Subject: Re: Fwd: [PATCH 1/1] of/fdt: failed to mark hotplug range message
To: Reza Arbab <arbab@linux.vnet.ibm.com>
References: <20161222053405.27190-1-xypron.glpk@gmx.de>
 <5251e7ef-cadf-7833-9a7e-66ebf78e2e94@gmx.de>
 <20161222214917.7g6ldgkdvrlqsyq3@arbab-laptop.austin.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>, Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
From: Heinrich Schuchardt <xypron.glpk@gmx.de>
Message-ID: <c0796a79-b30a-2e59-c36e-b9d2b4415d04@gmx.de>
Date: Thu, 22 Dec 2016 23:58:21 +0100
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On 12/22/2016 10:49 PM, Reza Arbab wrote:
> On Thu, Dec 22, 2016 at 06:52:45AM +0100, Heinrich Schuchardt wrote:
>> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
>> index c9b5cac03b36..fd129b6e5396 100644
>> --- a/drivers/of/fdt.c
>> +++ b/drivers/of/fdt.c
>> @@ -1057,7 +1057,7 @@ int __init early_init_dt_scan_memory(unsigned
>> long node, const char *uname,
>>
>>          if (early_init_dt_mark_hotplug_memory_arch(base, size))
>>              pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
>> -                base, base + size);
>> +                base, base + size - 1);
>>      }
>>
>>      return 0;
> 
> Isn't it implied that ranges printed this way are [start, end)?
> 
> If not, the entire file should be fixed, not just this occurrence.
> 
The output in the file drivers/of/fdt.c is currently inconsistent.
Alternative output formats are

pr_err("Reserved memory not supported, ignoring range %pa - %pa%s\n",
                  &base, &size, nomap ? " (nomap)" : "");

and

pr_debug("Reserved memory: reserved region for node '%s': base %pa, size
%ld MiB\n", uname, &base, (unsigned long)size / SZ_1M);

(Here we will see size = 0 for values less then 1 MiB.)

I expect intervals to be closed and not half open if not explicitly
indicated otherwise.

So I suggest we change all occurrences of interval output in
drivers/of/fdt.c to
0xfirstbyte - 0xlastbyte
where firstbyte = base and lastbyte = base + size - 1.

Using the %pa format code ensures that the length of the output matches
the bitness of address pointers in the system.

Best regards

Heinrich Schuchardt