On Monday, June 25, 2018 11:58:11 AM Ard Biesheuvel wrote: > ,On 22 June 2018 at 09:52, Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> wrote: > > If the framebuffer address provided by the Graphics Output Protocol > > (GOP) is covered by the UEFI memory map, it will tell us which memory > > attributes are permitted when mapping this region. In some cases, > > (KVM guest on ARM), violating this will result in loss of coherency, > > which means that updates sent to the framebuffer by the guest will > > not be observeable by the host, and the emulated display simply does > > not work. > > > > So if the memory map contains such a description, take the attributes > > field into account, and add support for creating WT or WB mappings of > > the framebuffer region. > > > > Cc: linux-fbdev@xxxxxxxxxxxxxxx > > Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> > > Cc: Peter Jones <pjones@xxxxxxxxxx> > > Tested-by: Laszlo Ersek <lersek@xxxxxxxxxx> > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> > > Bartlomiej, do you have any comments on this patch? If not, I would > like to queue it in the efi tree. > > @@ -164,6 +168,8 @@ static int efifb_probe(struct platform_device *dev) > > unsigned int size_remap; > > unsigned int size_total; > > char *option = NULL; > > + efi_memory_desc_t md; > > + > > minor nit: redundant newline the rest looks fine to me Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html