On 2023/1/14 6:16, SeongJae Park wrote:
Hello,
On Fri, 13 Jan 2023 19:04:14 +0000 Lorenzo Stoakes <lstoakes@xxxxxxxxx> wrote:
On Fri, Jan 13, 2023 at 02:08:36PM +0100, David Hildenbrand wrote:
On 13.01.23 14:01, Marek Szyprowski wrote:
Hi
On 12.01.2023 09:30, Kefeng Wang wrote:
The old_page/new_page are converted to old_folio/new_folio in
wp_page_copy(), then replaced related page functions to folio
functions.
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
This patch, merged into today's linux-next as commit 9ebae00c8e30 ("mm:
memory: convert wp_page_copy() to use folios"), causes serious stability
issues on my ARM based test boards. Here is the example of such crash:
syzbot is also not happy:
https://lkml.kernel.org/r/000000000000807c7805f2205df1@xxxxxxxxxx
--
Thanks,
David / dhildenb
This also completely broke my qemu environment.
Same to me.
In that thread Willy points out that the issue stems from blindly assigning
page_folio(old_page) to old_folio without checking whether it is NULL first,
therefore triggering a NULL pointer deref.
A quick fix would be to put in a check (as shown below) which fixes the issue,
but as Willy said, I think we should drop this until it can be fixed in a
respin.
Hello all, sorry for the break, thanks all to quick fix and analysis, as
the patch has be dropped from mm-unstable and next, will resend after
address some comments from Matthew Wilcox and do more test.
