From a8563dba75c92e04dbc63bdbee03b0ebc8889fa8 Mon Sep 17 00:00:00 2001 From: Xi Ruoyao Date: Fri, 27 Dec 2024 16:26:28 +0800 Subject: [PATCH] LoongArch: Fix broken DESC => IE transition for 2.43 branch If code compiled with -fPIC -mtls-dialect=desc is linked into a PDE or PIE, and the code refers to external DSO symbols, we can produce broken link unit as check_relocs expects DESC => IE transition to happen and emits a TLS IE entry in the GOT, but a too early "continue" in relax_section actually jumps over the DESC => IE transition so the code sequence is unchanged and still expecting a TLS descriptor (instead of an IE entry) in the GOT. The bug is already fixed in master branch by commit 5c3d09c1855b ("LoongArch: Optimize the relaxation process") so this fix is only needed for the 2.43 branch. Reported-by: Icenowy Zheng Closes: https://gcc.gnu.org/PR118114 Tested-by: Icenowy Zheng Signed-off-by: Xi Ruoyao --- bfd/elfnn-loongarch.c | 45 ++++++++++++++++++++++--------------------- 1 file changed, 23 insertions(+), 22 deletions(-) diff --git a/bfd/elfnn-loongarch.c b/bfd/elfnn-loongarch.c index 312707bb00b..7760b5279f8 100644 --- a/bfd/elfnn-loongarch.c +++ b/bfd/elfnn-loongarch.c @@ -5325,8 +5325,8 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, for (unsigned int i = 0; i < sec->reloc_count; i++) { char symtype; - bfd_vma symval; - asection *sym_sec; + bfd_vma symval = 0; /* "= 0" for https://gcc.gnu.org/PR118216 */ + asection *sym_sec = NULL; bool local_got = false; Elf_Internal_Rela *rel = relocs + i; struct elf_link_hash_entry *h = NULL; @@ -5418,14 +5418,33 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, symval = h->root.u.def.value; sym_sec = h->root.u.def.section; } - else - continue; if (h && LARCH_REF_LOCAL (info, h)) local_got = true; symtype = h->type; } + /* If the conditions for tls type transition are met, type + transition is performed instead of relax. + During the transition from DESC->IE/LE, there are 2 situations + depending on the different configurations of the relax/norelax + option. + If the -relax option is used, the extra nops will be removed, + and this transition is performed in pass 0. + If the --no-relax option is used, nop will be retained, and + this transition is performed in pass 1. */ + if (IS_LOONGARCH_TLS_TRANS_RELOC (r_type) + && (i + 1 != sec->reloc_count) + && ELFNN_R_TYPE (rel[1].r_info) == R_LARCH_RELAX + && loongarch_can_trans_tls (abfd, info, h, r_symndx, r_type)) + { + loongarch_tls_perform_trans (abfd, sec, rel, h, info); + r_type = ELFNN_R_TYPE (rel->r_info); + } + + if (!sym_sec) + continue; + if (sym_sec->sec_info_type == SEC_INFO_TYPE_MERGE && (sym_sec->flags & SEC_MERGE)) { @@ -5453,24 +5472,6 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, symval += sec_addr (sym_sec); - /* If the conditions for tls type transition are met, type - transition is performed instead of relax. - During the transition from DESC->IE/LE, there are 2 situations - depending on the different configurations of the relax/norelax - option. - If the -relax option is used, the extra nops will be removed, - and this transition is performed in pass 0. - If the --no-relax option is used, nop will be retained, and - this transition is performed in pass 1. */ - if (IS_LOONGARCH_TLS_TRANS_RELOC (r_type) - && (i + 1 != sec->reloc_count) - && ELFNN_R_TYPE (rel[1].r_info) == R_LARCH_RELAX - && loongarch_can_trans_tls (abfd, info, h, r_symndx, r_type)) - { - loongarch_tls_perform_trans (abfd, sec, rel, h, info); - r_type = ELFNN_R_TYPE (rel->r_info); - } - switch (r_type) { case R_LARCH_ALIGN: