The patch titled
powerpc: fix code for reserved memory spanning across nodes
has been added to the -mm tree. Its filename is
powerpc-fix-code-for-reserved-memory-spanning-across-nodes.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: powerpc: fix code for reserved memory spanning across nodes
From: Chandru <chandru@xxxxxxxxxx>
When booted with crashkernel=224M@32M or any memory size less than this,
the system boots properly. The following was the observation.. The
system comes up with two nodes (0-256M and 256M-4GB). The crashkernel
memory reservation spans across these two nodes. The
mark_reserved_regions_for_nid() in arch/powerpc/mm/numa.c resizes the
reserved part of the memory within it as:
if (end_pfn > node_ar.end_pfn)
reserve_size = (node_ar.end_pfn << PAGE_SHIFT)
- (start_pfn << PAGE_SHIFT);
but the reserve_bootmem_node() in mm/bootmem.c raises the pfn value of end
end = PFN_UP(physaddr + size);
This causes end to get a value past the last page in the 0-256M node.
Again when reserve_bootmem_node() returns,
mark_reserved_regions_for_nid() loops around to set the rest of the
crashkernel memory in the next node as reserved. It references
NODE_DATA(node_ar.nid) and this causes another 'Oops: kernel access of bad
area' problem. The following changes made the system to boot with any
amount of crashkernel memory size.
Signed-off-by: Chandru S <chandru@xxxxxxxxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/mm/numa.c | 7 ++++---
mm/bootmem.c | 4 ++++
2 files changed, 8 insertions(+), 3 deletions(-)
diff -puN arch/powerpc/mm/numa.c~powerpc-fix-code-for-reserved-memory-spanning-across-nodes arch/powerpc/mm/numa.c
--- a/arch/powerpc/mm/numa.c~powerpc-fix-code-for-reserved-memory-spanning-across-nodes
+++ a/arch/powerpc/mm/numa.c
@@ -995,10 +995,11 @@ void __init do_init_bootmem(void)
start_pfn, end_pfn);
free_bootmem_with_active_regions(nid, end_pfn);
+ }
+
+ for_each_online_node(nid) {
/*
- * Be very careful about moving this around. Future
- * calls to careful_allocation() depend on this getting
- * done correctly.
+ * Be very careful about moving this around.
*/
mark_reserved_regions_for_nid(nid);
sparse_memory_present_with_active_regions(nid);
diff -puN mm/bootmem.c~powerpc-fix-code-for-reserved-memory-spanning-across-nodes mm/bootmem.c
--- a/mm/bootmem.c~powerpc-fix-code-for-reserved-memory-spanning-across-nodes
+++ a/mm/bootmem.c
@@ -375,10 +375,14 @@ int __init reserve_bootmem_node(pg_data_
unsigned long size, int flags)
{
unsigned long start, end;
+ bootmem_data_t *bdata = pgdat->bdata;
start = PFN_DOWN(physaddr);
end = PFN_UP(physaddr + size);
+ if (end > bdata->node_low_pfn)
+ end = bdata->node_low_pfn;
+
return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
}
_
Patches currently in -mm which might be from chandru@xxxxxxxxxx are
powerpc-fix-code-for-reserved-memory-spanning-across-nodes.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
