From: Srikar Dronamraju srikar@linux.vnet.ibm.com
[ Upstream commit 2d77de1581bb5b470486edaf17a7d70151131afd ]
Commit 1d1a0e7c5100 ("scripts/faddr2line: Fix overlapping text section failures") can cause faddr2line to fail on ppc64le on some distributions, while it works fine on other distributions. The failure can be attributed to differences in the readelf output.
$ ./scripts/faddr2line vmlinux find_busiest_group+0x00 no match for find_busiest_group+0x00
On ppc64le, readelf adds the localentry tag before the symbol name on some distributions, and adds the localentry tag after the symbol name on other distributions. This problem has been discussed previously:
https://lore.kernel.org/bpf/20191211160133.GB4580@calabresa/
This problem can be overcome by filtering out the localentry tags in the readelf output. Similar fixes are already present in the kernel by way of the following commits:
1fd6cee127e2 ("libbpf: Fix VERSIONED_SYM_COUNT number parsing") aa915931ac3e ("libbpf: Fix readelf output parsing for Fedora")
[jpoimboe: rework commit log]
Fixes: 1d1a0e7c5100 ("scripts/faddr2line: Fix overlapping text section failures") Signed-off-by: Srikar Dronamraju srikar@linux.vnet.ibm.com Acked-by: Naveen N. Rao naveen.n.rao@linux.vnet.ibm.com Reviewed-by: Thadeu Lima de Souza Cascardo cascardo@canonical.com Link: https://lore.kernel.org/r/20220927075211.897152-1-srikar@linux.vnet.ibm.com Signed-off-by: Josh Poimboeuf jpoimboe@kernel.org Signed-off-by: Peter Zijlstra peterz@infradead.org Signed-off-by: Sasha Levin sashal@kernel.org --- scripts/faddr2line | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/scripts/faddr2line b/scripts/faddr2line index 5514c23f45c2..0e73aca4f908 100755 --- a/scripts/faddr2line +++ b/scripts/faddr2line @@ -74,7 +74,8 @@ command -v ${ADDR2LINE} >/dev/null 2>&1 || die "${ADDR2LINE} isn't installed" find_dir_prefix() { local objfile=$1
- local start_kernel_addr=$(${READELF} --symbols --wide $objfile | ${AWK} '$8 == "start_kernel" {printf "0x%s", $2}') + local start_kernel_addr=$(${READELF} --symbols --wide $objfile | sed 's/[.*]//' | + ${AWK} '$8 == "start_kernel" {printf "0x%s", $2}') [[ -z $start_kernel_addr ]] && return
local file_line=$(${ADDR2LINE} -e $objfile $start_kernel_addr) @@ -178,7 +179,7 @@ __faddr2line() { found=2 break fi - done < <(${READELF} --symbols --wide $objfile | ${AWK} -v sec=$sym_sec '$7 == sec' | sort --key=2) + done < <(${READELF} --symbols --wide $objfile | sed 's/[.*]//' | ${AWK} -v sec=$sym_sec '$7 == sec' | sort --key=2)
if [[ $found = 0 ]]; then warn "can't find symbol: sym_name: $sym_name sym_sec: $sym_sec sym_addr: $sym_addr sym_elf_size: $sym_elf_size" @@ -259,7 +260,7 @@ __faddr2line() {
DONE=1
- done < <(${READELF} --symbols --wide $objfile | ${AWK} -v fn=$sym_name '$4 == "FUNC" && $8 == fn') + done < <(${READELF} --symbols --wide $objfile | sed 's/[.*]//' | ${AWK} -v fn=$sym_name '$4 == "FUNC" && $8 == fn') }
[[ $# -lt 2 ]] && usage