On Wed, Mar 14, 2012 at 11:21:37AM +0000, Alan Cox wrote: > You can use set_memory_x() to mark memory executable (and _nx to set it back). > NO I can't, if I set_memory_x and don't set pcibios_enabled = 1, then static_protections will still failed because pcibios_enabled == 0, and I don't want to use set_memory_x, because I don't want to give the user of uvesafb that feeling "I will lost BIOS NX protection if I choice uvesafb." > If you really need to know if NX is being used then the check > > if (__supported_pte_mask & PTE_NX) > > will do the trick and the variable is exported. I don't understand what do you mean, do you means CONFIG_X86_PAE for 32? Or CONFIG_X86_64? when NX is being used, the pci bios is NX or not also depend on ACPI.ACPI on or off all will influnce the code path in pci_arch_init, decide the set_bios_x have chance to execute or not.See https://lkml.org/lkml/2011/11/16/84 By the way _PAGE_NX instead of PTE_NX, right? > I'd suggest however you wrap that in a cpu_has_nx() type macro somewhere > in the arch headers. > The same above. > If you go poking around pcibios values you are going to get burned if > someone is ever bored enough to make NX and PCIBIOS work together > differently. > Indeed according to 5bd5a452662bc37c54fb6828db1a3faf87e6511c, who bring me the trouble, check the pcibios_enabled is the only simple and good way to resolve the Oops I meet. If you really don't want it, and if I am not all wrong about your "helper method", you means you want export the below: int check_pcibios_enabled()? See https://lkml.org/lkml/2012/2/26/124 Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html