Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761926AbcJ1Vji (ORCPT ); Fri, 28 Oct 2016 17:39:38 -0400 Received: from mail-oi0-f65.google.com ([209.85.218.65]:33828 "EHLO mail-oi0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755971AbcJ1Vjg (ORCPT ); Fri, 28 Oct 2016 17:39:36 -0400 MIME-Version: 1.0 In-Reply-To: <1960434.J8MW3Y2VCi@wuerfel> References: <1476761253-13450-1-git-send-email-deepa.kernel@gmail.com> <5347568.3SpFZiqxSr@wuerfel> <1960434.J8MW3Y2VCi@wuerfel> From: Deepa Dinamani Date: Fri, 28 Oct 2016 14:39:35 -0700 Message-ID: Subject: Re: [PATCH v2 3/4] input: Deprecate real timestamps beyond year 2106 To: Arnd Bergmann Cc: Dmitry Torokhov , linux-input@vger.kernel.org, Linux Kernel Mailing List , y2038 Mailman List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1551 Lines: 43 >> >> @@ -55,24 +60,24 @@ struct ff_effect_compat { >> >> >> >> static inline size_t input_event_size(void) >> >> { >> >> - return (in_compat_syscall() && !COMPAT_USE_64BIT_TIME) ? >> >> - sizeof(struct input_event_compat) : sizeof(struct input_event); >> >> + return in_compat_syscall() ? sizeof(struct raw_input_event_compat) : >> >> + sizeof(struct raw_input_event); >> >> } >> > >> > I think the COMPAT_USE_64BIT_TIME check has to stay here, >> > it's needed for x32 mode on x86-64. >> >> There is no time_t anymore in the raw_input_event structure. >> The struct uses __kernel_ulong_t type. >> This should take care of x32 support. > > I don't think it does. > >> From this cover letter: >> https://www.spinics.net/lists/linux-arch/msg16356.html >> >> I see that that the __kernel types were introduced to address the ABI >> issues for x32. > > This is a variation of the problem we are trying to solve for > the other architectures in your patch set: > > On x32, the kernel uses produces a structure with the 64-bit > layout, using __u64 tv_sec, to match the current user space > that has 64-bit __kernel_ulong_t and 64-bit time_t, but > in_compat_syscall() also returns 'true' here, as this is > mostly a 32-bit ABI (time_t being one of the exceptions). Yes, I missed this. in_compat_syscall() is true for x32, this would mean we end up here even if it is a x32 syscall. But, wouldn't it be better to use in_x32_syscall() here since there is no timeval any more? Thanks, Deepa