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Date:   Thu, 10 Nov 2022 14:30:26 -0500
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Subject: Re: [PATCH v2 1/2] x86: Check return values from early_memremap calls
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To:     Dave Hansen <dave.hansen@intel.com>, linux-kernel@vger.kernel.org,
        x86@kernel.org
Cc:     dpsmith@apertussolutions.com, tglx@linutronix.de, mingo@redhat.com,
        bp@alien8.de, hpa@zytor.com, luto@amacapital.net,
        dave.hansen@linux.intel.com, kanth.ghatraju@oracle.com,
        trenchboot-devel@googlegroups.com, jailhouse-dev@googlegroups.com,
        jan.kiszka@siemens.com, xen-devel@lists.xenproject.org,
        jgross@suse.com, boris.ostrovsky@oracle.com,
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References: <20221110154521.613472-1-ross.philipson@oracle.com>
 <20221110154521.613472-2-ross.philipson@oracle.com>
 <8e62a029-f2fa-0627-1f71-4850a68ec6b6@intel.com>
From:   Ross Philipson <ross.philipson@oracle.com>
In-Reply-To: <8e62a029-f2fa-0627-1f71-4850a68ec6b6@intel.com>
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On 11/10/22 11:07, Dave Hansen wrote:
> On 11/10/22 07:45, Ross Philipson wrote:
>>   	dt = early_memremap(initial_dtb, map_len);
>> +	if (!dt) {
>> +		pr_warn("failed to memremap initial dtb\n");
>> +		return;
>> +	}
> 
> Are all of these new pr_warn/err()'s really adding much value?  They all
> look pretty generic.  It makes me wonder if we should just spit out a
> generic message in early_memremap() and save all the callers the trouble.

These changes were prompted by some comments on an earlier patch set I 
sent. It was requested that I fix the other missing checks for NULL 
returns from these functions but I thought that was out of scope for 
that patch set. So I agreed to submit this set and add the checks making 
things consistent.

> 
> Oh, and don't we try to refer to functions() with parenthesis?

Yes I can fix that.

Thanks
Ross

>