From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ben Hutchings <bhutchings@solarflare.com>
Subject: Re: [PATCH v6 04/10] ipc: add new SHM_SET command for sys_shmctl()
 call
Date: Mon, 15 Oct 2012 20:00:28 +0100
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Cc: <akpm@linux-foundation.org>, <catalin.marinas@arm.com>,
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To: Stanislav Kinsbursky <skinsbursky@parallels.com>
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On Mon, 2012-10-15 at 19:59 +0400, Stanislav Kinsbursky wrote:
> New SHM_SET command will be interpreted exactly as IPC_SET, but also will
> update key, cuid and cgid values. IOW, it allows to change existent key value.
> The fact, that key is not used is checked before update. Otherwise -EEXIST is
> returned.
[...]
> --- a/ipc/shm.c
> +++ b/ipc/shm.c
[...]
> @@ -759,6 +763,10 @@ static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
>  	case IPC_RMID:
>  		do_shm_rmid(ns, ipcp);
>  		goto out_up;
> +	case SHM_SET:
> +		err = ipc_update_key(&shm_ids(ns), &shmid64.shm_perm, ipcp);
> +		if (err)
> +			break;
[...]

Please add /* fall through */ here, and in the similar cases in patches
5 and 7, to make clear that it's deliberate.

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.