kexec: load-preserve-context option on s390
holzheu at linux.vnet.ibm.com
Thu Sep 29 09:38:31 EDT 2011
On Thu, 2011-09-29 at 09:32 -0400, Vivek Goyal wrote:
> On Thu, Sep 29, 2011 at 08:51:02AM +0900, Simon Horman wrote:
> > On Mon, Sep 26, 2011 at 03:09:09PM +0200, Michael Holzheu wrote:
> > > Hello Simon,
> > >
> > > I think the --load-preserve-context and --load-jump-back-helper kexec
> > > options are not working on s390 because we do not support
> > > CONFIG_KEXEC_JUMP. I assume the same is true also on other
> > > architectures. Correct me, if I am wrong. Unfortunately I did not find
> > > much documentation for that feature.
> > >
> > > Wouldn't it be better to print an error message when the options are
> > > used on those architectures?
> > Ideally it would be nice if kexec-tools could ask the kernel
> > if KEXEC_JUMP is supported (or enabled?) or not rather than
> > hardcoding this information into kexec-tools on a per-architecture basis.
> Shouldn't kexec system call return error if KEXEC_JUMP is not supported
> and user asked for it?
I think currently not. I assume that we should check the
KEXEC_PRESERVE_CONTEXT flag in the kexec_load system call.
What about the following:
kernel/kexec.c | 4 ++++
1 file changed, 4 insertions(+)
@@ -949,6 +949,10 @@ SYSCALL_DEFINE4(kexec_load, unsigned lon
+ if (flags & KEXEC_PRESERVE_CONTEXT)
+ return -EOPNOTSUPP;
* Verify we have a legal set of flags
* This leaves us room for future extensions.
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