From: Joerg Roedel <jroe...@suse.de>
The walk_pte_level() function just uses __va to get the
virtual address of the PTE page, but that breaks when
the PTE page is not in the direct mapping with HIGHPTE=y.
The result is an unhandled kernel paging request at some
random address when accessing the current_kernel or
current_user file.
Use the correct API to access PTE pages nd fix the oops.
Fixes: fe770bf0310d ('x86: clean up the page table dumper and add 32-bit
support')
Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
arch/x86/mm/dump_pagetables.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 956c886f5dff..db1d7a0e6335 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -18,6 +18,7 @@
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
+#include <linux/highmem.h>
#include <asm/pgtable.h>
@@ -344,16 +345,16 @@ static void walk_pte_level(struct seq_file *m, struct
pg_state *st, pmd_t addr,
pgprotval_t eff_in, unsigned long P)
{
int i;
- pte_t *start;
+ pte_t *pte;
pgprotval_t prot, eff;
- start = (pte_t *)pmd_page_vaddr(addr);
for (i = 0; i < PTRS_PER_PTE; i++) {
- prot = pte_flags(*start);
- eff = effective_prot(eff_in, prot);
st->current_address = normalize_addr(P + i * PTE_LEVEL_MULT);
+ pte = pte_offset_map(&addr, st->current_address);
+ prot = pte_flags(*pte);
+ eff = effective_prot(eff_in, prot);
note_page(m, st, __pgprot(prot), eff, 5);
- start++;
+ pte_unmap(pte);
}
}
#ifdef CONFIG_KASAN
--
2.13.6
