From 16728aaba62e8b3b170735fdc3d8aa972835c136 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 28 Jul 2022 15:18:49 -0700 Subject: scsi: core: Make sure that hosts outlive targets Fix the race conditions between SCSI LLD kernel module unloading and SCSI device and target removal by making sure that SCSI hosts are destroyed after all associated target and device objects have been freed. Link: https://lore.kernel.org/r/20220728221851.1822295-3-bvanassche@acm.org Cc: Christoph Hellwig Cc: Ming Lei Cc: Mike Christie Cc: Hannes Reinecke Cc: John Garry Reviewed-by: Mike Christie Signed-off-by: Ming Lei Signed-off-by: Bart Van Assche [ bvanassche: Reworked Ming's patch and split it ] Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_scan.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/scsi/scsi_scan.c') diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 4c1efd6a3b0c..ac6059702d13 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -406,9 +406,14 @@ static void scsi_target_destroy(struct scsi_target *starget) static void scsi_target_dev_release(struct device *dev) { struct device *parent = dev->parent; + struct Scsi_Host *shost = dev_to_shost(parent); struct scsi_target *starget = to_scsi_target(dev); kfree(starget); + + if (atomic_dec_return(&shost->target_count) == 0) + wake_up(&shost->targets_wq); + put_device(parent); } @@ -523,6 +528,8 @@ static struct scsi_target *scsi_alloc_target(struct device *parent, starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; init_waitqueue_head(&starget->sdev_wq); + atomic_inc(&shost->target_count); + retry: spin_lock_irqsave(shost->host_lock, flags); -- cgit