Commit aba80ad9d8 for qemu.org

commit aba80ad9d853e436047899177f92334379de4537
Author: Matt Turner <mattst88@gmail.com>
Date:   Sat Jul 25 20:55:27 2026 -0400

    linux-user: fix guards for the fsmount(2) syscall series

    The fsopen(), fsconfig(), fsmount() and fspick() implementations are
    guarded by defined(NR_fsopen) rather than defined(__NR_fsopen). No such
    macro exists, so the guard is never true and the entire series compiles
    out. Guests calling any of the four get -ENOSYS, which for example makes
    systemd's credential setup fail with EXIT_CREDENTIALS for most units.

    The strace bits for fsconfig() have the same typo.

    Check if FSCONFIG_SET_FLAG is defined to avoid build errors in the strace
    code on some older distributions (Helge).

    Fixes: 767c32fe6983 ("linux-user: implement fsmount(2) series of syscalls")
    Fixes: 6e0aa9f6c731 ("linux-user/strace: add fsmount series of syscalls")
    Signed-off-by: Matt Turner <mattst88@gmail.com>
    Reviewed-by: Helge Deller <deller@gmx.de>
    Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/linux-user/strace.c b/linux-user/strace.c
index 3a81cc95f4..bc43a95a77 100644
--- a/linux-user/strace.c
+++ b/linux-user/strace.c
@@ -4344,7 +4344,7 @@ print_statx(CPUArchState *cpu_env, const struct syscallname *name,
 }
 #endif

-#if defined(TARGET_NR_fsconfig) && defined(NR_fsconfig)
+#if defined(TARGET_NR_fsconfig) && defined(__NR_fsconfig) && defined(FSCONFIG_SET_FLAG)
 static void
 print_fsconfig_cmd_name(int cmd)
 {
diff --git a/linux-user/strace.list b/linux-user/strace.list
index e363892e0a..25ace05187 100644
--- a/linux-user/strace.list
+++ b/linux-user/strace.list
@@ -1725,7 +1725,7 @@
 #ifdef TARGET_NR_fsopen
 { TARGET_NR_fsopen, "fsopen", "%s(%s,%d)", NULL, NULL },
 #endif
-#if defined(TARGET_NR_fsconfig) && defined(NR_fsconfig)
+#if defined(TARGET_NR_fsconfig) && defined(__NR_fsconfig) && defined(FSCONFIG_SET_FLAG)
 { TARGET_NR_fsconfig, "fsconfig", NULL, print_fsconfig, NULL },
 #endif
 #ifdef TARGET_NR_fsmount
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 3da5530d42..740142825d 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -9740,7 +9740,7 @@ _syscall5(int, sys_move_mount, int, __from_dfd, const char *, __from_pathname,
            int, __to_dfd, const char *, __to_pathname, unsigned int, flag)
 #endif

-#if defined(TARGET_NR_fsopen) && defined(NR_fsopen)
+#if defined(TARGET_NR_fsopen) && defined(__NR_fsopen)
 #define __NR_sys_fsopen __NR_fsopen
 _syscall2(int, sys_fsopen, const char *, fs_name, unsigned int, flags);
 #define __NR_sys_fsconfig __NR_fsconfig
@@ -14485,7 +14485,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1,
         return do_map_shadow_stack(cpu_env, arg1, arg2, arg3);
 #endif

-#if defined(TARGET_NR_fsopen) && defined(NR_fsopen)
+#if defined(TARGET_NR_fsopen) && defined(__NR_fsopen)
     case TARGET_NR_fsopen:
         {
             p = lock_user_string(arg1);