From patchwork Mon Nov 11 18:29:33 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 11237451 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A511C16B1 for ; Mon, 11 Nov 2019 18:58:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 832C621925 for ; Mon, 11 Nov 2019 18:58:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573498700; bh=c73pM0vMfB+nZzLpqXcyf8WgkHue4kWXssjUlDgME5o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=N5n2B3VRkYgNfL3+NCMQgoBfpAChrW+qLUjimT0qsmCUixU1JaUpNSqAmEZPorchB 7FdpOld/eS9IJDQ1sSSV2YhYz/+rrZAKnEMPQbAHOR1HwdXUmq8my6V6C6ZNf3GE6d 6uMlzpKtShc/aZvlGmhUbwluYAGfnYmqIOuESXu0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730693AbfKKS6P (ORCPT ); Mon, 11 Nov 2019 13:58:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:58642 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730937AbfKKS6O (ORCPT ); Mon, 11 Nov 2019 13:58:14 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4AA3521655; Mon, 11 Nov 2019 18:58:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573498693; bh=c73pM0vMfB+nZzLpqXcyf8WgkHue4kWXssjUlDgME5o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pyWXGoqv917xMNMv9FPxldo8lUrIwkUUBU8lwct6VhjC3sAidO54rBIghe+1P95bq 8xab4n12FSl2aI/gDoHEwVr6Buk+NPxoIhh1qpX/Ag7Nv3Wr1WGQV1tzM0CC+RbmP7 7+MSiHS8e/HPZGe9sGhego8IevAdwmj5IqqfDmlM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Huacai Chen , Thomas Gleixner , Andy Lutomirski , Vincenzo Frascino , Arnd Bergmann , Paul Burton , linux-mips@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sasha Levin Subject: [PATCH 5.3 191/193] timekeeping/vsyscall: Update VDSO data unconditionally Date: Mon, 11 Nov 2019 19:29:33 +0100 Message-Id: <20191111181515.176484931@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191111181459.850623879@linuxfoundation.org> References: <20191111181459.850623879@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Huacai Chen [ Upstream commit 52338415cf4d4064ae6b8dd972dadbda841da4fa ] The update of the VDSO data is depending on __arch_use_vsyscall() returning True. This is a leftover from the attempt to map the features of various architectures 1:1 into generic code. The usage of __arch_use_vsyscall() in the actual vsyscall implementations got dropped and replaced by the requirement for the architecture code to return U64_MAX if the global clocksource is not usable in the VDSO. But the __arch_use_vsyscall() check in the update code stayed which causes the VDSO data to be stale or invalid when an architecture actually implements that function and returns False when the current clocksource is not usable in the VDSO. As a consequence the VDSO implementations of clock_getres(), time(), clock_gettime(CLOCK_.*_COARSE) operate on invalid data and return bogus information. Remove the __arch_use_vsyscall() check from the VDSO update function and update the VDSO data unconditionally. [ tglx: Massaged changelog and removed the now useless implementations in asm-generic/ARM64/MIPS ] Fixes: 44f57d788e7deecb50 ("timekeeping: Provide a generic update_vsyscall() implementation") Signed-off-by: Huacai Chen Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Vincenzo Frascino Cc: Arnd Bergmann Cc: Paul Burton Cc: linux-mips@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1571887709-11447-1-git-send-email-chenhc@lemote.com Signed-off-by: Sasha Levin --- arch/arm64/include/asm/vdso/vsyscall.h | 7 ------- include/asm-generic/vdso/vsyscall.h | 7 ------- kernel/time/vsyscall.c | 9 +++------ 3 files changed, 3 insertions(+), 20 deletions(-) diff --git a/arch/arm64/include/asm/vdso/vsyscall.h b/arch/arm64/include/asm/vdso/vsyscall.h index 0c731bfc7c8c7..0c20a7c1bee50 100644 --- a/arch/arm64/include/asm/vdso/vsyscall.h +++ b/arch/arm64/include/asm/vdso/vsyscall.h @@ -30,13 +30,6 @@ int __arm64_get_clock_mode(struct timekeeper *tk) } #define __arch_get_clock_mode __arm64_get_clock_mode -static __always_inline -int __arm64_use_vsyscall(struct vdso_data *vdata) -{ - return !vdata[CS_HRES_COARSE].clock_mode; -} -#define __arch_use_vsyscall __arm64_use_vsyscall - static __always_inline void __arm64_update_vsyscall(struct vdso_data *vdata, struct timekeeper *tk) { diff --git a/include/asm-generic/vdso/vsyscall.h b/include/asm-generic/vdso/vsyscall.h index e94b19782c92f..ce41032086193 100644 --- a/include/asm-generic/vdso/vsyscall.h +++ b/include/asm-generic/vdso/vsyscall.h @@ -25,13 +25,6 @@ static __always_inline int __arch_get_clock_mode(struct timekeeper *tk) } #endif /* __arch_get_clock_mode */ -#ifndef __arch_use_vsyscall -static __always_inline int __arch_use_vsyscall(struct vdso_data *vdata) -{ - return 1; -} -#endif /* __arch_use_vsyscall */ - #ifndef __arch_update_vsyscall static __always_inline void __arch_update_vsyscall(struct vdso_data *vdata, struct timekeeper *tk) diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c index 4bc37ac3bb052..5ee0f77094107 100644 --- a/kernel/time/vsyscall.c +++ b/kernel/time/vsyscall.c @@ -110,8 +110,7 @@ void update_vsyscall(struct timekeeper *tk) nsec = nsec + tk->wall_to_monotonic.tv_nsec; vdso_ts->sec += __iter_div_u64_rem(nsec, NSEC_PER_SEC, &vdso_ts->nsec); - if (__arch_use_vsyscall(vdata)) - update_vdso_data(vdata, tk); + update_vdso_data(vdata, tk); __arch_update_vsyscall(vdata, tk); @@ -124,10 +123,8 @@ void update_vsyscall_tz(void) { struct vdso_data *vdata = __arch_get_k_vdso_data(); - if (__arch_use_vsyscall(vdata)) { - vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest; - vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime; - } + vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest; + vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime; __arch_sync_vdso_data(vdata); }