From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lauri Hintsala Date: Fri, 04 Jan 2013 07:08:12 +0000 Subject: Re: [BUGFIX PATCH] video: mxsfb: fix crash when unblanking the display Message-Id: <50E67FDC.3000905@bluegiga.com> List-Id: References: <1353588555-13168-1-git-send-email-LW@KARO-electronics.de> <20663.19785.221750.909491@ipc1.ka-ro> In-Reply-To: <20663.19785.221750.909491@ipc1.ka-ro> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: linux-arm-kernel@lists.infradead.org On 11/29/2012 01:55 PM, Lothar Waßmann wrote: > Hi, > > adding Juergen Beisert as the driver's author to the recipient list. > > Lothar Waßmann writes: >> The VDCTRL4 register does not provide the MXS SET/CLR/TOGGLE feature. >> The write in mxsfb_disable_controller() sets the data_cnt for the LCD >> DMA to 0 which obviously means the max. count for the LCD DMA and >> leads to overwriting arbitrary memory when the display is unblanked. >> >> Note: I already sent this patch in December 2011 but noone picked it up obviously. >> >> Signed-off-by: Lothar Waßmann Tested-by: Lauri Hintsala This fixes the CPU freezing. I really recommend to apply this patch into mainline soon because unblanking freezes the whole system!!! Default value of consoleblank parameter is 600 seconds and the whole system crashes every time when framebuffer console is activated after that timeout. I wonder why this issue is still open in mainline kernel. Should this patch be added into stable versions too? Best Regards, Lauri Hintsala From mboxrd@z Thu Jan 1 00:00:00 1970 From: lauri.hintsala@bluegiga.com (Lauri Hintsala) Date: Fri, 04 Jan 2013 09:08:12 +0200 Subject: [BUGFIX PATCH] video: mxsfb: fix crash when unblanking the display In-Reply-To: <20663.19785.221750.909491@ipc1.ka-ro> References: <1353588555-13168-1-git-send-email-LW@KARO-electronics.de> <20663.19785.221750.909491@ipc1.ka-ro> Message-ID: <50E67FDC.3000905@bluegiga.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 11/29/2012 01:55 PM, Lothar Wa?mann wrote: > Hi, > > adding Juergen Beisert as the driver's author to the recipient list. > > Lothar Wa?mann writes: >> The VDCTRL4 register does not provide the MXS SET/CLR/TOGGLE feature. >> The write in mxsfb_disable_controller() sets the data_cnt for the LCD >> DMA to 0 which obviously means the max. count for the LCD DMA and >> leads to overwriting arbitrary memory when the display is unblanked. >> >> Note: I already sent this patch in December 2011 but noone picked it up obviously. >> >> Signed-off-by: Lothar Wa?mann Tested-by: Lauri Hintsala This fixes the CPU freezing. I really recommend to apply this patch into mainline soon because unblanking freezes the whole system!!! Default value of consoleblank parameter is 600 seconds and the whole system crashes every time when framebuffer console is activated after that timeout. I wonder why this issue is still open in mainline kernel. Should this patch be added into stable versions too? Best Regards, Lauri Hintsala