Re: [PATCH] cciss: Ignore stale commands after reboot

Jens Axboe
2009-07-02T19:00:55Z

On Thu, Jul 02 2009, Hannes Reinecke wrote:
>
> When doing an unexpected shutdown like kexec the cciss
> firmware might still have some commands in flight, which
> it is trying to complete.
> The driver is doing it's best on resetting the HBA,
> but sadly there's a firmware issue causing the firmware
> _not_ to abort or drop old commands.
> So the firmware will send us commands which we haven't
> accounted for, causing the driver to panic.
>
> With this patch we're just ignoring these commands as
> there is nothing we could be doing with them anyway.

Looks good to me. Mike, Stephen?

>
> Signed-off-by: Hannes Reinecke <hare@suse.de>
> ---
> drivers/block/cciss.c | 15 +++++++++++++--
> drivers/block/cciss_cmd.h | 1 +
> 2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
> index c7a527c..65a0655 100644
> --- a/drivers/block/cciss.c
> +++ b/drivers/block/cciss.c
> @@ -226,8 +226,18 @@ static inline void addQ(struct hlist_head *list, CommandList_struct *c)
>
> static inline void removeQ(CommandList_struct *c)
> {
> - if (WARN_ON(hlist_unhashed(&c->list)))
> + /*
> + * After kexec/dump some commands might still
> + * be in flight, which the firmware will try
> + * to complete. Resetting the firmware doesn't work
> + * with old fw revisions, so we have to mark
> + * them off as 'stale' to prevent the driver from
> + * falling over.
> + */
> + if (WARN_ON(hlist_unhashed(&c->list))) {
> + c->cmd_type = CMD_MSG_STALE;
> return;
> + }
>
> hlist_del_init(&c->list);
> }
> @@ -4246,7 +4256,8 @@ static void fail_all_cmds(unsigned long ctlr)
> while (!hlist_empty(&h->cmpQ)) {
> c = hlist_entry(h->cmpQ.first, CommandList_struct, list);
> removeQ(c);
> - c->err_info->CommandStatus = CMD_HARDWARE_ERR;
> + if (c->cmd_type != CMD_MSG_STALE)
> + c->err_info->CommandStatus = CMD_HARDWARE_ERR;
> if (c->cmd_type == CMD_RWREQ) {
> complete_command(h, c, 0);
> } else if (c->cmd_type == CMD_IOCTL_PEND)
> diff --git a/drivers/block/cciss_cmd.h b/drivers/block/cciss_cmd.h
> index cd665b0..dbaed1e 100644
> --- a/drivers/block/cciss_cmd.h
> +++ b/drivers/block/cciss_cmd.h
> @@ -274,6 +274,7 @@ typedef struct _ErrorInfo_struct {
> #define CMD_SCSI 0x03
> #define CMD_MSG_DONE 0x04
> #define CMD_MSG_TIMEOUT 0x05
> +#define CMD_MSG_STALE 0xff
>
> /* This structure needs to be divisible by 8 for new
> * indexing method.
> --
> 1.5.3.2
>

--
Jens Axboe