On Wed, Feb 09, 2011 at 07:15:45AM +0900, Simon Horman wrote:
> On Tue, Feb 08, 2011 at 05:20:36PM +0200, Ahmed S. Darwish wrote:
> >
> > diff --git a/kexec/arch/i386/kexec-bzImage.c b/kexec/arch/i386/kexec-bzImage.c
> > index 83d3a69..2312eb8 100644
> > --- a/kexec/arch/i386/kexec-bzImage.c
> > +++ b/kexec/arch/i386/kexec-bzImage.c
> > @@ -43,32 +43,32 @@ static const int probe_debug = 0;
> >
> > int bzImage_probe(const char *buf, off_t len)
> > {
> > - struct x86_linux_header header;
> > + const struct x86_linux_header *header;
> > if ((uintmax_t)len < (uintmax_t)sizeof(header)) {
> > return -1;
> > }
> > - memcpy(&header, buf, sizeof(header));
> > - if (memcmp(header.header_magic, "HdrS", 4) != 0) {
> > + header = (void *)buf;
>
> Perhaps casting to (struct x86_linux_header*) would read better?
>
I felt that '(const struct x86_linux_header *)' is a bit long, but it's
not a big deal. Attached is the same patch with that line modified:
==>
Don't wholeheartedly copy the 32-Kbytes bzImage header area to the stack,
just use a constant pointer instead.
Signed-off-by: Ahmed S. Darwish <darwish.07 at gmail.com>
---
diff --git a/kexec/arch/i386/kexec-bzImage.c b/kexec/arch/i386/kexec-bzImage.c
index 83d3a69..29e9165 100644
--- a/kexec/arch/i386/kexec-bzImage.c
+++ b/kexec/arch/i386/kexec-bzImage.c
@@ -43,32 +43,32 @@ static const int probe_debug = 0;
int bzImage_probe(const char *buf, off_t len)
{
- struct x86_linux_header header;
+ const struct x86_linux_header *header;
if ((uintmax_t)len < (uintmax_t)sizeof(header)) {
return -1;
}
- memcpy(&header, buf, sizeof(header));
- if (memcmp(header.header_magic, "HdrS", 4) != 0) {
+ header = (const struct x86_linux_header *)buf;
+ if (memcmp(header->header_magic, "HdrS", 4) != 0) {
if (probe_debug) {
fprintf(stderr, "Not a bzImage\n");
}
return -1;
}
- if (header.boot_sector_magic != 0xAA55) {
+ if (header->boot_sector_magic != 0xAA55) {
if (probe_debug) {
fprintf(stderr, "No x86 boot sector present\n");
}
/* No x86 boot sector present */
return -1;
}
- if (header.protocol_version < 0x0200) {
+ if (header->protocol_version < 0x0200) {
if (probe_debug) {
fprintf(stderr, "Must be at least protocol version 2.00\n");
}
/* Must be at least protocol version 2.00 */
return -1;
}
- if ((header.loadflags & 1) == 0) {
+ if ((header->loadflags & 1) == 0) {
if (probe_debug) {
fprintf(stderr, "zImage not a bzImage\n");
}
thanks,
--
Darwish
http://darwish.07.googlepages.com
