From 30bd294fc6b310e7d59ed7b0f654257f3b202c9c Mon Sep 17 00:00:00 2001 From: Peter Rajnoha Date: Wed, 11 Apr 2012 09:12:02 +0000 Subject: [PATCH] Change message severity to log_very_verbose for missing dev info in udev db. Libudev does not provide transactions when querying udev database - once we get the list of block devices (devices/obtain_device_list_from_udev=1) and we iterate over the list to get more detailed information about device node and symlink names used etc., the device could be removed just in between we get the list and put a query for more info. In this case, libudev returns NULL value as the device does not exist anymore. Recently, we've added a warning message to reveal such situations. However, this could be misleading if the device is not related to the LVM action we're just processing - the non-related block device could be removed in parallel and this is not an error but a possible and normal operation. (N.B. This "missing info" should not happen when devices are related to the LVM action we're just processing since all such processing should be synchronized with udev and the udev db must always be in consistent state after the sync point. But we can't filter this situation out from others, non-related devices, so we have to lower the message verbosity here for a general solution.) --- WHATS_NEW | 1 + lib/device/dev-cache.c | 24 +++++++++++++++++++----- 2 files changed, 20 insertions(+), 5 deletions(-) diff --git a/WHATS_NEW b/WHATS_NEW index a0f437abf..e8af54317 100644 --- a/WHATS_NEW +++ b/WHATS_NEW @@ -1,5 +1,6 @@ Version 2.02.96 - ================================ + Change message severity to log_very_verbose for missing dev info in udev db. Fix problems when specifying PVs during RAID down-converts. Fix ability to handle failures in mirrored log (regression intro 2.02.89). Fix unlocking volume group in vgreduce in error path. diff --git a/lib/device/dev-cache.c b/lib/device/dev-cache.c index 29a619c7d..c92e11e9e 100644 --- a/lib/device/dev-cache.c +++ b/lib/device/dev-cache.c @@ -497,7 +497,7 @@ static int _insert_udev_dir(struct udev *udev, const char *dir) { struct udev_enumerate *udev_enum = NULL; struct udev_list_entry *device_entry, *symlink_entry; - const char *node_name, *symlink_name; + const char *entry_name, *node_name, *symlink_name; struct udev_device *device; int r = 1; @@ -508,20 +508,34 @@ static int _insert_udev_dir(struct udev *udev, const char *dir) udev_enumerate_scan_devices(udev_enum)) goto bad; + /* + * Report any missing information as "log_very_verbose" only, do not + * report it as a "warning" or "error" - the record could be removed + * by the time we ask for more info (node name, symlink name...). + * Whatever removes *any* block device in the system (even unrelated + * to our operation), we would have a warning/error on output then. + * That could be misleading. If there's really any problem with missing + * information from udev db, we can still have a look at the verbose log. + */ udev_list_entry_foreach(device_entry, udev_enumerate_get_list_entry(udev_enum)) { - if (!(device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(device_entry)))) { - log_warn("WARNING: udev failed to return a device entry."); + entry_name = udev_list_entry_get_name(device_entry); + + if (!(device = udev_device_new_from_syspath(udev, entry_name))) { + log_very_verbose("udev failed to return a device for entry %s.", + entry_name); continue; } if (!(node_name = udev_device_get_devnode(device))) - log_warn("WARNING: udev failed to return a device node."); + log_very_verbose("udev failed to return a device node for entry %s.", + entry_name); else r &= _insert(node_name, 0, 0); udev_list_entry_foreach(symlink_entry, udev_device_get_devlinks_list_entry(device)) { if (!(symlink_name = udev_list_entry_get_name(symlink_entry))) - log_warn("WARNING: udev failed to return a symlink name."); + log_very_verbose("udev failed to return a symlink name for entry %s.", + entry_name); else r &= _insert(symlink_name, 0, 0); }