On Tue, May 19, 2020 at 9:36 PM Saravana Kannan saravanak@google.com wrote:
Commit 21c27f06587d ("driver core: Fix SYNC_STATE_ONLY device link implementation") didn't completely fix STATELESS + SYNC_STATE_ONLY handling.
What looks like an optimization in that commit is actually a bug that causes an if condition to always take the else path. This prevents reordering of devices in the dpm_list when a DL_FLAG_STATELESS device link is create on top of an existing DL_FLAG_SYNC_STATE_ONLY device link.
Fixes: 21c27f06587d ("driver core: Fix SYNC_STATE_ONLY device link implementation") Signed-off-by: Saravana Kannan saravanak@google.com
Sigh... device links are tricky and hard! Sorry about the endless fixes :( Also, how was this not caught by the compiler as a warning?
-Saravana
drivers/base/core.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/base/core.c b/drivers/base/core.c index 83a3e0b62ce3..dfd4e94ef790 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -543,12 +543,14 @@ struct device_link *device_link_add(struct device *consumer,
if (flags & DL_FLAG_STATELESS) { kref_get(&link->kref);
link->flags |= DL_FLAG_STATELESS; if (link->flags & DL_FLAG_SYNC_STATE_ONLY &&!(link->flags & DL_FLAG_STATELESS))
!(link->flags & DL_FLAG_STATELESS)) {link->flags |= DL_FLAG_STATELESS; goto reorder;
else
} else {link->flags |= DL_FLAG_STATELESS; goto out;} } /*
Forgot to add stable@vger.kernel.org. Doing that now.
-Saravana