Julian Andres Klode <julian.kl...@canonical.com> writes: > On Thu, Apr 25, 2024 at 06:30:52PM +0100, Alex Bennée wrote: >> >> Continuing to debug on QEMU it seems there is an incompatibility with >> the images and the peloader (which overrides the normal efi loader): >> >> Thread 1 hit Breakpoint 3.2, grub_load_normal_mode () at >> ../../../grub-core/kern/main.c:241 >> 241 in ../../../grub-core/kern/main.c >> >> >> (grub gdb) hbreak do_load_image >> >> >> Hardware assisted breakpoint 4 at 0x23bdf0e00: do_load_image. (2 >> locations) >> >> (grub gdb) c >> >> >> Continuing. >> >> >> add symbol table from file "bli.module" at >> >> >> .text_addr = 0x23ba772e0 >> >> >> .bss_addr = 0x0 >> >> >> .module_license_addr = 0x23ba7764a >> .data_addr = 0x0 >> >> >> .rodata.str1.1_addr = 0x23ba77560 >> >> >> .rodata_addr = 0x23ba77550 >> >> >> add symbol table from file "xen_boot.module" at >> >> >> .text_addr = 0x23bcef3c0 >> >> >> .bss_addr = 0x23bcf0370 >> >> >> .module_license_addr = 0x23bcf035e >> >> .data_addr = 0x0 >> >> .rodata.str1.1_addr = 0x23bcefff8 >> >> Thread 1 hit Breakpoint 4.1, do_load_image (boot_policy=0 '\000', >> parent_image_handle=0x23e889f18, file_path=0x237d1bce0, >> source_buffer=0x239f00000, source_size=1081352, >> image_handle=0x4766c498) at ../../../grub-core/loader/efi/peimage.c:745 >> warning: 745 ../../../grub-core/loader/efi/peimage.c: No such file or >> directory >> (grub gdb) hbreak grub_error >> Hardware assisted breakpoint 5 at 0x6db0: grub_error. (2 locations) >> (grub gdb) c >> Continuing. >> >> Thread 1 hit Breakpoint 4.2, 0x000000023bdf0e4c in do_load_image >> (boot_policy=<optimized out>, parent_image_handle=<optimized out>, >> image_handle=<optimized out>, >> source_size=<optimized out>, source_buffer=<optimized out>, >> file_path=<optimized out>) at ../../../grub-core/loader/efi/peimage.c:751 >> 751 in ../../../grub-core/loader/efi/peimage.c >> (grub gdb) c >> Continuing. >> >> Thread 1 hit Breakpoint 5.2, grub_error (n=GRUB_ERR_BAD_OS, >> fmt=0x23bdf1703 "section inside header") at ../../../grub-core/kern/err.c:41 >> warning: 41 ../../../grub-core/kern/err.c: No such file or directory >> (grub gdb) bt >> #0 grub_error (n=GRUB_ERR_BAD_OS, fmt=0x23bdf1703 "section inside >> header") at ../../../grub-core/kern/err.c:41 >> #1 0x000000023bdf0e34 in do_load_image (boot_policy=<optimized out>, >> parent_image_handle=<optimized out>, file_path=<optimized out>, >> source_buffer=<optimized out>, >> source_size=<optimized out>, image_handle=<optimized out>) at >> ../../../grub-core/loader/efi/peimage.c:747 >> #2 0x000000023bedabdc in grub_arch_efi_linux_boot_image (addr=9561964544, >> size=1081352, >> args=0x23bbb8b00 "placeholder dom0_mem=4G,max:4G loglvl=all >> guest_loglvl=all no-real-mode edd=off") at >> ../../../grub-core/loader/efi/linux.c:210 >> #3 0x000000023bff41bc in grub_loader_boot () at >> ../../../grub-core/commands/boot.c:211 >> #4 grub_loader_boot () at ../../../grub-core/commands/boot.c:190 >> #5 0x000000023bf42158 in grub_command_execute (name=0x23bf4e72c "boot", >> argc=0, argv=0x0 <_start>) at ../../../include/grub/command.h:126 >> #6 grub_menu_execute_entry (entry=entry@entry=0x23bd17660, >> auto_boot=auto_boot@entry=0) at ../../../grub-core/normal/menu.c:306 >> #7 0x000000023bf41e2c in show_menu (autobooted=<optimized out>, >> nested=<optimized out>, menu=<optimized out>) at >> ../../../grub-core/normal/menu.c:925 >> #8 grub_show_menu (menu=menu@entry=0x23bd1a940, nested=nested@entry=1, >> autoboot=autoboot@entry=0) at ../../../grub-core/normal/menu.c:940 >> #9 0x000000023bf408a8 in grub_normal_execute (config=<optimized out>, >> nested=nested@entry=1, batch=batch@entry=0) at >> ../../../grub-core/normal/main.c:291 >> #10 0x000000023bf32260 in grub_cmd_source (cmd=<optimized out>, argc=1, >> args=0x23bd1fcc8) at ../../../grub-core/commands/configfile.c:48 >> #11 grub_cmd_source (cmd=<optimized out>, argc=<optimized out>, >> args=0x23bd1fcc8) at ../../../grub-core/commands/configfile.c:30 >> #12 0x000000023bf48d0c in grub_script_execute_cmdline (cmd=<optimized >> out>) at ../../../grub-core/script/execute.c:1034 >> #13 0x000000023bf478c0 in grub_script_execute_cmd >> (cmd=cmd@entry=0x23bd190c8) at ../../../grub-core/script/execute.c:819 >> #14 0x000000023bf4874c in grub_script_execute_cmdlist (list=<optimized >> out>) at ../../../grub-core/script/execute.c:1079 >> #15 0x000000023bf478c0 in grub_script_execute_cmd (cmd=<optimized out>) at >> ../../../grub-core/script/execute.c:819 >> #16 0x000000023bf489b4 in grub_script_execute (script=<optimized out>) at >> ../../../grub-core/script/execute.c:1191 >> #17 0x000000023bf497fc in grub_normal_parse_line >> (line=line@entry=0x23bd20060 "configfile $prefix/grub.cfg", >> getline=getline@entry=0x23bf40430 <read_config_file_getline>, >> getline_data=getline_data@entry=0x23bd20380) at >> ../../../grub-core/script/main.c:36 >> #18 0x000000023bf409a0 in read_config_file (config=0x23bd20780 >> "(hd0,gpt1)/EFI/debian/grub.cfg") at ../../../grub-core/normal/main.c:179 >> #19 grub_normal_execute (config=config@entry=0x23bd20780 >> "(hd0,gpt1)/EFI/debian/grub.cfg", nested=nested@entry=0, batch=batch@entry=0) >> at ../../../grub-core/normal/main.c:277 >> #20 0x000000023bf40ca4 in grub_enter_normal_mode >> (config=config@entry=0x23bd20780 "(hd0,gpt1)/EFI/debian/grub.cfg") at >> ../../../grub-core/normal/main.c:304 >> #21 0x000000023bf40da0 in grub_try_normal_prefix (prefix=0x23bd209a0 >> "(hd0,gpt1)/EFI/debian") at ../../../grub-core/normal/main.c:356 >> #22 0x000000023bf40ea0 in grub_try_normal (variable=0x23bf4e492 "fw_path") >> at ../../../grub-core/normal/main.c:407 >> #23 grub_cmd_normal (cmd=<optimized out>, argc=0, argv=<optimized out>) at >> ../../../grub-core/normal/main.c:421 >> #24 grub_cmd_normal (cmd=<optimized out>, argc=<optimized out>, >> argv=<optimized out>) at ../../../grub-core/normal/main.c:412 >> #25 0x000000023c018fb8 in grub_command_execute (name=0x23c01ec6e ")", >> argc=0, argv=0x0 <_start>) at ../../../include/grub/command.h:126 >> #26 grub_load_normal_mode () at ../../../grub-core/kern/main.c:247 >> #27 grub_main () at ../../../grub-core/kern/main.c:339 >> #28 0x000000023c5c02c8 in ?? () >> #29 0x000000023c62a000 in ?? () >> #30 0xafafafaf6c617470 in ?? () >> Backtrace stopped: previous frame identical to this frame (corrupt stack?) >> >> Is it possible to override the peloader or does the Xen image need to be >> prepared a certain way? > > Well it needs to be a proper UEFI binary. The loader works for Linux > and for chainloading the Windows boot loader, we haven't tested other > binaries (except some small test binaries I suppose).
I'm able to load the hypervisor directly (it appears as a Linux kernel ARM64 boot executable Image, little-endian, 4K pages). Also using the upstream grub its able to load the hypervisor with the direct EFI load_image boot service. > Personally, I'm surprised Xen still exists in 2024, so don't expect > me to be very helpful here. There are still use cases for a "traditional" lowvisor type hypervisor that isn't entangled with a whole kernel. In our case there are automotive use cases which benefit from Xen's ability to partition and pin vCPUs to different domains. I don't know what Debian's policy is towards Xen but it did at least use to work. > In the error case you can see though, that one of the section > addresses in the Xen binary to be relocated points into the (PE) > header of the binary, which obviously seems wrong. > > So go check your PE sections and check which one is wrong? Is there any tooling for examining PE sections? -- Alex Bennée Virtualisation Tech Lead @ Linaro
