From ad1016b014d4c33dee3be66376bf9f3394160501 Mon Sep 17 00:00:00 2001
From: Jason Dillaman <dillaman@redhat.com>
Date: Mon, 21 Sep 2020 14:05:17 -0400
Subject: [PATCH] librbd: skip cache initialization if data IoCtx is invalid

This resolves the potential for an assertion failure in the cache
constructors that occurs when the data IoCtx is not valid. Errors
are deferred until actual IOs are issued against the invalid data
pool.

Signed-off-by: Jason Dillaman <dillaman@redhat.com>
---
 src/librbd/image/OpenRequest.cc  | 4 ++--
 src/librbd/plugin/ParentCache.cc | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/librbd/image/OpenRequest.cc b/src/librbd/image/OpenRequest.cc
index 046d37d4ba7ca..9b8e098108339 100644
--- a/src/librbd/image/OpenRequest.cc
+++ b/src/librbd/image/OpenRequest.cc
@@ -558,8 +558,8 @@ Context* OpenRequest<I>::handle_init_plugin_registry(int *result) {
 
 template <typename I>
 Context *OpenRequest<I>::send_init_cache(int *result) {
-  // cache is disabled or parent image context
-  if (!m_image_ctx->cache || m_image_ctx->child != nullptr) {
+  if (!m_image_ctx->cache || m_image_ctx->child != nullptr ||
+      !m_image_ctx->data_ctx.is_valid()) {
     return send_register_watch(result);
   }
 
diff --git a/src/librbd/plugin/ParentCache.cc b/src/librbd/plugin/ParentCache.cc
index 9e1197933f59e..0c50c8e719705 100644
--- a/src/librbd/plugin/ParentCache.cc
+++ b/src/librbd/plugin/ParentCache.cc
@@ -38,7 +38,8 @@ void ParentCache<I>::init(I* image_ctx, Api<I>& api, HookPoints* hook_points,
   m_image_ctx = image_ctx;
   bool parent_cache_enabled = m_image_ctx->config.template get_val<bool>(
     "rbd_parent_cache_enabled");
-  if (m_image_ctx->child == nullptr || !parent_cache_enabled) {
+  if (m_image_ctx->child == nullptr || !parent_cache_enabled ||
+      !m_image_ctx->data_ctx.is_valid()) {
     on_finish->complete(0);
     return;
   }
-- 
2.39.5