On Tue, 30 Mar 2021 at 10:47, Greg KH <gre...@linuxfoundation.org> wrote: > > On Tue, Mar 30, 2021 at 10:33:51AM -0600, Mathieu Poirier wrote: > > On Tue, 30 Mar 2021 at 09:35, Greg KH <gre...@linuxfoundation.org> wrote: > > > > > > On Tue, Mar 30, 2021 at 09:23:14AM -0600, Mathieu Poirier wrote: > > > > On Tue, Mar 30, 2021 at 11:38:18AM +0100, Suzuki K Poulose wrote: > > > > > On 26/03/2021 16:55, Mathieu Poirier wrote: > > > > > > On Tue, Mar 23, 2021 at 12:06:35PM +0000, Suzuki K Poulose wrote: > > > > > > > For a nvhe host, the EL2 must allow the EL1&0 translation > > > > > > > regime for TraceBuffer (MDCR_EL2.E2TB == 0b11). This must > > > > > > > be saved/restored over a trip to the guest. Also, before > > > > > > > entering the guest, we must flush any trace data if the > > > > > > > TRBE was enabled. And we must prohibit the generation > > > > > > > of trace while we are in EL1 by clearing the TRFCR_EL1. > > > > > > > > > > > > > > For vhe, the EL2 must prevent the EL1 access to the Trace > > > > > > > Buffer. > > > > > > > > > > > > > > Cc: Will Deacon <w...@kernel.org> > > > > > > > Cc: Catalin Marinas <catalin.mari...@arm.com> > > > > > > > Cc: Marc Zyngier <m...@kernel.org> > > > > > > > Cc: Mark Rutland <mark.rutl...@arm.com> > > > > > > > Cc: Anshuman Khandual <anshuman.khand...@arm.com> > > > > > > > Acked-by: Mathieu Poirier <mathieu.poir...@linaro.org> > > > > > > > Signed-off-by: Suzuki K Poulose <suzuki.poul...@arm.com> > > > > > > > --- > > > > > > > arch/arm64/include/asm/el2_setup.h | 13 +++++++++ > > > > > > > arch/arm64/include/asm/kvm_arm.h | 2 ++ > > > > > > > arch/arm64/include/asm/kvm_host.h | 2 ++ > > > > > > > arch/arm64/kernel/hyp-stub.S | 3 ++- > > > > > > > arch/arm64/kvm/debug.c | 6 ++--- > > > > > > > arch/arm64/kvm/hyp/nvhe/debug-sr.c | 42 > > > > > > > ++++++++++++++++++++++++++++++ > > > > > > > arch/arm64/kvm/hyp/nvhe/switch.c | 1 + > > > > > > > 7 files changed, 65 insertions(+), 4 deletions(-) > > > > > > > > > > > > > > > > > > > Marc - do you want me to pick up this one? > > > > > > > > > > I think the kvmarm tree is the best route for this patch, given the > > > > > amount > > > > > of changes the tree is going through, in the areas this patch > > > > > touches. Or else there would be conflicts with merging. And this patch > > > > > depends on the patches from this series that were queued. > > > > > > > > > > Here is the depency tree : > > > > > > > > > > a) kvm-arm fixes for debug (Patch 1, 2) & SPE save-restore fix > > > > > (queued in > > > > > v5.12-rc3) > > > > > > > > > > b) TRBE defintions and Trace synchronization barrier (Patches 5 & 6) > > > > > > > > > > c) kvm-arm TRBE host support (Patch 7) > > > > > > > > > > d) TRBE driver support (and the ETE changes) > > > > > > > > > > > > > > > (c) code merge depends on -> (a) + (b) > > > > > (d) build (no conflicts) depends on -> (b) > > > > > > > > > > > > > > > Now (d) has an indirect dependency on (c) for operational correctness > > > > > at > > > > > runtime. > > > > > So, if : > > > > > > > > > > kvmarm tree picks up : b + c > > > > > coresight tree picksup : b + d > > > > > > > > > > and if we could ensure the merge order of the trees are in > > > > > kvmarm > > > > > greg-kh (device-misc tree) (coresight goes via this tree) > > > > > > > > > > > > > Greg's char-misc tree is based on the rc releases rather than next. As > > > > such it > > > > is a while before other branches like kvmarm get merged, causing all > > > > sort of > > > > compilation breakage. > > > > > > My tree can not be based on -next, and neither can any other > > > maintainer's tree, as next is composed of maintainer trees :) > > > > > > > Exactly > > > > > > > we should be fine. > > > > > > > > > > Additionally, we could rip out the Kconfig changes from the TRBE patch > > > > > and add it only at the rc1, once we verify both the trees are in to > > > > > make > > > > > sure the runtime operation dependency is not triggered. > > > > > > > > > > > > > We could also do that but Greg might frown at the tactic, and rightly > > > > so. The > > > > usual way to work with complex merge dependencies is to proceed in > > > > steps, which > > > > would mean that all KVM related patches go in the v5.13 merge window. > > > > When that > > > > is done we add the ETE/TRBE for the v5.14 merge window. I agree that > > > > we waste > > > > an entire cycle but it guarantees to avoid breaking builds and follows > > > > the > > > > conventional way to do things. > > > > > > Or someone creates a single branch with a signed tag and it gets pulled > > > into multiple maintainer's trees and never rebased. We've done that > > > lots of time, nothing new there. Or everything goes through one tree, > > > or you wait a release cycle. > > > > > > You have 3 choices, pick one :) > > > > I'm perfectly happy with getting this entire set merged via Marc's > > kvmarm tree, as long as you are fine with it. > > No objection from me at all for this to go that way.
Swell - Marc, I'll send you a pull request. > > thanks, > > greg k-h
