Ah, ok. What I'm thinking of is something like the following (untested
and probably improperly thought out patch...):
--- orig/fs/proc/kcore.c Sat Nov 2 18:58:18 2002
+++ linux/fs/proc/kcore.c Fri Feb 7 19:48:35 2003
@@ -99,7 +99,10 @@
}
#else /* CONFIG_KCORE_AOUT */
+#ifndef KCORE_BASE
#define KCORE_BASE PAGE_OFFSET
+#define in_vmlist_region(x) ((x) >= VMALLOC_START && (x) < VMALLOC_END)
+#endif
#define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
@@ -394,7 +397,7 @@
tsz = buflen;
while (buflen) {
- if ((start >= VMALLOC_START) && (start < VMALLOC_END)) {
+ if (in_vmlist_region(start)) {
char * elf_buf;
struct vm_struct *m;
unsigned long curstart = start;
An architecture could then define KCORE_BASE and in_vmlist_region()
alongside their VMALLOC_START definition if they needed to change
them.
> There was some discussion on a better way to do this, by adding the
> kernel itself to the vmlist, and eliminating all the special case code.
> I took a brief look at this, but realised that there were all sorts
> of ugly race conditions with /proc/kcore if a module is loaded/unloaded
> after some process has read the Elf header.
Well, only root can debug using /proc/kcore, and I'd suggest the best
answer to that problem is "if it hurts, don't do that." I don't think
you should prevent modules from being unloaded just because you have
/proc/kcore open.
-- Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux http://www.arm.linux.org.uk/personal/aboutme.html- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/