From 2aab9c3ca47dd4fcc19a8743c6e4d348640dd3fa Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 12 Oct 2017 14:22:04 +1100 Subject: scripts: fix faddr2line to work on last symbol If faddr2line is given a function name which is the last one listed by "nm -n", it will fail because it never finds the next symbol. So teach the awk script to catch that possibility, and use 'size' to provide the end point of the last function. Signed-off-by: NeilBrown Signed-off-by: Linus Torvalds --- scripts/faddr2line | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/faddr2line b/scripts/faddr2line index 29df825d375c..2f6ce802397d 100755 --- a/scripts/faddr2line +++ b/scripts/faddr2line @@ -103,11 +103,12 @@ __faddr2line() { # Go through each of the object's symbols which match the func name. # In rare cases there might be duplicates. + file_end=$(size -Ax $objfile | awk '$1 == ".text" {print $2}') while read symbol; do local fields=($symbol) local sym_base=0x${fields[0]} local sym_type=${fields[1]} - local sym_end=0x${fields[3]} + local sym_end=${fields[3]} # calculate the size local sym_size=$(($sym_end - $sym_base)) @@ -157,7 +158,7 @@ __faddr2line() { addr2line -fpie $objfile $addr | sed "s; $dir_prefix\(\./\)*; ;" DONE=1 - done < <(nm -n $objfile | awk -v fn=$func '$3 == fn { found=1; line=$0; start=$1; next } found == 1 { found=0; print line, $1 }') + done < <(nm -n $objfile | awk -v fn=$func -v end=$file_end '$3 == fn { found=1; line=$0; start=$1; next } found == 1 { found=0; print line, "0x"$1 } END {if (found == 1) print line, end; }') } [[ $# -lt 2 ]] && usage -- cgit v1.3-8-gc7d7 From 51962a9d437f0d580c04cd2c4abc2bd417200da2 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 13 Oct 2017 15:57:58 -0700 Subject: scripts/kallsyms.c: ignore symbol type 'n' gcc on aarch64 may emit synbols of type 'n' if the kernel is built with '-frecord-gcc-switches'. In most cases, those symbols are reported with nm as 000000000000000e n $d and with objdump as 0000000000000000 l d .GCC.command.line 0000000000000000 .GCC.command.line 000000000000000e l .GCC.command.line 0000000000000000 $d Those symbols are detected in is_arm_mapping_symbol() and ignored. However, if "--prefix-symbols=" is configured as well, the situation is different. For example, in efi/libstub, arm64 images are built with '--prefix-alloc-sections=.init --prefix-symbols=__efistub_'. In combination with '-frecord-gcc-switches', the symbols are now reported by nm as: 000000000000000e n __efistub_$d and by objdump as: 0000000000000000 l d .GCC.command.line 0000000000000000 .GCC.command.line 000000000000000e l .GCC.command.line 0000000000000000 __efistub_$d Those symbols are no longer ignored and included in the base address calculation. This results in a base address of 000000000000000e, which in turn causes kallsyms to abort with kallsyms failure: relative symbol value 0xffffff900800a000 out of range in relative mode The problem is seen in little endian arm64 builds with CONFIG_EFI enabled and with '-frecord-gcc-switches' set in KCFLAGS. Explicitly ignore symbols of type 'n' since those are clearly debug symbols. Link: http://lkml.kernel.org/r/1507136063-3139-1-git-send-email-linux@roeck-us.net Signed-off-by: Guenter Roeck Acked-by: Ard Biesheuvel Cc: Josh Poimboeuf Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/kallsyms.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 5d554419170b..9ee9bf7fd1a2 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -158,7 +158,7 @@ static int read_symbol(FILE *in, struct sym_entry *s) else if (str[0] == '$') return -1; /* exclude debugging symbols */ - else if (stype == 'N') + else if (stype == 'N' || stype == 'n') return -1; /* include the type field in the symbol name, so that it gets -- cgit v1.3-8-gc7d7