From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [PATCH v2 0/2] NVIDIA Tegra I2C synchronization correction Date: Wed, 15 Apr 2020 17:14:39 +0300 Message-ID: <87f18a67-5aec-b5df-9d8f-341f03ff3a72@gmail.com> References: <20200324191217.1829-1-digetx@gmail.com> <20200415114536.GB910@ninjato> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200415114536.GB910@ninjato> Content-Language: en-US Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Wolfram Sang Cc: Thierry Reding , Jonathan Hunter , Laxman Dewangan , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org 15.04.2020 14:45, Wolfram Sang пишет: > On Tue, Mar 24, 2020 at 10:12:15PM +0300, Dmitry Osipenko wrote: >> Hello, >> >> Recently I found a way to reliably reproduce I2C timeouts that happen due >> to improper synchronizations made by the I2C driver. It's quite easy to >> reproduce the problem when memory is running on a lower freq + there is >> some memory activity + CPU could get busy for a significant time. This >> is the case when KASAN is enabled and CPU is busy while accessing FS via >> NFS. This small series addresses the found problems. >> >> Changelog: >> >> v2: - The "Better handle case where CPU0 is busy for a long time" patch >> now preserves the old behavior where completion is checked after >> disabling the interrupt, preventing potential race-condition of >> the completion awaiting vs interrupt syncing. >> >> Dmitry Osipenko (2): >> i2c: tegra: Better handle case where CPU0 is busy for a long time >> i2c: tegra: Synchronize DMA before termination > > Patches look good to me. I tend to apply them to for-current instead of > for-next because they are fixing issues. Even a stable tag? > Thank you, yes it should be good to apply this series to 5.7 because the Tegra APBDMA driver dependency-patches are already in 5.7. The stable tag shouldn't be needed since this is not a critical bug fix and the DMA driver patches are not going into stable. This series should be more actual for the upcoming devices, which should be upstreamed in 5.8+.