From: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx> commit 08f6c2b09ebd4b326dbe96d13f94fee8f9814c78 upstream. In case of errors in xenbus_init (e.g. missing xen_store_gfn parameter), we goto out_error but we forget to reset xen_store_domain_type to XS_UNKNOWN. As a consequence xenbus_probe_initcall and other initcalls will still try to initialize xenstore resulting into a crash at boot. [ 2.479830] Call trace: [ 2.482314] xb_init_comms+0x18/0x150 [ 2.486354] xs_init+0x34/0x138 [ 2.489786] xenbus_probe+0x4c/0x70 [ 2.498432] xenbus_probe_initcall+0x2c/0x7c [ 2.503944] do_one_initcall+0x54/0x1b8 [ 2.507358] kernel_init_freeable+0x1ac/0x210 [ 2.511617] kernel_init+0x28/0x130 [ 2.516112] ret_from_fork+0x10/0x20 Cc: <Stable@xxxxxxxxxxxxxxx> Cc: jbeulich@xxxxxxxx Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx> Link: https://lore.kernel.org/r/20211115222719.2558207-1-sstabellini@xxxxxxxxxx Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/xen/xenbus/xenbus_probe.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -764,7 +764,7 @@ static struct notifier_block xenbus_resu static int __init xenbus_init(void) { - int err = 0; + int err; uint64_t v = 0; xen_store_domain_type = XS_UNKNOWN; @@ -832,8 +832,10 @@ static int __init xenbus_init(void) */ proc_mkdir("xen", NULL); #endif + return 0; out_error: + xen_store_domain_type = XS_UNKNOWN; return err; }
