SoThOr Posted May 11, 2019 Share Posted May 11, 2019 This was spurred on from a discussion in the Clover General thread. Where there was a debate on bcdedit being able create/read/edit (U)EFI Boot entries. I didn't think it appropriate to post all this information there and somebody may want to make use of this and its likely to get lost in that massive thread. Out of curiosity I decided to see if I could create an EFI entry using bcdedit. What can I say I like a challenge. Whilst is not a documented method by Microsoft, as it turns out in a round about way it IS possible to create an EFI entry using bcdedit and these are the steps I went through to add UEFI Shell located on a USB stick to the EFI entries. Third party software is available that can create and edit UEFI entries from Windows with better support and more features. I'm just making this information available in case those options are unavailable. DISCLAIMER - This is not a supported method. Use at your own risk. I recommend backing up your BCD/Firmware variables/settings beforehand. 1) Copy {bootmgr} entry. C:\Windows\System32>bcdedit /copy {bootmgr} /d "UEFI Shell" The entry was successfully copied to {34e8383c-73a7-11e9-9cb0-94de8078a7b5}. 2) Edit the new entry using the new GUID bcdedit generated in the copy step. a) Set the device and path for UEFI shell on my USB stick. bcdedit /set {34e8383d-73a7-11e9-9cb0-94de8078a7b5} device partition=G: bcdedit /set {34e8383d-73a7-11e9-9cb0-94de8078a7b5} path \EFI\SHELL\SHELLX64.efi b) Clean up some of the stuff that was copied from {bootmgr} (optional as far as I can tell, just makes things tidier in bcdedit) Spoiler bcdedit /deletevalue {34e8383d-73a7-11e9-9cb0-94de8078a7b5} locale bcdedit /deletevalue {34e8383d-73a7-11e9-9cb0-94de8078a7b5} inherit bcdedit /deletevalue {34e8383d-73a7-11e9-9cb0-94de8078a7b5} default bcdedit /deletevalue {34e8383d-73a7-11e9-9cb0-94de8078a7b5} resumeobject bcdedit /deletevalue {34e8383d-73a7-11e9-9cb0-94de8078a7b5} displayorder bcdedit /deletevalue {34e8383d-73a7-11e9-9cb0-94de8078a7b5} toolsdisplayorder bcdedit /deletevalue {34e8383d-73a7-11e9-9cb0-94de8078a7b5} timeout 3) Put the new EFI entry first in boot order. (optional) Spoiler bcdedit /set {fwbootmgr} displayorder {34e8383d-73a7-11e9-9cb0-94de8078a7b5} /addfirst After completing the steps above, here is what "bcdedit /enum firmware" shows: Spoiler Firmware Boot Manager --------------------- identifier {fwbootmgr} displayorder {34e8383d-73a7-11e9-9cb0-94de8078a7b5} {bootmgr} {eace909f-3cb3-11e5-b87a-c28123693819} timeout 1 Windows Boot Manager -------------------- identifier {34e8383d-73a7-11e9-9cb0-94de8078a7b5} device partition=G: path \EFI\SHELL\SHELLX64.efi description UEFI Shell Windows Boot Manager -------------------- identifier {bootmgr} device partition=S: path \EFI\Microsoft\Boot\bootmgfw.efi description Windows Boot Manager locale en-US inherit {globalsettings} default {current} resumeobject {631bdfec-580c-11e8-9c1a-9d7903c42521} displayorder {current} toolsdisplayorder {memdiag} timeout 0 Firmware Application (101fffff) ------------------------------- identifier {eace909f-3cb3-11e5-b87a-c28123693819} device partition=\Device\HarddiskVolume8 path \EFI\Microsoft\Boot\bootmgfw.efi description Windows Boot Manager I shutdown my computer and when I turned my computer back on it booted up into UEFI Shell. After exiting the shell my PC went on to boot Windows. Here is the resulting dump using "bcfg boot dump -v" from that shell: Spoiler Option: 00. Variable: Boot0001 Desc - UEFI Shell DevPath - HD(1,MBR,0x00020fa6,0x3f,0x64000)/\EFI\SHELL\SHELLX64.efi Optional- Y 00000000: 57 49 4E 44 4F 57 53 00-01 00 00 00 88 00 00 00 *WINDOWS.........* 00000010: 78 00 00 00 42 00 43 00-44 00 4F 00 42 00 4A 00 *x...B.C.D.O.B.J.* 00000020: 45 00 43 00 54 00 3D 00-7B 00 33 00 34 00 65 00 *E.C.T.=.{.3.4.e.* 00000030: 38 00 33 00 38 00 33 00-64 00 2D 00 37 00 33 00 *8.3.8.3.d.-.7.3.* 00000040: 61 00 37 00 2D 00 31 00-31 00 65 00 39 00 2D 00 *a.7.-.1.1.e.9.-.* 00000050: 39 00 63 00 62 00 30 00-2D 00 39 00 34 00 64 00 *9.c.b.0.-.9.4.d.* 00000060: 65 00 38 00 30 00 37 00-38 00 61 00 37 00 62 00 *e.8.0.7.8.a.7.b.* 00000070: 35 00 7D 00 00 00 30 00-01 00 00 00 10 00 00 00 *5.}...0.........* 00000080: 04 00 00 00 7F FF 04 00- *........* Option: 01. Variable: Boot0000 Desc - Windows Boot Manager DevPath - HD(2,GPT,1aca364d-82dd-4f63-ac0e-aa9aa224e877,0xe1800,0x31800)/\EFI\Microsoft\Boot\bootmgfw.efi Optional- Y 00000000: 57 49 4E 44 4F 57 53 00-01 00 00 00 88 00 00 00 *WINDOWS.........* 00000010: 78 00 00 00 42 00 43 00-44 00 4F 00 42 00 4A 00 *x...B.C.D.O.B.J.* 00000020: 45 00 43 00 54 00 3D 00-7B 00 39 00 64 00 65 00 *E.C.T.=.{.9.d.e.* 00000030: 61 00 38 00 36 00 32 00-63 00 2D 00 35 00 63 00 *a.8.6.2.c.-.5.c.* 00000040: 64 00 64 00 2D 00 34 00-65 00 37 00 30 00 2D 00 *d.d.-.4.e.7.0.-.* 00000050: 61 00 63 00 63 00 31 00-2D 00 66 00 33 00 32 00 *a.c.c.1.-.f.3.2.* 00000060: 62 00 33 00 34 00 34 00-64 00 34 00 37 00 39 00 *b.3.4.4.d.4.7.9.* 00000070: 35 00 7D 00 00 00 30 00-01 00 00 00 10 00 00 00 *5.}...0.........* 00000080: 04 00 00 00 7F FF 04 00- *........* Option: 02. Variable: Boot0004 Desc - Windows Boot Manager DevPath - HD(2,GPT,8429c978-b940-4995-82c2-1981df946ece,0x96800,0x32000)/\EFI\Microsoft\Boot\bootmgfw.efi Optional- N You may notice that the shell shows as "Windows Boot Manager" in the bcdedit output. This I believe is because of the "WINDOWS" at the beginning of the option data that bcdedit added to the EFI Boot entry. I also believe this why bcdedit shows my Windows 8 installation as "Firmware Application" because it has no option data. I don't know how to remove this data using bcdedit nor do I know how the option data, that bcdedit adds, will affect other EFI applications. There might be a way to create the EFI entry without copying the Windows entry but if there is I'm unable to find any documentation on how one would do so. If you use the create command then it just puts it in the BCD and I'm unaware of a way to tell it to create it in EFI instead, other than by doing the above. 4 1 Link to comment Share on other sites More sharing options...
makk Posted July 14, 2023 Share Posted July 14, 2023 @SoThOr what do you mean by UEFI Shell? Are you talking about the entire OpenCore or just the Shell app? and what did it look like afterwards of copying UEFI Shell? no photos to show it Link to comment Share on other sites More sharing options...
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