[PATCH v20 13/14] arm64: kdump: update a kernel doc

[Baoquan He]

On 07/01/16 at 04:37pm, AKASHI Takahiro wrote:
> Dave, Boaquan,
> 
> Thank you for your reviewing.
> 
> On Thu, Jun 30, 2016 at 05:00:45PM +0800, Baoquan He wrote:
> > On 06/23/16 at 05:54pm, Geoff Levand wrote:
> > > From: AKASHI Takahiro <takahiro.akashi at linaro.org>
> > > 
> > > This patch adds arch specific descriptions about kdump usage on arm64
> > > to kdump.txt.
> > > 
> > > Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> > > ---
> > >  Documentation/kdump/kdump.txt | 15 ++++++++++++++-
> > >  1 file changed, 14 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/Documentation/kdump/kdump.txt b/Documentation/kdump/kdump.txt
> > > index 88ff63d..5d6da09 100644
> > > --- a/Documentation/kdump/kdump.txt
> > > +++ b/Documentation/kdump/kdump.txt
> > > @@ -18,7 +18,7 @@ memory image to a dump file on the local disk, or across the network to
> > >  a remote system.
> > >  
> > >  Kdump and kexec are currently supported on the x86, x86_64, ppc64, ia64,
> > > -s390x and arm architectures.
> > > +s390x, arm and arm64 architectures.
> > >  
> > >  When the system kernel boots, it reserves a small section of memory for
> > >  the dump-capture kernel. This ensures that ongoing Direct Memory Access
> > > @@ -249,6 +249,12 @@ Dump-capture kernel config options (Arch Dependent, arm)
> > >  
> > >      AUTO_ZRELADDR=y
> > >  
> > > +Dump-capture kernel config options (Arch Dependent, arm64)
> > > +----------------------------------------------------------
> > > +
> > > +1) Currently, kvm will not be enabled on the dump-capture kernel even
> > > +   if it is configured.

And here, could you say more about it?

> > > +
> > >  Extended crashkernel syntax
> > >  ===========================
> > >  
> > > @@ -305,6 +311,8 @@ Boot into System Kernel
> > >     kernel will automatically locate the crash kernel image within the
> > >     first 512MB of RAM if X is not given.
> > >  
> > > +   On arm64, use "crashkernel=Y[@X]".  Note that the start address of
> > 				  ~ Why square brackets here, is it
> > different than other arch?
> 
> I want to clearly indicate that "@X" is optional, and that, when you explicitly
> specify it, X must be properly aligned.
> I think that "[..]" notation is quite common.

Yes, I see that. Just that has been noted in "Extended crashkernel
syntax" section, and adding "[]" is not consistent with other places
where "crashkernel=Y at X" is referred to in this section. Just feel it's
a little redundent. Anyway it's not very critical, and Dave has acked
it, I am fine if you want to keep it.

Thanks
Baoquan

> 
> Thanks,
> -Takahiro AKASHI
> 
> > 
> > Except for this, it looks good to me.
> > 
> > Thanks
> > Baoquan
> > 
> > > +   the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000).
> > >  
> > >  Load the Dump-capture Kernel
> > >  ============================
> > > @@ -327,6 +335,8 @@ For s390x:
> > >  	- Use image or bzImage
> > >  For arm:
> > >  	- Use zImage
> > > +For arm64:
> > > +	- Use vmlinux or Image
> > >  
> > >  If you are using a uncompressed vmlinux image then use following command
> > >  to load dump-capture kernel.
> > > @@ -370,6 +380,9 @@ For s390x:
> > >  For arm:
> > >  	"1 maxcpus=1 reset_devices"
> > >  
> > > +For arm64:
> > > +	"1 maxcpus=1 reset_devices"
> > > +
> > >  Notes on loading the dump-capture kernel:
> > >  
> > >  * By default, the ELF headers are stored in ELF64 format to support
> > > -- 
> > > 2.5.0
> > > 
> > > 
> > > 
> > > _______________________________________________
> > > kexec mailing list
> > > kexec at lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/kexec