On Friday, July 27, 2018 09:49:41 AM Jia-Ju Bai wrote: > > On 2018/7/26 22:34, Bartlomiej Zolnierkiewicz wrote: > > On Thursday, July 26, 2018 10:17:44 PM bai wrote: > >> In Linux-4.16, drivers/video/fbdev/broadsheetfb.c, > >> > >> 158. static void broadsheet_mmio_send_cmdargs(...) { > >> ...... > >> 163. par->board->mmio_write(...); > >> ...... > >> 166. par->board->mmio_write(...); > >> 167. } > >> > >> For x86 kernel configuration, I find that there is no assignment of the > >> function pointer ".mmio_write" in the kernel code. > >> So calling the function pointer in lines 163 and 166 may cause a null > >> pointer dereference. > >> > >> In this file, there are many calls to this function pointer... > > This is a platform driver and it won't be used on x86 (actually it is > > used only by single ARM PXA board). The dependency for FB_BROADSHEET > > in Kconfig file could be improved to i.e. > > > > depends on FB && (ARCH_PXA || COMPILE_TEST) > > > > but there is no bug there. > > Thanks for the reply :) > So I want to submit a patch of updating Kconfig in > drivers/video/fbdev/Kconfig: > > config FB_BROADSHEET > tristate "E-Ink Broadsheet/Epson S1D13521 controller support" > - depends on FB > + depends on FB && (ARCH_PXA || COMPILE_TEST) > select FB_SYS_FILLRECT > select FB_SYS_COPYAREA > select FB_SYS_IMAGEBLIT > select FB_SYS_FOPS > select FB_DEFERRED_IO > > > Do you think it is okay? Please read Documentation/process/submitting-patches.rst. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel