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authorKefeng Wang <wangkefeng.wang@huawei.com>2024-09-06 10:42:00 +0800
committerAndrew Morton <akpm@linux-foundation.org>2024-09-17 01:07:00 -0700
commitaa549f923f5e037a459dcd588932db9abfa8c158 (patch)
tree80217bcc85f2d105f1b3eab21c2c6321b54a1854 /mm
parent99185c10d5d9214d0d0c8b7866660203e344ee3b (diff)
mm: support poison recovery from do_cow_fault()
Patch series "mm: hwpoison: two more poison recovery". One more CoW path to support poison recorvery in do_cow_fault(), and the last copy_user_highpage() user is replaced to copy_mc_user_highpage() from copy_present_page() during fork to support poison recorvery too. This patch (of 2): Like commit a873dfe1032a ("mm, hwpoison: try to recover from copy-on write faults"), there is another path which could crash because it does not have recovery code where poison is consumed by the kernel in do_cow_fault(), a crash calltrace shown below on old kernel, but it could be happened in the lastest mainline code, CPU: 7 PID: 3248 Comm: mpi Kdump: loaded Tainted: G OE 5.10.0 #1 pc : copy_page+0xc/0xbc lr : copy_user_highpage+0x50/0x9c Call trace: copy_page+0xc/0xbc do_cow_fault+0x118/0x2bc do_fault+0x40/0x1a4 handle_pte_fault+0x154/0x230 __handle_mm_fault+0x1a8/0x38c handle_mm_fault+0xf0/0x250 do_page_fault+0x184/0x454 do_translation_fault+0xac/0xd4 do_mem_abort+0x44/0xbc Fix it by using copy_mc_user_highpage() to handle this case and return VM_FAULT_HWPOISON for cow fault. [wangkefeng.wang@huawei.com: unlock/put vmf->page, per Miaohe] Link: https://lkml.kernel.org/r/20240910021541.234300-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20240906024201.1214712-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20240906024201.1214712-2-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jiaqi Yan <jiaqiyan@google.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/memory.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 42674c0748cb..64421ea5a403 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -5089,10 +5089,14 @@ static vm_fault_t do_cow_fault(struct vm_fault *vmf)
if (ret & VM_FAULT_DONE_COW)
return ret;
- copy_user_highpage(vmf->cow_page, vmf->page, vmf->address, vma);
+ if (copy_mc_user_highpage(vmf->cow_page, vmf->page, vmf->address, vma)) {
+ ret = VM_FAULT_HWPOISON;
+ goto unlock;
+ }
__folio_mark_uptodate(folio);
ret |= finish_fault(vmf);
+unlock:
unlock_page(vmf->page);
put_page(vmf->page);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))