Message ID | 20220413115411.21489-11-Jason@zx2c4.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show
Return-Path: <linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org> X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2F164C433EF for <linux-riscv@archiver.kernel.org>; Wed, 13 Apr 2022 12:02:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=uVEep19F3PoO1VWyevm/+bJEAEY+2RWNe405/iqoIu8=; b=pcEf744retU6F8 RRVeqUvIataH1+Ys1SIYYP09vn2rMp1QdLMGslBnWfGBVaQ+JLXklUpaW+19CVkw3fYkczDNgdKYh 3OV0ieD2eyY/UhS8kqJrwdOEJ2To52/e1Uxd1GuHMw16YExOSJMPOhRgfhYA6bxIiw3w2Z9kc6Z9O YQPkrHb0/NOJYyzr/TMginUnV4f8jG176rsZFQazlvR3hnUyLESTIPPr9FhR+76a6b6ufyweTVEya lze8PjY/zCo3RzsJCIWYZ1agImKhiegrWqKslk7pkno4iq5RSnOIAnAs4PewKqPDPVcvvggnm/0z9 WO6XK7tLXr7xb6s8ngzQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nebhE-000sdH-Mc; Wed, 13 Apr 2022 12:02:04 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nebbX-000pep-Gl; Wed, 13 Apr 2022 11:56:14 +0000 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 dfw.source.kernel.org (Postfix) with ESMTPS id EB50161DF7; Wed, 13 Apr 2022 11:56:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D5ECC385A3; Wed, 13 Apr 2022 11:56:06 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="VDxKufAb" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1649850965; 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=gMuiTScdp7c+tPntikHvEFRo+YYqSeslWu8YJFI7ND8=; b=VDxKufAbcpZHe2UGxTIl2aDRHpkYNyjPH0PxxC+TaXgvtBCQtp10eZ9NvscTR0YI3Mdej/ Z/6prrXtJi1o2nDPsMXdIm7kQ7cft3qANs6xSlBlIvn4V862uLlz3rSGh6z17OM4oAvG5x 7bACYuAs17/Ya2d5ga5fVxf+CmmzrZk= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id c9127ee5 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO); Wed, 13 Apr 2022 11:56:05 +0000 (UTC) From: "Jason A. Donenfeld" <Jason@zx2c4.com> To: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, tglx@linutronix.de, arnd@arndb.de Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>, Theodore Ts'o <tytso@mit.edu>, Dominik Brodowski <linux@dominikbrodowski.net>, Russell King <linux@armlinux.org.uk>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>, Geert Uytterhoeven <geert@linux-m68k.org>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, Paul Walmsley <paul.walmsley@sifive.com>, Palmer Dabbelt <palmer@dabbelt.com>, Albert Ou <aou@eecs.berkeley.edu>, "David S . Miller" <davem@davemloft.net>, Richard Weinberger <richard@nod.at>, Anton Ivanov <anton.ivanov@cambridgegreys.com>, Johannes Berg <johannes@sipsolutions.net>, Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, Dave Hansen <dave.hansen@linux.intel.com>, "H . Peter Anvin" <hpa@zytor.com>, Chris Zankel <chris@zankel.net>, Max Filippov <jcmvbkbc@gmail.com>, John Stultz <john.stultz@linaro.org>, Stephen Boyd <sboyd@kernel.org>, Dinh Nguyen <dinguyen@kernel.org>, linux-arm-kernel@lists.infradead.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-riscv@lists.infradead.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, x86@kernel.org, linux-xtensa@linux-xtensa.org Subject: [PATCH v4 10/11] xtensa: use fallback for random_get_entropy() instead of zero Date: Wed, 13 Apr 2022 13:54:10 +0200 Message-Id: <20220413115411.21489-11-Jason@zx2c4.com> In-Reply-To: <20220413115411.21489-1-Jason@zx2c4.com> References: <20220413115411.21489-1-Jason@zx2c4.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220413_045611_692066_21EAD345 X-CRM114-Status: GOOD ( 16.95 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: <linux-riscv.lists.infradead.org> List-Unsubscribe: <http://lists.infradead.org/mailman/options/linux-riscv>, <mailto:linux-riscv-request@lists.infradead.org?subject=unsubscribe> List-Archive: <http://lists.infradead.org/pipermail/linux-riscv/> List-Post: <mailto:linux-riscv@lists.infradead.org> List-Help: <mailto:linux-riscv-request@lists.infradead.org?subject=help> List-Subscribe: <http://lists.infradead.org/mailman/listinfo/linux-riscv>, <mailto:linux-riscv-request@lists.infradead.org?subject=subscribe> Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" <linux-riscv-bounces@lists.infradead.org> Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org |
Series |
archs/random: fallback to best raw ktime when no cycle counter
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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 <asm-generic/timex.h> + #endif /* _XTENSA_TIMEX_H */
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 <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> --- arch/xtensa/include/asm/timex.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)