udevd catches close-after-write inotify events and generates "change" uvents for such devices, which may cause extra unnecessary and unwanted udev activity. Therefore use O_RDONLY file descriptors for PRIN and PROUT commands. This works just as well as O_WRONLY. sg_persist has supported the --readonly option for years. Signed-off-by: Martin Wilck <mwilck@xxxxxxxx> --- libmpathpersist/mpath_pr_ioctl.c | 4 ++-- mpathpersist/main.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/libmpathpersist/mpath_pr_ioctl.c b/libmpathpersist/mpath_pr_ioctl.c index 76271ff1..e641ce62 100644 --- a/libmpathpersist/mpath_pr_ioctl.c +++ b/libmpathpersist/mpath_pr_ioctl.c @@ -52,7 +52,7 @@ int prout_do_scsi_ioctl(char * dev, int rq_servact, int rq_scope, int fd = -1; snprintf(devname, FILE_NAME_SIZE, "/dev/%s",dev); - fd = open(devname, O_WRONLY); + fd = open(devname, O_RDONLY); if(fd < 0){ condlog (1, "%s: unable to open device.", dev); return MPATH_PR_FILE_ERROR; @@ -308,7 +308,7 @@ int prin_do_scsi_ioctl(char * dev, int rq_servact, struct prin_resp * resp, int {MPATH_PRIN_CMD, 0, 0, 0, 0, 0, 0, 0, 0, 0}; snprintf(devname, FILE_NAME_SIZE, "/dev/%s",dev); - fd = open(devname, O_WRONLY); + fd = open(devname, O_RDONLY); if(fd < 0){ condlog(0, "%s: Unable to open device ", dev); return MPATH_PR_FILE_ERROR; diff --git a/mpathpersist/main.c b/mpathpersist/main.c index 5b37f3ae..34caa16c 100644 --- a/mpathpersist/main.c +++ b/mpathpersist/main.c @@ -380,7 +380,7 @@ int main (int argc, char * argv[]) } /* open device */ - if ((fd = open (device_name, O_WRONLY)) < 0) + if ((fd = open (device_name, O_RDONLY)) < 0) { fprintf (stderr, "%s: error opening file (rw) fd=%d\n", device_name, fd); -- 2.17.1 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel