Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754632Ab2JVNp1 (ORCPT ); Mon, 22 Oct 2012 09:45:27 -0400 Received: from smtp.eu.citrix.com ([62.200.22.115]:5934 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753871Ab2JVNpX (ORCPT ); Mon, 22 Oct 2012 09:45:23 -0400 X-IronPort-AV: E=Sophos;i="4.80,629,1344211200"; d="scan'208";a="15310615" Date: Mon, 22 Oct 2012 14:44:40 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Konrad Rzeszutek Wilk CC: "linux-kernel@vger.kernel.org" , "xen-devel@lists.xensource.com" , "mukesh.rathor@oracle.com" , Ian Campbell , Stefano Stabellini Subject: Re: [PATCH 2/6] xen/pvh: Extend vcpu_guest_context, p2m, event, and xenbus to support PVH. In-Reply-To: <1350695882-12820-3-git-send-email-konrad.wilk@oracle.com> Message-ID: References: <1350695882-12820-1-git-send-email-konrad.wilk@oracle.com> <1350695882-12820-3-git-send-email-konrad.wilk@oracle.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8033 Lines: 215 On Sat, 20 Oct 2012, Konrad Rzeszutek Wilk wrote: > From: Mukesh Rathor > > make gdt_frames[]/gdt_ents into a union with {gdtaddr, gdtsz}, as PVH > only needs to send down gdtaddr and gdtsz. > > For interrupts, PVH uses native_irq_ops. > vcpu hotplug is currently not available for PVH. > > For events we follow what PVHVM does - to use callback vector. > Lastly, also use HVM path to setup XenBus. > > Signed-off-by: Mukesh Rathor > Signed-off-by: Konrad Rzeszutek Wilk > --- > arch/x86/include/asm/xen/interface.h | 11 +++++- > arch/x86/xen/irq.c | 5 ++- > arch/x86/xen/p2m.c | 2 +- > arch/x86/xen/smp.c | 75 ++++++++++++++++++++++------------ > drivers/xen/cpu_hotplug.c | 4 +- > drivers/xen/events.c | 9 ++++- > drivers/xen/xenbus/xenbus_client.c | 3 +- > 7 files changed, 77 insertions(+), 32 deletions(-) > > diff --git a/arch/x86/include/asm/xen/interface.h b/arch/x86/include/asm/xen/interface.h > index 6d2f75a..4c08f23 100644 > --- a/arch/x86/include/asm/xen/interface.h > +++ b/arch/x86/include/asm/xen/interface.h > @@ -144,7 +144,16 @@ struct vcpu_guest_context { > struct cpu_user_regs user_regs; /* User-level CPU registers */ > struct trap_info trap_ctxt[256]; /* Virtual IDT */ > unsigned long ldt_base, ldt_ents; /* LDT (linear address, # ents) */ > - unsigned long gdt_frames[16], gdt_ents; /* GDT (machine frames, # ents) */ > + union { > + struct { > + /* PV: GDT (machine frames, # ents).*/ > + unsigned long gdt_frames[16], gdt_ents; > + } pv; > + struct { > + /* PVH: GDTR addr and size */ > + unsigned long gdtaddr, gdtsz; > + } pvh; > + } u; > unsigned long kernel_ss, kernel_sp; /* Virtual TSS (only SS1/SP1) */ > /* NB. User pagetable on x86/64 is placed in ctrlreg[1]. */ > unsigned long ctrlreg[8]; /* CR0-CR7 (control registers) */ > diff --git a/arch/x86/xen/irq.c b/arch/x86/xen/irq.c > index 01a4dc0..fcbe56a 100644 > --- a/arch/x86/xen/irq.c > +++ b/arch/x86/xen/irq.c > @@ -5,6 +5,7 @@ > #include > #include > #include > +#include > #include > > #include > @@ -129,6 +130,8 @@ static const struct pv_irq_ops xen_irq_ops __initconst = { > > void __init xen_init_irq_ops(void) > { > - pv_irq_ops = xen_irq_ops; > + /* For PVH we use default pv_irq_ops settings */ > + if (!xen_feature(XENFEAT_hvm_callback_vector)) > + pv_irq_ops = xen_irq_ops; > x86_init.irqs.intr_init = xen_init_IRQ; > } > diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c > index 95fb2aa..ea553c8 100644 > --- a/arch/x86/xen/p2m.c > +++ b/arch/x86/xen/p2m.c > @@ -798,7 +798,7 @@ bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn) > { > unsigned topidx, mididx, idx; > > - if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) { > + if (xen_feature(XENFEAT_auto_translated_physmap)) { > BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY); > return true; > } > diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c > index 353c50f..df400349 100644 > --- a/arch/x86/xen/smp.c > +++ b/arch/x86/xen/smp.c > @@ -68,9 +68,11 @@ static void __cpuinit cpu_bringup(void) > touch_softlockup_watchdog(); > preempt_disable(); > > - xen_enable_sysenter(); > - xen_enable_syscall(); > - > + /* PVH runs in ring 0 and allows us to do native syscalls. Yay! */ > + if (!xen_feature(XENFEAT_supervisor_mode_kernel)) { > + xen_enable_sysenter(); > + xen_enable_syscall(); > + } > cpu = smp_processor_id(); > smp_store_cpu_info(cpu); > cpu_data(cpu).x86_max_cores = 1; > @@ -230,10 +232,11 @@ static void __init xen_smp_prepare_boot_cpu(void) > BUG_ON(smp_processor_id() != 0); > native_smp_prepare_boot_cpu(); > > - /* We've switched to the "real" per-cpu gdt, so make sure the > - old memory can be recycled */ > - make_lowmem_page_readwrite(xen_initial_gdt); > - > + if (!xen_feature(XENFEAT_writable_page_tables)) { > + /* We've switched to the "real" per-cpu gdt, so make sure the > + * old memory can be recycled */ > + make_lowmem_page_readwrite(xen_initial_gdt); > + } > xen_filter_cpu_maps(); > xen_setup_vcpu_info_placement(); > } > @@ -300,8 +303,6 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle) > gdt = get_cpu_gdt_table(cpu); > > ctxt->flags = VGCF_IN_KERNEL; > - ctxt->user_regs.ds = __USER_DS; > - ctxt->user_regs.es = __USER_DS; > ctxt->user_regs.ss = __KERNEL_DS; > #ifdef CONFIG_X86_32 > ctxt->user_regs.fs = __KERNEL_PERCPU; > @@ -310,35 +311,57 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle) > ctxt->gs_base_kernel = per_cpu_offset(cpu); > #endif > ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle; > - ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */ > > memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt)); > > - xen_copy_trap_info(ctxt->trap_ctxt); > + /* check for autoxlated to get it right for 32bit kernel */ I am not sure what this comment means, considering that in another comment below you say that we don't support 32bit PVH kernels. > + if (xen_feature(XENFEAT_auto_translated_physmap) && > + xen_feature(XENFEAT_supervisor_mode_kernel)) { > > - ctxt->ldt_ents = 0; > + ctxt->user_regs.ds = __KERNEL_DS; > + ctxt->user_regs.es = 0; > + ctxt->user_regs.gs = 0; > > - BUG_ON((unsigned long)gdt & ~PAGE_MASK); > + ctxt->u.pvh.gdtaddr = (unsigned long)gdt; > + ctxt->u.pvh.gdtsz = (unsigned long)(GDT_SIZE - 1); > > - gdt_mfn = arbitrary_virt_to_mfn(gdt); > - make_lowmem_page_readonly(gdt); > - make_lowmem_page_readonly(mfn_to_virt(gdt_mfn)); > +#ifdef CONFIG_X86_64 > + /* Note: PVH is not supported on x86_32. */ > + ctxt->gs_base_user = (unsigned long) > + per_cpu(irq_stack_union.gs_base, cpu); > +#endif > + } else { > + ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */ > + ctxt->user_regs.ds = __USER_DS; > + ctxt->user_regs.es = __USER_DS; > > - ctxt->gdt_frames[0] = gdt_mfn; > - ctxt->gdt_ents = GDT_ENTRIES; > + xen_copy_trap_info(ctxt->trap_ctxt); > > - ctxt->user_regs.cs = __KERNEL_CS; > - ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs); > + ctxt->ldt_ents = 0; > > - ctxt->kernel_ss = __KERNEL_DS; > - ctxt->kernel_sp = idle->thread.sp0; > + BUG_ON((unsigned long)gdt & ~PAGE_MASK); > + > + gdt_mfn = arbitrary_virt_to_mfn(gdt); > + make_lowmem_page_readonly(gdt); > + make_lowmem_page_readonly(mfn_to_virt(gdt_mfn)); > + > + ctxt->u.pv.gdt_frames[0] = gdt_mfn; > + ctxt->u.pv.gdt_ents = GDT_ENTRIES; > + > + ctxt->kernel_ss = __KERNEL_DS; > + ctxt->kernel_sp = idle->thread.sp0; > > #ifdef CONFIG_X86_32 > - ctxt->event_callback_cs = __KERNEL_CS; > - ctxt->failsafe_callback_cs = __KERNEL_CS; > + ctxt->event_callback_cs = __KERNEL_CS; > + ctxt->failsafe_callback_cs = __KERNEL_CS; > #endif > - ctxt->event_callback_eip = (unsigned long)xen_hypervisor_callback; > - ctxt->failsafe_callback_eip = (unsigned long)xen_failsafe_callback; > + ctxt->event_callback_eip = > + (unsigned long)xen_hypervisor_callback; > + ctxt->failsafe_callback_eip = > + (unsigned long)xen_failsafe_callback; > + } > + ctxt->user_regs.cs = __KERNEL_CS; > + ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs); > > per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir); > ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir)); The tradional path looks the same as before, however it is hard to tell whether the PVH path is correct without the Xen side. For example, what is gdtsz? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/