From: David Hildenbrand <address@hidden>
Summarizing the issue:
1. Memory regions contain ram blocks with a different size, if the
size is not properly aligned. While memory regions can have an
unaligned size, ram blocks can't. This is true when creating
resizable memory region with an unaligned size.
2. When resizing a ram block/memory region, the size of the memory
region is set to the aligned size. The callback is called with
the aligned size. The unaligned piece is lost.
Because of the above, if ACPI blob length modifications happens
after the initial virt_acpi_build() call, and the changed blob
length is within the PAGE size boundary, then the revised size
is not seen by the firmware on Guest reboot.
Hence make sure callback is called if memory region size is changed,
irrespective of aligned or not.
Signed-off-by: David Hildenbrand <address@hidden>
[Shameer: added commit log]
Signed-off-by: Shameer Kolothum <address@hidden>
Reviewed-by: Igor Mammedov <address@hidden>
---
Please find previous discussion here,
https://patchwork.kernel.org/patch/11432375/#23216751
---
exec.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/exec.c b/exec.c
index de9d949902..2874bb5088 100644
--- a/exec.c
+++ b/exec.c
@@ -2074,11 +2074,23 @@ static int memory_try_enable_merging(void *addr, size_t
len)
*/
int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp)
{
+ const ram_addr_t unaligned_size = newsize;
+
assert(block);
newsize = HOST_PAGE_ALIGN(newsize);
if (block->used_length == newsize) {
+ /*
+ * We don't have to resize the ram block (which only knows aligned
+ * sizes), however, we have to notify if the unaligned size changed.
+ */
+ if (unaligned_size != memory_region_size(block->mr)) {
+ memory_region_set_size(block->mr, unaligned_size);
+ if (block->resized) {
+ block->resized(block->idstr, unaligned_size, block->host);
+ }
+ }
return 0;
}
@@ -2102,9 +2114,9 @@ int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp)
block->used_length = newsize;
cpu_physical_memory_set_dirty_range(block->offset, block->used_length,
DIRTY_CLIENTS_ALL);
- memory_region_set_size(block->mr, newsize);
+ memory_region_set_size(block->mr, unaligned_size);
if (block->resized) {
- block->resized(block->idstr, newsize, block->host);
+ block->resized(block->idstr, unaligned_size, block->host);
}
return 0;
}