[RFC PATCH] arm64: use non-global mappings for UEFI runtime regions
catalin.marinas at arm.com
Wed Nov 18 01:43:04 PST 2015
On Tue, Nov 17, 2015 at 09:53:31AM +0100, Ard Biesheuvel wrote:
> As pointed out by Russell King in response to the proposed ARM version
> of this code, the sequence to switch between the UEFI runtime mapping
> and current's actual userland mapping (and vice versa) is potentially
> unsafe, since it leaves a time window between the switch to the new
> page tables and the TLB flush where speculative accesses may hit on
> stale global TLB entries.
> So instead, use non-global mappings, and perform the switch via the
> ordinary ASID-aware context switch routines.
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
> arch/arm64/include/asm/mmu_context.h | 2 +-
> arch/arm64/kernel/efi.c | 14 +++++---------
> 2 files changed, 6 insertions(+), 10 deletions(-)
Patch applied. Thanks.
More information about the linux-arm-kernel