xen/pvcalls: fix potential endless loop in pvcalls-front.c

Browse source

mutex_trylock() returns 1 if you take the lock and 0 if not. Assume you
take in_mutex on the first try, but you can't take out_mutex. Next times
you call mutex_trylock() in_mutex is going to fail. It's an endless
loop.

Solve the problem by waiting until the global refcount is 1 instead (the
refcount is 1 when the only active pvcalls frontend function is
pvcalls_front_release).

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

...

This commit is contained in:

Stefano Stabellini 2017-11-15 13:20:21 -08:00 • committed by Boris Ostrovsky

parent 24e7f84db0

commit 646d944c2e

1 changed files with 5 additions and 6 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

11

drivers/xen/pvcalls-front.c

View file