From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753595AbbCFNco (ORCPT ); Fri, 6 Mar 2015 08:32:44 -0500 Received: from mailout2.samsung.com ([203.254.224.25]:11944 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753449AbbCFNcl (ORCPT ); Fri, 6 Mar 2015 08:32:41 -0500 MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 X-AuditID: cbfee691-f79b86d000004a5a-51-54f9ac761bae Content-transfer-encoding: 8BIT Message-id: <54F9AC76.1000305@samsung.com> Date: Fri, 06 Mar 2015 22:32:38 +0900 From: Inki Dae User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130803 Thunderbird/17.0.8 To: Javier Martinez Canillas Cc: Marek Szyprowski , Kevin Hilman , Kukjin Kim , Olof Johansson , Krzysztof Kozlowski , Andreas Faerber , linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, tyler.baker@linaro.org, Andrzej Hajda , Inki Dae , Gustavo Padovan Subject: Re: [PATCH 1/1] ARM: exynos_defconfig: Disable IOMMU support References: <1424173109-30347-1-git-send-email-javier.martinez@collabora.co.uk> <7hioehu8cn.fsf@linaro.org> <54F6C746.606@samsung.com> <54F6DD79.9070009@collabora.co.uk> In-reply-to: <54F6DD79.9070009@collabora.co.uk> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrLIsWRmVeSWpSXmKPExsWyRsSkSLdszc8QgwVnJSxurTvHatG8qdji addFZotPq1vZLY7+LrB4/cLQov/xa2aLp5sfM1lc3jWHzWLG+X1MFmuP3GW3OHX9M5vFxx33 WBx4Pf4+v87isXPWXXaPTas62TzuXNvD5nHlRBOrR9+WVYwem09Xe3zeJBfAEcVlk5Kak1mW WqRvl8CVcXfSZ5aCH9oVsw++ZWtgXKzSxcjJISFgIrHrww4mCFtM4sK99WxdjFwcQgJLGSWW 33/KDFM0e9lZdojEdEaJyR9usoMkeAUEJX5MvsfSxcjBwSwgL3HkUjZImFlAXWLSvEXMEPWv GCVWfT7PCFGvJTF7wWEWEJtFQFVi6pYesDgbkD1xxX02EFtUIEzixatdYItFBOwkbqx+CDaI WeAQs8SF5RCLhQVcJa5c+sUCsWEto8SpNX/AOjgF9CVW/tzJBJKQEOjlkJi44yI7xDoBiW+T D4GdKiEgK7HpANRrkhIHV9xgmcAoNgvJQ7MQHpqF5KEFjMyrGEVTC5ILipPSi0z1ihNzi0vz 0vWS83M3MQJj+fS/ZxN3MN4/YH2IUYCDUYmHV0PwZ4gQa2JZcWXuIUZToCMmMkuJJucDE0Ze SbyhsZmRhamJqbGRuaWZkjivjvTPYCGB9MSS1OzU1ILUovii0pzU4kOMTBycUg2McqLrbv9k 2pjGmvn82KcTDcvX/FKpVm01YDHPqIuXCpv+S0GtZZX8zcLIfZzCj9RkNHWkqvhYv69etnyn g/1fL6X9T2dw75RXljmR6yrkE7X++zbPX1u6nlxP/XxIRrjwjeHrC9KrIr77Mt/7or3oTMiV N4rP6+xsu8pMQv+fPnHj6ZonG3ZcVGIpzkg01GIuKk4EAO4norXgAgAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprOKsWRmVeSWpSXmKPExsVy+t9jQd2yNT9DDO7N5LO4te4cq0XzpmKL p10XmS0+rW5ltzj6u8Di9QtDi/7Hr5ktnm5+zGRxedccNosZ5/cxWaw9cpfd4tT1z2wWH3fc Y3Hg9fj7/DqLx85Zd9k9Nq3qZPO4c20Pm8eVE02sHn1bVjF6bD5d7fF5k1wAR1QDo01GamJK apFCal5yfkpmXrqtkndwvHO8qZmBoa6hpYW5kkJeYm6qrZKLT4CuW2YO0MFKCmWJOaVAoYDE 4mIlfTtME0JD3HQtYBojdH1DguB6jAzQQMIaxoy7kz6zFPzQrph98C1bA+NilS5GTg4JAROJ 2cvOskPYYhIX7q1n62Lk4hASmM4oMfnDTbAEr4CgxI/J91i6GDk4mAXkJY5cygYJMwuoS0ya t4gZov4Vo8Sqz+cZIeq1JGYvOMwCYrMIqEpM3dIDFmcDsieuuM8GYosKhEm8eLWLGcQWEbCT uLH6IdggZoFDzBIXlkMsFhZwlbhy6RcLxIa1jBKn1vwB6+AU0JdY+XMn0wRGgVlIDpyFcOAs JAcuYGRexSiaWpBcUJyUnmuoV5yYW1yal66XnJ+7iRGcKJ5J7WBc2WBxiFGAg1GJh7dB+GeI EGtiWXFl7iFGCQ5mJRFezuVAId6UxMqq1KL8+KLSnNTiQ4ymQO9NZJYSTc4HJrG8knhDYxMz I0sjc0MLI2NzJXFeJfu2ECGB9MSS1OzU1ILUIpg+Jg5OqQbGFXz8N3cY123K3qhaz2/I+uLe Laus8+pr/RhV38k0iO6raNafNLF04ZOTF5f7FIm9bPVKyPzEsWWdoVSRDJu63w5X6RktdwzP vwplvXxl5aMMgUsHgvfMrTUKinsXYBIk9nKzxPeJMv8y/kawFz2UbH4kdIHRZi3zBwnh3WnS jLuF2M7/idqkxFKckWioxVxUnAgA3GwgqyoDAAA= DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, On 2015년 03월 04일 19:24, Javier Martinez Canillas wrote: > +Gustavo which has been looking at the issues > > Hello, > > On 03/04/2015 09:50 AM, Marek Szyprowski wrote: >> Hello, >> >> On 2015-03-03 21:36, Kevin Hilman wrote: >>> Javier Martinez Canillas writes: >>> >>>> Enabling Exynos DRM IOMMU support for Exynos is currently broken and >>>> causes a BUG on exynos-iommu driver. This was not an issue since the >>>> options was disabled in exynos_defconfig but after commit 8dcc14f82f06 >>>> ("drm/exynos: IOMMU support should not be selectable by user"), it is >>>> selected if EXYNOS_IOMMU is enabled which is in exynos_defconfig. >>>> >>>> So a kernel built using exynos_defconfig after the mentioned commit >>>> fails to boot [0]. Disable IOMMU support in Exynos defconfig until >>>> things get sorted out. >>> So some other exynos boards started failing in next-20150303[1], and >>> appear are DRM failures. >>> >>> Interestingly, (re)enabling CONFIG_EXYNOS_IOMMU for these cause things to >>> work again. Even more intersting, with IOMMU enabled, peach-pi is >>> > > I built both 4.0-rc2 and linux-next (tag next-20150303) with and without > CONFIG_EXYNOS_IOMMU and boot tested on Snow, Peach Pit and Pi. > > We still don't have a Peach Pit hooked in LAVA so I tested it locally > and pasted the boot logs. > > 4.0-rc2 (which has CONFIG_EXYNOS_IOMMU enabled) > ----------------------------------------------- > > * Snow: NULL pointer dereference at fimd_wait_for_vblank [0] > > * Peach Pi: kernel BUG at drivers/iommu/exynos-iommu.c:481 [1] > > * Peach Pit: NULL pointer dereference at fimd_wait_for_vblank [2] > > 4.0-rc2 + CONFIG_EXYNOS_IOMMU disabled > -------------------------------------- > > * Snow: NULL pointer dereference at exynos_plane_destroy [3] > > * Peach Pi: no error, kernel booted successfully [4] > > * Peach Pit: NULL pointer dereference at exynos_plane_destroy [5] > > next-20150303 (which has CONFIG_EXYNOS_IOMMU disabled) > ----------------------------------------------------- > > * Snow: no error, kernel booted successfully [6] > * Peach Pi: no error, kernel booted successfully [7] > * Peach Pit: no error, kernel booted successfully [8] > > next-20150303 + CONFIG_EXYNOS_IOMMU (re)enabled > ----------------------------------------------- > > Snow: no error, kernel booted successfully [9] > Peach Pi: no error, kernel booted successfully [10] > Peach Pit: no error, kernel booted successfully [11] > > Is interesting that the only Exynos5 machines that failed to boot in > next-20150303 were exynos5250-arndale and exynos5422-odroidxu3 [12]. > > Also, only the exynos5250-arndale failed to boot with next-20150304 [13] > while exynos5422-odroidxu3 booted successfully and there were no changes > for the exynos drm driver between next-20150303 and next-20150304. > > Another interesting data point is that the error in next-20150303 for > these 2 boards was the NULL pointer dereference in exynos_plane_destroy > that I got with 4.0-rc2 (when IOMMU is disabled) in Snow and Peach Pit. I think the NULL pointer dereference issue may be fixed with below patch I merged to exynos-drm-fixes just a while ago, https://lkml.org/lkml/2015/2/17/434 Could you test it with this patch again? Thanks, Inki Dae > > So it appears the error is not consistent and may be a race condition. > >>> I'm starting to think it's the DRM driver that needs to be disabled >>> until it actually gets some testing, rathre than disabling IOMMU. >> > > It's true that there are a lot of issues with the Exynos DRM driver > but OTOH those are exposed because the config is enabled by default. > > My fear is that if we disable the driver, it could silently break > and be noticed much later when a user enables the option. > >> Well, this only shows that broken patch has been merged to exynos-drm-next >> kernel tree. I think that we should keep Exynos DRM enabled and give Exynos >> DRM developers a chance to fix their stuff and then test their stuff. >> > > Agree, hopefully all these issues are sorted out during the -rc cycle but > if not then I think we would have to disable the driver as Kevin suggests. > > Another thing that may be useful to detect these issues early is to have > exynos-drm-next be pulled by linux-next since otherwise the integration > is not tested until the changes are picked by the DRM maintainer. > >> Best regards >> > > Best regards, > Javier > > [0]: https://lava.collabora.co.uk/scheduler/job/8559/log_file > [1]: https://lava.collabora.co.uk/scheduler/job/8558/log_file > [2]: http://hastebin.com/gupoworepa.xml > [3]: https://lava.collabora.co.uk/scheduler/job/8560/log_file > [4]: https://lava.collabora.co.uk/scheduler/job/8566/log_file > [5]: http://hastebin.com/ziyiruretu.xml > [6]: https://lava.collabora.co.uk/scheduler/job/8570/log_file > [7]: https://lava.collabora.co.uk/scheduler/job/8571/log_file > [8]: http://hastebin.com/felopehimi.vhdl > [9]: https://lava.collabora.co.uk/scheduler/job/8572/log_file > [10]: https://lava.collabora.co.uk/scheduler/job/8573/log_file > [11]: http://hastebin.com/kazupucufu.vhdl > [12]: http://kernelci.org/boot/?next-20150303&fail > [13]: http://kernelci.org/boot/?next-20150304&fail > -- > To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >