On Mon, Feb 15, 2021 at 04:44:46PM -0500, Steven Rostedt wrote: > From: "Steven Rostedt (VMware)" <rost...@goodmis.org> > > Starting with binutils 2.36, sections were being removed if they had weak > functions that were optimized out. Unfortunately, these weak functions would > leave references to mcount/fentry calls, that would make recordmcount fail > to find the symbol that matched the call to fentry.
Binutils 2.36 isn't removing sections, just section *symbols*. > Before returning the symbol of the section to create the mcount location, > check if that section size is greater than zero. If it has no size, skip > referencing that mcount call location. How does this even work? The .text.unlikely section isn't empty: # readelf -SW kernel/kexec_file.o Section Headers: [Nr] Name Type Address Off Size ES Flg Lk Inf Al [ 0] NULL 0000000000000000 000000 000000 00 0 0 0 [ 1] .text PROGBITS 0000000000000000 000040 001acf 00 AX 0 0 1 [ 2] .rela.text RELA 0000000000000000 0049e0 001b30 18 I 27 1 8 [ 3] .data PROGBITS 0000000000000000 001b20 000e80 00 WA 0 0 32 [ 4] .rela.data RELA 0000000000000000 006510 0010e0 18 I 27 3 8 [ 5] .bss NOBITS 0000000000000000 0029a0 000060 00 WA 0 0 32 [ 6] .rodata PROGBITS 0000000000000000 0029a0 000b80 00 A 0 0 32 [ 7] .rodata.str1.1 PROGBITS 0000000000000000 003520 0001c6 01 AMS 0 0 1 [ 8] .text.unlikely PROGBITS 0000000000000000 0036e6 000038 00 AX 0 0 1 -- Josh