On 2023/2/1 8:32, Andrew Morton wrote:
On Tue, 13 Dec 2022 20:05:23 +0800 Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
When the kernel copy a page from ksm_might_need_to_copy(), but runs
into an uncorrectable error, it will crash since poisoned page is
consumed by kernel, this is similar to Copy-on-write poison recovery,
When an error is detected during the page copy, return VM_FAULT_HWPOISON
in do_swap_page(), and install a hwpoison entry in unuse_pte() when
swapoff, which help us to avoid system crash. Note, memory failure on
a KSM page will be skipped, but still call memory_failure_queue() to
be consistent with general memory failure process.
I believe we're awaiting a v4 of this?
Sorry, forget this one.
Did we consider a -stable backport? "kernel crash" sounds undesirable...
This one depends on Copy-on-write poison recovery patchset, and I check
the commit a873dfe1032a ("mm, hwpoison: try to recover from copy-on
write faults") is not included into stable, and both of them are
enhancement of COPY_MC feature, so it seems that we don't need to
backport to stable.
Can we identify a Fixes: target for this?
As it is a part of COPY_MC, I don't think it is need a Fixes tag.
I will resend a new one to address the comments of HORIGUCHI NAOYA(堀口
直也).
Thanks.
