Re: [PATCH] x86/crash: Update the stale comment in reserve_crashkernel()

[Xunlei Pang <xpang@redhat.com>]

On 12/22/2016 at 11:22 AM, Baoquan He wrote:
> On 12/15/16 at 11:30am, Xunlei Pang wrote:
>> CRASH_KERNEL_ADDR_MAX was missing for a long time, update it
>> with more detailed explanation.
>>
>> Cc: Robert LeBlanc <robert@leblancnet.us>
>> Cc: Baoquan He <bhe@redhat.com>
>> Signed-off-by: Xunlei Pang <xlpang@redhat.com>
>> ---
>>  arch/x86/kernel/setup.c | 5 ++++-
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
>> index 9c337b0..79ee507 100644
>> --- a/arch/x86/kernel/setup.c
>> +++ b/arch/x86/kernel/setup.c
>> @@ -575,7 +575,10 @@ static void __init reserve_crashkernel(void)
>>  	/* 0 means: find the address automatically */
>>  	if (crash_base <= 0) {
>>  		/*
>> -		 *  kexec want bzImage is below CRASH_KERNEL_ADDR_MAX
>> +		 * Set CRASH_ADDR_LOW_MAX upper bound for crash range
>> +		 * as old kexec-tools loads bzImage below that, unless
>> +		 * "size,high" or "size@offset"(nonzero offset, see the
>> +		 * else leg below) is specified.
> Yes, this is a good catch. It might be better to add comment only about
> this if branch. If you want to say more about the upper bounds, better

OK, how about the following change?
        /*
         * Set CRASH_ADDR_LOW_MAX upper bound for crash memory.
         * as old kexec-tools loads bzImage below that, unless
         * "crashkernel=size[KMG],high" is specified.
         */

> discuss with Robert LeBlanc to see if it can be detailed in kdump.txt.

Yes, this is independent of Robert's documentation patch.

>
> Also please CC to x86 maintainers, or akpm. They can help merge this.

OK, thanks!

Regards,
Xunlei