From mboxrd@z Thu Jan 1 00:00:00 1970 From: Emil Medve Subject: Re: [PATCH v2 01/26] iommu/fsl: Sprinkle some __init* annotations Date: Wed, 11 Feb 2015 05:07:06 -0600 Message-ID: <54DB37DA.2040500@Freescale.com> References: <1422455698-3074-1-git-send-email-Emilian.Medve@Freescale.com> <1422455698-3074-2-git-send-email-Emilian.Medve@Freescale.com> <54D92ABC.3030802@Freescale.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Sethi Varun-B16395 , "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , "joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org" , "jroedel-l3A5Bk7waGM@public.gmane.org" List-Id: iommu@lists.linux-foundation.org Hello Varun, On 02/09/2015 08:26 PM, Sethi Varun-B16395 wrote: > Hi Emil, > > >> -----Original Message----- >> From: Emil Medve [mailto:Emilian.Medve-eDlz3WWmN0ll57MIdRCFDg@public.gmane.org] >> Sent: Tuesday, February 10, 2015 3:17 AM >> To: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org; joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org; jroedel-l3A5Bk7waGM@public.gmane.org; >> Sethi Varun-B16395 >> Subject: Re: [PATCH v2 01/26] iommu/fsl: Sprinkle some __init* annotations >> >> Hello Joerg, >> >> >> On 01/28/2015 08:34 AM, Emil Medve wrote: >>> Signed-off-by: Emil Medve >>> --- >>> drivers/iommu/fsl_pamu.c | 12 ++++++------ >>> drivers/iommu/fsl_pamu_domain.c | 2 +- >>> 2 files changed, 7 insertions(+), 7 deletions(-) >> >> Please don't apply this patch as it's wrong. It's based on >> https://git.kernel.org/cgit/linux/kernel/git/joro/iommu.git/commit/?h=ppc/ >> pamu&id=0f1fb99b62ce226f8d818852f812c5d79071ce58 >> which is wrong as well and its causing semi-random crashes upon more >> extensive testing. I will follow-up with details shortly > > Are you seeing a crash with > https://git.kernel.org/cgit/linux/kernel/git/joro/iommu.git/commit/?h=ppc/pamu&id=0f1fb99b62ce226f8d818852f812c5d79071ce58 > ? At, what point do you see crashes? platform_driver.device_driver gets added to a (platform) bus klist of drivers. (There are also a handful of other pointers that get set to fsl_of_pamu_driver) Once fsl_of_pamu_driver gets released that klist becomes "corrupted" and, depending on how said memory gets re-used, traversing it for any reason will end up into a crash Anyway, I identified easier ways to produce kernel crashes related to the PAMU driver via sysfs (with or without my __init* annotation patches). For example a "unbind, bind" sequence will cause a crash with the driver as is in v3.19 BTW, why is the PAMU an "early" driver? I'll send out some patches to properly fix all these __init* annotations Cheers,