The last version is "V4" and I added it in subject. On Fri, Jan 12, 2018 at 1:46 PM, Guenter Roeck <groeck@xxxxxxxxxx> wrote: > On Fri, Jan 12, 2018 at 1:41 PM, Lepton Wu <ytht.net@xxxxxxxxx> wrote: >> 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 >> >> Signed-off-by: Lepton Wu <ytht.net@xxxxxxxxx> > > Reviewed-by: Guenter Roeck <groeck@xxxxxxxxxxxx> > > Hint: You might want to version your patches; otherwise it is > difficult for the maintainer(s) to find the latest version. > > Note that the fix probably also applies to v4.9 as well as to older > stable kernels. > > Guenter > >> --- >> arch/x86/mm/kaiser.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/arch/x86/mm/kaiser.c b/arch/x86/mm/kaiser.c >> index 6a7a77929a8c..8af98513d36c 100644 >> --- a/arch/x86/mm/kaiser.c >> +++ b/arch/x86/mm/kaiser.c >> @@ -198,6 +198,8 @@ 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; >> >> for (; address < end_addr; address += PAGE_SIZE) { >> target_address = get_pa_from_mapping(address); >> -- >> 2.16.0.rc1.238.g530d649a79-goog >>