[lkml]   [2019]   [Apr]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] PM / devfreq: Return -ENODEV from try_then_request_governor
Callers don't expect it to return NULL, but an error code.

Fixes Oops such as the one below, when one tries to set a governor that
isn't available:

Unable to handle kernel NULL pointer dereference at virtual address 00000018

[<c0dcf718>] (governor_store) from [<c0539558>] (kernfs_fop_write+0x100/0x1e0)
[<c0539558>] (kernfs_fop_write) from [<c04b09b4>] (__vfs_write+0x2c/0x17c)
[<c04b09b4>] (__vfs_write) from [<c04b33fc>] (vfs_write+0xa4/0x184)
[<c04b33fc>] (vfs_write) from [<c04b361c>] (ksys_write+0x4c/0xac)
[<c04b361c>] (ksys_write) from [<c0301000>] (ret_fast_syscall+0x0/0x28)

Signed-off-by: Tomeu Vizoso <>
Fixes: 23c7b54ca1cd ("PM / devfreq: Fix devfreq_add_device() when drivers are built as modules.")
Reported-by: Alyssa Rosenzweig <>
Cc: Enric Balletbo i Serra <>
drivers/devfreq/devfreq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 0ae3de76833b..5539e9be718d 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -254,7 +254,7 @@ static struct devfreq_governor *try_then_request_governor(const char *name)
/* Restore previous state before return */
if (err)
- return NULL;
+ return ERR_PTR(-ENODEV);

governor = find_devfreq_governor(name);
 \ /
  Last update: 2019-04-23 10:12    [W:0.083 / U:14.716 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site