From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH v2 3/4] input: Deprecate real timestamps beyond year 2106 Date: Fri, 28 Oct 2016 17:45:20 +0200 Message-ID: <1960434.J8MW3Y2VCi@wuerfel> References: <1476761253-13450-1-git-send-email-deepa.kernel@gmail.com> <5347568.3SpFZiqxSr@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Deepa Dinamani Cc: Dmitry Torokhov , linux-input@vger.kernel.org, Linux Kernel Mailing List , y2038 Mailman List List-Id: linux-input@vger.kernel.org On Friday, October 28, 2016 8:19:46 AM CEST Deepa Dinamani wrote: > On Fri, Oct 28, 2016 at 5:43 AM, Arnd Bergmann wrote: > > On Monday, October 17, 2016 8:27:32 PM CEST Deepa Dinamani wrote: > >> @@ -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). ARnd