mdev: ignore events with "$SUBSYSTEM" == "firmware" && "$ACTION" == "remove"

function                                             old     new   delta
mdev_main                                            665     676     +11

diff --git a/util-linux/mdev.c b/util-linux/mdev.c
index b7b311aaaa5d4dfc6ad8ba44bb31aa45939a122e..6eaa66bf4ea684fc8a52c6701eab2d0b8643ea36 100644 (file)
--- a/util-linux/mdev.c
+++ b/util-linux/mdev.c
@@ -436,11 +436,10 @@ int mdev_main(int argc UNUSED_PARAM, char **argv)
                        ACTION_RECURSE | ACTION_FOLLOWLINKS,
                        fileAction, dirAction, temp, 0);
        } else {
+               char *fw;
                char *seq;
                char *action;
                char *env_path;
-               char seqbuf[sizeof(int)*3 + 2];
-               int seqlen = seqlen; /* for compiler */
 
                /* Hotplug:
                 * env ACTION=... DEVPATH=... [SEQNUM=...] mdev
@@ -451,14 +450,23 @@ int mdev_main(int argc UNUSED_PARAM, char **argv)
                env_path = getenv("DEVPATH");
                if (!action || !env_path)
                        bb_show_usage();
+               fw = getenv("FIRMWARE");
 
+               /* If it exists, does /dev/mdev.seq match $SEQNUM?
+                * If it does not match, earlier mdev is running
+                * in parallel, and we need to wait */
                seq = getenv("SEQNUM");
                if (seq) {
-                       int timeout = 2000 / 32;
+                       int timeout = 2000 / 32; /* 2000 msec */
                        do {
+                               int seqlen;
+                               char seqbuf[sizeof(int)*3 + 2];
+
                                seqlen = open_read_close("mdev.seq", seqbuf, sizeof(seqbuf-1));
-                               if (seqlen < 0)
+                               if (seqlen < 0) {
+                                       seq = NULL;
                                        break;
+                               }
                                seqbuf[seqlen] = '\0';
                                if (seqbuf[0] == '\n' /* seed file? */
                                 || strcmp(seq, seqbuf) == 0 /* correct idx? */
@@ -470,19 +478,22 @@ int mdev_main(int argc UNUSED_PARAM, char **argv)
                }
 
                snprintf(temp, PATH_MAX, "/sys%s", env_path);
-               if (!strcmp(action, "remove"))
-                       make_device(temp, 1);
-               else if (!strcmp(action, "add")) {
+               if (strcmp(action, "remove") == 0) {
+                       /* Ignoring "remove firmware". It was reported
+                        * to happen and to cause erroneous deletion
+                        * of device nodes. */
+                       if (!fw)
+                               make_device(temp, 1);
+               }
+               else if (strcmp(action, "add") == 0) {
                        make_device(temp, 0);
-
                        if (ENABLE_FEATURE_MDEV_LOAD_FIRMWARE) {
-                               char *fw = getenv("FIRMWARE");
                                if (fw)
                                        load_firmware(fw, temp);
                        }
                }
 
-               if (seq && seqlen >= 0) {
+               if (seq) {
                        xopen_xwrite_close("mdev.seq", utoa(xatou(seq) + 1));
                }
        }