From 19ad4b2cb2f95202f615af57184c702fb098c011 Mon Sep 17 00:00:00 2001 From: Artur Paszkiewicz Date: Wed, 9 Apr 2014 17:14:59 +0200 Subject: [PATCH] Fix race between --create and --incremental This modifies locking in Create to eliminate a situation where --incremental can assemble a device between write_init_super() and add_disk(), which causes Create to fail. It sporadically occurs e.g. when metadata is written on a device, causing an udev change event which triggers mdadm --incremental. Signed-off-by: Artur Paszkiewicz Signed-off-by: NeilBrown --- Create.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) diff --git a/Create.c b/Create.c index 9247d46b..98bbdd40 100644 --- a/Create.c +++ b/Create.c @@ -740,7 +740,9 @@ int Create(struct supertype *st, char *mddev, map_update(&map, fd2devnm(mdfd), info.text_version, info.uuid, chosen_name); - map_unlock(&map); + /* Keep map locked until devices have been added to array + * to stop another mdadm from finding and using those devices. + */ if (s->bitmap_file && vers < 9003) { major_num = BITMAP_MAJOR_HOSTENDIAN; @@ -753,18 +755,18 @@ int Create(struct supertype *st, char *mddev, if (s->bitmap_file && strcmp(s->bitmap_file, "internal")==0) { if ((vers%100) < 2) { pr_err("internal bitmaps not supported by this kernel.\n"); - goto abort; + goto abort_locked; } if (!st->ss->add_internal_bitmap) { pr_err("internal bitmaps not supported with %s metadata\n", st->ss->name); - goto abort; + goto abort_locked; } if (!st->ss->add_internal_bitmap(st, &s->bitmap_chunk, c->delay, s->write_behind, bitmapsize, 1, major_num)) { pr_err("Given bitmap chunk size not supported.\n"); - goto abort; + goto abort_locked; } s->bitmap_file = NULL; } @@ -790,7 +792,7 @@ int Create(struct supertype *st, char *mddev, if (container_fd < 0) { pr_err("Cannot get exclusive " "open on container - weird.\n"); - goto abort; + goto abort_locked; } if (mdmon_running(st->container_devnm)) { if (c->verbose) @@ -805,7 +807,7 @@ int Create(struct supertype *st, char *mddev, if (rv) { pr_err("failed to set array info for %s: %s\n", mddev, strerror(errno)); - goto abort; + goto abort_locked; } if (s->bitmap_file) { @@ -816,18 +818,18 @@ int Create(struct supertype *st, char *mddev, c->delay, s->write_behind, bitmapsize, major_num)) { - goto abort; + goto abort_locked; } bitmap_fd = open(s->bitmap_file, O_RDWR); if (bitmap_fd < 0) { pr_err("weird: %s cannot be openned\n", s->bitmap_file); - goto abort; + goto abort_locked; } if (ioctl(mdfd, SET_BITMAP_FILE, bitmap_fd) < 0) { pr_err("Cannot set bitmap file for %s: %s\n", mddev, strerror(errno)); - goto abort; + goto abort_locked; } } @@ -884,7 +886,7 @@ int Create(struct supertype *st, char *mddev, pr_err("failed to open %s " "after earlier success - aborting\n", dv->devname); - goto abort; + goto abort_locked; } fstat(fd, &stb); inf->disk.major = major(stb.st_rdev); @@ -896,7 +898,7 @@ int Create(struct supertype *st, char *mddev, fd, dv->devname, dv->data_offset)) { ioctl(mdfd, STOP_ARRAY, NULL); - goto abort; + goto abort_locked; } st->ss->getinfo_super(st, inf, NULL); safe_mode_delay = inf->safe_mode_delay; @@ -922,7 +924,7 @@ int Create(struct supertype *st, char *mddev, pr_err("ADD_NEW_DISK for %s " "failed: %s\n", dv->devname, strerror(errno)); - goto abort; + goto abort_locked; } break; } @@ -939,7 +941,6 @@ int Create(struct supertype *st, char *mddev, * the subarray cursor such that ->getinfo_super once * again returns container info. */ - map_lock(&map); st->ss->getinfo_super(st, &info_new, NULL); if (st->ss->external && s->level != LEVEL_CONTAINER && !same_uuid(info_new.uuid, info.uuid, 0)) { @@ -964,12 +965,12 @@ int Create(struct supertype *st, char *mddev, info_new.uuid, path); free(path); } - map_unlock(&map); flush_metadata_updates(st); st->ss->free_super(st); } } + map_unlock(&map); free(infos); if (s->level == LEVEL_CONTAINER) { -- 2.39.2