On Tue, Dec 20, 2022 at 01:49:00PM +0100, Jakub Jelinek wrote: > On Tue, Dec 20, 2022 at 12:12:42PM +0000, Daniel P. Berrangé wrote: > > For KVM AMD SEV-SNP virtualization we're trying to get SVSM guest > > firmware built on Fedora. > > > > https://github.com/svsm-vtpm/linux-svsm > > > > It builds successfully on Ubuntu 22.04 (gcc 11.3.0) which is what upstream > > uses as their primary dev platform. On Fedora 37 (gcc 12.2.1) though, we're > > getting errors at the final link stage. To eliminate version as a factor, > > I also tried Fedora 35 with gcc 11.3.1 and got the same errors: > > > > gcc -m64 -nostdlib -Wl,-Tsrc/start/svsm.lds -Wl,--build-id=none -o svsm.bin.elf src/start/start.o target/x86_64-unknown-none/debug/liblinux_svsm.a -Wl,--start-group ./external/build/lib/libtpm.a ./external/build/lib/libplatform.a ./external/build/lib/libwolfssl.a ./external/build/lib/libcrt.a ./external/build/lib/libm.a -Wl,--end-group > > ./external/build/lib/libwolfssl.a(src_libwolfssl_la-sha256.o): in function `Transform_Sha256': > > sha256.c:(.text+0xba): relocation truncated to fit: R_X86_64_32 against `.rodata' > > ./external/build/lib/libwolfssl.a(src_libwolfssl_la-aes.o): in function `wc_AesEncrypt': > > aes.c:(.text+0x50): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0x68): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0x7e): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0x8c): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0x9e): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0xa9): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0xc5): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0xd3): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0xe9): relocation truncated to fit: R_X86_64_32S against `.rodata' > > aes.c:(.text+0xf8): additional relocation overflows omitted from the output > > collect2: error: ld returned 1 exit status > > make: *** [Makefile:54: svsm.bin.elf] Error 1 > > That would mean either that your text + data segment are larger than 2GB, or > src/start/svsm.lds you are using places the sections somewhere high in the > address space, incompatible with the x86-64 default -mcmodel=small. > Ubuntu defaults to -fpie -pie like we use in Fedora when hardening isn't > disabled through specs from redhat-rpm-config, so it uses a different > code model (small pic). > You can build stuff with -fpie and link with -pie if you want, or > -mcmodel=medium or -mcmodel=large etc., depends really on what src/start/svsm.lds > is doing and how large the binary is. > As documented: > '-mcmodel=small' > Generate code for the small code model: the program and its symbols > must be linked in the lower 2 GB of the address space. Pointers > are 64 bits. Programs can be statically or dynamically linked. > This is the default code model. > > '-mcmodel=medium' > Generate code for the medium model: the program is linked in the > lower 2 GB of the address space. Small symbols are also placed > there. Symbols with sizes larger than '-mlarge-data-threshold' are > put into large data or BSS sections and can be located above 2GB. > Programs can be statically or dynamically linked. > > '-mcmodel=large' > Generate code for the large model. This model makes no assumptions > about addresses and sizes of sections. > etc. The linker script has: SECTIONS { . = SVSM_GPA_LDS; and #ifndef SVSM_GPA_LDS #define SVSM_GPA_LDS 0x8000000000 #endif /* SVSM_GPA_LDS */ So, this is indeed incompatible with both small and medium code models, so everything that is linked into that binary should be compiled with -mcmodel=large and pay the code performance price for that. Jakub _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
