poky/meta/recipes-devtools/qemu/qemu/fix_segv.patch

With qemu 8.2.0 we started seeing SEGV errors when compiling webkitgtk from
usermode qemu:

qemu-x86_64: QEMU internal SIGSEGV {code=MAPERR, addr=0x20}
Segmentation fault

By bisection, this was tracked down to:

commit 7b7a3366e142d3baeb3fd1d3660a50e7956c19eb
Author: Richard Henderson <richard.henderson@linaro.org>
Date:   Tue Aug 8 20:02:19 2023 -0700

    linux-user: Use walk_memory_regions for open_self_maps
    
    Replace the by-hand method of region identification with
    the official user-exec interface.  Cross-check the region
    provided to the callback with the interval tree from
    read_self_maps().
    
    Tested-by: Helge Deller <deller@gmx.de>
    Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
    Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

and specifically to 'n' being NULL. For now, just skip in that case
until a proper fix can be identified.

Reported upstream: https://www.mail-archive.com/qemu-devel@nongnu.org/msg1018813.html

YOCTO #15367

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Upstream-Status: Pending

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index e384e14248..2577fb770d 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -8085,6 +8085,9 @@ static int open_self_maps_2(void *opaque, target_ulong guest_start,
     while (1) {
         IntervalTreeNode *n =
             interval_tree_iter_first(d->host_maps, host_start, host_start);
+        if (!n) {
+            return 0;
+        }
         MapInfo *mi = container_of(n, MapInfo, itree);
         uintptr_t this_hlast = MIN(host_last, n->last);
         target_ulong this_gend = h2g(this_hlast) + 1;