Re: [PATCH] Reduce stack used by lib/hexdump.c

From: Jan Engelhardt <jengelh@computergmbh.de>
To: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Joe Perches <joe@perches.com>,
	linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Reduce stack used by lib/hexdump.c
Date: Thu, 29 Nov 2007 22:07:56 +0100 (CET)	[thread overview]
Message-ID: <Pine.LNX.4.64.0711292206450.3089@fbirervta.pbzchgretzou.qr> (raw)
In-Reply-To: <474F28EB.20608@oracle.com>

On Nov 29 2007 13:02, Randy Dunlap wrote:
>> @@ -140,13 +140,20 @@ EXPORT_SYMBOL(hex_dump_to_buffer);
>>   * Example output using %DUMP_PREFIX_ADDRESS and 4-byte mode:
>>   * ffffffff88089af0: 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.
>>   */
>> +
>> +#define HEX_LINE_SIZE 200
>> +
>>  void print_hex_dump(const char *level, const char *prefix_str, int
>>  prefix_type,
>>     int rowsize, int groupsize,
>>     const void *buf, size_t len, bool ascii)
>>  {
>>   const u8 *ptr = buf;
>>   int i, linelen, remaining = len;
>> -	unsigned char linebuf[200];
>> +	unsigned char *linebuf;
>> +
>> +	linebuf = kmalloc(HEX_LINE_SIZE, GFP_KERNEL);
>> +	if (!linebuf) {
>> +		WARN_ON(1);
>> +		return;
>> +	}
>>  

I'd add GFP_ATOMIC here. Who knows whether tomorrow, the oops dumper
or warn_on will use print_hex_dump.