__get_user_pages_fast try to walk the page table but the hugepage pte is replace by hwpoison swap entry by mca path. ... [15798.177437] mce: Uncorrected hardware memory error in user-access at 224f1761c0 [15798.180171] MCE 0x224f176: Killing pal_main:6784 due to hardware memory corruption [15798.180176] MCE 0x224f176: Killing qemu-system-x86:167336 due to hardware memory corruption ... [15798.180206] BUG: unable to handle kernel [15798.180226] paging request at ffff891200003000 [15798.180236] IP: [<ffffffff8106edae>] gup_pud_range+ 0x13e/0x1e0 ... We need to skip the hwpoison entry in gup_pud_range. Signed-off-by: Qiujun Huang <hqjagain@xxxxxxxxx> --- mm/gup.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/gup.c b/mm/gup.c index 98f13ab..6157ed9 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2230,6 +2230,8 @@ static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end, next = pud_addr_end(addr, end); if (pud_none(pud)) return 0; + if (unlikely(!pud_present(pud))) + return 0; if (unlikely(pud_huge(pud))) { if (!gup_huge_pud(pud, pudp, addr, next, flags, pages, nr)) -- 1.8.3.1