3.11.10.13 -stable review patch. If anyone has any objections, please let me know.
------------------ From: "H. Peter Anvin" <h...@linux.intel.com> commit 246f2d2ee1d715e1077fc47d61c394569c8ee692 upstream. It is not safe to use LAR to filter when to go down the espfix path, because the LDT is per-process (rather than per-thread) and another thread might change the descriptors behind our back. Fortunately it is always *safe* (if a bit slow) to go down the espfix path, and a 32-bit LDT stack segment is extremely rare. Signed-off-by: H. Peter Anvin <h...@linux.intel.com> Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-...@linux.intel.com Signed-off-by: Luis Henriques <luis.henriq...@canonical.com> --- arch/x86/kernel/entry_32.S | 5 ----- 1 file changed, 5 deletions(-) diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index bbc89cf397bd..473f125a3a52 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -554,11 +554,6 @@ ENTRY(iret_exc) CFI_RESTORE_STATE ldt_ss: - larl PT_OLDSS(%esp), %eax - jnz restore_nocheck - testl $0x00400000, %eax # returning to 32bit stack? - jnz restore_nocheck # allright, normal return - #ifdef CONFIG_PARAVIRT /* * The kernel can't run on a non-flat stack if paravirt mode -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
