From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Fri, 19 Oct 2018 15:38:03 +0100 Subject: [PATCH] arm64: KVM: Guests can skip __install_bp_hardening_cb()s HYP work In-Reply-To: References: <20180921204919.5790-1-james.morse@arm.com> Message-ID: <20181019143803.GC3985@arrakis.emea.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Oct 19, 2018 at 11:17:32AM +0100, Marc Zyngier wrote: > On 21/09/18 21:49, James Morse wrote: > > enable_smccc_arch_workaround_1() passes NULL as the hyp_vecs start and > > end if the HVC conduit is in use, and ARM_SMCCC_ARCH_WORKAROUND_1 is > > detected. > > > > If the guest kernel happened to be built with KVM_INDIRECT_VECTORS, > > we go on to allocate a slot, memcpy() the empty workaround in and > > do the appropriate cache maintenance. > > > > This works as we always tell memcpy() the range is 0, so it never > > accesses the NULL src pointer, but we still do the cache maintenance. > > > > If hyp_vecs_start is NULL we know we're a guest, just update the fn > > like the !KVM_INDIRECT_VECTORS version. > > > > Signed-off-by: James Morse > > Reviewed-by: Julien Thierry > > Acked-by: Marc Zyngier > > Catalin: could you sneak this one in for 4.20? It is strictly a KVM > patch, but its location makes it more suitable for the arm64 tree... Done. -- Catalin