On 02/16/2012 09:52 PM, Dave Anderson wrote:
----- Original Message -----
...
So just do the same thing -- no verbose expanation is required.
There are two ways to fix this :
1) Fix dump_mem_map*() to print the header only when there is
information to dump.
--- a/memory.c
+++ b/memory.c
@@ -4637,13 +4637,6 @@ dump_mem_map_SPARSEMEM(struct meminfo *mi)
continue;
}
- if (print_hdr) {
- if (!(pc->curcmd_flags& HEADER_PRINTED))
- fprintf(fp, "%s", hdr);
- print_hdr = FALSE;
- pc->curcmd_flags |= HEADER_PRINTED;
- }
-
pp = section_mem_map_addr(section);
pp = sparse_decode_mem_map(pp, section_nr);
phys = (physaddr_t) section_nr * PAGES_PER_SECTION()
* PAGESIZE();
@@ -4854,6 +4847,13 @@ dump_mem_map_SPARSEMEM(struct meminfo *mi)
}
if (bufferindex> buffersize) {
+ if (print_hdr) {
+ if (!(pc->curcmd_flags& HEADER_PRINTED))
+ fprintf(fp, "%s", hdr);
+ print_hdr = FALSE;
+ pc->curcmd_flags |= HEADER_PRINTED;
+ }
+
fprintf(fp, "%s", outputbuffer);
bufferindex = 0;
}
@@ -4867,6 +4867,13 @@ dump_mem_map_SPARSEMEM(struct meminfo *mi)
}
if (bufferindex> 0) {
+ if (print_hdr) {
+ if (!(pc->curcmd_flags& HEADER_PRINTED))
+ fprintf(fp, "%s", hdr);
+ print_hdr = FALSE;
+ pc->curcmd_flags |= HEADER_PRINTED;
+ }
+
fprintf(fp, "%s", outputbuffer);
}
Similarly for the dump_mem_map().
2) Fix ppc_pgd_vtop() to return FALSE if the paddr> machdep->memsize
--- a/ppc.c
+++ b/ppc.c
@@ -438,6 +438,10 @@ ppc_pgd_vtop(ulong *pgd, ulong vaddr, physaddr_t
*paddr, int verbose)
*paddr = PAGEBASE(pte) + PAGEOFFSET(vaddr);
+ if (*paddr> machdep->memsize)
+ /* We don't have pages above System RAM */
+ return FALSE;
+
return TRUE;
no_page:
I prefer the (1). What do you think ?
Hi Suzuki,
Hmmm -- with respect to (1), I suppose that would work, although
given that both x86 and x86_64 pass through dump_mem_map_SPARSEMEM()
without printing the header in a non-existent-page case, I don't
understand why ppc is different?
Yep, I digged into that a little, but not deep enough to debug it with
a dump. Nothing was evident from the code :(.
And I'm thinking that a more general solution might be to change
do_vtop() here, and not even bother calling the relevant dump_mem_map()
function if there's no page struct associated with it:
--- memory.c 10 Feb 2012 16:41:38 -0000 1.273
+++ memory.c 16 Feb 2012 14:18:03 -0000
@@ -2796,7 +2796,7 @@
do_vtop(ulong vaddr, struct task_context *tc, ulong vtop_flags)
{
physaddr_t paddr;
- ulong vma;
+ ulong vma, pageptr;
int page_exists;
struct meminfo meminfo;
char buf1[BUFSIZE];
@@ -2930,7 +2930,7 @@
fprintf(fp, "\n");
- if (page_exists) {
+ if (page_exists&& phys_to_page(paddr,&pageptr)) {
if ((pc->flags& DEVMEM)&& (paddr>= VTOP(vt->high_memory)))
return;
BZERO(&meminfo, sizeof(struct meminfo));
And w/respect to (2), wouldn't that just cause the generic kvtop()
to fail? And if so, it kind of re-defines the meaning of kvtop(),
even though its current callers pretty much expect to receive
a legitimate physical memory address. But if a virtual address
resolves to a PTE with any legitimate address in it, then kvtop()
should return whatever's there.
Yep, I agree.
But I'm still wondering what makes ppc behave differently in
dump_mem_map_SPARSEMEM()?
Btw, we don't have SPARSMEM on ppc44x, and end up in dump_mem_map(). I was
patching both the functions to cover all the platforms.
Also, I found out that we need to abstract away the definition of Page flags
as well, since it differes for different platforms (except for the _PAGE_PRESENT).
I will include the changes in the next version.
Thanks
Suzuki
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