| commit | f15f38b8231189e6fa19fefc4d1f8f57107a6de2 | [log] [tgz] |
|---|---|---|
| author | Marc Zyngier <marc.zyngier@arm.com> | Fri Aug 10 10:12:39 2018 +0100 |
| committer | Marc Zyngier <marc.zyngier@arm.com> | Fri Aug 10 10:12:39 2018 +0100 |
| tree | 5686e69b8d4006a8c1b41e051c685e27c0d0b2e7 | |
| parent | 3c4d9137eefecf273a520d392071ffc9df0a9a7a [diff] |
arm64: Trap WFI executed in userspace It recently came to light that userspace can execute WFI, and that the arm64 kernel doesn trap this event. This sounds rather benign, but the kernel should decide when it wants to wait for an interrupt, and not userspace. Let's trap WFI and immediately return after having skipped the instruction. This effectively makes WFI a rather expensive NOP. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>