diff options
| author | Thomas Gleixner <[email protected]> | 2017-12-16 01:14:39 +0100 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2017-12-22 20:13:00 +0100 |
| commit | c05344947b37f7cda726e802457370bc6eac4d26 (patch) | |
| tree | a732c27364c81fb573588442da9539ffa464e87b | |
| parent | 7bbcbd3d1cdcbacd0f9f8dc4c98d550972f1ca30 (diff) | |
x86/mm/dump_pagetables: Check PAGE_PRESENT for real
The check for a present page in printk_prot():
if (!pgprot_val(prot)) {
/* Not present */
is bogus. If a PTE is set to PAGE_NONE then the pgprot_val is not zero and
the entry is decoded in bogus ways, e.g. as RX GLB. That is confusing when
analyzing mapping correctness. Check for the present bit to make an
informed decision.
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/mm/dump_pagetables.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index 5e3ac6fe6c9e..1014cfb21c2c 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -140,7 +140,7 @@ static void printk_prot(struct seq_file *m, pgprot_t prot, int level, bool dmsg) static const char * const level_name[] = { "cr3", "pgd", "p4d", "pud", "pmd", "pte" }; - if (!pgprot_val(prot)) { + if (!(pr & _PAGE_PRESENT)) { /* Not present */ pt_dump_cont_printf(m, dmsg, " "); } else { |