676799a00d
Current code doesn't check size of elf sections and may perform needless actions of zero-sized memory allocation and similar. The bigger issue is that alignment requirement of a zero-sized section gets effectively applied to the next section if it has smaller alignment requirement. But other tools, like gdb and consequently kgdb, completely ignore zero-sized sections and thus may map symbols to addresses differently. Zero-sized sections are not typical in general. Their typical (only, even) cause in FreeBSD modules is inline assembly that creates custom sections which is found in pcpu.h and vnet.h. Mere inclusion of one of those header files produces a custom section in elf output. If there is no actual use for the section in a given module, then the section remains empty. Better solution is to avoid creating zero-sized sections altogether, which is in plans. Preloaded modules are handled in boot code (load_elf_obj.c), while dynamically loaded modules are handled by kernel (link_elf_obj.c). Based on code by: np MFC after: 3 weeks |
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| .. | ||
| bcache.c | ||
| boot.c | ||
| bootstrap.h | ||
| commands.c | ||
| console.c | ||
| dev_net.c | ||
| dev_net.h | ||
| devopen.c | ||
| help.common | ||
| interp_backslash.c | ||
| interp_forth.c | ||
| interp_parse.c | ||
| interp.c | ||
| isapnp.c | ||
| isapnp.h | ||
| load_elf32_obj.c | ||
| load_elf32.c | ||
| load_elf64_obj.c | ||
| load_elf64.c | ||
| load_elf_obj.c | ||
| load_elf.c | ||
| loader.8 | ||
| ls.c | ||
| Makefile.inc | ||
| md.c | ||
| merge_help.awk | ||
| misc.c | ||
| module.c | ||
| newvers.sh | ||
| panic.c | ||
| pnp.c | ||
| reloc_elf32.c | ||
| reloc_elf64.c | ||
| reloc_elf.c | ||
| ufsread.c | ||