1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
From 0bccc3722bdd88e8ae995e77ef9f7b77ee4cbdee Mon Sep 17 00:00:00 2001
From: Daniel Golle <daniel@makrotopia.org>
Date: Wed, 7 Apr 2021 22:45:54 +0100
Subject: [PATCH 2/2] mtd: blktrans: call add disks after mtd device
To: linux-mtd@lists.infradead.org
Cc: Vignesh Raghavendra <vigneshr@ti.com>,
Richard Weinberger <richard@nod.at>,
Miquel Raynal <miquel.raynal@bootlin.com>,
David Woodhouse <dwmw2@infradead.org>
Calling device_add_disk while holding mtd_table_mutex leads
to deadlock in case part_bits!=0 as block partition parsers
will try to open the newly created disks, trying to acquire
mutex once again.
Move device_add_disk to additional function called after
add partitions of an MTD device have been added and locks
have been released.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
drivers/mtd/mtd_blkdevs.c | 33 ++++++++++++++++++++++++++-------
drivers/mtd/mtdcore.c | 3 +++
include/linux/mtd/blktrans.h | 1 +
3 files changed, 30 insertions(+), 7 deletions(-)
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -384,13 +384,6 @@ int add_mtd_blktrans_dev(struct mtd_blkt
if (new->readonly)
set_disk_ro(gd, 1);
- device_add_disk(&new->mtd->dev, gd, NULL);
-
- if (new->disk_attributes) {
- ret = sysfs_create_group(&disk_to_dev(gd)->kobj,
- new->disk_attributes);
- WARN_ON(ret);
- }
return 0;
out_free_tag_set:
@@ -402,6 +395,27 @@ out_list_del:
return ret;
}
+void register_mtd_blktrans_devs(void)
+{
+ struct mtd_blktrans_ops *tr;
+ struct mtd_blktrans_dev *dev, *next;
+ int ret;
+
+ list_for_each_entry(tr, &blktrans_majors, list) {
+ list_for_each_entry_safe(dev, next, &tr->devs, list) {
+ if (disk_live(dev->disk))
+ continue;
+
+ device_add_disk(&dev->mtd->dev, dev->disk, NULL);
+ if (dev->disk_attributes) {
+ ret = sysfs_create_group(&disk_to_dev(dev->disk)->kobj,
+ dev->disk_attributes);
+ WARN_ON(ret);
+ }
+ }
+ }
+}
+
int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old)
{
unsigned long flags;
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -31,6 +31,7 @@
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
+#include <linux/mtd/blktrans.h>
#include "mtdcore.h"
@@ -1073,6 +1074,8 @@ int mtd_device_parse_register(struct mtd
ret = mtd_otp_nvmem_add(mtd);
+ register_mtd_blktrans_devs();
+
out:
if (ret && device_is_registered(&mtd->dev))
del_mtd_device(mtd);
--- a/include/linux/mtd/blktrans.h
+++ b/include/linux/mtd/blktrans.h
@@ -76,6 +76,7 @@ extern int deregister_mtd_blktrans(struc
extern int add_mtd_blktrans_dev(struct mtd_blktrans_dev *dev);
extern int del_mtd_blktrans_dev(struct mtd_blktrans_dev *dev);
extern int mtd_blktrans_cease_background(struct mtd_blktrans_dev *dev);
+extern void register_mtd_blktrans_devs(void);
/**
* module_mtd_blktrans() - Helper macro for registering a mtd blktrans driver
|
