提交 43297dda 编写于 作者: W Will Deacon 提交者: Marc Zyngier

KVM: arm64: add workaround for Cortex-A57 erratum #852523

When restoring the system register state for an AArch32 guest at EL2,
writes to DACR32_EL2 may not be correctly synchronised by Cortex-A57,
which can lead to the guest effectively running with junk in the DACR
and running into unexpected domain faults.

This patch works around the issue by re-ordering our restoration of the
AArch32 register aliases so that they happen before the AArch64 system
registers. Ensuring that the registers are restored in this order
guarantees that they will be correctly synchronised by the core.

Cc: <stable@vger.kernel.org>
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
上级 0c067292
......@@ -745,6 +745,9 @@ ENTRY(__kvm_vcpu_run)
// Guest context
add x2, x0, #VCPU_CONTEXT
// We must restore the 32-bit state before the sysregs, thanks
// to Cortex-A57 erratum #852523.
restore_guest_32bit_state
bl __restore_sysregs
skip_debug_state x3, 1f
......@@ -752,7 +755,6 @@ ENTRY(__kvm_vcpu_run)
kern_hyp_va x3
bl __restore_debug
1:
restore_guest_32bit_state
restore_guest_regs
// That's it, no more messing around.
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册