From 795f99b61d20c34cb04d17d8906b32f745a635ec Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge <jeremy@goop.org> Date: Fri, 30 Jan 2009 17:47:54 +0900 Subject: [PATCH] xen: setup percpu data pointers Impact: fix xen booting We need to access percpu data fairly early, so set up the percpu registers as soon as possible. We only need to load the appropriate segment register. We already have a GDT, but its hard to change it early because we need to manipulate the pagetable to do so, and that hasn't been set up yet. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Tejun Heo <tj@kernel.org> --- arch/x86/xen/enlighten.c | 3 +++ arch/x86/xen/smp.c | 5 ++++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index bef941f614514..fe19c88a50299 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1647,6 +1647,9 @@ asmlinkage void __init xen_start_kernel(void) have_vcpu_info_placement = 0; #endif + /* setup percpu state */ + load_percpu_segment(0); + xen_smp_init(); /* Get mfn list */ diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 7735e3dd359c5..88d5d5ec6bebb 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -170,7 +170,8 @@ static void __init xen_smp_prepare_boot_cpu(void) /* We've switched to the "real" per-cpu gdt, so make sure the old memory can be recycled */ - make_lowmem_page_readwrite(&per_cpu_var(gdt_page)); + make_lowmem_page_readwrite(__per_cpu_load + + (unsigned long)&per_cpu_var(gdt_page)); xen_setup_vcpu_info_placement(); } @@ -235,6 +236,8 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle) ctxt->user_regs.ss = __KERNEL_DS; #ifdef CONFIG_X86_32 ctxt->user_regs.fs = __KERNEL_PERCPU; +#else + 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 */ -- GitLab