On Tue, Nov 1, 2022 at 3:28 AM TGSP tgsp002@gmail.com wrote:
From: xiongxin xiongxin@kylinos.cn
Added a check on the return value of preallocate_image_highmem(). If memory preallocate is insufficient, S4 cannot be done;
I am playing 4K video on a machine with AMD or other graphics card and only 8GiB memory, and the kernel is not configured with CONFIG_HIGHMEM. When doing the S4 test, the analysis found that when the pages get from minimum_image_size() is large enough, The preallocate_image_memory() and preallocate_image_highmem() calls failed to obtain enough memory. Add the judgment that memory preallocate is insufficient;
"pages -= free_unnecessary_pages()" below will let pages to drop a lot, so I wonder if it makes sense to add a judgment here.
Cc: stable@vger.kernel.org Signed-off-by: xiongxin xiongxin@kylinos.cn Signed-off-by: huanglei huanglei@kylinos.cn
kernel/power/snapshot.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index c20ca5fb9adc..670abf89cf31 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1738,6 +1738,7 @@ int hibernate_preallocate_memory(void) struct zone *zone; unsigned long saveable, size, max_size, count, highmem, pages = 0; unsigned long alloc, save_highmem, pages_highmem, avail_normal;
unsigned long size_highmem;
Please define this in the block where it will be used.
ktime_t start, stop; int error;@@ -1863,7 +1864,13 @@ int hibernate_preallocate_memory(void) pages_highmem += size;
The line above can be dropped.
alloc -= size; size = preallocate_image_memory(alloc, avail_normal);
pages_highmem += preallocate_image_highmem(alloc - size);
size_highmem += preallocate_image_highmem(alloc - size);
Did you mean "="?
Assuming you did, this could be
size_highmem = size + preallocate_image_highmem(alloc - size); if (size_highmem < alloc) {
if (size_highmem < (alloc - size)) {
The inner parens were not necessary.
pr_err("Image allocation is %lu pages short, exit\n",alloc - size - pages_highmem);goto err_out;}pages_highmem += size_highmem; pages += pages_highmem + size; }--
But overall it would be better to avoid bailing out.