This is an update version of last version to fix the handling of polling errors in vhost/vhost_net.
Currently, vhost and vhost_net ignore polling errors which can lead kernel crashing when it tries to remove itself from waitqueue after the polling failure. Fix this by: - examing the POLLERR when setting backend and report erros to userspace - let tun always add to waitqueue in .poll() after the queue is created even if it was detached. Changes from V6: - don't use RCU to protect the tfile->detached. Changes from V5: - use rcu_dereference() instead of the wrong rtnl_dereference() in data path - test with CONFIG_PROVE_RCU Changes from V4: - check the detached state by tfile->detached and protect it by RCU Changes from V3: - make a smaller patch that doesn't touch the whole polling state and only check the polliner errors in backend setting. - add a patch that allows tuntap to do polling/reading/writing when detached which could simplify the work of its user. Changes from v2: - check poll->wqh instead of the wrong assumption about POLLERR and waitqueue - drop the whole tx polling state check since it was replaced by the wqh checking - drop the buggy tuntap patch Changes from v1: - restore the state before the ioctl when vhost_init_used() fails - log the error when meet polling errors in the data path - don't put into waitqueue when tun_chr_poll() return POLLERR Jason Wang (3): vhost_net: correct error handling in vhost_net_set_backend() vhost_net: handle polling errors when setting backend tuntap: allow polling/writing/reading when detached drivers/net/tun.c | 25 ++++++++++++++++--------- drivers/vhost/net.c | 41 ++++++++++++++++++++++++++++------------- drivers/vhost/vhost.c | 18 +++++++++++++++--- drivers/vhost/vhost.h | 2 +- 4 files changed, 60 insertions(+), 26 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
