On 17/04/18 01:09, Maran Wilson wrote: > For certain applications it is desirable to rapidly boot a KVM virtual > machine. In cases where legacy hardware and software support within the > guest is not needed, Qemu should be able to boot directly into the > uncompressed Linux kernel binary without the need to run firmware. > > There already exists an ABI to allow this for Xen PVH guests and the ABI > is supported by Linux and FreeBSD: > > https://xenbits.xen.org/docs/unstable/misc/pvh.html > > This patch series would enable Qemu to use that same entry point for > booting KVM guests.
Hi Maran, what happened to this series (and to the QEMU work)? Paolo > Changes from v6: > > * Addressed issues caught by the kbuild test robot: > - Restored an #include line that had been dropped by mistake (patch 4) > - Removed a pair of #include lines that were no longer needed in a > common code file and causing problems for certain 32-bit configs > (patchs 4 and 7) > > Changes from v5: > > * The interface changes to the x86/HVM start info layout have > now been accepted into the Xen tree. > * Rebase and merge upstream PVH file changes. > * (Patch 6) Synced up to the final version of the header file that was > acked and pulled into the Xen tree. > * (Patch 1) Fixed typo and removed redundant "def_bool n" line. > > Changes from v4: > > Note: I've withheld Juergen's earlier "Reviewed-by" tags from patches > 1 and 7 since there were minor changes (mostly just addition of > CONFIG_KVM_GUEST_PVH as requested) that came afterwards. > > * Changed subject prefix from RFC to PATCH > * Added CONFIG_KVM_GUEST_PVH as suggested > * Relocated the PVH common files to > arch/x86/platform/pvh/{enlighten.c,head.S} > * Realized I also needed to move the objtool override for those files > * Updated a few code comments per reviewer feedback > * Sent out a patch of the hvm_start_info struct changes against the Xen > tree since that is the canonical copy of the header. Discussions on > that thread have resulted in some (non-functional) updates to > start_info.h (patch 6/7) and those changes are reflected here as well > in order to keep the files in sync. The header file has since been > ack'ed for the Xen tree by Jan Beulich. > > Changes from v3: > > * Implemented Juergen's suggestion for refactoring and moving the PVH > code so that CONFIG_XEN is no longer required for booting KVM guests > via the PVH entry point. > Functionally, nothing has changed from V3 really, but the patches > look completely different now because of all the code movement and > refactoring. Some of these patches can be combined, but I've left > them very small in some cases to make the refactoring and code > movement easier to review. > My approach for refactoring has been to create a PVH entry layer that > still has understanding and knowledge about Xen vs non-Xen guest types > so that it can make run time decisions to handle either case, as > opposed to going all the way and re-writing it to be a completely > hypervisor agnostic and architecturally pure layer that is separate > from guest type details. The latter seemed a bit overkill in this > situation. And I've handled the complexity of having to support > Qemu/KVM boot of kernels compiled with or without CONFIG_XEN via a > pair of xen specific __weak routines that can be overridden in kernels > that support Xen guests. Importantly, the __weak routines are for > xen specific code only (not generic "guest type" specific code) so > there is no clashing between xen version of the strong routine and, > say, a KVM version of the same routine. But I'm sure there are many > ways to skin this cat, so I'm open to alternate suggestions if there > is a compelling reason for not using __weak in this situation. > > Changes from v2: > > * All structures (including memory map table entries) are padded and > aligned to an 8 byte boundary. > > * Removed the "packed" attributes and made changes to comments as > suggested by Jan. > > Changes from v1: > > * Adopted Paolo's suggestion for defining a v2 PVH ABI that includes the > e820 map instead of using the second module entry to pass the table. > > * Cleaned things up a bit to reduce the number of xen vs non-xen special > cases. > > > Maran Wilson (7): > xen/pvh: Split CONFIG_XEN_PVH into CONFIG_PVH and CONFIG_XEN_PVH > xen/pvh: Move PVH entry code out of Xen specific tree > xen/pvh: Create a new file for Xen specific PVH code > xen/pvh: Move Xen specific PVH VM initialization out of common file > xen/pvh: Move Xen code for getting mem map via hcall out of common > file > xen/pvh: Add memory map pointer to hvm_start_info struct > KVM: x86: Allow Qemu/KVM to use PVH entry point > > MAINTAINERS | 1 + > arch/x86/Kbuild | 2 + > arch/x86/Kconfig | 14 +++ > arch/x86/kernel/head_64.S | 2 +- > arch/x86/platform/pvh/Makefile | 5 + > arch/x86/platform/pvh/enlighten.c | 136 > ++++++++++++++++++++++++ > arch/x86/{xen/xen-pvh.S => platform/pvh/head.S} | 0 > arch/x86/xen/Kconfig | 3 +- > arch/x86/xen/Makefile | 2 - > arch/x86/xen/enlighten_pvh.c | 93 +++------------- > include/xen/interface/hvm/start_info.h | 63 ++++++++++- > 11 files changed, 240 insertions(+), 81 deletions(-) > create mode 100644 arch/x86/platform/pvh/Makefile > create mode 100644 arch/x86/platform/pvh/enlighten.c > rename arch/x86/{xen/xen-pvh.S => platform/pvh/head.S} (100%) > _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel