]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
cifs: allow syscalls to be restarted in __smb_send_rqst()
authorPaulo Alcantara <pc@cjr.nz>
Sat, 28 Nov 2020 18:57:06 +0000 (15:57 -0300)
committerSteve French <stfrench@microsoft.com>
Mon, 30 Nov 2020 21:23:31 +0000 (15:23 -0600)
commit6988a619f5b79e4efadea6e19dcfe75fbcd350b5
treeb96fd208d38e71366088e41e7078b9a79ae97efc
parentb65054597872ce3aefbc6a666385eabdf9e288da
cifs: allow syscalls to be restarted in __smb_send_rqst()

A customer has reported that several files in their multi-threaded app
were left with size of 0 because most of the read(2) calls returned
-EINTR and they assumed no bytes were read.  Obviously, they could
have fixed it by simply retrying on -EINTR.

We noticed that most of the -EINTR on read(2) were due to real-time
signals sent by glibc to process wide credential changes (SIGRT_1),
and its signal handler had been established with SA_RESTART, in which
case those calls could have been automatically restarted by the
kernel.

Let the kernel decide to whether or not restart the syscalls when
there is a signal pending in __smb_send_rqst() by returning
-ERESTARTSYS.  If it can't, it will return -EINTR anyway.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
fs/cifs/transport.c