[PATCH v2] Documentation: add 'crashkernel=auto' entry into kernel-parameters.txt

[Yaowei Bai <bywxiaobai@163.com>]

There is no 'crashkernel=auto' entry in kernel-parameters.txt, borrow it
from kexec-kdump-howto.txt file in the kexec-tools-2.0.0 package.

Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
---
 Documentation/kernel-parameters.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 1d6f045..9e5913e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -797,6 +797,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			It will be ignored when crashkernel=X,high is not used
 			or memory reserved is below 4G.
 
+	crashkernel=auto
+			This specification allows the kernel to decide how much
+			memory to reserve for the purposes of kdump. It will make
+			this determination based on the amount of memory you have
+			in your system, and scale the allocation accordingly.
+			Note that if you have less than 4Gb of memory in your system,
+			this specification will opt to not allocate any memory for
+			the purposes of kdump.
+
 	cs89x0_dma=	[HW,NET]
 			Format: <dma>
 
-- 
1.9.1