[PATCH] kexec: Provide an option to use new kexec system call

[Vivek Goyal]

On Thu, Aug 14, 2014 at 10:46:29AM +0800, Baoquan He wrote:
> On 08/13/14 at 11:06am, Vivek Goyal wrote:
> > +/* New file based kexec system call related code */
> > +static int do_kexec_file_load(int fileind, int argc, char **argv,
> > +			unsigned long flags) {
> > +
> > +	char *kernel;
> 
> ........
> 
> > +	kernel_fd = open(kernel, O_RDONLY);
> > +	if (kernel_fd == -1) {
> > +		fprintf(stderr, "Failed to open file %s:%s\n", kernel,
> > +				strerror(errno));
> > +		return -1;
> > +	}
> > +
> > +	/* slurp in the input kernel */
> > +	kernel_buf = slurp_decompress_file(kernel, &kernel_size);
> > +
> > +	for (i = 0; i < file_types; i++) {
> > +		if (file_type[i].probe(kernel_buf, kernel_size) >= 0)
> > +			break;
> > +	}
> > +
> > +	if (i == file_types) {
> > +		fprintf(stderr, "Cannot determine the file type " "of %s\n",
> > +				kernel);
> > +		return -1;
> > +	}
> > +
> > +	ret = file_type[i].load(argc, argv, kernel_buf, kernel_size, &info);
> > +	if (ret < 0) {
> > +		fprintf(stderr, "Cannot load %s\n", kernel);
> > +		return ret;
> > +	}
> > +
> > +	if (!is_kexec_file_load_implemented()) {
> 
> Hi Vivek,
> 
> Can we put this check earlier, maybe before kernel file openning? Since
> if this syscall is not implemented, we don't have to do the opening or
> loading things.
> 

Ok, will do it.

Thanks
Vivek