From 69b2c33a77fa687feb41fafdbe187013aa812384 Mon Sep 17 00:00:00 2001
From: "Dmitry V. Levin" <ldv@altlinux.org>
Date: Tue, 7 Jan 2020 18:54:55 +0000
Subject: [PATCH] unwind-libdw: fix initialization of libdwfl cache
This fixes stack trace printing for early syscalls that precede
the first syscall from memory mapping or execve families.
* unwind-libdw.c (tcb_init): Set struct ctx.last_proc_updating
to a value different from mapping_generation so that libdwfl cache
is properly initialized before the first use.
* NEWS: Mention this fix.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1788636
---
Backport changes:
- NEWS hunk has been dropped.
---
NEWS | 2 ++
unwind-libdw.c | 2 +-
2 files changed, 3 insertions(+), 1 deletion(-)
Index: strace-4.24/unwind-libdw.c
===================================================================
--- strace-4.24.orig/unwind-libdw.c 2020-01-23 12:55:01.922338273 +0100
+++ strace-4.24/unwind-libdw.c 2020-01-23 12:55:06.131299136 +0100
@@ -69,7 +69,7 @@
struct ctx *ctx = xmalloc(sizeof(*ctx));
ctx->dwfl = dwfl;
- ctx->last_proc_updating = 0;
+ ctx->last_proc_updating = mapping_generation - 1;
return ctx;
}