[08/18] sd: use __register_blkdev to avoid a modprobe for an unregistered dev_t
diff mbox series

Message ID 20201029145841.144173-9-hch@lst.de
State In Next
Commit 140ea3bbf39ab4cf7d6340ae2136940092b53a94
Headers show
Series
  • [01/18] block: cleanup del_gendisk a bit
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Commit Message

Christoph Hellwig Oct. 29, 2020, 2:58 p.m. UTC
Switch from using blk_register_region to the probe callback passed to
__register_blkdev to disable the request_module call for an unclaimed
dev_t in the SD majors.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 drivers/scsi/sd.c | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

Comments

Martin K. Petersen Oct. 30, 2020, 2:13 a.m. UTC | #1
Christoph,

> Switch from using blk_register_region to the probe callback passed to
> __register_blkdev to disable the request_module call for an unclaimed
> dev_t in the SD majors.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Hannes Reinecke <hare@suse.de>

Acked-by: Martin K. Petersen <martin.petersen@oracle.com>

Patch
diff mbox series

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 656bcf4940d6d1..106a9cda0eb7ed 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -630,13 +630,11 @@  static struct scsi_driver sd_template = {
 };
 
 /*
- * Dummy kobj_map->probe function.
- * The default ->probe function will call modprobe, which is
- * pointless as this module is already loaded.
+ * Don't request a new module, as that could deadlock in multipath
+ * environment.
  */
-static struct kobject *sd_default_probe(dev_t devt, int *partno, void *data)
+static void sd_default_probe(dev_t devt)
 {
-	return NULL;
 }
 
 /*
@@ -3528,9 +3526,6 @@  static int sd_remove(struct device *dev)
 
 	free_opal_dev(sdkp->opal_dev);
 
-	blk_register_region(devt, SD_MINORS, NULL,
-			    sd_default_probe, NULL, NULL);
-
 	mutex_lock(&sd_ref_mutex);
 	dev_set_drvdata(dev, NULL);
 	put_device(&sdkp->dev);
@@ -3720,11 +3715,9 @@  static int __init init_sd(void)
 	SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
 
 	for (i = 0; i < SD_MAJORS; i++) {
-		if (register_blkdev(sd_major(i), "sd") != 0)
+		if (__register_blkdev(sd_major(i), "sd", sd_default_probe))
 			continue;
 		majors++;
-		blk_register_region(sd_major(i), SD_MINORS, NULL,
-				    sd_default_probe, NULL, NULL);
 	}
 
 	if (!majors)
@@ -3797,10 +3790,8 @@  static void __exit exit_sd(void)
 
 	class_unregister(&sd_disk_class);
 
-	for (i = 0; i < SD_MAJORS; i++) {
-		blk_unregister_region(sd_major(i), SD_MINORS);
+	for (i = 0; i < SD_MAJORS; i++)
 		unregister_blkdev(sd_major(i), "sd");
-	}
 }
 
 module_init(init_sd);