kexec: load-preserve-context option on s390

[Vivek Goyal]

On Thu, Sep 29, 2011 at 03:38:31PM +0200, Michael Holzheu wrote:
> Hello Vivec,

Right spelling is "Vivek" and not "Vivec" :-)

[..]
> > 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.
> 

Shouldn't following existing code take care of this already?

        /*
         * Verify we have a legal set of flags
         * This leaves us room for future extensions.
         */
        if ((flags & KEXEC_FLAGS) != (flags & ~KEXEC_ARCH_MASK))
                return -EINVAL;

In include/linux/kexec.h, we have following.

/* List of defined/legal kexec flags */
#ifndef CONFIG_KEXEC_JUMP
#define KEXEC_FLAGS    KEXEC_ON_CRASH
#else
#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
#endif

Not sure why it is not working.

Thanks
Vivek