From: Joerg Roedel <[email protected]> When we have a 4-level page-table there is no p4d, so we map the pud in the pgd. The old code before commit fb43d6cb91ef already did that.
With the change from above commit we end up with an invalid page-table which causes undefined behavior. In one report it caused triple faults. Fix it by changing the p4d back to pud so that we have a correct page-table. Reported-by: Borislav Petkov <[email protected]> Fixes: fb43d6cb91ef ('x86/mm: Do not auto-massage page protections') Tested-by: Michal Kubecek <[email protected]> Tested-by: Borislav Petkov <[email protected]> Signed-off-by: Joerg Roedel <[email protected]> --- arch/x86/power/hibernate_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c index 48b14b534897..ccf4a49bb065 100644 --- a/arch/x86/power/hibernate_64.c +++ b/arch/x86/power/hibernate_64.c @@ -98,7 +98,7 @@ static int set_up_temporary_text_mapping(pgd_t *pgd) set_pgd(pgd + pgd_index(restore_jump_address), new_pgd); } else { /* No p4d for 4-level paging: point the pgd to the pud page table */ - pgd_t new_pgd = __pgd(__pa(p4d) | pgprot_val(pgtable_prot)); + pgd_t new_pgd = __pgd(__pa(pud) | pgprot_val(pgtable_prot)); set_pgd(pgd + pgd_index(restore_jump_address), new_pgd); } -- 2.13.6
