diff options
| author | Lepton Wu <ytht.net@gmail.com> | 2018-01-16 15:19:14 +0100 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2018-02-13 18:32:24 +0000 |
| commit | d663ef5a8632389b31c629ac14485ca6f50a7f5e (patch) | |
| tree | 17b5c5b5dd4a77f00d6c0e61019bc911293d4b17 | |
| parent | 6d86843a11140f0816f3aeeeb01495e0f8e17b12 (diff) | |
kaiser: Set _PAGE_NX only if supported
This finally resolve crash if loaded under qemu + haxm. Haitao Shan pointed
out that the reason of that crash is that NX bit get set for page tables.
It seems we missed checking if _PAGE_NX is supported in kaiser_add_user_map
Link: https://www.spinics.net/lists/kernel/msg2689835.html
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Lepton Wu <ytht.net@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(backported from Greg K-H's 4.4 stable-queue)
Signed-off-by: Juerg Haefliger <juerg.haefliger@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | arch/x86/mm/kaiser.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/mm/kaiser.c b/arch/x86/mm/kaiser.c index 8c95caecd330..b6c645ec4906 100644 --- a/arch/x86/mm/kaiser.c +++ b/arch/x86/mm/kaiser.c @@ -189,6 +189,8 @@ static int kaiser_add_user_map(const void *__start_addr, unsigned long size, * requires that not to be #defined to 0): so mask it off here. */ flags &= ~_PAGE_GLOBAL; + if (!(__supported_pte_mask & _PAGE_NX)) + flags &= ~_PAGE_NX; if (flags & _PAGE_USER) BUG_ON(address < FIXADDR_START || end_addr >= FIXADDR_TOP); |