Re: [PATCH] efi: avoid error message when booting under Xen

On Fri, 10 Jul 2020 at 13:17, Bartlomiej Zolnierkiewicz
[off-list ref] wrote:

[ added EFI Maintainer & ML to Cc: ]

Hi,

On 7/9/20 11:17 AM, Jürgen Groß wrote:

quoted

On 28.06.20 10:50, Jürgen Groß wrote:

quoted

Ping?

On 10.06.20 16:10, Juergen Gross wrote:

quoted

efifb_probe() will issue an error message in case the kernel is booted
as Xen dom0 from UEFI as EFI_MEMMAP won't be set in this case. Avoid
that message by calling efi_mem_desc_lookup() only if EFI_PARAVIRT
isn't set.

Why not test for EFI_MEMMAP instead of EFI_BOOT?

quoted

quoted

quoted

Fixes: 38ac0287b7f4 ("fbdev/efifb: Honour UEFI memory map attributes when mapping the FB")
Signed-off-by: Juergen Gross <jgross@suse.com>
---
  drivers/video/fbdev/efifb.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
index 65491ae74808..f5eccd1373e9 100644
--- a/drivers/video/fbdev/efifb.c
+++ b/drivers/video/fbdev/efifb.c

@@ -453,7 +453,7 @@ static int efifb_probe(struct platform_device *dev)
      info->apertures->ranges[0].base = efifb_fix.smem_start;
      info->apertures->ranges[0].size = size_remap;
-    if (efi_enabled(EFI_BOOT) &&
+    if (efi_enabled(EFI_BOOT) && !efi_enabled(EFI_PARAVIRT) &&
          !efi_mem_desc_lookup(efifb_fix.smem_start, &md)) {
          if ((efifb_fix.smem_start + efifb_fix.smem_len) >
              (md.phys_addr + (md.num_pages << EFI_PAGE_SHIFT))) {

In case I see no reaction from the maintainer for another week I'll take
this patch through the Xen tree.

From fbdev POV this change looks fine to me and I'm OK with merging it
through Xen or EFI tree:

Acked-by: Bartlomiej Zolnierkiewicz <redacted>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics