On 29 April 2016 at 16:39, Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx> wrote: > On Fri, 29 Apr, at 11:34:45AM, Stefano Stabellini wrote: >> On Fri, 29 Apr 2016, Ingo Molnar wrote: >> > Also, it would be nice to have all things EFI in a single tree, the conflicts are >> > going to be painful! There's very little reason not to carry this kind of commit: >> > >> > arch/arm/xen/enlighten.c | 6 +++++ >> > drivers/firmware/efi/arm-runtime.c | 17 +++++++++----- >> > drivers/firmware/efi/efi.c | 45 ++++++++++++++++++++++++++++++++------ >> > 3 files changed, 56 insertions(+), 12 deletions(-) >> > >> > in the EFI tree. >> >> That's true. I'll drop this commit from xentip and let Matt pick it up >> or request changes as he sees fit. > > One small change I think would be sensible to make is to expand > EFI_PARAVIRT into a few more bits to clearly indicate the quirks on > Xen, and in the process, to delete EFI_PARAVIRT. > > That should address Ingo's major concern, and also make it much easier > to rework the code in a piecemeal fashion. > > Could somebody enumerate the things that make Xen (dom0) different on > arm* compared with bare metal EFI boot? The list I made for x86 was, > > 1. Has no EFI memory map > 2. Runtime regions do not need to be mapped > 3. Cannot call SetVirtualAddressMap() > 4. /sys/firmware/efi/fw_vendor is invisible > > The first maps to not setting EFI_MEMMAP, the second to not setting > EFI_RUNTIME. If we add EFI_ALREADY_VIRTUAL and EFI_FW_VENDOR_INVISIBLE > to efi.flags that should cover everything on x86. Does arm* require > anything else? I already proposed when this patch was first under review to make the arm_enable_runtime_services() function bail early without error if the EFI_RUNTIME_SERVICES flag is already set, and the xen code could set that bit as well when it installs its paravirtualized alternatives. I don't remember exactly why that was shot down, though, but I think it is the only reason this code introduces references to EFI_PARAVIRT in the first place. -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
