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Message-ID: <2482854e18365087266c2f0907c1bbfd42bd2731.camel@linux.ibm.com>
Subject: Re: [PATCH] scsi: megaraid_mbox: return -ENOMEM on
 megaraid_init_mbox() allocation failure
From:   James Bottomley <jejb@linux.ibm.com>
Reply-To: jejb@linux.ibm.com
To:     Jiapeng Chong <jiapeng.chong@linux.alibaba.com>,
        kashyap.desai@broadcom.com
Cc:     sumit.saxena@broadcom.com, shivasharan.srikanteshwara@broadcom.com,
        martin.petersen@oracle.com, megaraidlinux.pdl@broadcom.com,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Tue, 19 Oct 2021 07:44:08 -0400
In-Reply-To: <1634640800-22502-1-git-send-email-jiapeng.chong@linux.alibaba.com>
References: <1634640800-22502-1-git-send-email-jiapeng.chong@linux.alibaba.com>
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On Tue, 2021-10-19 at 18:53 +0800, Jiapeng Chong wrote:
> From: chongjiapeng <jiapeng.chong@linux.alibaba.com>
> 
> Fixes the following smatch warning:
> 
> drivers/scsi/megaraid/megaraid_mbox.c:715 megaraid_init_mbox() warn:
> returning -1 instead of -ENOMEM is sloppy.

Why is this a problem?  megaraid_init_mbox() is called using this
pattern:

	// Start the mailbox based controller
	if (megaraid_init_mbox(adapter) != 0) {
		con_log(CL_ANN, (KERN_WARNING
			"megaraid: mailbox adapter did not initialize\n"));

		goto out_free_adapter;
	}

So the only meaningful returns are 0 on success and anything else
(although megaraid uses -1 for this) on failure.   Since -1 is the
conventional failure return, why alter that to something different that
still won't be printed or acted on?  And worse still, if we make this
change, it will likely excite other static checkers to complain we're
losing error information ...

James