similar to: [PATCH v2 00/11] x86/paravirt: several cleanups

This series removes some no longer needed stuff from paravirt infrastructure and puts large quantities of paravirt ops under a new config option PARAVIRT_XXL which is selected by XEN_PV only. A pvops kernel without XEN_PV being configured is about 2.5% smaller with this series applied. tip commit 5800dc5c19f34e6e03b5adab1282535cb102fafd ("x86/paravirt: Fix spectre-v2 mitigations for

Today paravirtualization is a all-or-nothing game: either a kernel is compiled with no paravirtualization support at all, or it is supporting paravirtualized environments like Xen pv-guests or lguest additionally to some paravirtualized tuning for KVM, Hyperv, VMWare or Xen HVM-guests. As support of pv-guests requires quite intrusive pv-hooks (e.g. all access functions to page table entries,

Today paravirtualization is a all-or-nothing game: either a kernel is compiled with no paravirtualization support at all, or it is supporting paravirtualized environments like Xen pv-guests or lguest additionally to some paravirtualized tuning for KVM, Hyperv, VMWare or Xen HVM-guests. As support of pv-guests requires quite intrusive pv-hooks (e.g. all access functions to page table entries,

This changes the pv ops code generation to more closely match reality. For example, instead of: callq *0xffffffff81e3a400 (pv_irq_ops.save_fl) vmlinux will now show: pushfq pop %rax nop nop nop nop nop which is what the runtime version of the code will show in most cases. This idea was suggested by Andy Lutomirski. The benefits are: - For the most common runtime cases

This changes the pv ops code generation to more closely match reality. For example, instead of: callq *0xffffffff81e3a400 (pv_irq_ops.save_fl) vmlinux will now show: pushfq pop %rax nop nop nop nop nop which is what the runtime version of the code will show in most cases. This idea was suggested by Andy Lutomirski. The benefits are: - For the most common runtime cases

The first patch fixes Xen PV regression introduced by 32-bit rewrite. Unlike the earlier version it uses ALTERNATIVE instruction and avoids using xen_sysexit (and sysret32 in compat mode) pv ops, as suggested by Andy. (I ended up patching TEST with XOR to avoid extra NOPs, even though I said yesterday it would be wrong. It's not wrong) As result of this patch irq_enable_sysexit and

The first patch fixes Xen PV regression introduced by 32-bit rewrite. Unlike the earlier version it uses ALTERNATIVE instruction and avoids using xen_sysexit (and sysret32 in compat mode) pv ops, as suggested by Andy. (I ended up patching TEST with XOR to avoid extra NOPs, even though I said yesterday it would be wrong. It's not wrong) As result of this patch irq_enable_sysexit and

Hi folks, With this series, the bulk of the work of pvops64 is done. Here, I integrate most of the paravirt.c and paravirt.h files, making them applicable to both architectures. CONFIG_PARAVIRT is _not_ present yet. Basically, this code is missing page table integration (patches currently being worked on by Jeremy). Enjoy

Hi folks, With this series, the bulk of the work of pvops64 is done. Here, I integrate most of the paravirt.c and paravirt.h files, making them applicable to both architectures. CONFIG_PARAVIRT is _not_ present yet. Basically, this code is missing page table integration (patches currently being worked on by Jeremy). Enjoy

Hi Linus, Here's a set of patches to update paravirt_ops and Xen for 2.6.24 A quick overview of the patchset: paravirt_ops: Remove the monolithic paravirt_ops structure, and replace it with smaller structures of related functions. Also, clean up the handling of lazy mode to make it easier to implement. x86/mm/init.c: remove a chunk of dead code Xen: - remove duplicate includes -

Hi Linus, Here's a set of patches to update paravirt_ops and Xen for 2.6.24 A quick overview of the patchset: paravirt_ops: Remove the monolithic paravirt_ops structure, and replace it with smaller structures of related functions. Also, clean up the handling of lazy mode to make it easier to implement. x86/mm/init.c: remove a chunk of dead code Xen: - remove duplicate includes -

Hi Linus, Here's a set of patches to update paravirt_ops and Xen for 2.6.24 A quick overview of the patchset: paravirt_ops: Remove the monolithic paravirt_ops structure, and replace it with smaller structures of related functions. Also, clean up the handling of lazy mode to make it easier to implement. x86/mm/init.c: remove a chunk of dead code Xen: - remove duplicate includes -

The first patch fixes Xen PV regression introduced by 32-bit rewrite. Unlike the earlier version it uses ALTERNATIVE instruction and avoids using xen_sysexit (and sysret32 in compat mode) pv ops, as suggested by Andy. As result of this patch irq_enable_sysexit and usergs_sysret32 pv ops are not used anymore by anyone and so can be removed. v2: * patch both TEST and JZ intructions with a

The first patch fixes Xen PV regression introduced by 32-bit rewrite. Unlike the earlier version it uses ALTERNATIVE instruction and avoids using xen_sysexit (and sysret32 in compat mode) pv ops, as suggested by Andy. As result of this patch irq_enable_sysexit and usergs_sysret32 pv ops are not used anymore by anyone and so can be removed. v2: * patch both TEST and JZ intructions with a

The long term plan has been to replace Xen PV guests by PVH. The first victim of that plan are now 32-bit PV guests, as those are used only rather seldom these days. Xen on x86 requires 64-bit support and with Grub2 now supporting PVH officially since version 2.04 there is no need to keep 32-bit PV guest support alive in the Linux kernel. Additionally Meltdown mitigation is not available in the

The long term plan has been to replace Xen PV guests by PVH. The first victim of that plan are now 32-bit PV guests, as those are used only rather seldom these days. Xen on x86 requires 64-bit support and with Grub2 now supporting PVH officially since version 2.04 there is no need to keep 32-bit PV guest support alive in the Linux kernel. Additionally Meltdown mitigation is not available in the

Paravirt ops is currently only capable of either replacing a lot of Linux internal code or none at all. The are users that don't need all of the possibilities pv-ops delivers though. On KVM for example we're perfectly fine not using the PV MMU, thus not touching any MMU code. That way we don't have to improve pv-ops to become fast, we just don't compile the MMU parts in! This

Paravirt ops is currently only capable of either replacing a lot of Linux internal code or none at all. The are users that don't need all of the possibilities pv-ops delivers though. On KVM for example we're perfectly fine not using the PV MMU, thus not touching any MMU code. That way we don't have to improve pv-ops to become fast, we just don't compile the MMU parts in! This

Hi folks, Here is the result of the latest work on the pvops front, after the x86 arch merge. From the functionality point of view, almost nothing was changed, except for proper vsmp support - which was discussed, but not implemented before - and the introduction of smp_ops in x86_64, which eased the merging of the smp header. Speaking of the merge, a significant part (although not majority) of

Hi folks, Here is the result of the latest work on the pvops front, after the x86 arch merge. From the functionality point of view, almost nothing was changed, except for proper vsmp support - which was discussed, but not implemented before - and the introduction of smp_ops in x86_64, which eased the merging of the smp header. Speaking of the merge, a significant part (although not majority) of