa/include/asm/timex.h +++ b/arch/xtensa/include/asm/timex.h @@ -29,10 +29,6 @@ extern unsigned long ccount_freq; -typedef unsigned long long cycles_t; - -#define get_cycles() (0) - void local_timer_setup(unsigned cpu); /* @@ -59,4 +55,6 @@ static inline void set_linux_timer (unsigned long ccompare) xtensa_set_sr(ccompare, SREG_CCOMPARE + LINUX_TIMER); } +#include + #endif /* _XTENSA_TIMEX_H */