2012-02-14 04:12:04

by Yang Bai

Subject: [PATCH] scsi: if sd card is removed, do not revalidate it

During revalidating, if sd card is removed, scsi_device
will be NULL, so we should not revalidate or it will cause
a panic.
This problem is report at:
http://comments.gmane.org/gmane.linux.kernel/1250235

Signed-off-by: Yang Bai <[email protected]>
---
drivers/scsi/sd.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index c691fb5..470339c 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2370,10 +2370,10 @@ static int sd_revalidate_disk(struct gendisk *disk)
"sd_revalidate_disk\n"));

/*
- * If the device is offline, don't try and read capacity or any
+ * If the device is removed or offline, don't try and read capacity or any
* of the other niceties.
*/
- if (!scsi_device_online(sdp))
+ if (!sdp || !scsi_device_online(sdp))
goto out;

buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
--
1.7.9

2012-02-14 04:13:40

by Yang Bai

Subject: Re: [PATCH] scsi: if sd card is removed, do not revalidate it

On Tue, Feb 14, 2012 at 12:10 PM, Yang Bai <[email protected]> wrote:
> During revalidating, if sd card is removed, scsi_device
> will be NULL, so we should not revalidate or it will cause
> a panic.
> This problem is report at:
> http://comments.gmane.org/gmane.linux.kernel/1250235
>
> Signed-off-by: Yang Bai <[email protected]>
> ---
>  drivers/scsi/sd.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index c691fb5..470339c 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -2370,10 +2370,10 @@ static int sd_revalidate_disk(struct gendisk *disk)
>                                      "sd_revalidate_disk\n"));
>
>        /*
> -        * If the device is offline, don't try and read capacity or any
> +        * If the device is removed or offline, don't try and read capacity or any
>         * of the other niceties.
>         */
> -       if (!scsi_device_online(sdp))
> +       if (!sdp || !scsi_device_online(sdp))
>                goto out;
>
>        buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
> --
> 1.7.9
>

Is this the right way to solve this problem? Or should we add
a lock to this struct to protect it?

--
    """
    Keep It Simple,Stupid.
    """

Chinese Name: 白杨
Nick Name: Hamo
Homepage: http://hamobai.com/
GPG KEY ID: 0xA4691A33
Key fingerprint = 09D5 2D78 8E2B 0995 CF8E  4331 33C4 3D24 A469 1A33