diff --git a/kexec-tools-2.0.23-s390_handle_R_390_PLT32DBL_reloc_entries_in_machine_apply_elf_rel_.patch b/kexec-tools-2.0.23-s390_handle_R_390_PLT32DBL_reloc_entries_in_machine_apply_elf_rel_.patch new file mode 100644 index 0000000..10bc5ef --- /dev/null +++ b/kexec-tools-2.0.23-s390_handle_R_390_PLT32DBL_reloc_entries_in_machine_apply_elf_rel_.patch @@ -0,0 +1,95 @@ +commit 186e7b0752d8fce1618fa37519671c834c46340e +Author: Alexander Egorenkov +Date: Wed Dec 15 18:48:53 2021 +0100 + + s390: handle R_390_PLT32DBL reloc entries in machine_apply_elf_rel() + + Starting with gcc 11.3, the C compiler will generate PLT-relative function + calls even if they are local and do not require it. Later on during linking, + the linker will replace all PLT-relative calls to local functions with + PC-relative ones. Unfortunately, the purgatory code of kexec/kdump is + not being linked as a regular executable or shared library would have been, + and therefore, all PLT-relative addresses remain in the generated purgatory + object code unresolved. This in turn lets kexec-tools fail with + "Unknown rela relocation: 0x14 0x73c0901c" for such relocation types. + + Furthermore, the clang C compiler has always behaved like described above + and this commit should fix the purgatory code built with the latter. + + Because the purgatory code is no regular executable or shared library, + contains only calls to local functions and has no PLT, all R_390_PLT32DBL + relocation entries can be resolved just like a R_390_PC32DBL one. + + * https://refspecs.linuxfoundation.org/ELF/zSeries/lzsabi0_zSeries/x1633.html#AEN1699 + + Relocation entries of purgatory code generated with gcc 11.3 + ------------------------------------------------------------ + + $ readelf -r purgatory/purgatory.o + + Relocation section '.rela.text' at offset 0x6e8 contains 27 entries: + Offset Info Type Sym. Value Sym. Name + Addend + 00000000000c 000300000013 R_390_PC32DBL 0000000000000000 .data + 2 + 00000000001a 001000000014 R_390_PLT32DBL 0000000000000000 sha256_starts + 2 + 000000000030 001100000014 R_390_PLT32DBL 0000000000000000 sha256_update + 2 + 000000000046 001200000014 R_390_PLT32DBL 0000000000000000 sha256_finish + 2 + 000000000050 000300000013 R_390_PC32DBL 0000000000000000 .data + 102 + 00000000005a 001300000014 R_390_PLT32DBL 0000000000000000 memcmp + 2 + ... + 000000000118 001600000014 R_390_PLT32DBL 0000000000000000 setup_arch + 2 + 00000000011e 000300000013 R_390_PC32DBL 0000000000000000 .data + 2 + 00000000012c 000f00000014 R_390_PLT32DBL 0000000000000000 verify_sha256_digest + 2 + 000000000142 001700000014 R_390_PLT32DBL 0000000000000000 + post_verification[...] + 2 + + Relocation entries of purgatory code generated with gcc 11.2 + ------------------------------------------------------------ + + $ readelf -r purgatory/purgatory.o + + Relocation section '.rela.text' at offset 0x6e8 contains 27 entries: + Offset Info Type Sym. Value Sym. Name + Addend + 00000000000e 000300000013 R_390_PC32DBL 0000000000000000 .data + 2 + 00000000001c 001000000013 R_390_PC32DBL 0000000000000000 sha256_starts + 2 + 000000000036 001100000013 R_390_PC32DBL 0000000000000000 sha256_update + 2 + 000000000048 001200000013 R_390_PC32DBL 0000000000000000 sha256_finish + 2 + 000000000052 000300000013 R_390_PC32DBL 0000000000000000 .data + 102 + 00000000005c 001300000013 R_390_PC32DBL 0000000000000000 memcmp + 2 + ... + 00000000011a 001600000013 R_390_PC32DBL 0000000000000000 setup_arch + 2 + 000000000120 000300000013 R_390_PC32DBL 0000000000000000 .data + 122 + 000000000130 000f00000013 R_390_PC32DBL 0000000000000000 verify_sha256_digest + 2 + 000000000146 001700000013 R_390_PC32DBL 0000000000000000 post_verification[...] + 2 + + Corresponding s390 kernel discussion: + * https://lore.kernel.org/linux-s390/20211208105801.188140-1-egorenar@linux.ibm.com/T/#u + + Signed-off-by: Alexander Egorenkov + Reported-by: Tao Liu + Suggested-by: Philipp Rudo + Reviewed-by: Philipp Rudo + [hca@linux.ibm.com: changed commit message as requested by Philipp Rudo] + Signed-off-by: Heiko Carstens + Signed-off-by: Simon Horman + +diff --git a/kexec/arch/s390/kexec-elf-rel-s390.c b/kexec/arch/s390/kexec-elf-rel-s390.c +index a5e1b73455785ae3bc3aa72b3beee13ae202e82f..91ba86a9991dad4271b834fc3b24861c40309e52 100644 +--- a/kexec/arch/s390/kexec-elf-rel-s390.c ++++ b/kexec/arch/s390/kexec-elf-rel-s390.c +@@ -56,6 +56,7 @@ void machine_apply_elf_rel(struct mem_ehdr *UNUSED(ehdr), + case R_390_PC16: /* PC relative 16 bit. */ + case R_390_PC16DBL: /* PC relative 16 bit shifted by 1. */ + case R_390_PC32DBL: /* PC relative 32 bit shifted by 1. */ ++ case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */ + case R_390_PC32: /* PC relative 32 bit. */ + case R_390_PC64: /* PC relative 64 bit. */ + val -= address; +@@ -63,7 +64,7 @@ void machine_apply_elf_rel(struct mem_ehdr *UNUSED(ehdr), + *(unsigned short *) loc = val; + else if (r_type == R_390_PC16DBL) + *(unsigned short *) loc = val >> 1; +- else if (r_type == R_390_PC32DBL) ++ else if (r_type == R_390_PC32DBL || r_type == R_390_PLT32DBL) + *(unsigned int *) loc = val >> 1; + else if (r_type == R_390_PC32) + *(unsigned int *) loc = val; diff --git a/kexec-tools.spec b/kexec-tools.spec index 0ef93f9..aabb369 100644 --- a/kexec-tools.spec +++ b/kexec-tools.spec @@ -103,6 +103,7 @@ Requires: systemd-udev%{?_isa} # # Patches 401 through 500 are meant for s390 kexec-tools enablement # +Patch401: ./kexec-tools-2.0.23-s390_handle_R_390_PLT32DBL_reloc_entries_in_machine_apply_elf_rel_.patch # # Patches 501 through 600 are meant for ARM kexec-tools enablement @@ -126,6 +127,8 @@ mkdir -p -m755 kcp tar -z -x -v -f %{SOURCE9} tar -z -x -v -f %{SOURCE19} +%patch401 -p1 + %ifarch ppc %define archdef ARCH=ppc %endif