[PATCH 2/2] efi_loader: remove non vital devices first

[Simon Glass]

Hi,

On Wed, 13 Nov 2024 at 05:52, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> On 11/1/24 21:29, Mark Kettenis wrote:
> >> From: Janne Grunau <j at jannau.net>
> >> Date: Thu, 31 Oct 2024 23:48:02 +0100
> >>
> >> DM_FLAG_VITAL marks devices which are essential for the operation of
> >> other devices. Removing these devices before their users can result in
> >> hangs or crashes.
> >> This potentially fixes EFI boot of Renesas rcar3 devices. Their clock
> >> devices (and with this series the dart iommu) are the only devices
> >> markes as vital.
> >> The arm boot code already handles devioce removal in this way.
> >
> > There is a typo in that last sentence of the commit message (devioce).
> > Otherwise:
> >
> >> Signed-off-by: Janne Grunau <j at jannau.net>
> >
> > Reviewed-by: Mark Kettenis <kettenis at openbsd.org>
> >
> >> ---
> >>   lib/efi_loader/efi_boottime.c | 1 +
> >>   1 file changed, 1 insertion(+)
> >>
> >> diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
> >> index 4f52284b4c653c252b0ed6c0c87da8901448d4b4..7db3c95782970f8c06a970a8ee86b1804cd848b6 100644
> >> --- a/lib/efi_loader/efi_boottime.c
> >> +++ b/lib/efi_loader/efi_boottime.c
> >> @@ -2234,6 +2234,7 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
> >>              if (IS_ENABLED(CONFIG_USB_DEVICE))
> >>                      udc_disconnect();
> >>              board_quiesce_devices();
> >> +            dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL | DM_REMOVE_NON_VITAL);
> >>              dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);
>
> Simon's patch 6224dc9ba428 ("arm: Remove vital devices last") addressed
> the same issue for bootm on arm. But what about about other architectures?
>
> This logic should be moved to drivers/core/root.c instead of replicating
> code.

We could have a common helper, but it should not be in driver/core as
this ordering is more of a policy decision. Unless we can add a
parameter telling dm exactly what to do...

BTW, Heinrich, this behaviour is exactly what my bootflow_efi() test
was supposed to check. But since it doesn't have the
exit-boot-services piece at your request...

Regards,
Simon