| From | Andy Lutomirski <> | Date | Wed, 8 Mar 2017 07:54:51 -0800 | Subject | Re: [v6 PATCH 19/21] x86/traps: Fixup general protection faults caused by UMIP |
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On Tue, Mar 7, 2017 at 4:32 PM, Ricardo Neri <ricardo.neri-calderon@linux.intel.com> wrote: > If the User-Mode Instruction Prevention CPU feature is available and > enabled, a general protection fault will be issued if the instructions > sgdt, sldt, sidt, str or smsw are executed from user-mode context > (CPL > 0). If the fault was caused by any of the instructions protected > by UMIP, fixup_umip_exception will emulate dummy results for these > instructions. If emulation is successful, the result is passed to the > user space program and no SIGSEGV signal is emitted. > > Please note that fixup_umip_exception also caters for the case when > the fault originated while running in virtual-8086 mode.
Reviewed-by: Andy Lutomirski <luto@kernel.org>
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